Human feces composting

technology in cold climate2017. 9. 19

B. Shijirtuya,

Environmental Engineering Department,

School of Civil Engineering and Architecture,

Mongolian University of Science and Technology

CASE STUDY ANALYSES OF WASTE-TO-ENERGY PROJECTS

Capital city-Ulaanbaatar 1 151 600

62% of city population living in the ger area

Population of Mongolia 3.119.000

Nation wide

In the ger area 95% of population still using

pit latrine.

Эх үүсвэр:

• МЯНГАНЫ ХӨГЖЛИЙН ЗОРИЛТУУДЫН ХЭРЭГЖИЛТ Илтгэл 2013

• Нийгмийн индикатор түүвэр судалгаа

• ACF KAP судалгаа 2012-2014

Problem of pit latrine

- Soil pollution

- Ground water pollution

- Flooding

- Uncontrolled private well

Sanitation issue in UB ger area

A crucial problem for the ger area inhabitants

But a problem also for the city of Ulaanbaatar, and for the future of Mongolia

Several important issues :

Environment

Hygiene

Particular conditions :

No water connection

Harsh climate

Cultural and social difficulties

20/08/2013

6

Jé rô me Vassal - UB ACF dry toilets composting project

ACF is International humanitarian NGO who implemented WaSH project in UB.

A very good investment from the staff of ACF

Several testing and adaptations :

sealed pits

urine diversion systems

ventilation

distribution of sawdust

emptying every 3 months

composting

20/08/2013

7Sanitation issue in UB ger campsSanitation issue in UB ger camps

Jé rô me Vassal - UB ACF dry toilets composting

project

Human feces:

• Treatment technology

Thermophillic compoating:

Treatment Technology of Human Feces сонголтAround 50kg per year

10% - N30% - P25% - K

107-9 pathogen

- Biogas- Biochar- Composting- Incineration etc,

Thermophilic composting is the practice of breaking down biological waste with thermophilic (heat-loving) bacteria. The key advantage of thermophilic composting is that the high temperatures kill diseases.

microorganismExcreta + О₂ СО₂ + Н₂О + Heat + Compost

The key advantage of thermophilic composting is that the high temperatures kill diseases. All the organisms that cause human diseases are adapted to live around human body temperature. Higher temperatures kill them. The bacteria that make compost need oxygen.

Excreta lab analyses

Type of analysisDry

MatterOrganic Matter

Heavy Metal pollutantCd Cr Cu Hg Ni Pb Zn Se

Number of analysis 17 17 16 16 16 16 16 16 16 16

Type of analysisMicro pollutants Bateriological test

Other PCB Helminth eggs Listeria Salmonella OtherNumber of analysis 54 126 8 8 8 24

Type of analysisAgriculture parameters

Na2O SO3 pH N C N(NH4) P2O5 K2O CaO MgONumber of analysis 15 15 15 15 15 15 15 15 15 15

18 toilet samples 540 chemical and bacteriological tests

0% 20% 40% 60% 80% 100%

ACF ECOSAN

(A)

ACF ECOSAN

(B)

ACF RAISED (C)

ACF RAISED (D)

ACF RAISED (E)Organic matter (% Dry

matter)

UDDT

• Dry matter 20% (average)• Organic matter 80-90% (average)

Study area – Ecological sanitation cycle

ACF-Mongolia constructed 300pcs urine diverting dry toilets in ger area of UB city. Dry toilet model adapted to the Mongolian cold climate. The

urine doesn’t collected due to freezing during 7 months. Fecal matter

collected in the boxes. Every 3 months collection service remove filled

boxes and switch empty box.

ЭкоСан цикл

Emptying service• Composting facility

Emptyable UDDT

Winter composting facility

Canadian well and ERV

systems ensure heating

and air circulation of

composting facility

Compost facility

16 dé cembre

2017-30℃

0℃

12℃

S/

N

Parameters Reasonable Range Preferred Range

1 C/N ratio 20:1-40:1 25-30:1

2 Moisture content (%) 40-65 50-60

3 Oxygen concentration (%) 5 Much > 5

4 Particle sizes (Inches) 1/8-1/2 Varies

5 pH 5.5-9.0 6.5-8

6 Temperature (°C) 43-66 54-60

Methodology

Bin Feces/woodsawdust

ЕМ1 EM2 Straw Woodsawdust

1 1 1 0 1 0 0

2 1 1 1 0 0 0

3 1 1 0 1 1 0

4 1 1 1 0 1 0

5 1 1 0 1 0 1

6 1 1 1 0 0 1

7хян 1 1 0 0 0 1

(1-added, 0-no added)

Bin 1: ЕМ2 Weight(kg) H2O(kg)Dry

mass(/kg)Weight-C Weight-N

Feces / sawdust

mixed18 9.6782 8.3218 4.284 0.18

Total 18 9.68 8.32 4.28 0.18

H2O%=54% C/N=24

Bin 2: ЕМWeight(kg

)H2O(kg)

Dry

mass(/kg)Weight-C Weight-N

Feces / sawdust

mixed18 9.6782 8.3218 4.284 0.18

Total 18 9.68 8.32 4.28 0.18

H2O%=54% C/N=24

Bin 3: ХЕМWeight(kg

)H2O(kg)

Dry

mass(/kg)Weight-C Weight-N

Ялгадас / үртэс

хольсон12.5 6.721 5.779 2.975 0.125

Сүрэл 1.2 0.0881 1.1119 0.576 0.006

Нийт 13.7 6.8091 6.8909 3.551 0.131

H2O%=50% C/N=27

2 3 41 5 6 7

C:N ~ 30:1

Чийг 40-65%

рН 5.5-8

Analyses:

Figure 3: Interaction of

reactor and surrounding

temperature

Figure 3 shows clearly: if the surrounding temperature declines sharply during a high temperature period in the composting

process, there is also a significant impact on the reactor temperature.

If there is enough organic material in the reactor, and the surrounding temperature is improving again, the reactor

temperature could recover in 1~2d. But if there is not enough organic matter in the reactor or cool temperatures continue, the

reactor temperature is difficult to restore. Figure 4 presents the differences in temperature between the reactor temperature

and surrounding temperature, indicating that the composting process took about 30 days.

Figure 4: Difference in temperature between reactor and surrounding

Figure 5: Effects of different additives

Figure 5 demonstrates the effects of different additives.

In three reactors the highest temperature was 65° C,

61° C, and 56° C respectively. Temperature was

maintained above 50° C through 9d, 9d, 5d respectively.

Temperature was maintained above 45° C through 16d,

17d, 18d respectively thus achieving the die-off of

pathogens.

Reactor #1 - using sawdust - had a relatively slow

startup, but this reactor achieved the highest

temperature at 65° C. One reason could have been that

the coarse size of the sawdust is very small, and makes

air convection difficult. Under these conditions it is

difficult for the microbial to obtain sufficient oxygen for

the decomposition of the organic matter, but it is easy to

keep warm.

Reactors #3 and #5, where straw and wood chip had

been applied as additive, showed a relatively fast

startup; a reason for this development could be found in

the coarse size of straw and wood chips which is big,

thus making air convection easy. On the other hand,

these 2 reactors were easy influenced by changes in the

surrounding temperature.

Results 16

déce

mbre

2017

17

t°

Maximum temperature of every reactor Red – number of days over 55̊С Orange – number of days over 45̊С

Country Temp Time Source

China 50-55 5-7

days

Standard (GB

7959-87)

WHO 50 ≥ 5 WHO, 2006

Germany 55/65 14/7 BioAbfv, 2006

Indoor experimentReceipt moisture% C% N% weight(/kg) dens. (kg/l) vol. (l)

feces[1] 77.0 9.8 1.6 180.00 1.00 180

sawdust[2] 3.5 35.0 0.1 36.00 0.15 240

straw[2] 1.5 55.0 0.4 9.60 0.04 240

Moisture content: 62.1%

Total volume 660lC:N ratio 29:1

Specification:• Winter time, indoor

• Ambient temperature

100С

• Total volume 660l

• Ventilation system

• Gas discharging pipes

• Pipe for extra liquid discharge

Results August trail 2011:

Analyses

Compost

total

temperature

>55°С

number

of days

>65°С

number

of days

Reactor 1

96548.0°С 13 10

Reactor 2

85381.0°С 10 2

Reactor 3

98994.5°С 15 9

Bin 1

Bin 2

Bin 3

Temp curve

Countr

y

Temp Time

China 50-55 5-7

WHO 50 ≥ 5

Germa

ny

Austria

55/65

60/65

14/7

6/3

Monitoring

- Every hour temp log

- Every day рН log

- Every day moisture and

gas release

Lab test

DateSample

number

Sample

name

Fecal

coliform

Salmonell

a/

Shigella

Helmint egg

Giardia/

Cryptosporidiu

m

Rotavirus/

Adenovirus

01.22

T-1 7 days,

түүхий

ялгадас, үнэр

багатай

log 3.04

Not

appeared

Not

appeared

Cryptosporidiu

m found

Not

appeared

T-2Not

appeared

Cryptosporidiu

m found

Not

appeared

T-3Not

appeared

Not

appeared

Cryptosporidiu

m found

Not

appeared

01.29

T-414 days,

өттэй,

хүрэн өнгөтэй

log 1.86

Not

appeared

Not

appearedNot appeared

Not

appeared

T-5Not

appeared

Not

appearedNot appeared

Not

appeared

T-6Not

appeared

Not

appearedNot appeared

Not

appeared

02.07

T-7

21 days,

хүрэн өнгөтэй

log 1.89

Not

appeared

Not

appearedNot appeared

Not

appeared

T-8Not

appeared

Not

appearedNot appeared

Not

appeared

T-9Not

appeared

Not

appearedNot appeared

Not

appeared

02.14

T-10

28 days,

хүрэн өнгөтэй

log 1.86

Not

appeared

Not

appearedNot appeared

Not

appeared

T-11Not

appeared

Not

appearedNot appeared

Not

appeared

T-12Not

appearedNot appeared

Not

appeared

0

0.5

1

1.5

2

2.5

3

3.5

7 хоног 14 хоног 21 хоног 28 хоног

1-хутгалт 2-хутгалт 3-хутгалтхоног

Log/gEPA guideline

Parameters - Fecal coliform

- Salmonella.spp,

- Shigella.spp

- Adenovirus,

Rotavirus

- Helmint egg

- Giardia

Cryprosporidium

Fecal Coliform-ийн үзүүлэлтийг

АНУ-ын Хүрээлэн буй

орчныг хамгаалах агентлагийн зөвлөмжтэй

харьцуулсан дүн

Color: black brownOdor: wet soilVisually: not compose all additives such like straw

Compost

After 30days compost visual test

After 30 – 40 days

Final product after 3 months

Final Product Compost

Reactor рН Moisture

%

Total N% Organic

C,%Р₂О₅ % К₂О, %

№1 6.5 40.12 2.63 89.94 2.43 0.45

№2 6.66 49.08 2.39 89.64 2.08 0.27

№3 6.64 45.72 2.37 85.86 1.99 0.21

Thank you for your attention