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6/09/2015Solid Waste Management – Dr. B. Fei-

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3. COOPERATION PRINCIPLE3. COOPERATION PRINCIPLE

The The Cooperation Principle Cooperation Principle is based on the notion is based on the notion that conflicts can be resolved by the involvement that conflicts can be resolved by the involvement of all affected parties.of all affected parties.

AnAn attemptattempt isis mademade toto negotiatenegotiate forfor thetheadoptionadoption ofof certaincertain environmentalenvironmental qualityqualitygoals,goals, ee..gg..,, withwith thethe resultresult ofof voluntaryvoluntaryselfself--restrainsrestrains insteadinstead ofof governmentgovernmentmandatesmandates..

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-- AllAll political,political, socialsocial andand economiceconomic groupsgroups andandforcesforces shouldshould bebe involvedinvolved inin solutionsolution findingfinding(of(of environmentalenvironmental problems)problems)..

-- ThereThere isis participationparticipation ofof allall groupsgroups andand forcesforcesinin implementationimplementation ofof environmentalenvironmental solutionssolutions..

The Cooperation Principle ensures that:The Cooperation Principle ensures that:

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INCENTIVES FOR ENVIRONMENTALLY SOUND INCENTIVES FOR ENVIRONMENTALLY SOUND ACTIONACTION

OftenOften thethe truetrue economiceconomic costscosts ofof solidsolid wastewastemanagementmanagement areare hiddenhidden andand farfar removedremoved fromfromproducerproducer andand consumerconsumer decisionsdecisions..

ForFor example,example,somesome solidsolid wastewaste management’smanagement’s costscostsareare paidpaid outout ofof generalgeneral taxtax revenuesrevenuesandand areare notnot apparentapparent toto thethe taxtax payerpayer..

This does not produce any incentive to reduce This does not produce any incentive to reduce wastes!wastes!

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UncontrolledUncontrolled releasesreleases fromfrom solidsolid wastewastemanagementmanagement unitsunits cancan resultresult inin environmentalenvironmentaldamagesdamages withwith economiceconomic implicationsimplications..

AllAll ofof thesethese costscosts mustmust bebe fullyfully accountedaccounted forforandand paidpaid forfor byby thethe responsibleresponsible partiesparties..

EconomicEconomic andand environmentalenvironmental efficiencyefficiency dependsdepends uponupon

thethe polluterpolluter payingpaying forfor thethe costscosts ofof pollutionpollution andand notnot

subsidizingsubsidizing thesethese costscosts inin anan indirectindirect wayway throughthrough otherother

partiesparties..

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AA numbernumber ofof practicalpractical approachesapproaches whichwhich accountaccountforfor thesethese costscosts andand cancan incorporateincorporate themthem intointoproduction,production, consumptionconsumption andand wastewaste managementmanagementdecisionsdecisions..

IndividuationIndividuation ofof cost,cost, EcoEco--taxtax andand EcoEco--chargecharge areareexamplesexamples ofof somesome ofof thethe economiceconomic instrumentsinstrumentsappliedapplied inin ensuringensuring soundsound environmentenvironment..

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Example:Example:


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Economic instruments applied in ensuring Economic instruments applied in ensuring sound environmentsound environment

Eco-tax, Eco-chargeEco-tax, Eco-charge

Individuation of costIndividuation of cost

- Individual solid waste disposalcharge proportional to theamount of waste produced- Individual charge for waterconsumption and waste waterdischarge

- "Penalisation" of environmental/resource consumption by anadditional tax, charge, or fee

- Simultaneously, an alternativeprocess or product is supported bytax abatement or financial aid orsubsidies

e.g.

e.g.

money

Cost and price calculationCost and price calculation

e.g.

The price of a product includesthe cost for recycling and disposal

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PATHWAY OF WASTE FROM GENERATION TO PATHWAY OF WASTE FROM GENERATION TO FINAL DISPOSALFINAL DISPOSAL

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Summary of the functional elements of Summary of the functional elements of waste management systemwaste management system

Waste generationWaste generation

Waste handling,separation, storage,

processing at the source

Waste handling,separation, storage,

processing at the source

Waste collectionWaste collection

Transfer and transportTransfer and transport

Separation, processing,transformation of solidwaste (+marketing of

products)

Separation, processing,transformation of solidwaste (+marketing of

products)

DisposalDisposal

- material that is identified as no longer being of value,should be gathered together for disposal (not thrown away)- as activity, it is not very controllable (at present)

- Activities before waste is placed in containers for collection(separation at source, internal reuse and recovery, separatedcollection, proper on-site collection, transportation tocontainer sites)

- gathering solid waste from source sites (hauling),- transportation site where the vehicle is emptied (transferstation, landfill disposal site etc.)- waste collection often accounts> 50% of disposal costs!

- transfer of waste from smaller collection vehicle to largertransport equipment at transfer station- subsequent transport to the processing or disposal site

- waste materials from curbside collection, drop off, buy backcenters will be processed at special sites,- simultaneous materials recovery, detoxification, mass andvolume reduction, energy recovery,- mechanical, biological, chemical processes of very widevariety are included

- final functional element, is the ultimate fate of all solid waste,- a modern landfill is an engineering facility for disposalwithout nuisances of hazards to the public health andenvironment

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Stored over a period of time (e.g., week) by the Stored over a period of time (e.g., week) by the generators, generators,

Collected at a set frequency andCollected at a set frequency and

Transported to a proper facility for disposal/recyc lingTransported to a proper facility for disposal/recyc ling

TheThe solidsolid wastewaste andand recyclablesrecyclables areare usuallyusually

Storage and collection strategies for large communities with

high population densities are different from those suitable for

relatively small communities with low population densities.

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NBNB:: FundingFunding levelslevels forfor thethe programprogram willwill dictatedictate thethe levellevel ofofmechanizationmechanization andand frequencyfrequency..

�� solidsolid wastewaste volumevolume discardeddiscarded perper dayday�� accessibilityaccessibility toto thethe dumpster,dumpster,�� weather,weather, andand availabilityavailability ofof storagestorage spacespace

Collection frequency also depends onCollection frequency also depends on

QuesQues.. WhatWhat areare thethe possiblepossible frequenciesfrequencies ofof collectioncollection ofof

refuserefuse fromfrom itsits generationgeneration inin youryour community?community?

Which of them is most expensive but cost effective?Which of them is most expensive but cost effective?

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ForFor economicaleconomical wastewaste collectioncollection system,system, thethefollowingfollowing logisticallogistical questionsquestions areare importantimportant..

HOUSEHOLD WASTE COLLECTION HOUSEHOLD WASTE COLLECTION

Safe removalSafe removalAdherence to health standardsAdherence to health standardsMeeting public and private needs Meeting public and private needs Efficiency.Efficiency.

The overall objectives are: The overall objectives are:

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What type of containers, dumping devices, vehicles, and What type of containers, dumping devices, vehicles, and crew are to be selected?crew are to be selected?

How can the collection routes be integrated into a How can the collection routes be integrated into a disposal plan?disposal plan?

In what order does the collection proceed in the in dividual In what order does the collection proceed in the in dividual towns or subtowns or sub--divisions?divisions?

What kind of capacity is required for the above men tioned What kind of capacity is required for the above men tioned facilities? facilities?

Which locations for storage, transfer, disposal, an d Which locations for storage, transfer, disposal, an d material recovery facilities are to be selected?material recovery facilities are to be selected?

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FACTORS INFLUENCING ROUTE PLANNING AND FACTORS INFLUENCING ROUTE PLANNING AND WASTE COLLECTIONWASTE COLLECTION

�� ActualActual wastewaste quantityquantity inin thethe entireentire collectioncollection areaarea andand atat

anyany oneone loadingloading point,point,

�� PotentialPotential loadingloading pointspoints inin thethe collectioncollection area,area,

�� RegionalRegional developmentdevelopment patternspatterns inin thethe collectioncollection area,area,

�� TrafficTraffic patternspatterns ofof thethe wastewaste collectioncollection route,route,

�� TrafficTraffic patternspatterns andand distancesdistances ofof thethe transportationtransportation route,route,

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�� Container system(s) used,Container system(s) used,

��Container transportation system used, and Container transportation system used, and

�� Efficiency of collection vehicles used.Efficiency of collection vehicles used.

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TRANSFER STATIONTRANSFER STATION

WasteWaste transfertransfer stationsstations areare facilitiesfacilities wherewheremunicipalmunicipal solidsolid wastewaste isis unloadedunloaded fromfrom collectioncollectionvehiclesvehicles andand brieflybriefly heldheld whilewhile itit isis reloadedreloaded ontoontolargerlarger longlong--distancedistance transporttransport vehiclesvehicles forforshipmentshipment toto landfillslandfills oror otherother treatmenttreatment oror disposaldisposalfacilitiesfacilities..

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MSW collectionMSW collection

MSW transferMSW transfer

MSW transportationMSW transportation

Task: - transfer of waste from (small) collection vehicle to largertransportation vehicle,- cost reduction of MSW transportation if disposal site is farfrom pick-up site,- reduce the number of times of vehicular trips to and fromthe disposal site,- compaction of wastes, waste separation (optional).

Task: - transfer of waste from (small) collection vehicle to largertransportation vehicle,- cost reduction of MSW transportation if disposal site is farfrom pick-up site,- reduce the number of times of vehicular trips to and fromthe disposal site,- compaction of wastes, waste separation (optional).

TheThe PRIMARYPRIMARY REASONREASON forfor usingusing aa transfertransfer stationstation isis totoreducereduce thethe costcost ofof transportingtransporting wastewaste toto disposaldisposal facilitiesfacilities..

AdvantagesAdvantages

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SomeSome basicbasic TransferTransfer StationStation TechnologiesTechnologies

Open top transfer trailersOpen top transfer trailers

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Compactor systemCompactor system

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Precompactor system Precompactor system

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WASTE PROCESSING AND DISPOSAL WASTE PROCESSING AND DISPOSAL

MunicipalMunicipal solidsolid wastewaste maymay bebe treatedtreated ororprocessedprocessed priorprior toto finalfinal disposaldisposal..

SolidSolid wastewaste processingprocessing providesprovides severalseveraladvantagesadvantages::

ReductionReduction inin thethe totaltotal volumevolume andand weightweight ofof wastewastematerialmaterial thatthat requiresrequires finalfinal disposaldisposal..

VolumeVolume reductionreduction helpshelps toto conserveconserve landlandresourcesresources..

ItIt alsoalso reducesreduces thethe totaltotal costcost ofof transportingtransporting thethewastewaste toto itsits finalfinal disposaldisposal sitesite.. 20

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TheThe objectivesobjectives ofof processingprocessing wastewaste dependsdepends ononwhetherwhether;; thethe wastewaste isis

�� OrientedOriented toto meetmeet landfilllandfill requirementsrequirementsoror�� OrientedOriented toto enhanceenhance reusereuse andand recyclingrecycling

WasteWaste orientedoriented toto meetmeet landfilllandfill requirementsrequirementsshouldshould bebe;; inertinert,, immobilizedimmobilized oror stabilizedstabilized..

InertizationInertization ofof wastewaste isis thethe avoidanceavoidance ofof chemicalchemical reactionsreactions andand biodegradationsbiodegradations

byby adequateadequate prepre--treatmenttreatment ofof thethe wastewaste..

ImmobilizationImmobilization ofof wastewaste isis thethe reductionreduction ofof thethe solubilitysolubility andand leachabilityleachability ofof

substancessubstances byby adequateadequate pretreatmentpretreatment..

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ForFor wastewaste orientedoriented toto enhanceenhance reusereuse andandrecyclingrecycling;;

�� therethere shouldshould bebe separationseparation ofof valuablevaluableandand hazardoushazardous materialsmaterials

�� shouldshould bebe preparedprepared forfor recovery,recovery, reusereuseandand recyclingrecycling

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Oriented to meet landfillrequirements

Oriented to meet landfillrequirements

Objectives of processingwaste

Objectives of processingwaste

Oriented to enhancereuse and recycling

Oriented to enhancereuse and recycling

Separation ofvaluable andhazardousmaterials

Separation ofvaluable andhazardousmaterials

Preparation forrecovery, reuseand recycling

Preparation forrecovery, reuseand recycling

InertizationInertization

ImmobilizationImmobilization

StabilizatonStabilizaton

SummarySummary

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Waste processingoperations


Physico-chemicalconversion

Physico-chemicalconversionMechanical

operations

Mechanicaloperations Thermal

treatment

Thermaltreatment Biological

transformation

Biologicaltransformation

organic matter only hazardous waste mainly

e.g.- size reduction- sieving- separation- compacting- storage-transportation

e.g.-combustion- pyrolysis- gasifying

further:-drying-thermal decomposition

e.g.- digestion, fermentation- composition- rotting- worm compositing

e.g.- neutralization- detoxification- precipitation- a n y c h e m i c a lreaction- solidification

TheThe mostmost widelywidely usedused municipalmunicipal wastewaste treatmenttreatmentoperationsoperations..

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Composting

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Physico-chemicalconversion

Physico-chemicalconversionMechanical

operations

Mechanicaloperations Thermal

treatment

Thermaltreatment Biological

transformation

Biologicaltransformation

- b y t h e a c t i o n o fmechanica l fo rces orfields only- no conversion of thechemical character ofsubstances- o u t p u t i s s t r o n g l ydetermined by the inputand the operation- n o g e n e r a t i o n o fhazardous substances- l o w e n e r g yconsumption

- change in chemicalc o m p o s i t i o n a n dphysical properties ofwaste- d e s t r u c t i o n o f a l lorganic matter- recovery o f energyand of materials- best reduction of massand volume- h i g h d e g r e e o fdetoxification- generat ion of (s ideproducts)

- applicable to nativeorganic matter only- m o s t l y s i m p l edesign, lit t le or noenergy consumption- r e c o v e r y o fmaterials (biogas,compost)- poor reduction ofvolume and mass- fair inertization andimmobilization

- requires additionale n e r g y a n dchemicals- low throughout- b a t c h w i s eoperation mainly- expensive- often hazardousside products thatmust be removedadditionally- high requirementson labour safety,environmental andhealth protection

Characteristics of the various waste processing ope rationsCharacteristics of the various waste processing ope rations

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The Systems Of Waste Processing The Systems Of Waste Processing

Thermal processingThermal processingBiological

processing

Biologicalprocessing

Mechanicalprocessing

Mechanicalprocessing

Aerobiccomposting

Waste ProcessingWaste ProcessingRecovery of material

and energy

Immobilization andinertization of waste

to be disposed

Aerobicrotting

Anaerobicdigestion

Compost"Stable

recyclables"Biogas,compost

size reduction,classifying etc.

size reduction,classifying etc. Mechanical

separation

Mechanicalseparation

Remainingwaste tolandfill

Recyclables

IncinerationIncineration

PyrolysisPyrolysis Gasific

ation

Gasification

Energy

Syn gas

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PyrolysisPyrolysis isis thethe thermalthermal decompositiondecomposition ofof organicorganic wastewaste underunder

pressurepressure inin thethe absenceabsence ofof oxygenoxygen (and(and atat relativelyrelatively lowlow

temperatures,temperatures, betweenbetween 350350ooCC––500500ooC,)C,) toto produceproduce aa carbonaceouscarbonaceous

charchar (consisting(consisting ofof purepure carboncarbon andand inorganicinorganic materialmaterial suchsuch asas

ash),ash), pyrolyticpyrolytic oiloil andand combustiblecombustible gasesgases..

GasificationGasification differsdiffers fromfrom pyrolysispyrolysis inin thatthat oxygenoxygen inin thetheformform ofof air,air, steamsteam oror purepure oxygenoxygen isis reactedreacted atat highhightemperaturetemperature (between(between 800800 ooCC--900900ooC)C) withwith thethe availableavailablecarboncarbon inin thethe wastewaste toto produceproduce aa gasgas productproduct (low(low--calorificcalorific gasgas -- COCO 22,, H,H, CO,CO, CHCH44 andand otherother hydrocarbon)hydrocarbon)ashash andand aa charcoalcharcoal productproduct..

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�� TheThe potentialpotential forfor environmentalenvironmental cleanclean processprocess routesroutes

withwith lowlow emissionsemissions

�� TheThe creationscreations ofof gaseousgaseous oror liquidliquid fuelfuel facilitiesfacilities forfor

directdirect conversionconversion ofof thethe productproduct intointo electricityelectricity..

Principal benefits of pyrolysis and gasification includes:Principal benefits of pyrolysis and gasification includes:

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ItIt isis believedbelieved thatthat compostingcomposting beganbegan shortlyshortly afterafterhumanshumans startedstarted toto cultivatecultivate foodfood..

TheThe typetype ofof compostcompost waswas mostmost likelylikely animalanimalmanuremanure..

InIn fact,fact, naturenature hashas beenbeen engagedengaged inin compostingcompostingsincesince thethe veryvery beginningbeginning..

TheThe wonderfulwonderful smellsmell ofof aa forestforest floorfloor isis thethe smellsmellofof humushumus whichwhich is,is, quitequite simply,simply, completelycompletelyrottedrotted plantsplants andand animalsanimals..

HISTORY OF COMPOSTINGHISTORY OF COMPOSTING

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CompostingComposting isis defineddefined asas aa specializedspecialized partpart ofofrecyclingrecycling inin whichwhich organicorganic wasteswastes arearebiologicallybiologically decomposeddecomposed underunder controlledcontrolledboundariesboundaries thatthat convertconvert themthem intointo aa productproduct thatthatcancan bebe appliedapplied toto thethe landland beneficiallybeneficially withoutwithoutenvironmentalenvironmental harmharm..

CompostingComposting isis defineddefined asas aerobicaerobic ratherrather thanthananaerobicanaerobic degradationdegradation ofof biodegradablebiodegradable organicorganicwastewaste suchsuch asas foodfood andand gardengarden wastewaste..

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SOME DEFINITIONS OF COMPOSTINGSOME DEFINITIONS OF COMPOSTING

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CompostingComposting MSWMSW doesdoes notnot eliminateeliminate thethe needneedforfor landfilllandfill..

StudiesStudies showsshows that,that, onlyonly 3030%% toto 4040%% ofofincomingincoming MSWMSW willwill havehave toto bebe landfilledlandfilled afteraftercompostingcomposting

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thisthis amountamount couldcould bebe reducedreduced stillstillfurtherfurther inin communitiescommunities withwith activeactiverecyclingrecycling programsprograms..


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CompostingComposting isis thethe controlledcontrolled biologicalbiologicaldecompositiondecomposition andand conversionconversion ofof solidsolid organicorganicmaterialmaterial intointo aa humushumus likelike substancesubstance calledcalledcompostcompost..

CompostCompost isis aa combinationcombination ofof decomposeddecomposed plantplantandand animalanimal materialsmaterials andand otherother organicorganic materialsmaterialsthatthat areare beingbeing decomposeddecomposed largelylargely throughthroughaerobicaerobic decompositiondecomposition intointo aa richrich blackblack soilsoil..

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PRINCIPLESPRINCIPLES OFOF COMPOSTINGCOMPOSTING

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CompostingComposting isis aa managedmanaged systemsystem thatthat usesusesmicrobialmicrobial activityactivity ((PsychrophilesPsychrophiles ,, MesophilesMesophiles ,, andandThermophilesThermophiles ))

microorganismsmicroorganisms breakbreak downdown complexcomplex organicorganicmoleculesmolecules (i(i..ee.. proteins,proteins, aminoamino acids,acids,carbohydrates,carbohydrates, etcetc..)) intointo simplersimpler onesones likelikecellulosecellulose..

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THE COMPOSTING PROCESSTHE COMPOSTING PROCESS

toto degradedegrade rawraw organicorganic materials,materials, soso thatthat thetheendend--productproduct isis relativelyrelatively stable,stable, reducedreduced ininquantityquantity (when(when comparedcompared toto thethe initialinitialamountamount ofof waste),waste), andand freefree fromfrom offensiveoffensiveodorsodors..


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INITIAL STAGE COMPOSTINGINITIAL STAGE COMPOSTING

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ThereThere areare certaincertain environmentalenvironmental factorsfactors thatthataffectaffect thethe raterate andand speedspeed ofof compostingcomposting..

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FACTORS AFFECTING COMPOSTINGFACTORS AFFECTING COMPOSTING

TheThe organismsorganisms thatthat makemake thethe compostcompost needneed

WhenWhen providedprovided withwith aa favorablefavorable balance,balance, theythey willwillproduceproduce compostcompost quicklyquickly..

FOOD (carbon and nitrogen), AIR, and MOISTURE.FOOD (carbon and nitrogen), AIR, and MOISTURE.


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OtherOther factorsfactors affectingaffecting thethe speedspeed ofof compostingcompostingincludeinclude;;

surfacesurface size/particlesize/particle size,size, temperature,temperature, volume,volume,andand pHpH..

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DecomposerDecomposer organismsorganisms needneed waterwater toto livelive..

MicrobialMicrobial activityactivity occursoccurs mostmost rapidlyrapidly inin thinthin waterwaterfilmsfilms onon thethe surfacesurface ofof organicorganic materialsmaterials..

MicroorganismsMicroorganisms cancan onlyonly utilizeutilize organicorganicmoleculesmolecules thatthat areare dissolveddissolved inin waterwater..

TheThe optimumoptimum moisturemoisture contentcontent forfor aa compostcompost pilepileshouldshould rangerange fromfrom 4040 toto 6060 percentpercent..

IfIf therethere isis lessless thanthan 4040 percentpercent moisture,moisture, bacteriabacteriaslowslow downdown andand maymay becomebecome dormantdormant..

MOISTURE CONTENT


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IfIf therethere isis moremore thanthan 6060 percent,percent, waterwater willwill forceforceairair outout ofof pilepile porepore spaces,spaces, suffocatingsuffocating thethe aerobicaerobicbacteriabacteria..

Additionally,Additionally, itit createscreates conditionsconditions thatthat favourfavour odorodorproductionproduction inin thethe pilepile andand restrictrestrict itsits temperaturetemperatureriserise..

AsAs aa rulerule ofof thumb,thumb, ifif thethe compostcompost mixturemixture feelsfeelsmoistmoist withoutwithout waterwater drippingdripping fromfrom aa handfulhandful whenwhensqueezed,squeezed, thethe moisturemoisture isis adequateadequate..

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ProperProper aerationaeration isis aa keykey environmentalenvironmental factorfactor..

ManyMany microorganisms,microorganisms, includingincluding aerobicaerobic bacteria,bacteria,needneed oxygenoxygen..

TheyThey needneed oxygenoxygen toto produceproduce energy,energy, growgrowquickly,quickly, andand consumeconsume moremore materialsmaterials..

AERATIONAERATION ANDAND OXYGENOXYGEN SUPPLYSUPPLY


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OxygenOxygen consumptionconsumption inin aa compostingcomposting massmassdependsdepends onon severalseveral factorsfactors suchsuch asas;;

MoistureMoisture content,content,Temperature,Temperature,ParticleParticle sizesize ofof thethe massmass oror porosityporosity (spaces(spacesbetweenbetween particlesparticles inin thethe compostcompost pile),pile),TheThe stagestage ofof thethe process,process, windwind etcetc..

WhereWhere thethe supplysupply ofof oxygenoxygen isis insufficient,insufficient, thethe growthgrowth ofofaerobicaerobic micromicro--organismsorganisms responsibleresponsible forfor decompositiondecomposition isislimitedlimited hencehence hinderinghindering decompositiondecomposition..

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TEMPERATURETEMPERATURE

TemperatureTemperature isis anotheranother importantimportant factorfactor inin thethecompostingcomposting processprocess andand isis relatedrelated toto properproper airairandand moisturemoisture levelslevels..

AsAs thethe microorganismsmicroorganisms workwork toto decomposedecompose thethecompost,compost, theythey givegive offoff heatheat whichwhich inin turnturnincreasesincreases pilepile temperaturestemperatures..


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TemperatureTemperature isis directlydirectly proportionalproportional toto thethebiologicalbiological activityactivity withinwithin thethe compostingcomposting systemsystem..

AsAs thethe metabolicmetabolic raterate ofof thethe microbesmicrobes acceleratesacceleratesthethe temperaturetemperature withinwithin thethe systemsystem increasesincreases..

Conversely,Conversely, asas thethe metabolicmetabolic raterate ofof thethe microbesmicrobesdecreases,decreases, thethe systemsystem temperaturetemperature decreasesdecreases..

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>> 5555 °°CC toto maximizemaximize sanitation,sanitation,

4545--5555 °°CC toto maximizemaximize thethe biodegradationbiodegradation rate,rate,

3535--4040 °°CC toto maximizemaximize microbialmicrobial diversitydiversity..

InIn biologicalbiological termsterms thethe operatingoperating temperaturetemperaturerangesranges areare asas followsfollows::


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VOLUMEVOLUME

SmallerSmaller compostcompost pilespiles willwill stillstill decomposedecompose material,material, butbuttheythey maymay notnot heatheat upup well,well, andand decompositiondecomposition isis likelylikely tototaketake longerlonger..

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VolumeVolume isis aa factorfactor inin retainingretaining compostcompost pilepile heatheat..

InIn orderorder toto becomebecome selfself insulatinginsulating andand retainretainheat,heat, pilespiles maymay bebe mademade toto aa oneone cubiccubic sizesize..

OOnene cubiccubic yardyard sizesize retainsretains heatheat andand moisture,moisture,butbut isis notnot tootoo largelarge thatthat thethe materialmaterial willwill becomebecomeunwieldyunwieldy forfor turningturning..

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PARTICLE SIZE PARTICLE SIZE

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ParticleParticle sizesize affectsaffects thethe raterate ofof organicorganic mattermatterbreakdownbreakdown..

TheThe moremore “surface“surface area”area” available,available, thethe easiereasier ititisis forfor microorganismsmicroorganisms toto work,work, becausebecause activityactivityoccursoccurs atat thethe interfaceinterface ofof particleparticle surfacessurfaces andandairair..

MicroorganismsMicroorganisms areare ableable toto digestdigest more,more,generategenerate moremore heat,heat, andand multiplymultiply fasterfaster withwithsmallersmaller piecespieces ofof materialmaterial..


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In a composting process, In a composting process,

AerationAeration andand degradabilitydegradability cancan bebe improvedimproved bybyreducingreducing thethe particleparticle sizesize whilewhile increasingincreasing thethesurfacesurface area,area, asas longlong asas porosityporosity remainsremainsaboveabove 3030%%..

OptimumOptimum particleparticle sizesize ofof compostingcomposting materialmaterialforfor properproper aerationaeration ofof aa compostcompost pilepile rangesrangesfromfrom 33..11 toto 1212..77 mmmm..

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TheThe compostingcomposting processprocess isis relativelyrelativelyinsensitiveinsensitive toto pHpH withinwithin thethe rangerange commonlycommonlyfoundfound inin mixturesmixtures ofof organicorganic materials,materials, largelylargelybecausebecause ofof thethe broadbroad spectrumspectrum ofofmicroorganismsmicroorganisms involvedinvolved..

EachEach ofof thethe microbesmicrobes responsibleresponsible inin thethebiologicalbiological transformationtransformation ofof thethe compostcompost pilepilehashas theirtheir ownown optimumoptimum pHpH rangesranges..

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pHpH


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pHpH willwill fallfall initiallyinitially asas thethe processprocess beginsbegins..

AsAs thethe biologicalbiological decompositiondecomposition processprocesscontinues,continues, thethe pHpH willwill increaseincrease toto nearnear neutralneutrallevelslevels..

AcidityAcidity ofof compostcompost mostmost oftenoften dependsdepends onon thetheamountamount ofof moisturemoisture availableavailable andand thethe degreedegree ofofaerationaeration..

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Organic material provides food for organisms in Organic material provides food for organisms in the form of carbon and nitrogen.the form of carbon and nitrogen.

Carbon and nitrogen levels vary with each organic Carbon and nitrogen levels vary with each organic material. material.

CarbonCarbon--rich materials tend to be dry and brown rich materials tend to be dry and brown such as leaves, straw, and wood chips.such as leaves, straw, and wood chips.

Nitrogen materials tend to be wet and green such Nitrogen materials tend to be wet and green such as fresh grass clippings and food waste.as fresh grass clippings and food waste.

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C/N RATIOC/N RATIO


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WhenWhen therethere isis tootoo muchmuch nitrogen,nitrogen, pilespiles willwill likelylikelyreleaserelease thethe excessexcess asas smellysmelly ammoniaammonia gasgas..

TooToo muchmuch nitrogennitrogen cancan alsoalso causecause aa riserise inin thethepHpH levellevel whichwhich isis toxictoxic toto somesome microorganismsmicroorganisms..

AcceptableAcceptable C/NC/N ratioratio generallygenerally rangesranges fromfrom 2525::11toto 4040::11,, andand maymay eveneven reachreach asas highhigh asas 5050::11..

ReductionReduction ofof thethe C/NC/N ratioratio duringduring thethe compostingcompostingprocessprocess isis aa goodgood indicationindication ofof digestiondigestion ofofcarboncarbon sourcessources byby microorganismsmicroorganisms andandproductionproduction ofof COCO 22 andand heatheat..

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Material Nitrogen (% dry weight) C/N ratioUrine 15-18 0.8 Mixed slaughterhouse waste 7-10 2Night soil 5.5 – 6.5 6 – 10Digested sewage sludge 1.9 16Activated sludge 5.0 – 6.0 6Young grass clippings 4.0 12Cabbage 3.6 12Weeds 2.0 19Grass clippings (average mixed) 2.4 19Farmyard manure (average) 2.15 14Seaweed 1.9 19Potato haulms 1.5 25Oat straw 1.05 48Fresh sawdust 0.11 511Food waste 2.0 – 3.0 15Fruit waste 1.5 35Refuse 0.5 – 1.4 30 – 80Wood 0.07 700

Approximate Nitrogen content and C/N Ratios for som e Approximate Nitrogen content and C/N Ratios for som e Compostable MaterialsCompostable Materials

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ThisThis hashas beenbeen attributedattributed toto thethe releaserelease ofof sulfursulfurcompoundscompounds suchsuch asas hydrogenhydrogen sulfide,sulfide, methylmethylmercaptanmercaptan andand methylmethyl sulfidesulfide inin thethe earlyearly stagesstages ofofcompostingcomposting..

AAlsolso inadequateinadequate stabilizationstabilization ofof thethe compostcompost whichwhichmightmight bebe duedue toto tootoo highhigh moisturemoisture contentcontent ofof thethematerialmaterial usedused forfor compostingcomposting..

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ODOUR

OneOne ofof thethe majormajor complaintscomplaints facedfaced duringduringcompostingcomposting isis thethe smellsmell thatthat isis generatedgenerated

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CompostCompost QualityQuality reflectsreflects thethe chemicalchemical makeupmakeup ofofaa givengiven compostcompost..

AA compostcompost cancan bebe maturemature (i(i..ee..,, fullyfully composted)composted)butbut cancan bebe ofof poorpoor qualityquality duedue toto lowlow nutrientnutrientlevelslevels..

TheThe nutrientnutrient valuevalue ofof compostscomposts variesvaries widely,widely,dependingdepending uponupon thethe naturenature ofof feedstockfeedstockcompostedcomposted..

COMPOST QUALITY


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Substance Percentage by weight

Organic matter 25 – 50

Carbon 8 – 50

Nitrogen (as N) 0.4 – 3.5

Phosphorous (as P2O5) 0.3 – 3.5

Potassium (as K2O) 0.5 – 1.8

Ash 20 – 65

Calcium (as CaO) 1.5 – 7

Composition of mineral elements in finished compost

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IfIf initialinitial materialmaterial containscontains grassgrass clippings,clippings, weeds,weeds,oror manure,manure, itit willwill bebe richerricher inin nitrogennitrogen andand otherothernutrientsnutrients thanthan ifif itit containscontains mainlymainly straw,straw, litter,litter, dirtdirtoror corncorn stalksstalks..

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BENEFICIAL USES OF COMPOST MATERIAL BENEFICIAL USES OF COMPOST MATERIAL

�� CompostCompost enrichedenriched soilsoil cancan helphelp suppresssuppress

diseasesdiseases andand wardward offoff pestspests..

�� ItIt destroysdestroys diseasedisease organismsorganisms andand createscreates aa

nutrientnutrient--richrich productproduct thatthat cancan bebe usedused oror soldsold..

�� TheseThese beneficialbeneficial usesuses ofof compostcompost savesave revenuerevenue..

�� ReduceReduce thethe useuse ofof pesticides,pesticides, andand helphelp conserveconserve

naturalnatural resourcesresources..

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DISEASEDISEASE CONTROLCONTROL FORFOR PLANTSPLANTS ANDAND ANIMALSANIMALS


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AA newnew compostcompost technology,technology, knownknown asas compostcompostbioremediation,bioremediation, isis currentlycurrently beingbeing usedused toto restorerestorecontaminatedcontaminated soils,soils, controlcontrol odors,odors, andand degradedegradevolatilevolatile organicorganic compoundscompounds..

ItIt hashas alsoalso beenbeen shownshown toto bindbind heavyheavy metalsmetals andandpreventprevent themthem fromfrom migratingmigrating toto waterwater resourcesresources ororbeingbeing absorbedabsorbed byby plantsplants..

SOIL REMEDIATION

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NativeNative plantsplants inhabitinginhabiting ourour countrycountry sidessidesprovideprovide foodfood forfor nearlynearly everyevery otherother membermember ofof thethehabitathabitat..

AsAs plantsplants die,die, theythey continuecontinue toto supportsupport grasses,grasses,flowers,flowers, andand treestrees byby becomingbecoming thethe humushumus..

OriginalOriginal wetlandwetland plantsplants cancan bebe restoredrestored withwith thetheuseuse ofof compostcompost duringduring plantingplanting..

CompostCompost providesprovides treetree seedlingsseedlings withwith addedaddedrigorrigor forfor survivalsurvival andand growthgrowth..

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WETLANDS RESTORATION AND HABITAT WETLANDS RESTORATION AND HABITAT REVITALIZATION REVITALIZATION


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CompostCompost hashas thethe abilityability toto helphelp regenerateregenerate poorpoorsoilssoils..TheThe compostingcomposting processprocess encouragesencourages thetheproductionproduction ofof beneficialbeneficial micromicro--organismsorganisms (mainly(mainlybacteriabacteria andand fungi)fungi) whichwhich inin turnturn breakbreak downdownorganicorganic mattermatter toto createcreate humushumus..

SOIL ENRICHMENT

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GENERAL LAYOUT OF AEROBIC ROTTING PROCESSESGENERAL LAYOUT OF AEROBIC ROTTING PROCESSES

Microorganism:- bacteria - actinomycetes- fungi - yeast- algae - protozoonsOthers: - worms

Microorganism:- bacteria - actinomycetes- fungi - yeast- algae - protozoonsOthers: - worms

Organic substances +O2 CO2 + H2O +(N+S+P) + energy (thermal + biochemical)Organic substances +O2 CO2 + H2O +(N+S+P) + energy (thermal + biochemical)

O p t i m u m c o n d i t i o n s o f a e r o b i cbiodegradation (rotting process):- C/N - ratio 35 ... 50- pH - value 5......9- temperature 15.....55 oC- moisture content 45....55 %porosity (O2 -access) 25...35 %

O p t i m u m c o n d i t i o n s o f a e r o b i cbiodegradation (rotting process):- C/N - ratio 35 ... 50- pH - value 5......9- temperature 15.....55 oC- moisture content 45....55 %porosity (O2 -access) 25...35 %microorganism are ubiquituosly existent, only

optimum living conditions must be provided.

Phase I : Temperature rises up to 50 oC andabove quickly, mainly mesophilic microorganism,f o l l o w e d b y g r o w t h o f t h e r m o p h i l i cm i c r o o r g a n i s m . C o n v e r s i o n o f e a s i l ybiodegradable substances.Phase II : Temperature up to more than 75 oC,destruct ion of pathogens, weeds (disinfection,hygienization), killing of seeds

Phase III: Self-inhibition of microorganism, coolingdown, biodegradable substances. Degassing of plant-harming constituents (Ammonia, H2S, etc.)24 hrs 2 - 4 weeks up to 4 month

Tem

pera

ture

in o C

20

30

40

50

60Phase III

completion

Phase II: maindegradation

Phase IStarting

Time

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TYPES OF COMPOSTING TECHNOLOGIESTYPES OF COMPOSTING TECHNOLOGIES

InIn thisthis techniquetechnique thethe wastewaste isis piledpiled inin longlong rowsrows andand

turnedturned onceonce oror twicetwice perper week,week, ifif notnot dailydaily..

TheThe turningturning aeratesaerates thethe mixturemixture andand releasesreleases excessexcess

heatheat.. TurningTurning alsoalso increasesincreases thethe releaserelease ofof volatilesvolatiles..

WindrowsWindrows

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Initial stage of compostingInitial stage of composting


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Sewage sludge/SawdustSewage sludge/Sawdust

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ThisThis isis similarsimilar toto windrowingwindrowing exceptexcept thatthat thethepilespiles areare notnot turnedturned..

Rather,Rather, byby buildingbuilding thethe pilespiles onon toptop ofof aa gridgrid ofofperforatedperforated pipes,pipes, airair isis mechanicallymechanically drawndrawn ororforcedforced throughthrough thethe pipespipes usingusing vacuumvacuum ororforcedforced airair systemsystem..

Static piles Static piles


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Static piles with passive aeration tubesStatic piles with passive aeration tubes

ThisThis blowerblower forcesforces airair intointo aa staticstaticcompostcompost pilepile..

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ByBy compostingcomposting withinwithin anan enclosedenclosed reactor,reactor, thethe operationoperationcancan bebe optimizedoptimized toto completecomplete thethe processprocess inin asas littlelittle asasthreethree daysdays comparedcompared withwith asas muchmuch asas 3030 daysdays forforwindrowswindrows..

Enclosed reactor system Enclosed reactor system

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Composting chamber in operationFacility exterior, showing manifold


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ANAEROBICANAEROBIC DIGESTIONDIGESTION

HowHow anaerobicanaerobic digestiondigestion worksworks

TheThe materialmaterial toto bebe processedprocessed forfor thethe AnaerobicAnaerobicDigestionDigestion (AD)(AD) cancan bebe shreddedshredded toto increaseincrease thethesurfacesurface areaarea availableavailable toto microbesmicrobes inin thethe digestersdigestersandand hencehence increaseincrease thethe speedspeed ofof digestiondigestion..

TheThe ADAD processprocess takestakes placeplace inin anan airtightairtightcontainer,container, knownknown asas aa digesterdigester..

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TheThe firstfirst stagestage ofof ADAD isis aa chemicalchemical reactionreaction calledcalledhydrolysishydrolysis,, wherewhere complexcomplex organicorganic moleculesmolecules areare brokenbrokendowndown intointo simplesimple sugars,sugars, aminoamino acids,acids, andand fattyfatty acidsacids withwiththethe additionaddition ofof hydroxylhydroxyl groupsgroups..

AcidogenesisAcidogenesis -- furtherfurther brokenbroken downdown byby acidogenicacidogenic bacteriabacteria intointosimplersimpler molecules,molecules, VolatileVolatile FattyFatty AcidsAcids (VFAs)(VFAs) occurs,occurs, producingproducingammonia,ammonia, COCO 22 andand hydrogenhydrogen sulphidesulphide asas byproductsbyproducts..

AcetogenesisAcetogenesis -- thethe simplesimple moleculesmolecules fromfrom acidogenesisacidogenesis areare furtherfurtherdigesteddigested byby bacteriabacteria calledcalled acetogensacetogens toto produceproduce COCO 22,, hydrogenhydrogenandand mainlymainly aceticacetic acidacid..

MethanogenesisMethanogenesis -- methane,methane, COCO 22 andand waterwater areare producedproduced byby bacteriabacteriacalledcalled methanogensmethanogens..

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TheThe pHpH levellevel shouldshould bebe keptkept betweenbetween 55..55--88..55 andandthethe temperaturetemperature betweenbetween 3030--6060°°C,C, inin orderorder totomaximisemaximise digestiondigestion ratesrates..

Biomassproteins,

carbohydrates,fat

amino acids,sugars,glycerol

fatty acids

H2, CO2,acetic acid

organicacids,

alcohol,etc

H2, CO2,acetic acid

Biogas45-70%methane30 - 55 %

CO2

NH4, HPO4, H2S

Methanicbiodegradation

Hydrolysis acidic biodegradation

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A 500mA 500m33 anaerobic digester for treating anaerobic digester for treating

wastewater from a 10,000wastewater from a 10,000--pig farm in pig farm in

HangzhouHangzhou

ANAEROBIC DIGESTERS ANAEROBIC DIGESTERS


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Anaerobic bioreactor controlled landfill Anaerobic bioreactor controlled landfill technology technology

TheThe LandfillLandfill bioreactorbioreactor technologytechnology involvesinvolves

thethe controlledcontrolled additionaddition ofof moisture,moisture, increasedincreasedtemperaturestemperatures andand recirculationrecirculation ofof leachate,leachate, totoresultresult inin aa greatlygreatly acceleratedaccelerated raterate ofof wastewastedecompositiondecomposition andand landfilllandfill gasgas productionproduction..

Landfill-

Biological Reactor

MSW

water

Leachate

Gas

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