Characteristics of co-composts produced from raw faecal ...
ORIGINAL RESEARCH International Journal of Recycling of Organic Waste in Agriculture (2020)9: 333-347 DOI:10.30486/IJROWA.2020.1898218.1062 Characteristics of co-composts produced from raw faecal sludge and organic market waste in Osun state, southwest Nigeria Olufemi O Aluko 1, 2* , Elizabeth O Oloruntoba 1 , Godson R.E.E Ana 1 , Taiwo B Hammed 1 , Olusegun T Afolabi 2 Received: 08 May 2020 / Accepted: 17 August 2020 / Published online: 20 December 2020 Abstract Purpose Faecal sludge (FS) and organic market waste (MW) have resources that could be recovered by co-com- posting though not fully explored under changing climatic conditions in Nigeria. This study explored the charac- teristics and nutrient quality of co-composts produced from pre-treated FS and MW feedstocks in Nigeria. Method The study was exploratory and analytical in design and co-composting was purposively selected for re- source-recovery. The raw faecal sludge (FS) was harvested from septic tanks of households (50%) and institutions (50%) through mechanical evacuation service trucks and dewatered using 0.1% gradient sand filter. The biode- gradable MW was sorted and used for further studies. The dewatered FS (DFS) and MW were mixed in ratios 1:3, 1:5 and 1:7, respectively with DFS and MW as controls. Each of the mixes was made into 1m 3 heap and co-com- posted using the windrow method. The experiments were monitored for 88 days with fortnight composite sampling from each mix (13-weeks). The samples were analyzed for temperature, pH, moisture-contents, micronutrients, macronutrients and pollutants using Standard Methods. Results At maturity, N:P:K (%) indicate good composts at 9: 5: 4, 18: 7: 19 and 3: 3: 1 in the 1: 3, 1: 5 and 1: 7 mix- es, respectively, while those of controls were: 19:12:12 (DFS) and 17:14:11(MW) with no significant differences between experimental and control mixes. Also, four factors extracted (pollutants, agronomic, macronutrients and micronutrients), explained 78.2% variability. Conclusion The matured co-compost satisfied nutrients and pollutants quality for agricultural use, recovered or- ganic fertiliser from raw domestic and institutional faecal sludge and market waste. Keywords Resource recovery, Co-composting, Dewatered faecal sludge, Organic market waste, Organic fertilizer, Nigeria Department of Environmental Health Sciences, Faculty of Public Health, University of Ibadan, Nigeria Department of Community Health, College of Health Sciences, Obafemi Awolowo University, Nigeria 1 2 Olufemi O. Aluko [email protected] Abbreviations Al APHA CI C: N CLTS DFS FCT FI FS FSC FSM K LGA MC MDGs Mg MICS MSW MW OAU OSS OWMA P PCs PCA PLS PIXE S SANDEC SDGs SSA SWC TCC TKN TOC UCH Zn Aluminium American public health association Clean index Carbon: nitrogen Community led total sanitation Dewatered faecal sludge Federal capital territory Fertilising index Faecal sludge Faecal sludge control Faecal sludge management Potassium Local government area Moisture content Millennium development goals Magnesium Multi-indicator cluster survey Municipal solid waste Organic market waste Obafemi Awolowo university, Ile-Ife On-site sanitation Osun state waste management agency Phosphorus Principal components Principal component analysis Partial least squares Proton Induced x-ray Emissions Sulphur Sanitation in developing countries of the Swiss federal institute of aquatic science and technology Sustainable development goals Sub-saharan africa Solid waste control Total coliform count Total kjeldahl nitrogen Total organic carbon University college hospital, Ibadan, Nigeria Zinc
Transcript of Characteristics of co-composts produced from raw faecal ...
ORIGINAL RESEARCH
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347DOI1030486IJROWA202018982181062
Characteristics of co-composts produced from raw faecal sludge and organic market waste in Osun state southwest Nigeria
Olufemi O Aluko1 2 Elizabeth O Oloruntoba1 Godson REE Ana1 Taiwo B Hammed1 Olusegun T Afolabi2
Received 08 May 2020 Accepted 17 August 2020 Published online 20 December 2020
AbstractPurpose Faecal sludge (FS) and organic market waste (MW) have resources that could be recovered by co-com-posting though not fully explored under changing climatic conditions in Nigeria This study explored the charac-teristics and nutrient quality of co-composts produced from pre-treated FS and MW feedstocks in Nigeria Method The study was exploratory and analytical in design and co-composting was purposively selected for re-source-recovery The raw faecal sludge (FS) was harvested from septic tanks of households (50) and institutions (50) through mechanical evacuation service trucks and dewatered using 01 gradient sand filter The biode-gradable MW was sorted and used for further studies The dewatered FS (DFS) and MW were mixed in ratios 13 15 and 17 respectively with DFS and MW as controls Each of the mixes was made into 1m3 heap and co-com-posted using the windrow method The experiments were monitored for 88 days with fortnight composite sampling from each mix (13-weeks) The samples were analyzed for temperature pH moisture-contents micronutrients macronutrients and pollutants using Standard MethodsResults At maturity NPK () indicate good composts at 9 5 4 18 7 19 and 3 3 1 in the 1 3 1 5 and 1 7 mix-es respectively while those of controls were 191212 (DFS) and 171411(MW) with no significant differences between experimental and control mixes Also four factors extracted (pollutants agronomic macronutrients and micronutrients) explained 782 variabilityConclusion The matured co-compost satisfied nutrients and pollutants quality for agricultural use recovered or-ganic fertiliser from raw domestic and institutional faecal sludge and market waste
Keywords Resource recovery Co-composting Dewatered faecal sludge Organic market waste Organic fertilizer Nigeria
Department of Environmental Health Sciences Faculty of Public Health University of Ibadan NigeriaDepartment of Community Health College of Health Sciences Obafemi Awolowo University Nigeria
1
2
Olufemi O Aluko ooalukogmailcom
AbbreviationsAlAPHACIC NCLTSDFSFCTFIFSFSCFSMK LGAMCMDGs
MgMICSMSWMWOAUOSSOWMAPPCsPCAPLSPIXE S SANDEC
SDGsSSASWCTCCTKNTOCUCHZn
AluminiumAmerican public health associationClean indexCarbon nitrogenCommunity led total sanitationDewatered faecal sludgeFederal capital territoryFertilising indexFaecal sludgeFaecal sludge controlFaecal sludge managementPotassiumLocal government areaMoisture contentMillennium development goals
MagnesiumMulti-indicator cluster surveyMunicipal solid wasteOrganic market wasteObafemi Awolowo university Ile-IfeOn-site sanitationOsun state waste management agencyPhosphorusPrincipal componentsPrincipal component analysisPartial least squaresProton Induced x-ray EmissionsSulphurSanitation in developing countries of the Swiss federal institute of aquatic science and technologySustainable development goalsSub-saharan africaSolid waste controlTotal coliform countTotal kjeldahl nitrogenTotal organic carbonUniversity college hospital Ibadan NigeriaZinc
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347334
Introduction
Waste management channels waste through practically economically and technically appropriate recovery or disposal routes in compliance with public health stan-dards (Suess and Huismans 1983) By convention solid waste management is a municipal responsibility though inadequate services dominate waste management in most local government areas (LGAs) in Nigeria The millennium development goals (MDGs) advanced up-take in sanitation services at the household level with-out considering faecal sludge management which has been corrected through the sustainable development goal (SDG) 62 (McGranahan 2015)
In Nigeria very few geographical entities such as the federal capital territory (FCT) and the pioneer tertiary institutions such as the Obafemi Awolowo university (OAU) and the university college hospital (UCH) Ibadan have the conventional sewerage sys-tem Most households depended on on-site sanitation systems (OSS) (Strauss et al 2000 Strande et al 2014 Jenkins et al 2015 Rao et al 2017) and about 27 billion people rely on OSS globally (Rao et al 2017 Semiyaga et al 2017) which accumulate faecal sludge (FS) The FS fill-up rate is dependent on vaults diameter width and depth the number of users the frequency of use and groundwater level (Strande et al 2014)
The Multi-indicator cluster survey (MICS) revealed that 247 of the population in Osun state have ac-cess to improved sanitation facilities (NBSUNICEF 2017) In Nigeria the community-led total sanitation (CLTS) is the national strategy to achieve open defeca-tion free status a programme that majorly focussed on excreta containment without planning for faecal sludge management (FSM) (Chuah and Ziegler 2018) Raw FS contains organic pollutants and pathogens (WHO 2010) though Otterpohl et al (1997) and Singh et al (2017) showed that dewatered FS (DFS) is rich in organic matter and nutrients that require sanitization before use in agriculture Usually FSM should be pro-ductively managed with resources recovered through centralised and point management structures In Nige-ria however FSM is a challenge and its management lacks the infrastructure and political will thereby rele-gated in developmental priorities and decision-making FS is therefore discharged in dumpsites stagnated and open water resources and on farms at the instance of some farmers Due to the scarcity and costly chemical
fertilizers attention is placed on organic fertilisers a fulcrum for sustainable resource recovery from FS and MW in Nigeria hence this study
Materials and methods
Description of the approved disposal dumpsite in the study area
The study took place at Olusosun dumpsite Osogbo in Osun state in Nigeria between November 2015 and March 2016 The dumpsite was the predominant solid waste disposal facility owned operated and managed by the Osun state waste management agency (OWMA) as at the study period It was in use for municipal solid waste (MSW) disposal by public and private enterpris-es The dumpsite is located at the outskirts of the state capital within the boundaries of Egbedore LGA The dumpsite was characterised by the tropical rainforest and its temperature ranged from 19degC to 34degC and an average of 350 mm rainfall (Oyelami et al 2013) The drainage pattern in the area is dendritic due to a clayey weathered surface layer overlying the complex base-ment rock Some streams and rivers flow northwest and discharge into river Osun (Oyelami et al 2013) Apart from the MSW the dumpsite receives FS emptied by vacuum emptying enterprises There is no FS treatment facility hence FS is discharged in the dumpsite without remediation (Plate 1a)
Pre-treatment of faecal sludge by dewatering and drying
The dewatering and thickening of FS were achieved by the low-cost sedimentationgravity process fol-lowing the guides by Uggetti et al (2009) and Ug-getti et al (2012) The mix of domestic and institu-tional faecal sludge contains water that leached out by gravity thickening before drying The dewatering and drying trough was modelled on Koneacute et al (2004) and had a volume of 462m3 obtained by (549 meters (length) by 366 meters (breadth) and (023 metres (height) (Plate 1b) The system has a slope of 01 outwards for gravitational effluent removal through the filter (fine sandy soil) media The dewatered FS was dried at room temperature to prevent loss of nutri-ents by volatilization The dewatering and dry system ensured 69 volumetric reduction from the raw FS start volume
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 335
Plate 1a Septic sludge discharged in Olusosun dumpsite
Plate 1b The dewatered septic sludge prior to drying
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347336
Fig 1 Feedstock materials processing and aggregates into experimental mixes in the co-composting study
Co-composting of dewatered faecal sludge and sorted market organic wastes
In collaboration with OWMA the study collected or-ganic solid wastes from Igbona Owode and Olaiya markets in Osogbo metropolis The solid waste was aggregated and sorted into organic and lsquootherrsquo wastes following the guides provided by Cofie et al (2009 2016) before the constitution of the various experimen-tal feedstock co-compost piles
Constitution of experimental co-compost piles
Following guides provided by Cofie et al (2009)
Fernaacutendez et al (2010) and Scoton et al (2015) co-composting was performed at ambient climatic con-ditions at temperature (22oC ndash 38oC) humidity (40ndash60 ) and C N (201) mass ratio The study construct1-ed and utilised a 1 m3 (10 m (length) times 10 m (width) times 10 m (height)) graduated mould in constituting the three co-compost and two control piles The co-com-post experimental piles comprised of dewatered FS and sorted organic market wastes in ratios 13 15 and 17 by volume and composted using the aerobic windrow method (Cofie et al 2009 Mengistu et al 2018) (Fig 1) The experimental mixing ratios of FS and MSW were determined by adapting the methods used by Cof-ie et al (2009)
Co-composting method and turning frequency
The aerobic windrow composting method was used with the homogenized feedstock of 1 m3 heaped to conical sizes (Mengistu et al 2018 Nartey et al 2017) The experimental piles were aerated by mix-ing with moisture maintained at between 40 to 60 by manual water sprinkling on the constituted heaps Also the co-compost heaps were turned once in 3 days (Getahun et al 2012) during the initial six weeks and decreased to once in seven days during the
last weeks when the temperature plateaued at room temperature
The co-composting experimental units and sam-pling methods
Following the guide by Costa et al (2016) a composite sample from each of the five experimental piles were obtained immediately after the constitution to establish the quality of the feedstock mixes before the co-com-posting process
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 337
In the co-compost piles temperature pH and mois-ture contents were measured every day from inception until maturity The measurements were taken at three random sampling points with the average presented in the study For elemental analysis sampling was done once at a 2-week interval to establish the performancersquos trends from inception until maturity In this regard two grab samples were collected after thorough mixing of the pile contents (APHA 1998) and constituted into a com-posite sample for each mix and transported immediately to the laboratory for further processing and analysis The samples were oven-dried at 50oC to prevent denaturing and cooled at room temperature before analysis
Methods of analysis for co-composts mixes
In co-compost samples macro-elements (total organic carbon (TOC) total kjeldahl nitrogen (TKN) potas-sium (K) phosphorus (P) and sulphur (S) micro-ele-ments (calcium (Ca) magnesium (Mg) iron (Fe) mo-lybdenum (Mb) sodium (Na) and selenium) pollutant parameters (arsenic (As) lead (Pb) copper (Cu) nickel (Ni) zinc (Zn) cadmium (Cd) chromium (Cr) and the total coliform count (TCC) were analysed using stan-dard methods (APHAAWWAWEF 2005) Tempera-ture moisture content and pH values were measured in-situ with calibrated probes following manufacturersrsquo instructions Measurements were taken in three random points in co-compost heaps at 01m and 03m depths from the highest point and stabilised before recordings Total kjeldahl nitrogen (TKN) in each sample was an-alysed after digestion with sulphuric acid following standard methods (APHAAWWAWEF 2005) Also the proton induced x-ray emission (PIXE) method was used for elemental analysis of co-compost samples at the centre for energy research and development (CERD) of the Obafemi Awolowo university Ile-Ife according to the guide provided by Johansson and Thomas (1976) and Kwiatek et al (1994) Also TCC was estimated by the membrane filtration technique (Bartman and Ped-ley 1996) and computed according to standard methods (APHA 1998) The study data were entered and anal-ysed using IBM-SPSS version 20 software with results presented by the summary and inferential statistics at P α lt 005 The relationships among the co-compost piles were shown through path weights which vary from -1 to +1 with the values closest to 1 reflecting the strongest paths while those closest to 0 reflect the weakest paths (Fan et al 2016 Garson 2016)
Results and discussion
Changes in co-compost temperature pH and moisture content
The temperature of co-compost piles ranged between room temperature 23oC and 63oC during the thermo-philic self-heating phase and subsequently reduced to the mesophilic and room temperature range at maturity (Fig 2a) though their moisture contents were controlled between 429 and 601 to provide the optimum condition for natural biodegradation (Fig 2b) Also pH ranged between 66 and 77 and within the recommend-ed threshold for optimum performance (Fig 2c)
The characteristics of the feedstock co-compost ma-terials (Table 1) showed that temperature was ambient (283oC and 290oC) and moisture contents were opti-mal (490 to 610) The pH ranged from 66 to 69 the TKN averaged 177 (sorted MW) and 282 (de-watered FS) and the C N ratio varied from 223 to 249 Also potassium phosphorus and calcium respectively ranged from 16 to 23 14 to 18 and 12 to 17 Also total coliform count (TCC100ml) ranged from 136 x 107 to 449 x 107
In agreement with Costa et al (2016) the tempera-ture was self-moderating and determines co-composts quality at maturity Except for the FSC pile the tem-perature of experimental co-compost piles reached thermophilic phase within 72 hours in agreement with Karanja et al (2005) and Jeong et al (2017) Tempera-ture progression from mesophilic to thermophilic range in experimental piles indicated the presence of a high degree of biodegradable constituents microbial activ-ity and their self-insulating capacity (Sundberg et al 2004) The temperature range agrees with studies by Scoton et al (2016) and Cheng et al (2017) At tem-peratures above 550C pathogenic microorganisms are decimated in composts in agreement with Cofie et al (2016) and Nartey et al (2017) while Niwagaba et al (2009) showed that high compost temperatures deci-mate pathogens but inadequate to achieve total saniti-sation irrespective of the co-composting method used
The pH range of composts was in congruence with previous studies where a progression in pH was report-ed during co-composting of diverse substrates (Mengis-tu et al 2018 Al-Muyeed et al 2017) The turning fre-quency in co-compost piles was consistent with those in previous studies driven by temperature changes in the sanitisation of matured compost (Koneacute et al 2004
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
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ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
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Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
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- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
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International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347334
Introduction
Waste management channels waste through practically economically and technically appropriate recovery or disposal routes in compliance with public health stan-dards (Suess and Huismans 1983) By convention solid waste management is a municipal responsibility though inadequate services dominate waste management in most local government areas (LGAs) in Nigeria The millennium development goals (MDGs) advanced up-take in sanitation services at the household level with-out considering faecal sludge management which has been corrected through the sustainable development goal (SDG) 62 (McGranahan 2015)
In Nigeria very few geographical entities such as the federal capital territory (FCT) and the pioneer tertiary institutions such as the Obafemi Awolowo university (OAU) and the university college hospital (UCH) Ibadan have the conventional sewerage sys-tem Most households depended on on-site sanitation systems (OSS) (Strauss et al 2000 Strande et al 2014 Jenkins et al 2015 Rao et al 2017) and about 27 billion people rely on OSS globally (Rao et al 2017 Semiyaga et al 2017) which accumulate faecal sludge (FS) The FS fill-up rate is dependent on vaults diameter width and depth the number of users the frequency of use and groundwater level (Strande et al 2014)
The Multi-indicator cluster survey (MICS) revealed that 247 of the population in Osun state have ac-cess to improved sanitation facilities (NBSUNICEF 2017) In Nigeria the community-led total sanitation (CLTS) is the national strategy to achieve open defeca-tion free status a programme that majorly focussed on excreta containment without planning for faecal sludge management (FSM) (Chuah and Ziegler 2018) Raw FS contains organic pollutants and pathogens (WHO 2010) though Otterpohl et al (1997) and Singh et al (2017) showed that dewatered FS (DFS) is rich in organic matter and nutrients that require sanitization before use in agriculture Usually FSM should be pro-ductively managed with resources recovered through centralised and point management structures In Nige-ria however FSM is a challenge and its management lacks the infrastructure and political will thereby rele-gated in developmental priorities and decision-making FS is therefore discharged in dumpsites stagnated and open water resources and on farms at the instance of some farmers Due to the scarcity and costly chemical
fertilizers attention is placed on organic fertilisers a fulcrum for sustainable resource recovery from FS and MW in Nigeria hence this study
Materials and methods
Description of the approved disposal dumpsite in the study area
The study took place at Olusosun dumpsite Osogbo in Osun state in Nigeria between November 2015 and March 2016 The dumpsite was the predominant solid waste disposal facility owned operated and managed by the Osun state waste management agency (OWMA) as at the study period It was in use for municipal solid waste (MSW) disposal by public and private enterpris-es The dumpsite is located at the outskirts of the state capital within the boundaries of Egbedore LGA The dumpsite was characterised by the tropical rainforest and its temperature ranged from 19degC to 34degC and an average of 350 mm rainfall (Oyelami et al 2013) The drainage pattern in the area is dendritic due to a clayey weathered surface layer overlying the complex base-ment rock Some streams and rivers flow northwest and discharge into river Osun (Oyelami et al 2013) Apart from the MSW the dumpsite receives FS emptied by vacuum emptying enterprises There is no FS treatment facility hence FS is discharged in the dumpsite without remediation (Plate 1a)
Pre-treatment of faecal sludge by dewatering and drying
The dewatering and thickening of FS were achieved by the low-cost sedimentationgravity process fol-lowing the guides by Uggetti et al (2009) and Ug-getti et al (2012) The mix of domestic and institu-tional faecal sludge contains water that leached out by gravity thickening before drying The dewatering and drying trough was modelled on Koneacute et al (2004) and had a volume of 462m3 obtained by (549 meters (length) by 366 meters (breadth) and (023 metres (height) (Plate 1b) The system has a slope of 01 outwards for gravitational effluent removal through the filter (fine sandy soil) media The dewatered FS was dried at room temperature to prevent loss of nutri-ents by volatilization The dewatering and dry system ensured 69 volumetric reduction from the raw FS start volume
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 335
Plate 1a Septic sludge discharged in Olusosun dumpsite
Plate 1b The dewatered septic sludge prior to drying
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347336
Fig 1 Feedstock materials processing and aggregates into experimental mixes in the co-composting study
Co-composting of dewatered faecal sludge and sorted market organic wastes
In collaboration with OWMA the study collected or-ganic solid wastes from Igbona Owode and Olaiya markets in Osogbo metropolis The solid waste was aggregated and sorted into organic and lsquootherrsquo wastes following the guides provided by Cofie et al (2009 2016) before the constitution of the various experimen-tal feedstock co-compost piles
Constitution of experimental co-compost piles
Following guides provided by Cofie et al (2009)
Fernaacutendez et al (2010) and Scoton et al (2015) co-composting was performed at ambient climatic con-ditions at temperature (22oC ndash 38oC) humidity (40ndash60 ) and C N (201) mass ratio The study construct1-ed and utilised a 1 m3 (10 m (length) times 10 m (width) times 10 m (height)) graduated mould in constituting the three co-compost and two control piles The co-com-post experimental piles comprised of dewatered FS and sorted organic market wastes in ratios 13 15 and 17 by volume and composted using the aerobic windrow method (Cofie et al 2009 Mengistu et al 2018) (Fig 1) The experimental mixing ratios of FS and MSW were determined by adapting the methods used by Cof-ie et al (2009)
Co-composting method and turning frequency
The aerobic windrow composting method was used with the homogenized feedstock of 1 m3 heaped to conical sizes (Mengistu et al 2018 Nartey et al 2017) The experimental piles were aerated by mix-ing with moisture maintained at between 40 to 60 by manual water sprinkling on the constituted heaps Also the co-compost heaps were turned once in 3 days (Getahun et al 2012) during the initial six weeks and decreased to once in seven days during the
last weeks when the temperature plateaued at room temperature
The co-composting experimental units and sam-pling methods
Following the guide by Costa et al (2016) a composite sample from each of the five experimental piles were obtained immediately after the constitution to establish the quality of the feedstock mixes before the co-com-posting process
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 337
In the co-compost piles temperature pH and mois-ture contents were measured every day from inception until maturity The measurements were taken at three random sampling points with the average presented in the study For elemental analysis sampling was done once at a 2-week interval to establish the performancersquos trends from inception until maturity In this regard two grab samples were collected after thorough mixing of the pile contents (APHA 1998) and constituted into a com-posite sample for each mix and transported immediately to the laboratory for further processing and analysis The samples were oven-dried at 50oC to prevent denaturing and cooled at room temperature before analysis
Methods of analysis for co-composts mixes
In co-compost samples macro-elements (total organic carbon (TOC) total kjeldahl nitrogen (TKN) potas-sium (K) phosphorus (P) and sulphur (S) micro-ele-ments (calcium (Ca) magnesium (Mg) iron (Fe) mo-lybdenum (Mb) sodium (Na) and selenium) pollutant parameters (arsenic (As) lead (Pb) copper (Cu) nickel (Ni) zinc (Zn) cadmium (Cd) chromium (Cr) and the total coliform count (TCC) were analysed using stan-dard methods (APHAAWWAWEF 2005) Tempera-ture moisture content and pH values were measured in-situ with calibrated probes following manufacturersrsquo instructions Measurements were taken in three random points in co-compost heaps at 01m and 03m depths from the highest point and stabilised before recordings Total kjeldahl nitrogen (TKN) in each sample was an-alysed after digestion with sulphuric acid following standard methods (APHAAWWAWEF 2005) Also the proton induced x-ray emission (PIXE) method was used for elemental analysis of co-compost samples at the centre for energy research and development (CERD) of the Obafemi Awolowo university Ile-Ife according to the guide provided by Johansson and Thomas (1976) and Kwiatek et al (1994) Also TCC was estimated by the membrane filtration technique (Bartman and Ped-ley 1996) and computed according to standard methods (APHA 1998) The study data were entered and anal-ysed using IBM-SPSS version 20 software with results presented by the summary and inferential statistics at P α lt 005 The relationships among the co-compost piles were shown through path weights which vary from -1 to +1 with the values closest to 1 reflecting the strongest paths while those closest to 0 reflect the weakest paths (Fan et al 2016 Garson 2016)
Results and discussion
Changes in co-compost temperature pH and moisture content
The temperature of co-compost piles ranged between room temperature 23oC and 63oC during the thermo-philic self-heating phase and subsequently reduced to the mesophilic and room temperature range at maturity (Fig 2a) though their moisture contents were controlled between 429 and 601 to provide the optimum condition for natural biodegradation (Fig 2b) Also pH ranged between 66 and 77 and within the recommend-ed threshold for optimum performance (Fig 2c)
The characteristics of the feedstock co-compost ma-terials (Table 1) showed that temperature was ambient (283oC and 290oC) and moisture contents were opti-mal (490 to 610) The pH ranged from 66 to 69 the TKN averaged 177 (sorted MW) and 282 (de-watered FS) and the C N ratio varied from 223 to 249 Also potassium phosphorus and calcium respectively ranged from 16 to 23 14 to 18 and 12 to 17 Also total coliform count (TCC100ml) ranged from 136 x 107 to 449 x 107
In agreement with Costa et al (2016) the tempera-ture was self-moderating and determines co-composts quality at maturity Except for the FSC pile the tem-perature of experimental co-compost piles reached thermophilic phase within 72 hours in agreement with Karanja et al (2005) and Jeong et al (2017) Tempera-ture progression from mesophilic to thermophilic range in experimental piles indicated the presence of a high degree of biodegradable constituents microbial activ-ity and their self-insulating capacity (Sundberg et al 2004) The temperature range agrees with studies by Scoton et al (2016) and Cheng et al (2017) At tem-peratures above 550C pathogenic microorganisms are decimated in composts in agreement with Cofie et al (2016) and Nartey et al (2017) while Niwagaba et al (2009) showed that high compost temperatures deci-mate pathogens but inadequate to achieve total saniti-sation irrespective of the co-composting method used
The pH range of composts was in congruence with previous studies where a progression in pH was report-ed during co-composting of diverse substrates (Mengis-tu et al 2018 Al-Muyeed et al 2017) The turning fre-quency in co-compost piles was consistent with those in previous studies driven by temperature changes in the sanitisation of matured compost (Koneacute et al 2004
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
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Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 335
Plate 1a Septic sludge discharged in Olusosun dumpsite
Plate 1b The dewatered septic sludge prior to drying
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347336
Fig 1 Feedstock materials processing and aggregates into experimental mixes in the co-composting study
Co-composting of dewatered faecal sludge and sorted market organic wastes
In collaboration with OWMA the study collected or-ganic solid wastes from Igbona Owode and Olaiya markets in Osogbo metropolis The solid waste was aggregated and sorted into organic and lsquootherrsquo wastes following the guides provided by Cofie et al (2009 2016) before the constitution of the various experimen-tal feedstock co-compost piles
Constitution of experimental co-compost piles
Following guides provided by Cofie et al (2009)
Fernaacutendez et al (2010) and Scoton et al (2015) co-composting was performed at ambient climatic con-ditions at temperature (22oC ndash 38oC) humidity (40ndash60 ) and C N (201) mass ratio The study construct1-ed and utilised a 1 m3 (10 m (length) times 10 m (width) times 10 m (height)) graduated mould in constituting the three co-compost and two control piles The co-com-post experimental piles comprised of dewatered FS and sorted organic market wastes in ratios 13 15 and 17 by volume and composted using the aerobic windrow method (Cofie et al 2009 Mengistu et al 2018) (Fig 1) The experimental mixing ratios of FS and MSW were determined by adapting the methods used by Cof-ie et al (2009)
Co-composting method and turning frequency
The aerobic windrow composting method was used with the homogenized feedstock of 1 m3 heaped to conical sizes (Mengistu et al 2018 Nartey et al 2017) The experimental piles were aerated by mix-ing with moisture maintained at between 40 to 60 by manual water sprinkling on the constituted heaps Also the co-compost heaps were turned once in 3 days (Getahun et al 2012) during the initial six weeks and decreased to once in seven days during the
last weeks when the temperature plateaued at room temperature
The co-composting experimental units and sam-pling methods
Following the guide by Costa et al (2016) a composite sample from each of the five experimental piles were obtained immediately after the constitution to establish the quality of the feedstock mixes before the co-com-posting process
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 337
In the co-compost piles temperature pH and mois-ture contents were measured every day from inception until maturity The measurements were taken at three random sampling points with the average presented in the study For elemental analysis sampling was done once at a 2-week interval to establish the performancersquos trends from inception until maturity In this regard two grab samples were collected after thorough mixing of the pile contents (APHA 1998) and constituted into a com-posite sample for each mix and transported immediately to the laboratory for further processing and analysis The samples were oven-dried at 50oC to prevent denaturing and cooled at room temperature before analysis
Methods of analysis for co-composts mixes
In co-compost samples macro-elements (total organic carbon (TOC) total kjeldahl nitrogen (TKN) potas-sium (K) phosphorus (P) and sulphur (S) micro-ele-ments (calcium (Ca) magnesium (Mg) iron (Fe) mo-lybdenum (Mb) sodium (Na) and selenium) pollutant parameters (arsenic (As) lead (Pb) copper (Cu) nickel (Ni) zinc (Zn) cadmium (Cd) chromium (Cr) and the total coliform count (TCC) were analysed using stan-dard methods (APHAAWWAWEF 2005) Tempera-ture moisture content and pH values were measured in-situ with calibrated probes following manufacturersrsquo instructions Measurements were taken in three random points in co-compost heaps at 01m and 03m depths from the highest point and stabilised before recordings Total kjeldahl nitrogen (TKN) in each sample was an-alysed after digestion with sulphuric acid following standard methods (APHAAWWAWEF 2005) Also the proton induced x-ray emission (PIXE) method was used for elemental analysis of co-compost samples at the centre for energy research and development (CERD) of the Obafemi Awolowo university Ile-Ife according to the guide provided by Johansson and Thomas (1976) and Kwiatek et al (1994) Also TCC was estimated by the membrane filtration technique (Bartman and Ped-ley 1996) and computed according to standard methods (APHA 1998) The study data were entered and anal-ysed using IBM-SPSS version 20 software with results presented by the summary and inferential statistics at P α lt 005 The relationships among the co-compost piles were shown through path weights which vary from -1 to +1 with the values closest to 1 reflecting the strongest paths while those closest to 0 reflect the weakest paths (Fan et al 2016 Garson 2016)
Results and discussion
Changes in co-compost temperature pH and moisture content
The temperature of co-compost piles ranged between room temperature 23oC and 63oC during the thermo-philic self-heating phase and subsequently reduced to the mesophilic and room temperature range at maturity (Fig 2a) though their moisture contents were controlled between 429 and 601 to provide the optimum condition for natural biodegradation (Fig 2b) Also pH ranged between 66 and 77 and within the recommend-ed threshold for optimum performance (Fig 2c)
The characteristics of the feedstock co-compost ma-terials (Table 1) showed that temperature was ambient (283oC and 290oC) and moisture contents were opti-mal (490 to 610) The pH ranged from 66 to 69 the TKN averaged 177 (sorted MW) and 282 (de-watered FS) and the C N ratio varied from 223 to 249 Also potassium phosphorus and calcium respectively ranged from 16 to 23 14 to 18 and 12 to 17 Also total coliform count (TCC100ml) ranged from 136 x 107 to 449 x 107
In agreement with Costa et al (2016) the tempera-ture was self-moderating and determines co-composts quality at maturity Except for the FSC pile the tem-perature of experimental co-compost piles reached thermophilic phase within 72 hours in agreement with Karanja et al (2005) and Jeong et al (2017) Tempera-ture progression from mesophilic to thermophilic range in experimental piles indicated the presence of a high degree of biodegradable constituents microbial activ-ity and their self-insulating capacity (Sundberg et al 2004) The temperature range agrees with studies by Scoton et al (2016) and Cheng et al (2017) At tem-peratures above 550C pathogenic microorganisms are decimated in composts in agreement with Cofie et al (2016) and Nartey et al (2017) while Niwagaba et al (2009) showed that high compost temperatures deci-mate pathogens but inadequate to achieve total saniti-sation irrespective of the co-composting method used
The pH range of composts was in congruence with previous studies where a progression in pH was report-ed during co-composting of diverse substrates (Mengis-tu et al 2018 Al-Muyeed et al 2017) The turning fre-quency in co-compost piles was consistent with those in previous studies driven by temperature changes in the sanitisation of matured compost (Koneacute et al 2004
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
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- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
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International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347336
Fig 1 Feedstock materials processing and aggregates into experimental mixes in the co-composting study
Co-composting of dewatered faecal sludge and sorted market organic wastes
In collaboration with OWMA the study collected or-ganic solid wastes from Igbona Owode and Olaiya markets in Osogbo metropolis The solid waste was aggregated and sorted into organic and lsquootherrsquo wastes following the guides provided by Cofie et al (2009 2016) before the constitution of the various experimen-tal feedstock co-compost piles
Constitution of experimental co-compost piles
Following guides provided by Cofie et al (2009)
Fernaacutendez et al (2010) and Scoton et al (2015) co-composting was performed at ambient climatic con-ditions at temperature (22oC ndash 38oC) humidity (40ndash60 ) and C N (201) mass ratio The study construct1-ed and utilised a 1 m3 (10 m (length) times 10 m (width) times 10 m (height)) graduated mould in constituting the three co-compost and two control piles The co-com-post experimental piles comprised of dewatered FS and sorted organic market wastes in ratios 13 15 and 17 by volume and composted using the aerobic windrow method (Cofie et al 2009 Mengistu et al 2018) (Fig 1) The experimental mixing ratios of FS and MSW were determined by adapting the methods used by Cof-ie et al (2009)
Co-composting method and turning frequency
The aerobic windrow composting method was used with the homogenized feedstock of 1 m3 heaped to conical sizes (Mengistu et al 2018 Nartey et al 2017) The experimental piles were aerated by mix-ing with moisture maintained at between 40 to 60 by manual water sprinkling on the constituted heaps Also the co-compost heaps were turned once in 3 days (Getahun et al 2012) during the initial six weeks and decreased to once in seven days during the
last weeks when the temperature plateaued at room temperature
The co-composting experimental units and sam-pling methods
Following the guide by Costa et al (2016) a composite sample from each of the five experimental piles were obtained immediately after the constitution to establish the quality of the feedstock mixes before the co-com-posting process
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 337
In the co-compost piles temperature pH and mois-ture contents were measured every day from inception until maturity The measurements were taken at three random sampling points with the average presented in the study For elemental analysis sampling was done once at a 2-week interval to establish the performancersquos trends from inception until maturity In this regard two grab samples were collected after thorough mixing of the pile contents (APHA 1998) and constituted into a com-posite sample for each mix and transported immediately to the laboratory for further processing and analysis The samples were oven-dried at 50oC to prevent denaturing and cooled at room temperature before analysis
Methods of analysis for co-composts mixes
In co-compost samples macro-elements (total organic carbon (TOC) total kjeldahl nitrogen (TKN) potas-sium (K) phosphorus (P) and sulphur (S) micro-ele-ments (calcium (Ca) magnesium (Mg) iron (Fe) mo-lybdenum (Mb) sodium (Na) and selenium) pollutant parameters (arsenic (As) lead (Pb) copper (Cu) nickel (Ni) zinc (Zn) cadmium (Cd) chromium (Cr) and the total coliform count (TCC) were analysed using stan-dard methods (APHAAWWAWEF 2005) Tempera-ture moisture content and pH values were measured in-situ with calibrated probes following manufacturersrsquo instructions Measurements were taken in three random points in co-compost heaps at 01m and 03m depths from the highest point and stabilised before recordings Total kjeldahl nitrogen (TKN) in each sample was an-alysed after digestion with sulphuric acid following standard methods (APHAAWWAWEF 2005) Also the proton induced x-ray emission (PIXE) method was used for elemental analysis of co-compost samples at the centre for energy research and development (CERD) of the Obafemi Awolowo university Ile-Ife according to the guide provided by Johansson and Thomas (1976) and Kwiatek et al (1994) Also TCC was estimated by the membrane filtration technique (Bartman and Ped-ley 1996) and computed according to standard methods (APHA 1998) The study data were entered and anal-ysed using IBM-SPSS version 20 software with results presented by the summary and inferential statistics at P α lt 005 The relationships among the co-compost piles were shown through path weights which vary from -1 to +1 with the values closest to 1 reflecting the strongest paths while those closest to 0 reflect the weakest paths (Fan et al 2016 Garson 2016)
Results and discussion
Changes in co-compost temperature pH and moisture content
The temperature of co-compost piles ranged between room temperature 23oC and 63oC during the thermo-philic self-heating phase and subsequently reduced to the mesophilic and room temperature range at maturity (Fig 2a) though their moisture contents were controlled between 429 and 601 to provide the optimum condition for natural biodegradation (Fig 2b) Also pH ranged between 66 and 77 and within the recommend-ed threshold for optimum performance (Fig 2c)
The characteristics of the feedstock co-compost ma-terials (Table 1) showed that temperature was ambient (283oC and 290oC) and moisture contents were opti-mal (490 to 610) The pH ranged from 66 to 69 the TKN averaged 177 (sorted MW) and 282 (de-watered FS) and the C N ratio varied from 223 to 249 Also potassium phosphorus and calcium respectively ranged from 16 to 23 14 to 18 and 12 to 17 Also total coliform count (TCC100ml) ranged from 136 x 107 to 449 x 107
In agreement with Costa et al (2016) the tempera-ture was self-moderating and determines co-composts quality at maturity Except for the FSC pile the tem-perature of experimental co-compost piles reached thermophilic phase within 72 hours in agreement with Karanja et al (2005) and Jeong et al (2017) Tempera-ture progression from mesophilic to thermophilic range in experimental piles indicated the presence of a high degree of biodegradable constituents microbial activ-ity and their self-insulating capacity (Sundberg et al 2004) The temperature range agrees with studies by Scoton et al (2016) and Cheng et al (2017) At tem-peratures above 550C pathogenic microorganisms are decimated in composts in agreement with Cofie et al (2016) and Nartey et al (2017) while Niwagaba et al (2009) showed that high compost temperatures deci-mate pathogens but inadequate to achieve total saniti-sation irrespective of the co-composting method used
The pH range of composts was in congruence with previous studies where a progression in pH was report-ed during co-composting of diverse substrates (Mengis-tu et al 2018 Al-Muyeed et al 2017) The turning fre-quency in co-compost piles was consistent with those in previous studies driven by temperature changes in the sanitisation of matured compost (Koneacute et al 2004
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
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Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 337
In the co-compost piles temperature pH and mois-ture contents were measured every day from inception until maturity The measurements were taken at three random sampling points with the average presented in the study For elemental analysis sampling was done once at a 2-week interval to establish the performancersquos trends from inception until maturity In this regard two grab samples were collected after thorough mixing of the pile contents (APHA 1998) and constituted into a com-posite sample for each mix and transported immediately to the laboratory for further processing and analysis The samples were oven-dried at 50oC to prevent denaturing and cooled at room temperature before analysis
Methods of analysis for co-composts mixes
In co-compost samples macro-elements (total organic carbon (TOC) total kjeldahl nitrogen (TKN) potas-sium (K) phosphorus (P) and sulphur (S) micro-ele-ments (calcium (Ca) magnesium (Mg) iron (Fe) mo-lybdenum (Mb) sodium (Na) and selenium) pollutant parameters (arsenic (As) lead (Pb) copper (Cu) nickel (Ni) zinc (Zn) cadmium (Cd) chromium (Cr) and the total coliform count (TCC) were analysed using stan-dard methods (APHAAWWAWEF 2005) Tempera-ture moisture content and pH values were measured in-situ with calibrated probes following manufacturersrsquo instructions Measurements were taken in three random points in co-compost heaps at 01m and 03m depths from the highest point and stabilised before recordings Total kjeldahl nitrogen (TKN) in each sample was an-alysed after digestion with sulphuric acid following standard methods (APHAAWWAWEF 2005) Also the proton induced x-ray emission (PIXE) method was used for elemental analysis of co-compost samples at the centre for energy research and development (CERD) of the Obafemi Awolowo university Ile-Ife according to the guide provided by Johansson and Thomas (1976) and Kwiatek et al (1994) Also TCC was estimated by the membrane filtration technique (Bartman and Ped-ley 1996) and computed according to standard methods (APHA 1998) The study data were entered and anal-ysed using IBM-SPSS version 20 software with results presented by the summary and inferential statistics at P α lt 005 The relationships among the co-compost piles were shown through path weights which vary from -1 to +1 with the values closest to 1 reflecting the strongest paths while those closest to 0 reflect the weakest paths (Fan et al 2016 Garson 2016)
Results and discussion
Changes in co-compost temperature pH and moisture content
The temperature of co-compost piles ranged between room temperature 23oC and 63oC during the thermo-philic self-heating phase and subsequently reduced to the mesophilic and room temperature range at maturity (Fig 2a) though their moisture contents were controlled between 429 and 601 to provide the optimum condition for natural biodegradation (Fig 2b) Also pH ranged between 66 and 77 and within the recommend-ed threshold for optimum performance (Fig 2c)
The characteristics of the feedstock co-compost ma-terials (Table 1) showed that temperature was ambient (283oC and 290oC) and moisture contents were opti-mal (490 to 610) The pH ranged from 66 to 69 the TKN averaged 177 (sorted MW) and 282 (de-watered FS) and the C N ratio varied from 223 to 249 Also potassium phosphorus and calcium respectively ranged from 16 to 23 14 to 18 and 12 to 17 Also total coliform count (TCC100ml) ranged from 136 x 107 to 449 x 107
In agreement with Costa et al (2016) the tempera-ture was self-moderating and determines co-composts quality at maturity Except for the FSC pile the tem-perature of experimental co-compost piles reached thermophilic phase within 72 hours in agreement with Karanja et al (2005) and Jeong et al (2017) Tempera-ture progression from mesophilic to thermophilic range in experimental piles indicated the presence of a high degree of biodegradable constituents microbial activ-ity and their self-insulating capacity (Sundberg et al 2004) The temperature range agrees with studies by Scoton et al (2016) and Cheng et al (2017) At tem-peratures above 550C pathogenic microorganisms are decimated in composts in agreement with Cofie et al (2016) and Nartey et al (2017) while Niwagaba et al (2009) showed that high compost temperatures deci-mate pathogens but inadequate to achieve total saniti-sation irrespective of the co-composting method used
The pH range of composts was in congruence with previous studies where a progression in pH was report-ed during co-composting of diverse substrates (Mengis-tu et al 2018 Al-Muyeed et al 2017) The turning fre-quency in co-compost piles was consistent with those in previous studies driven by temperature changes in the sanitisation of matured compost (Koneacute et al 2004
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
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Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
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ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347338
Fig 2a Temperature changes during the co-composting pe-riod
Fig 2b Moisture content changes during the co-com-posting period
Fig 2c pH changes during the co-com-posting period
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
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320
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078
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038
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010
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500 00
SWC
272
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730
330
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168
169
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101
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111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
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000 nd 003
470
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917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
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140
310
7
Rat
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1 5
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487
5
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175
8
130
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450
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925
107
Rat
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3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
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003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
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Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
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Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
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laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 339
Parameters Unit Dewatered faecal sludge Sorted market solid waste
Temperature oC 283 290
Moisture content Percent 61 49
pH 66 69
Total kjeldahl nitrogen Percent 282 177
Total organic carbon Percent 630 440
Organic matter Percent 156 153
C N ratio 223 249
Potassium (K) Percent 1564 2262
Phosphorus (P) Percent 1812 1395
Sulphur (S) Percent 1471 1273
Calcium (Ca) Percent 1655 1244
Magnesium (Mg) Percent 0634 0427
Iron (Fe) Percent 0135 0105
Sodium (Na) Percent 0151 0136
Copper (Cu) Percent 0007 0002
Zinc (Zn) Percent 0493 0065
Aluminium (Al) Percent 0472 0201
Silicon (Si) Percent 2596 4744
Chloride (Cl) Percent 0236 1056
Manganese (Mn) Percent 0204 0011
Total coliform count TCC100ml 136 x 107 449 x 107
Table 1 Physical chemical and microbiological characteristics of co-compost feedstocks
Parkinson et al 2004 Cofie et al 2009 Nartey et al 2017) Though temperature and pH were self-regulata-ing during the composting process the moisture con-tents were regulated at between 40 and 65 from inception to maturity to prevent moisture from being a process limiting variable
Characteristics of co-composts at various com-posting stages
The initial co-compost heaps were weakly acidic while those of matured composts transited from neutral to weakly basic The moisture contents of the co-com-post at the initial thermophilic and mesophilic phases ranged from 48-64 except when matured and below 40 Also the proportion of TKN varied marginally from the initial co-compost heaps to matured co-com-posts in contrast to a reduction in their organic carbon contents from initial heaps (63) to matured co-com-
post samples (143) The C N ratio reduced from start-up values (249-189) to (101-95) in ma-tured co-composts (Table 2)
The total coliform reduction in matured co-com-post mixes revealed higher reductions in FSC SWC and a marginal reduction in ratio 17 mix in contrast to a 46 increase in the coliform count of 15 mix In co-composts elevated temperatures eliminate patho-gens which may recolonise at mesophilic and room temperature at maturity (Gold et al 2016) due to avail-able nutrients hence the situation in the current study
The recycling of MW is largely dependent on de-mand for sanitised composts (Vergara and Tchobano-glous 2012) whose quality is dependent on the feed-stock properties such as C N ratio pH and organic matter (Kaboreacute et al 2010 Anwar et al 2015) mi-crobiota (Galitskaya et al 2017) and process control conditions (Kaboreacute et al 2010 Anwar et al 2015) The C N ratio macro-nutrients and micro-nutrients of feed-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
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Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
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Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
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Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
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Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
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International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347340
Mat
ured
Sta
ge (r
oom
tem
pera
ture
)
Rat
io
1 7
272
0
730
350
0
147
143
0
970
048
146
123
151
055
077
012
001
006
001
002
410
500
85
Rat
io
1 5
273
0
710
320
0
182
173
0
950
189
070
035
142
058
087
014
001
007
001
002
470
500
460
+
Rat
io
1 3
271
0
720
340
0
175
169
0
970
078
100
062
128
038
063
010
001
001
001
003
460
500 00
SWC
272
0
730
330
0
168
169
0
101
0
111
138
076
157
079
156
022
000
002
001
002
450
500
978
FSC
268
0
720
350
0
187
180
1
960
115
124
063
155
042
055
009
001
000 nd 003
470
500
917
Mes
ophi
lic st
age
(le 4
4 degC
)
Rat
io 1
7
332
3
728
482
5
149
158
0
113
5
123
108
063
143
049
083
011
001
015
001
002
450
410
140
310
7
Rat
io
1 5
341
3
730
487
5
145
175
8
130
3
110
112
076
138
046
083
014
001
017
002
002
450
410
925
107
Rat
io
1 3
341
3
735
485
0
160
177
5
116
3
181
121
077
165
058
088
021
000
009
001
003
450
450
463
107
SWC
328
0
725
492
5
182
203
0
112
0
183
073
048
128
056
104
017
000
002
001
002
480
450
831
07
FSC
334
5
708
510
0
152
222
3
152
0
049
151
132
151
054
080
016
001
011 nd 003
440
450
571
07
The
rmop
hilic
stag
e (ge
45 degC
)
Rat
io
1 7
495
0
750
500
0
140
270
0
193
0
175
071
050
152
056
084
018
001
001
001
002
460
460
571
07
Rat
io
1 5
476
0
750
525
0
180
254
0
141
0
203
107
143
145
065
070
016
001
015
001
002
480
430
135
107
Rat
io
1 3
516
0
760
480
0
130
215
0
165
0
146
119
098
161
057
072
023
001
007
001
002
460
430
985
107
SWC
483
0
750
525
0
150
370
0
247
0
152
119
093
161
071
097
023
000
003
001
003
480
470
815
107
FSC
386
0
700
510
0
200
394
0
197
0
109
120
089
136
056
081
015
001
002 Nd
003
460
440
781
07
(Fee
dsto
ck st
age
(roo
m te
mpe
ratu
re
Rat
io
1 7
297
0
710
640
0
245
490
0
200
0
165
175
149
179
071
013
020 nd 039
001
002
440
430
361
07
Rat
io
1 5
294
0
700
640
0
198
450
0
227
3
262
131
084
154
067
011
015
001
028
001
001
440
430
151
07
Rat
io
1 3
286
0
680
660
0
185
330
0
188
6
138
153
113
159
060
015
016
000
034
002
002
460
410
121
07
SWC
290
0
690
490
0
177
440
0
248
6
226
140
127
124
043
011
014
000
006
003
001
440
400
499
107
FSC
283
0
660
610
0
282
630
0
223
4
156
181
147
166
063
014
015
001
049 Nd
020
440
450
132
107
Para
met
ers
(Uni
t)
Tem
p (o C
)
pH
MC
()
TKN
()
TOC
()
C N
()
K (
)
P (
)
S (
)
Ca
()
Mg
()
Fe (
)
Na
()
Cu
()
Zn (
)
Cr (
)
Mn
()
FI CI
TCC
valu
e
Tab
le 2
Cha
ract
eris
tics o
f co-
com
post
hea
ps a
t var
ious
trea
tmen
t sta
ges d
urin
g th
e co
-com
post
ing
proc
ess
B T
emp=
tem
pera
ture
MC
= m
oist
ure
cont
ent
FI=
ferti
lisin
g in
dex
CI=
cle
an in
dex
TC
C=t
otal
col
iform
cou
nt (T
CC
100
ml)
=
redu
ctio
n (
) +=
incr
ease
()
Nd=
not
det
ecta
ble
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
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Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
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International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 341
Table 3 Macronutrients loss in the thermophilic and matured stages in co-composts
Compost Heaps
Total organic carbon (TOC)
Total Kjeldahl Nitrogen (TKN)
Phosphorus (P) Potassium (K) Sulphur (S)
T () M () T () M () T () M () T () M () T () M ()
FSC 375 714 291 337 339 319 304 267 395 574
SWC 159 616 153 51 144 10 330 507 273 405
Ratio 13 348 488 297 54 221 346 -55 438 139 451
Ratio 15 436 616 91 81 182 462 224 279 -700 588
Ratio 17 449 708 429 400 594 165 -60 706 667 174
Key FSC= faecal sludge control SWC= solid waste control T=co-compost heaps at thermophilic stage M= Co-compost heaps at matured stage
stock materials were optimal and consistent with those Fernaacutendez et al (2010) Lohri et al (2017) and Nartey et al (2017) though had a high coliform counts that exceeded the threshold limit of lt1000 CFUg for com-post (IRC 2015) Hence the feedstock materials if used without sanitising can result in soil and farm produce contamination (Nartey et al 2017)
Macronutrients and micronutrients quality at thermophilic and matured co-compost stages
The co-compost mixes recorded a loss in macronutri-
ents such as organic carbon nitrogen P K and S at thermophilic and matured stages corresponding to progressive mineralisation of organic carbon of 159 and 714 respectively for SWC and FSC at maturi-ty The co-compost ratio 15 had the lowest nitrogen loss (91) at the thermophilic stage while at maturi-ty the co-compost ratio 17 had the highest nitrogen loss (400) However there were increases in K of co-compost ratios 13 and 17 at the thermophilic stage of bioconversion while ratio 17 had the highest K loss (706) at maturity (Table 3)
The progressive decreases in TOC contents were in agreement with those reported by previous studies (Mengistu et al 2018 Cofie et al 2009 Anwar et al 2015 Al-Muyeed et al 2017 Krishnan et al 2017 Singh et al 2017) The rate of carbon mineralisation was highest during the thermophilic stage in conso-nance with Anwar et al (2015) though TOC loss (159-449) was lower when compared with those of Tiquia et al (2002) where the TOC ranged from 50 to 63 in aerobic windrows
The progressive loss in nitrogen during the thermo-philic co-composting was similar to those reported by Mengistu et al (2018) perhaps due to the formation and volatilization of ammonia during the active composting phases In contrast the co-compost piles at mesophilic and matured stages had a higher proportion of nitro-gen though lower than those of the initial piles The progressive increase in nitrogen may be due to the con-centration effect that resulted from biodegradation of organic carbon compounds resulting in the weight-vol-ume loss which might show relatively as an increase in
the approximate nitrogen base (Dias et al 2010) Rather than agreeing with Mengistu et al (2018) that nitrogen losses occurred at a higher rate than organic matter min-eralisation during the thermophilic stage a possibility by Wang et al (2016) is fixing atmospheric nitrogen by Nitrosomonas in the co-composts under aerobic condi-tions during the later stages of composting However suggested that Nitrosomonas are inhibited at tempera-tures gt 40oC and only activated during the later meso-philic Morisaki et al (1989) and maturation stages
In composting the C N ratio portends compost ma-turity and its reduction is caused largely by microbial mineralisation of organic carbon A gradual reduction in the C N ratio in all experimental heaps was consis-tent with the works of Gao et al (2010) and Costa et al (2016) The matured compost had C N ratio below 15 this is in line with studies by Bernal et al (2009) Al-Muyeed et al (2017) and Mengistu et al (2018) though in contrast to the C N ratio of 258 by Adewumi et al (2005) with poultry manure and municipal solid waste as feedstocks
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347342
Table 4 Initial eigenvalues and total variance explained by the PCA model
Components Eigenvalue (total) Percent () of variance Cumulative
1 3974 26494 26494
2 3300 22002 48496
3 2845 18968 67464
4 1604 10696 78159
5 0842 5615 83774
6 0663 4418 88192
7 0436 2905 91097
8 0354 2362 93459
9 0323 2154 95613
10 0205 1368 96981
11 0151 1006 97988
12 0115 0769 98757
13 0079 0524 99281
14 0061 0406 99687
15 0047 0313 100000
PCA = Principal component analysis
The N P K values of 1820 0703 and 1886 were equivalent to about 182kgm3 of nitrogen 703 kgm3 of Phosphorus as phosphate and 1886 kgm3 of potassium as the primary macronutrients of the ratio 15 dewatered FS MSW co-compost mix The com-post properties improved soil properties by increasing its aeration and water holding capacity according to Mandal et al (2014) and Anwar et al (2015) Similarly the phosphorus value in the matured co-composts was lower than the threshold for organic compost in Nige-ria In contrast potassium value exceeded the national special programme on food security guideline range of 15-30 and 10-15 respectively
Also the highest potassium value in FS (078) before thermal treatment by Osibote et al (2016) was lower than those used in this study but at par when com-pared with those contained in the matured co-composts This suggests that the FS has lower initial potassium and phosphorus values when compared to those of oth-er countries such as Ghana perhaps due to diet and soil conditions among others Moreover the micronutrient in the matured composts was permissible and should
support plant growth in trace quantities (Anwar et al 2015) The macronutrients and micronutrients quality of the study co-composts were within the guidelinesrsquo values provided by IWMI and SANDEC (2002) How-ever one of the challenges in compost regulation is the divergent threshold values for parameters and varied from country to country where developed This should however be standardized globally to allow compari-son within and between countries The compost quali-ty was in harmony with the quality control indices ob-tained by Vinod and Ravindernath (2015) in India was within the permissible limits prescribed by the fertiliser control order (India)
Multivariate exploratory analysis of co-compost variables
In the multivariate relationships among co-composts parameters the eigenvalues extracted four factors and fifteen components that explained 782 of its variabil-ity (Table 4)
675 of the variance could be explained respec-tively by principal component (PC1) (265) PC2 (220) PC3 (190) and PC4 (107) Chromium is one of the composite index parameters for clean in-
dex (Vinod and Ravindernath 2015) and previous stud-ies identified it in garden and kitchen waste however with progressive mineralisation from the feedstock to matured co-compost piles (Hanc et al 2012) The
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 343
Table 5 Principal component loadings of the co-compost data
Component score coefficient matrix
ParametersPrincipal components (PCs)
PC 1 PC 2 PC 3 PC 4Total Kjedhal nitrogen 0267 0198 -0189 -0029
Clean Index 0245 -0012 -0058 -0088Chromium (Cr) -0234 -0040 -0058 0026Fertilising index 0214 0007 -0120 0131
Silicon (Si) -0169 0126 -0111 -0094Aluminium (Al) -0035 0288 -0041 -0073
Zinc (Zn) -0041 0281 -0019 -0087Total organic carbon 0100 0235 -0052 0038
Mg K ratio -0041 -0083 0350 0094Potassium (K) 0063 0060 -0262 0133Phosphorus (P) -0044 0155 0255 0068
Sulphur (S) 0022 0141 0227 0108Sodium (Na) -0107 -0121 0112 0432
Magnesium (Mg) 0036 0023 0076 0373Cupper (Cu) 0175 -0006 0066 -0195
Extraction method Principal component analysis Rotation method Varimax with Kaiser normalization Component Scores
abundance of chromium in kitchen and garden waste has been demonstrated by previous studies (Deacuteportes et al 1995 Stefanakis et al 2011 Hanc et al 2012) The variables that defined PC 1 were TKN chromium silicon fertilising index and clean index This factor groups the properties associated with compost maturi-ty based on their fertilising and pollutant indices apart from nitrogen which is a process limiting variable All the parameters were positively correlated except chro-mium and silicon In PC 2 Al Zn and TOC defined the agronomic character of co-composts showed a positive correlation and the variables progressively decreased as the compost matures PC 3 was defined by the macro-nutrientsrsquo variables Mg K ratio K P and S In Factor 3 only P was negatively correlated PC 4 was essen-tially micronutrients with only Cu negatively correlated (Table 5)
Further the paths of co-compost variables from quality micronutrients and pollutants present a nega-tive coefficient (0015 and 0012) Macronutrients and process control indices had a coefficient of positive val-ues (0951 and 0062) indicating negative and positive effects on co-compost quality respectively The endog-enous variables explained 977 of the co-compostsrsquo variance contributed by macronutrients micronutri-ents process control and pollutant indices The model has an increasing indirect path in micronutrients pol-lutants process control and macronutrients The partial least scores (PLS) of paths analysis showed that macro-nutrients as a block has the highest correlation (0951) while others showed weak correlation values (Fig 3)
The multivariate data analysis classified parameters into factors according to the guide provided by Soares et al (2017) The variables that defined the predomi-
nant factor were TKN Chromium Silicon Fertilising index and clean index apart from Nitrogen which is a macronutrient required for plant growth (Brinton 2000 Mandal et al 2014) PC 2 defined the agronomic char-acteristics of the matured co-compost and the parame-ters progressively decreased by mineralisation during the composting process PC 3 denotes essential macro-
nutrients Mg K ratio K P and S with the only P being negatively correlated while PC 4 loaded micronutrients with the only Cu negatively correlated The macronu-trients and process control indices had a positive effect on co-compost quality while the micronutrients and pollutants indices exhibited a negative effect on the co-compost quality
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347344
Fig 3 Path analysis of variables in the five co-compost piles
Conclusion
The study revealed mixed but similar results in the co-composting study using ratios 13 15 and 17 mix-es The co-compost feedstock materials and matured compost blends had high coliform counts beyond the threshold limit of lt1000 CFUg for matured compost The matured co-compost blends satisfied the macro-nutrientsrsquo micronutrientsrsquo and acceptable pollutantsrsquo quality suitable for all agricultural demands in soil conditioning and fertilising procedures Therefore the study showed that the co-composting of dewatered fae-cal sludge with the organic market waste is a potential resource recovery strategy which should be optimised to arrest the perennial discharge of raw faecal sludge into the environment
Funding
This research did not receive any specific grant from funding agencies in the public commercial or not-for-profit sectors
Acknowledgements The authors acknowledge the moral sup-
port of the ministry of environment and the waste management
agency in Osun state Nigeria in particular sanitarian Wale
Ogungbe (director environmental sanitation ministry of envi-
ronment) Alh Ganiyu Oyeladun (general manager OWMA) Mr
Henry Olufemi Ogunbamiwo (director environmental health and
sanitation OWMA) and sanitarian Surulere Fatai Oyewole who
guided and advised on administrative and technical convenience
in the cause of the research The authors appreciate the manage-
ment of the centre for energy research and development of the
Obafemi Awolowo university for undertaking the elemental anal-
ysis using proton induced x-ray emissions technology at a dis-
counted price for all study samples We are also appreciative of
the staff of the Soil Science laboratory in the Obafemi Awolowo
university for support in the analysis of total carbon and TKN
Compliance with ethical standards
Conflict of interest The authors declare that there are no conflic-
ts of interest associated with this study
Open Access This article is distributed under the terms of the
Creative Commons Attribution 40 International License (http
creativecommonsorglicensesby40) which permits unrestric-
ted use distribution and reproduction in any medium provided
you give appropriate credit to the original author(s) and the sour-
ce provide a link to the Creative Commons license and indicate
if changes were made
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 345
References
Adewumi IK Ogedengbe MO Adepetu JA Aina PO (2005) Aerobic composting of municipal solid wastes and poultry manure J appl sci res 1292ndash297
Al-Muyeed A Oko-williams A Islam K Ali L Nath SK Sanyal PR (2017) Co-composting of faecal sludge with solid waste to improve faecal sludge management practice in Sakhipur municipality In Local action with international cooperation to improve and sustain water sanitation and hygiene ser-vices Loughborough pp 1ndash7
Anwar Z Irshad M Fareed I Saleem A (2015) Characterization and recycling of organic waste after co-composting - A re-view J Agric Sci 768 httpsdoiorg105539jasv7n4p68
APHA (1998) Standard methods for examination of water and wastewater 19th edition American public health association Washington DC
APHAAWWAWEF (2005) Standard methods for the exam-ination of water and wastewater 21st edn American public health association American water works association and water and environment federation Washington DC
Bartram J Pedley S (1996) Chapter 10 - Microbiological analy-ses In Bartram J Ballance R (eds) Water quality monitoring - A practical guide to the design and implementation of fresh-water quality studies and monitoring programmes UNEPWHO 27pp Available at httpswwwresearchgatenetpublication253953121_Water_quality_monitoring_a_prac-tical_guide_to_the_design_and_implementation_of_fresh-water_quality_studies_and_monitoring_programmes
Bernal MPP Alburquerque JAA Moral R (2009) Composting of animal manures and chemical criteria for compost maturity assessment A review Bioresour technol 1005444ndash5453 httpsdoiorg101016jbiortech200811027
Brinton W (2000) Compost quality standards and guidelines New York NY United States
Cheng X Wang J Chen B Wang Y Liu J Liu L (2017) Effec-tiveness of phosphate removal during anaerobic digestion of waste activated sludge by dosing iron (III) J Environ Manage 19332ndash39 httpsdoiorg101016jjenvman201702009
Chuah CJ Ziegler AD (2018) Temporal variability of faecal contamination from on-site sanitation systems in the ground-water of northern Thailand Environ Manage 61939ndash953 httpsdoiorg101007s00267-018-1016-7
Cofie O Kone D Rothenberger S Moser D Zubruegg C (2009) Co-composting of faecal sludge and organic solid waste for agriculture Process dynamics Water res 434665ndash4675 httpsdoiorg101016jwatres200907021
Cofie O Nikiema J Impraim R Adamtey N Paul J Koneacute D (2016) Co-composting of solid waste and fecal sludge for nutrient and organic matter recovery Resource recovery and reuse series 3 International water management institute (IWMI) CGIAR research program on water land and eco-systems (WLE)
Costa MSSDM Carneiro LJ Costa LADM Pereira DC Lorin HEF (2016) Composting time reduction of agricultural wastes Eng Agriacutecola 361206ndash1217 httpsdoiorg1015901809-4430-engagricv36n6p1206-12172016
Deacuteportes I Benoit-Guyod JL Zmirou D (1995) Hazard to man and the environment posed by the use of urban waste com-post A review Sci Total Environ 172197ndash222 httpsdoiorg1010160048-9697(95)04808-1
Dias BO Silva CA Higashikawa FS Roig A Saacutenchez-Monede-ro MA (2010) Use of biochar as bulking agent for the com-posting of poultry manure Effect on organic matter degra-dation and humification Bioresour Technol 1011239ndash1246 httpsdoiorg101016jbiortech200909024
Fan Y Chen J Shirkey G John R Wu SR Park H Shao C (2016) Applications of structural equation modeling (SEM) in ecological studies An updated review Ecol Process 519 httpsdoiorg101186s13717-016-0063-3
Fernaacutendez FJ Saacutenchez-Arias V Rodriacuteguez L Villasentildeor J (2010) Feasibility of composting combinations of sewage sludge olive mill waste and winery waste in a rotary drum reactor Waste Manag 301948ndash1956 httpsdoiorg101016jwasman201004007
Galitskaya P Biktasheva L Saveliev A Grigoryeva T Boulygina E Selivanovskaya S (2017) Fungal and bacterial successions in the process of co-composting of organic wastes as revealed by 454 pyrosequencing PLoS One 121ndash20
Gao M Li B Yu A Liang F Yang L Sun Y (2010) The effect of aeration rate on forced-aeration composting of chicken manure and sawdust Bioresour Technol 1011899ndash1903 httpsdoiorg101016jbiortech200910027
Garson GD (2016) Partial least squares Regression and structur-al equation models 2016 edition Statistical associates blue book series 10 Statistical associates publishing 265pp
Getahun T Nigusie A Entele T Gerven TV Bruggen BVD (2012) Effect of turning frequencies on composting biodegradable municipal solid waste quality Resour Conserv Recycl 6579ndash84 httpsdoiorg101016jresconrec201205007
Gold M Dayer P Faye MCAS Clair G Seck A Niang S Mor-genroth E Strande L (2016) Locally produced natural con-ditioners for dewatering of faecal sludge Environ Technol 372802ndash2814 httpsdoiorg1010800959333020161165293
Hanc A Szakova J Svehla P (2012) Effect of composting on the mobility of arsenic chromium and nickel contained in kitchen and garden waste Bioresour Technol 126444ndash452 httpsdoiorg101016jbiortech201111053
IRC (2015) Value at the end of the sanitation value chain Available at httpswwwresearchgatenetprofileSoumya_Balasubra-manyapublication299429922_VeSV-Value_at_the_end_of_Sanitation_Value_Chainlinks5890077f45851573233e8650VeSV-Value-at-the-end-of-Sanitation-Value-Chainpdf
IWMI (International water management institute) and SANDEC (Sanitation in Developing Countries) (2002) Co-composting of faecal sludge and solid waste Preliminary recommen-dations on design and operation of co-composting plants based on the Kumasi pilot investigation 91pp Available at httpssswminfositesdefaultfilesreference_attachmentsIWMI20SANDEC20200220CoComposting20of20Faecal20Sludge20and20Solid20Wastepdf
Jenkins MW Cumming O Cairncross S (2015) Pit latrine empty-ing behavior and demand for sanitation services in Dar Es Sa-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347346
laam Tanzania Int J environ res public health 122588ndash2611 httpsdoiorg103390ijerph120302588
Jeong K-H Kim JK Ravindran B Lee DJ Wong JWC Sel-vam A Karthikeyan OP Kwag JH (2017) Evaluation of pi-lot-scale in-vessel composting for Hanwoo manure manage-ment Bioresour Technol 245201ndash206 httpsdoiorg101016jbiortech201708127
Johansson SAE Thomas B (1976) Analytical application of par-ticle-induced X-ray emission Nucl Instruments Methods 37473ndash516
Kaboreacute TWT Houot S Hien E Zombreacute P Hien V Masse D (2010) Effect of the raw materials and mixing ratio of com-posted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa Bioresour Technol 1011002ndash1013 httpsdoiorg101016jbiortech200908101
Karanja N Kwach H Njenga M (2015) Low-cost composting training manual based on the UN-HABITAT URBAN HAR-VEST-CIP Community based waste management initiatives 37pp Available at httpswwwresearchgatenetpublica-tion319187370_LOW_COST_COMPOSTING_TRAIN-ING_MANUAL
Kone D Gallizzi K Drescher S et al (2004) Efficiency of Hel-minth eggs removal in dewatered faecal sludge by co-com-posting In People-centred approaches to water and en-vironmental sanitation Proceedings of the 30th WEDC conference pp 34ndash38
Krishnan Y Bong CPC Azman NF Zakaria Z Othman NA Abdullah N Ho CS Lee CT Hansen SB Hara H (2017) Co-composting of palm empty fruit bunch and palm oil mill effluent Microbial diversity and potential mitigation of greenhouse gas emission J Clean Prod 14694ndash100
httpsdoiorg101016jjclepro201608118Kwiatek WM Dutkiewicz EM Glebowa L Marczewska E
Sowa M (1994) Sample preparation procedure for PIXE PIGE and RBS techniques applied for biological studies in Henryk Niewodniczanski Institute of Nuclear Physics 76ndash77
Lohri CR Diener S Zabaleta I Mertenat A Zurbruumlgg C (2017) Treatment technologies for urban solid biowaste to create value products A review with focus on low- and middle-in-come settings Rev Environ Sci Biotechnol 1681ndash130 httpsdoiorg101007s11157-017-9422-5
Mandal P Chaturvedi MK Bassin JK Vaidya AN Gupta RK (2014) Qualitative assessment of municipal solid waste com-post by indexing method Int J Recycl Org Waste Agric 3133ndash139 httpsdoiorg101007s40093-014-0075-x
McGranahan G (2015) Realizing the right to sanitation in de-prived urban communities Meeting the challenges of collec-tive action coproduction affordability and housing tenure World Dev 68242ndash253httpsdoiorg101016jworlddev201412008
Mengistu T Gebrekidan H Kibret K Woldetsadik K Shimelis B Yadav H (2018) Comparative effectiveness of different com-posting methods on the stabilization maturation and sanitiza-tion of municipal organic solid wastes and dried faecal sludge mixtures Environ Syst Res 65httpsdoiorg101186s40068-017-0079-4
Morisaki N Phae CG Nakasaki K Shoda M Kobuta H (1989) Nitrogen transformation during thermophilic composting J Ferment Bioeng 6757ndash61
Nartey EG Amoah P Ofosu-Budu GK Muspratt A Pradhan Sk (2017) Effects of co-composting of faecal sludge and agri-cultural wastes on tomato transplant and growth Int J Recycl Org Waste Agric 623ndash36 httpsdoiorg101007s40093-016-0149-z
NBSUNICEF (2017) Multiple indicator cluster survey 2016-17 National Bureau of Statistics and United Nations Childrenrsquos Fund Accessed at httpswwwuniceforgnigeriaNG_pub-lications_mics_201617pdf
Niwagaba C Nalubega M Vinnerarings B Sundberg C Joumlnsson H (2009) Bench-scale composting of source-separated human faeces for sanitation Waste Manag 29585ndash589 httpsdoiorghttpdxdoiorg101016jwasman200806022
Osibote BA Osibote IA Bolaji OM Ana GREE (2016) Effect of thermal treatment on microbial load of faecal sludge from some faecal sludge collection sites in Oyo state south west-ern Nigeria Jordan J Biol Sci 9243ndash248
Otterpohl R Grottker M Lange J (1997) Sustainable water and waste management in urban areas Otterpohl Wasserkonzepte Kanalstraszlige 52 D-23552 Luumlbeck Germany
Oyelami AC Aladejana JA Agbede OO (2013) Assessment of the impact of open waste dumpsites on groundwater quality A case study of the Onibu-Eja dumpsite Southwestern Nige-ria Procedia Earth Planet Sci 7648ndash651 httpsdoiorg101016jproeps201303168
Parkinson R Gibbs P Burchett S Misselbrook T (2004) Effect of turning regime and seasonal weather conditions on nitrogen and phosphorus losses during aerobic composting of cattle manure Bioresour Technol 91171ndash178 httpsdoiorg101016S0960-8524(03)00174-3
Rao K Otoo M Drechsel P Hanjra M (2017) Resource recovery and reuse as an incentive for a more viable sanitation service chain Water Altern 10493ndash512
Scoton EJ Battistelle RAG Bezerra BS Bezerra BS Renoacutefio A Akutsu J (2015) Parameters evaluation of the co-composting of sewage sludge and grass clippings using the respirometric method Int J Environ Waste Manag 16262 httpsdoiorg101504IJEWM2015073034
Scoton EJ Battistelle RAG Bezerra BS Akutsu J (2016) A sewage sludge co-composting process using respirometric monitoring method in hermetic rotary reactor J Clean Prod 121169ndash175httpsdoiorg101016jjclepro201504081
Semiyaga S Okure MAE Niwagaba CB Nyenje PM Kansiime F (2017) Dewaterability of faecal sludge and its implications on faecal sludge management in urban slums Int J Environ Sci Technol 14151ndash164httpsdoiorg101007s13762-016-1134-9
Singh S Mohan R Rathi S Raju NJ (2017) Technology options for faecal sludge management in developing countries Ben-efits and revenue from reuse Environ Technol Innov 7203ndash218 httpsdoiorg101016jeti201702004
Soares MAR Quina MJ Reis MS Quinta-Ferreira R (2017) As-sessment of co-composting process with high load of an inor-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
International Journal of Recycling of Organic Waste in Agriculture (2020)9 333-347 347
ganic industrial waste Waste Manag 5980ndash89 httpsdoiorg101016jwasman201609044
Stefanakis AI Komilis DP Tsihrintzis VA (2011) Stability and maturity of thickened wastewater sludge treated in pilot-scale sludge treatment wetlands Water Res 456441ndash6452 httpsdoiorg101016jwatres201109036
Strande L Ronteltap M Brdjanovic D (2014) Faecal sludge man-agement systems approach for implementation and opera-tion p 403
Strauss M Heinss U Montangero A (2000) On-site sanitation When the pits are full--planning for resource protection in faecal sludge management Schriftenr Ver Wasser Boden Lufthyg 105353ndash360 httpsdoiorg105 353-360
Suess MJ Huismans J (1983) Management of hazardous wastes Policy guidelines and code of practice UNEPWHO
Sundberg C Smaringrs S Joumlnsson H (2004) Low pH as an inhibiting factor in the transition from mesophilic to thermophilic phase in composting Bioresour Technol 95145ndash150
Tiquia SM Wan JHC Tam NFY (2002) Dynamics of yard trim-mings composting as determined by dehydrogenase activity ATP content arginine ammonification and nitrification po-tential Process Biochem 371057ndash 1065
Uggetti E Llorens E Pedescoll A Ferrer I Castellnou R Garciacutea J (2009) Sludge dewatering and stabilization in drying reed
beds Characterization of three full-scale systems in Catalo-nia Spain Bioresour Technol 1003882ndash3890 httpsdoiorg101016jbiortech200903047
Uggetti E Argilaga A Ferrer I Garciacutea J (2012) Dewatering model for optimal operation of sludge treatment wetlands Water Res 46335ndash344 httpsdoiorg101016jwatres201110040
Vergara SE Tchobanoglous G (2012) Municipal solid waste and the environment A global perspective Annual Review of Environment and Resources 37(1) 277ndash309 httpsdoiorg101146annurev-environ-050511-122532
Vinod B Ravindernath A (2015) Compost quality assessment of greater hyderabad municipal corporation (GHMC) India Int J Eng Res Appl 51ndash9
Wang P Zhang H Zuo J Zhao D Zou X Zhu Z Jeelani N Leng X An S (2016) A hardy plant facilitates nitrogen removal via microbial communities in subsurface flow constructed wet-lands in winter Scientific reports 6(1) School of life science Institute of wetland ecology Nanjing University Nanjing China Nature Publishing Group 33600httpsdoi101038srep33600
World Health Organization (WHO) (2010) Third edition of the WHO guidelines for the Safe use of wastewater excreta and greywater in agriculture and aquaculture 12pp
- _Hlk518764994
- _Hlk45484140
- _Hlk45698480
- _Hlk45706904
- _Hlk45698375
- _Hlk45481106
- _GoBack
-
![Bacterial communities and metabolic activity of faecal ... · mination in urine [17]. Briefly, after 24 h incubation, faecal Briefly, after 24 h incubation, faecal cultures were centrifuged](https://static.fdocuments.in/doc/165x107/5c9c009909d3f215138c3813/bacterial-communities-and-metabolic-activity-of-faecal-mination-in-urine.jpg)
