Citation:Fletcher, IA (2016) An effective approach for the management of waste coffee grounds. In: In-ternational Sustainable Ecological Engineering Design for Society (SEEDS) Conference 2015, 17September 2015 - 18 September 2015, Leeds Beckett University.

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ISBN: 978-0-9955690-0-3

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ANEFFECTIVEAPPROACHFORTHEMANAGEMENTOFWASTECOFFEEGROUNDS

IanAdrianFletcher,TheLeedsSchoolofArchitecture,LeedsBeckettUniversity,SchoolofArtArchitectureandDesign,Leeds,LS29EN,UnitedKingdom.

Keywords:ResourceRecovery,SustainableWasteManagement,Coffee,VermicompostingandEarthworms.

ABSTRACT

In recent years the disposal of organic wastes from domestic, commercial, agricultural and industrialsourceshavecausedconcernsduetotheenvironmentalandeconomicproblemsassociatedwithwaste.Thewaste produced particularly in urban areas represents a huge cost for cities and a burden to theenvironmentbut,at the same time, representsanopportunity to take stockof valuable resources,whichcanbeexploited.Byboostingsolutionstoreducewasteandpromotingitsuseasaresourcethenaturalandlivingenvironmentinurbanareascanbeenhanced.Citiesarecomplexsystemssimilartolivingorganismsthatuseenergy,air,waterandnutrientsandneedtodisposeofwasteinasustainableway.Byadoptinganurbanmetabolism perspective cities can open theway for innovative and systematic approaches, whichinvolve the analysis and use of resource-flows. Waste coffee grounds represent an under-utilised highnutrientmaterialwithpotentialtobeexploited.Coffeeisregardedasthehighestconsumedbeverageinthedevelopedworld,and is thesecondmost tradedcommodity in theworldafteroil.Thispaperwillpresentresearchfindingsforaneffectiveapproachforthemanagementofwastecoffeegrounds.This isachievedthrough examining an alternative approach of resource recovery and sustainable waste managementpracticesforwastecoffeegrounds. Itwillalsouseacasestudytoexaminethepotential forwastecoffeegroundstopromoteanecologicalrethinkingofnutrientflows.

1. INTRODUCTIONSince the Industrial Revolution, industrial production and urbanisation have constantly increased, usingmassive amounts of materials, water and energy. The mass consumption of resources contributes toseriousproblems,suchasglobalwarming,materialdepletionandthegenerationofenormouswaste.Itiswidely accepted that the United Kingdom will have to deliver significant improvements to its wasteinfrastructureoverthecomingdecadesinordertosuccessfullyrecycle,reprocess,treatanddisposeofitswaste.Inthemetabolismofthecity,Lehmann(2012),definessustainableurbanmetabolismasavisionofindustrial organisation that applies the lessons of natural ecosystems to environmental management,wherewastefromoneprocessbecomesinputsandopportunitiesforanother(Lehmann&Crocker,2012).According toanewstudypublishedby theDepartmentofEnvironment,FoodandRuralAffairs (DEFRA),resource efficiency could generate an extra £3.58bn for UK businesses by 2020 (DEFRA 2015). Wastegeneration is anaturalphenomenonand theamountofwasteproducedcanbedirectlyassociatedwithchanges incultureandthewayof life.Thesechangesbringwiththemahugequantityofcomplexwastestreams, which contains considerable amounts of nutrients, which have the potential to be recycled.Rethinking thewaywedealwithmaterial flowsand changingbehaviour in regard towaste streams cancontribute to significant improvements for curbing environmental degradation and global warming(Lehmann & Crocker, 2012). In his argument for "the economics of permanence," Schumacher (1973)impliesaprofoundreorientationof scienceand technology is required.Emphasisinganeed formethodsand equipment, which are cheap and accessible to virtually everyone, and also suitable for small-scaleapplication.Atpresent, notonly is it virtually impossible to know the trueenvironmental andecologicalimpact of theproductswe consume, but also theorigins, theprocessesofmanufacture and the cost oftransportation. Kimbrell (2002) argues, that the distance between the consumer and production hascreated a tragic disconnection of the environmental consequences of production and consumption.Tompkins (2002)describes itasaculturalcrisis rooted inthetransformationfromanessentiallyagrarianculture to one that's completely industrialised. It is clear that a holistic understanding and integratedapproach to design and urbanmanagement are essential for the effective resolution of urbanwaste. Inpresentcircumstancesitisadvisablethatwasteproductsfromoneindustryshouldbeinvestigatedwithanintentiontobeusedasrawmaterialsforotherindustries.

Therapidexpansionofglobalcoffeeconsumptionincreasedfrom4.2milliontonnesin1970to8.1milliontonnesin2010,anincreaseof91percent.Withconsumptiongrowingby12percentinWesternEuropeanmarkets (ICO,2011). In2014, thecoffeeshopmarketoutperformed theUK retail sector,withsignificantsalesgrowthof10.7%,equatingto£7.2billioninturnover.Thecoffeeshopsectorhasbeeningrowthfor16 consecutive years and is one of the most successful markets in the UK economy (Foottot, 2014).AccordingtotheAllegraWorldCoffeePortaldefinitivereport,theUKcoffeemarketisestimatedat18,832outletsandpredictedtoexceed27,000by2020(Foottot,2014).IntheUnitedKingdomcoffeeconsumptiontakevariousforms,includingsolubleandfiltercoffee.Thepreparationofthebeverageandthelocationofconsumptionarelargelyinfluencedbynationalculture.However,coffeegrounds(filtercoffee)areasingleuseproductandthetotalwastegeneratedfromthedisposalofcoffeeisequaltoallimportsandsales.Theenvironmental impacts of coffee are enormous, with large quantities of solid and liquid wastes beinggenerated globally (Roussos et al., 1998; Hue et al., 2006; Liu et al., 2011). This is due to the dramaticchangeofcultivationmethods.Coffeeiscultivatedintropicalandsubtropicalregionsathighelevationsandnaturallygrowsunderashadedcanopyoftrees,whichprovideavaluablehabitat for indigenousanimalsandinsects,aswellaspreventingtopsoilerosionanderadicatestheneedforchemicalfertilisers.However,due to the increased market demands in recent years, this innocuous form of agriculture has beensupersededbysun-cultivation techniques.Originating in the1970’s, sun-cultivatedcoffee isproducedonplantations,where forestry is cleared so that coffee is grown in rowsas amonoculturewithno canopy.Coffee farmerswereencouraged to replace their traditional and supposedly inefficient farmingmethodswiththehigheryieldingtechniques,whichresultedindeforestation(Moore2014).Inalifecycleanalysisofcoffee, Salmone (2003) reported cultivation and consumption of coffee as the two largest contributorstowards negative environmental impacts (Liu & Price 2011). The process of separating the commercialproduct(thebeans)fromthecoffeecherriesgeneratesenormousvolumesofwastematerialintheformofpulp, residualmatter and parchment. Over a 6month period in 1988, it was estimated that processing547,000 tons of coffee in Central America generated as much as 1.1 million tons of pulp and polluted

110,000cubicmetresofwatereachday.Thisexcesswastecanalsoplayhavocwithsoilandwatersourcesascoffeepulp isoftendumped intostreams,severelydegradingfragileecosystems(Moore2014). IntheUnitedKingdomaverageannual importsduringtheperiod1997to2010totalled3.4millionbags.Amongthe ten leading countries supplying coffee to the United Kingdom, re-exports from other importingcountries, Germany (13.6%), Netherlands (7.6%), Spain (4.1%), Ireland (2.4%), France (2.3%) and Italy(2.1%), accounted for 32.2% of the total compared with 41.2% coming from exports by Vietnam (14%)Brazil (11.7%), Columbia (9.4%) and Indonesia (6.1%), (ICO, 2011). In the United Kingdom, the wastegeneratedfromtotalimportofcoffeegroundsareeitherlandfilledorprocessedatmunicipalfacilitieswithotherorganicwastes.Coffeeconsumption inacitycantakevarious forms; thisstudy is interested intheout-of-home market and the location of consumption. It covered those food service establishments inLeedswherecoffee is served.Of the5,067 foodbusinesses registeredunder the localauthorityofLeeds(Leeds City Council, 2015), 1892 are registered to serve coffee (Food & Health, 2014). The beveragemaintainsasocialcharacterinthecityasconsumptioniswidelydistributedacrossbars(176outlets),café(557), canteens (168),pubs (371), restaurants (387)andvarious leisurecentres (248) seeFigure1.CostaCoffeeholdsadominantshareof thebrandedmarket inLeedswithatotalof17outlets.WhitbreadPLCevaluatedwaste generatedbyweight for their Costa chain stores and found that organic food& coffeegrinds was the biggest contributor of waste produced followed by paper waste at 65.7% and 21.2%respectively (Costa, 2012).With the average Costa chain store producing approximately 20kgs of wastecoffeegroundsperday (Gourlay, 2014). Thisprovidesanenormousopportunity forwastediversionandresource recovery in the cityof Leedswith the city generating approximately 38 tonnesofwaste coffeegroundsperday.

Figure1.DistributionofcoffeeconsumptioninLeeds.

Waste coffee grounds represent an under-utilised high nutrientmaterial with potential, as compost forhorticulturalusethereforerecyclingthroughvermicompostingcanbeasustainable,lowcostalternativetodisposal. The available literature on vermicomposting waste coffee grounds is limited but some studieshave evaluated its use as a horticultural amendment, as a mushroom growing medium, as compostfeedstock, and as biofuel feedstock (Liu & Price, 2005; Barreto et al., 2008; Kondamudi et al., 2008).Composting technologies have been widely applied to transform raw organic feedstock into stabilisedhumus-likematerials(Liu&Price,2005;Tiquiaetal.,1996).Thebiotransformationprocessismediatedbymicrobial biomass under idealised moisture, oxygen, pH, carbon (C) and nitrogen (N) conditions.Vermicomposting has been used to process awide range of feedstocks, including coffee pulp, livestockmanures,andfoodwastes (Liu&Price,2005;Lopez,2001).Earthwormscanplayasignificantrole in themanagementofwastecoffeegrounds.Therearemanyspeciesofearthwormswiththepotentialforwastemanagement,but themost commonlyusedareE.fetida, andE.hortensis. Theyareubiquitousandmanyorganicwastesarenaturallycolonisedbythespecies.Theycantolerateawiderangeoftemperaturesandliveinorganicwasteswithagoodrangeofmoisturecontents(Edwards&Bohlen,1996).Theaimsofthestudy are to evaluate the use of vermicomposting biotechnology as a viable option for the diversion ofwastecoffeegrounds.

2. METHODS

2.1. VERMICOMPOSTING

Vermicomposting is a decomposition process involving interactions between earthworms andmicroorganisms. Although the microorganisms are responsible for the biochemical degradation of theorganic matter, earthworms are the crucial drivers of the process. They fragment and condition thesubstrate,increasingsurfaceareaformicrobiologicalactivityandalteringitsbiologicalactivity.Earthwormsactasmechanicalblenders,andbycomminutingtheorganicmatter,theymodifyitsbiological,physicalandchemical status, gradually reducing its C:N ratio, increasing the surface area exposed tomicroorganismsandmakingitmuchmorefavourableformicrobialactivityandfurtherdecomposition(Domínguez,2004).Vermicompostingsystemsaredesignedtomaintainconditionsfavourabletothemostrapiddecomposers,the mesophilic bacteria. The combination of earthworms and mesophilic bacteria are used to rapidlystabilisetheorganicchemicalcompounds,reducingthelossofvaluablenutrients.

2.2. VERMICULTUREPROJECT

The Vermiculture Project was established as a bio-technological social enterprise to help coffee shopsoperatinginthefoodservicesectorinLeedstransitiontowardszerowaste.Theaimsaretoprovidelandfilldiversionand resource recovery services for coffee shopsand toevaluate thepotential forwaste coffeegroundstobebio-transformed intoastabilisedhorticulturalcompost foruse inorganic foodproduction.Onthe22ndSeptember2014theprojectstartedalandfilldiversionandresourcerecoveryservicefortwoofLeedsBeckettUniversityerecoveryservicesforcoffeeshopsandtodHeadingleycampuses.Thewastecoffee grounds are collected daily along with shredded paper and are being recycled using thevermicomposting experiment. The experimental project adapts four replications of the “Oregon SoilCorporation Reactor”. The vermiculture compost system is a continuous-flow vermicomposting bin. Theoriginal concept for the continuous-flow system was devised by a team of researchers at RothamstedExperimental Research Station, UK in the early 80’s. The concept takes advantage of the fact thatcompostingwormstypicallyprefertoremainquiteclosetothesurfaceofwhatevermaterialtheyhappento be living in,generally moving towards the mostrecently added organic wastes, leaving higherconcentrations oftheir castings behind. The vermiculture compost bins measure 1220mm in length by915mmwideby915mminheightandare locatedinashadetunnelattheLandscapeResourceCentre&ExperimentalGardens(LRC),LeedsBeckettUniversity,HeadingleyCampus,Leeds.Theexperimentalstudyisbeingconductedovera12-monthperiod.

2.3. BIN1&BIN2

The bins were constructed using 18mm thick marine plywood and insulated with 25mm thick CelotexTB4000 insulationboards toprovideadditional insulation for compostingduring thewinterperiod. Theywereloadedonsiteonthe3rdofOctober2014withathinlayerofnewspaper.Thisisdonetoabsorbanyextramoistureand to restrainmigratingearthworms fromescaping into theharvestchamber.Bin1wasloaded with 30kg of waste coffee grounds, pre-composted for 21 days and Bin 2 with 30kg of freshlycollectedwastecoffeegrounds(nopre-composting).The21daysofpre-compostingorganicwasteisdonetoavoidexposureofearthwormstohightemperaturesduringtheinitialthermophilicstageofcomposting(Adi et al., 2009; Nair et al., 2006). It is also done to provide a readily available food source duringinoculation becausemicroorganisms constitute an important nutritional component to the earthworm’sdiet(Edwards&Bohlen,1996).Inbothbins3.4kgofshreddedpaper,5litresofwaterand1kgofE.fetidawasadded,andonthe6thofMarch2015anadditional2kgE.fetidaand2kgE.hortensiswasaddedtobothsystems.

2.4. BIN3&BIN4

The bins were constructed using 18mm thick marine plywood and insulated with 65mm polypropyleneinsulationfoamboards.Theywereloadedonsiteonthe6thofMarch2015,withathinlayerofnewspaper,35kgofpre-compostedwastecoffeegrounds(60days),1.7kgofshreddedpaper,3litresofwater,and2kgof E. fetida and 2kg of E.hortensis. The aims of the experiment are to evaluate the potential for wastecoffee grounds, which are high in nitrogen (Adi et al., 2008; Dinsdale et al., 1996) to be decomposedthrough vermicomposting. Also to assess a vermicomposting system inoculated with a mixed colony ofearthworm species, E.fetida and E.hortensis for transforming waste coffee grounds into a stabilised

horticulturalcompostforuseinfoodproduction.Theexperimentalstudyevaluatestwodifferentratiosofwastecoffeegrounds(WCG)toshreddedpaper(SP),todeterminetherateofwasteprocessingforwastecoffeegrounds (kg/m3bed/week) for aprocessing systemoperatingunderUK conditions. Theobjectivesaretoanalysemoisturecontent,temperature,andpHlevelsofthevermicompost,andmeasurechemicalcharacterisationofthecompostingfeedstockagainstcastproducedbytheearthwormstodetermineplantmacroandmicronutrients

3. RESULTSANDDISCUSSIONS3.1. TEMPERATURE

Temperatureisthemostimportantfactoraffectingmicrobialmetabolismduringcomposting.Itiseitheraconsequenceoradeterminantofthemicrobialactivity.(Vallinietal.,2002)Itisanimportantparameterinmonitoring the composting process and determining compost quality. It is also strongly correlatedwithmicrobialactivityandinrelationtocompostingstagesisusedtodeterminetheconditionssuitablefortheproliferationofdifferentmicrobialgroups,i.e.mesoandthermophiles(Liuetal.,2011;Tiquiaatal.,1996).The composting stages based on temperature, mesophilic, thermophilic, pre-composting, and ambienttemperatures are clearly displayed for the four-replication vermicomposting experiment in Figure 2.Decomposition usually occurs in three stages characterised by themost active organisms. Psychrophilicbacteriabegintheprocessattemperaturesbelow21°C,whichwasobservedonday7bythecolonisationofmicrobialactivitytotheundersideofthenewspaperbeddingseeFigure3.Apeaktemperatureof12gure3n three stages characterised by themost active organisms. Psychrophilic bacteria begin the process attemperatures below 21°C,whichwas observed on day 7 by the colonisation ofmicrobial activity to theunderside of thnompost temperature in Bins 1 (30°C), 2 (22°C), 3 (30°C) & 4 (33°C) on day 14. Attemperaturesover38°Cthermophilicbacteriatakeoverandthepresenceofthebacteriawasalsoevidentfromcomposttemperaturesonday18inBins1(45°C),3(48°C)&4(46°C)whichsignaledthethermophilicstageofdecomposition.However,apeaktemperatureof50°Cwasrecordedonday25inBin1,afterwhichtemperaturesgraduallywaned towardsa rangeof30°Conday28.Theambient temperatureduring thecomposting period from 6 Mar 2015 to 7 April 2015 averaged 7.7°C, and ranged from 1 to 15°C. Thedifferent species of earthworms’ response to temperature differentials during the study period wasobservedanditwasfoundthatE.fetidaweremoretoleranttodifferentialtemperaturescomparedtothatof E.hortensis. The difference between the 21 & 60 days pre-composting of waste coffee grounds andtemperature was marginal. However, in the no pre-composting bin low temperatures were recordedthroughoutthestudyperiod,onlyreachingapeaktemperatureof35°Conday25andcompositingthroughpsychrophilicandmesophilicstagesofdecompositiononly.

Figure2.Changesindailyaveragetemperatureduringtheperiod6Mar.2014to3Apr.2015.

Bin1 Bin2 Bin3 Bin4

30kgofpre-compostedwastecoffeegrounds(21

days)

30kgoffreshlycollectedwaste

coffeegrounds(nopre-composting)

35kgofpre-compostedwastecoffeegrounds(60

days)

35kgofpre-compostedwastecoffeegrounds(60

days)

3.4kgofshreddedpaper

3.4kgofshreddedpaper

1.7kgofshreddedpaper

1.7kgofshreddedpaper

3kgofE.fetida+

2kgE.hortensis

3kgofE.fetida+

2kgE.hortensis

2kgofE.fetida+

2kgE.hortensis

2kgofE.fetida+

2kgE.hortensis

5litresofwater 5litresofwater 3litresofwater 3litresofwater

Thinlayerofnewsprint

Thinlayerofnewsprint

Thinlayerofnewsprint

Thinlayerofnewsprint

Table1.Summaryofinoculationcontentsforeachvermicompostingbin.

Figure3.Microbialactivityrecordedonday7ofvermicompostingexperiment.

3.2. MOISTURE

Moisture is of crucial importance in maintaining microbial activity within a composting matrix becausedecomposition slows dramatically in mixtures fewer than 40% moisture (Domstguez 2004). There arestrongrelationshipsbetweenthemoisturecontents inorganicwasteandthegrowthrateofearthworms(Dom04guez, 2004). In vermicomposting systems, the optimum range of moisture contents for mostspecies has been reported to be between 50 and 90% (Dom00guez 2004; Edwards 1998). E.fetida cansurviveinmoisturerangesbetween50and90%(Dommsguez2004;SimsandGerard1985;Edwards1998)butgrowsmorerapidlybetween80and90%inanimalwastes(Dom04guez2004;Edwards1998).Reineckeand Venter (1985) reported that the optimum moisture content for E. fetida was above 70% in cowmanure. The average moisture content of compost in Bins 1 and 2 was recorded at 73% and 74%respectivelyduring the compostingperiod from3October2014 to3April 2015.Bothbins recorded thelowestmoisturecontentof10%onthe9Jan2015,seefigure5.Priortothisthesystemwasleftidleforatwo-weekperiodduetotheholidayseason(norecordsobtainedduringthisperiod).Itwasobservedthatearthworms and microbial activity had dramatically slowed during this time. However, the choice ofshredded paper provided a hospitable living environment for the earthworms. Earthworms usuallyconsumetheirbeddingasitbreaksdown,andit is importantthat it isaslowprocess,as itwasobservedthatheatingoccursinthefoodlayers(wastecoffeegrounds)ofthevermicompostingsystemandnotinthebedding.Thechoiceofshreddedpaperprovidedtheearthwormswithahighabsorbencymaterial,whichabsorbedandretainedmoisture,allowingthewormsanenvironmenttothrive.Thiswasevidentaftertheholiday season because worms were found in the high-absorbency material and survive the period of

reducedmoisture.

Figure5.Changesinmoisturecontentofcompostduringtheperiod3Oct.2014to3Apr.2015.

3.3. PHMost species of epigeic earthworms are relatively tolerant to pH, but when given a choice in the pHgradient,theymovedtowardsthemoreacidmaterial,withapHpreferenceof5.0.However,earthwormswill avoid acidmaterial of pH less than 4.5, and prolonged exposure to suchmaterial could have lethaleffects (Domtguez2004;EdwardsandBohlen1996). It iswidelybelieved thatwastecoffeegroundsareacidic but as the study clearly displayed consistent pH values around neutral (7.0) were recordedthroughout theexperiment. In general, thepHofwormbeds tends todropover time,however, thepHvaluesrecordedatthestartoftheexperimentwasrecordedat7.0whichhasbeenconsistentlymaintained.MicrobesdrivingcompoststabilisationoperatebestintherangeofpHsbetween6.5and8.0(Vallinietal.,

2002) and as waste coffee grounds are neutral it represents a valuable feedstock which can sustainmicrobesforcompoststabilisation.

3.4. C:NRATIO

Theratioofcarbontonitrogen(C:Nratio) inorganicmatteraddedtosoil isof importance,becausenetmineralisationoftheorganicmatterdoesnotoccurunlesstheC:Nratioisoftheorderof20:1orlower.Earthwormscanhavemajorinfluencesonnutrientcyclingprocessesinmanyecosystems.Byturningoverlarge amounts of organic matter, they can increase the rates of mineralisation of organic matter,convertingorganicformsofnutrientsintoinorganicformsthatcanbetakenupbyplants(Edwards,1996).In themanaged compost operation special attentionwas paid to the ratio of carbon to nitrogen in thewasteandmoisturelevelsofthematerialasitbrokedown.Theratioofwastecoffeegroundstoshreddedpaper(WCG:SP)usedwasaimedatgeneratingcompostwithaC:Nratioof20:1orlower.Aweeklyfeedingprogramwasadaptedfortheexperimentusing19kgWCG:5kgSPforBins1&2and19kgWCG:2.5kgSPforBins3&4.Onthe31stMarch2015,1kgoffinishedcompostwasharvestedfromBins1&2andsentforchemicalanalysis.Analysisofthecompostcompositionhasnotyetbeencompletedbutwillbepublishedatalaterdate.

CONCLUSION

Inrecentyears,vermicompostinghasemergedasasimple,easilyadaptableandeffectivebiotechnologyforrecyclingawiderangeoforganicwastesforagriculturalproduction.Thetechnologyisadvantageousoverthermophilic compost because it contains a considerable amount of organic acids, such as plant growthpromoting hormones and humic acids. It also has high water holding capacity, low C:N ratio and lowphytotoxocity(Pant&Wang,2014).Theinitialresultsofthisstudyindicatethatwastecoffeegroundshavethe potential to be vermicomposted as a primary feedstock. It foundmethods of inoculation for Bin 1loadedwith 21 days of pre-compostedwaste coffee groundsmore effective thanBin 2 loadedwith thenon-pretreatedwaste.Inrelationtomicrobialactivityandcompostingstages,thestudyfoundconditionsinBin1morefavourablefordecomposition.Bin1compostedthroughallthreestagesofdecompositionwithanactivepopulationofpsychrophilic,mesophilic,andthermophilicbacteria,whiletheconditionsinBin2wereonlyfavourableforpsychrophilicandmesophilicbacteria.Bin1containedthemostactivepopulationofmicroorganismsandwasabletobreakdownthewastecoffeegroundsatamuchfasterratethanBin2.Bin1processed12.25kgofwastecoffeegroundsmorethanBin2atarateof6kg/0.375m3bed/week. Inthe 30 weeks of landfill diversion and resource recovery the experiment successfully recycled andprocesseda totalof595kgofwastecoffeegroundsand55kgof shreddedpaper,ataprocessing rateof20kg/1.5m3bed/weekproducingzerowaste.

Togainatrueunderstandingofthepotentialthatexistsforvermicomposting,itisimportanttolookatthe‘BigPicture’.Currently,wastecoffeegroundsaremixedinwithgeneralwasteanddisposedofinageneralcollectionbin.Businesses contractprivatewastemanagement companies for thedisposalof theirwasteandchargesdependonsizeandfrequencyoftheircollection.Thesechargesincludetherentalofcollectionbinsandadutyofcarecharge.Thetruecostisonlyestablishedwhencontractsaresetupwiththewastemanagementcompany.However,WRAPestimatesthatwastecostsbusinessesinthefoodanddrinksupplychain approximately £4 billion annually, with the sector producing 4.1million tonnes ofwaste per year(WRAP,2013).Businessesarebeingplacedunderincreasingpressuretoreducetheiroverallrateofwastetomeet UK and EU limits on the amount of biodegradablemunicipal waste sent to landfills. Currently,thereare1892 food serviceestablishments registeredunder the local authorityof Leeds to servecoffeeandthereexistsanopportunitywithinthecityforthewastestreamtobediverted,recoveredandrecycledusing thebiotechnology. Estimates reveal that approximately 266,000kgofwaste coffee grounds canberecovered within the city weekly and made available as a primary feedstock for vermicomposting. Ifmanagedproperlythewastestreamcancontributetohelpingbusinessesmeettargetsontheamountofbiodegradable municipal waste being sent to landfill. Vermicomposting can provide an opportunity forwaste generators to divert their waste into local communities for beneficial uses, such as organicallyproduced compost for organic food production. Currently only 4.2% of the UK farmland is organicallymanaged,whichisequivalentto738,700hectares.Thestudyrevealsthatthereisanexistingopportunityfor waste coffee grounds to be sustainably managed using vermicomposting on a commercial level atcentralised sites. An estimated 266 tonnes of waste coffee grounds can be sustainably managed and

processedatarateof266,000kg/19,950m3bed/weekusingawormpopulationofapproximately53,200kgof E.fetida and E.hortensis to organically produced compost. The biotechnology can contribute tosignificantimprovementstoexistingwasteinfrastructureandalsobeusedasaresourcetobridgethegapbetweenwaste andorganic foodproduction.Our findings also indicate anopportunity exists for furtherresearchintotheuseofwastecoffeegroundsasanalternativeforrenewableenergyproduction(biofuel)asalternativetodisposal.

ACKNOWLEDGEMENTS

Theauthorwould liketoacknowledgeDr.AlisonPhairandProfessorAlanSimsonfortheirkindwordsofwisdom and encouragement. I would also like to thank Mark Warner, Louise Hartley, Lorraine Foster,Joanne Jolley,AdrianAppleyard,andRobinBrinkworth for theirhelp inmaking theprojectpossible.Theproject is funded inpartby theLeedsBeckettUniversityEnterpriseServices,UnLtdSocialEnterpriseandtheHigherEducationFundingCouncilforEngland(HEFCE).

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