BiogasPlants
SeriesEditor:
ChristianV.Stevens, FacultyofBioscienceEngineering,GhentUniversity,Belgium
TitlesintheSeries:
WoodModification:Chemical,ThermalandOtherProcesses
CallumA.S.Hill
Renewables-BasedTechnology:SustainabilityAssessment
JoDewulf,HermanVanLangenhove Biofuels
WimSoetaert,ErikVandamme
HandbookofNaturalColorants
ThomasBechtold,RitaMussak
SurfactantsfromRenewableResources
MikaelKjellin,IngegärdJohansson
IndustrialApplicationsofNaturalFibres:Structure,PropertiesandTechnicalApplications JörgMüssig
ThermochemicalProcessingofBiomass:ConversionintoFuels,ChemicalsandPower
RobertC.Brown
BiorefineryCo-Products:Phytochemicals,PrimaryMetabolitesandValue-AddedBiomassProcessing ChantalBergeron,DanielleJulieCarrier,ShriRamaswamy AqueousPretreatmentofPlantBiomassforBiologicalandChemicalConversiontoFuelsandChemicals
CharlesE.Wyman
Bio-BasedPlastics:MaterialsandApplications
StephanKabasci
IntroductiontoWoodandNaturalFiberComposites
DouglasD.Stokke,QinglinWu,GuangpingHan CellulosicEnergyCroppingSystems
DouglasL.Karlen
IntroductiontoChemicalsfromBiomass,2ndEdition
JamesH.Clark,FabienDeswarte
LigninandLignansasRenewableRawMaterials:Chemistry,TechnologyandApplications FranciscoG.Calvo-Flores,JoseA.Dobado,JoaquínIsac-García,FranciscoJ.Martín-Martínez
SustainabilityAssessmentofRenewables-BasedProducts:MethodsandCaseStudies
JoDewulf,StevenDeMeester,RodrigoA.F.Alvarenga
CelluloseNanocrystals:Properties,ProductionandApplications WadoodHamad
Fuels,ChemicalsandMaterialsfromtheOceansandAquaticSources FrancescaM.Kerton,NingYan
Bio-BasedSolvents
FrançoisJérômeandRafaelLuque
NanoporousCatalystsforBiomassConversion Feng-ShouXiaoandLiangWang
ThermochemicalProcessingofBiomass:ConversionintoFuels,ChemicalsandPower,2ndEdition RobertBrown
ChitinandChitosan:PropertiesandApplications LambertusA.M.vandenBroekandCarmenG.Boeriu
TheChemicalBiologyofPlantBiostimulants DannyGeelen,LinXu BiorefineryofInorganics:RecoveringMineralNutrientsfromBiomassandOrganicWaste ErikMeers,EviMichels,RenéRietra,GerardVelthof ProcessSystemsEngineeringforBiofuelsDevelopment AdriánBonilla-Petriciolet,GadeP.Rangaiah WasteValorisation:WasteStreamsinaCircularEconomy CarolSzeKiLin,ChongLi,GuneetKaur,XiaofengYang High-PerformanceMaterialsfromBio-basedFeedstocks AndrewJ.Hunt,NontipaSupanchaiyamat,KaewtaJetsrisuparb,JesperT.Knijnenburg HandbookofNaturalColorants,2ndEdition ThomasBechtold,AvinashP.ManianandTungPham BiogasPlants:WasteManagement,EnergyProductionandCarbonFootprintReduction WojciechCzekała
Editedby
WOJCIECHCZEKAŁA
Pozna ´ nUniversityofLifeSciences,Poland
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Names:Czekała,Wojciech,editor.|Stevens,ChristianV.,editor.
Title:Biogasplants:wastemanagement,energyproductionandcarbon footprintreduction/editedbyWojciechCzekała,ChristianVStevens.
Description:Hoboken,NJ:Wiley,2024.|Series:Wileyseriesinrenewable resources|Includesindex.
Identifiers:LCCN2023046450(print)|LCCN2023046451(ebook)|ISBN 9781119863786(hardback)|ISBN9781119863779(adobepdf)|ISBN 9781119863922(epub)|ISBN9781119863946(oBook)
Subjects:LCSH:Biogas.|Renewableenergysources.
Classification:LCCTP359.B48B5372024(print)|LCCTP359.B48(ebook)| DDC665.7/76–dc23/eng/20231107
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ListofContributorsxvii
SeriesPrefacexxi
1AnaerobicDigestionProcessandBiogasProduction1 LiangliangWei,WeixinZhao,LikuiFeng,JianjuLi,XinhuiXia,HangYu, andYuLiu
1.1Introduction1
1.2BasicKnowledgesofADProcessesandOperations2
1.2.1FundamentalMechanismsandTypicalProcessesofAD2
1.2.2FactorsAffectingtheADProcessofBiogasProduction4
1.2.2.1Temperature4
1.2.2.2pH5
1.2.2.3OrganicLoadingRate(OLR)5
1.2.2.4Carbon–NitrogenRatio5
1.2.2.5Inoculum-to-SubstrateRatio(ISR)6
1.2.2.6SolidsConcentration6
1.2.2.7HydraulicRetentionTime(HRT)6
1.3CurrentChallengesofADProcessandBiogasProduction7
1.3.1AmmoniaInhibition7
1.3.2VolatileFattyAcidInhibition10
1.3.3PsychrophilicTemperatureInhibition12
1.4ProposedStrategiesforEnhancedBiogasProduction14
1.4.1PromotingDirectInterspeciesElectronTransfervia ConductiveMaterialsAdditive14
1.4.2Co-digestionofDifferentSubstrates16
1.4.3Bioaugmentation19
1.4.4BioelectrochemicalSystem-AssistedAD20
1.5Techno-EconomicandEnvironmentalAssessmentofAnaerobic DigestionforBiogasProduction22
1.5.1Techno-EconomicAnalysis22
1.5.2EnvironmentalFeasibilityandBenefitAssessment24 References26
2PretreatmentofLignocellulosicMaterialstoEnhanceBiogasRecovery37 JonathanT.E.Lee,NalokDutta,To-HungTsui,EeY.Lim,YanjunDai,and YenW.Tong
2.1Introduction37
2.1.1LignocellulosicWasteMaterialProduction38
2.1.2StructuralInsightofLignocellulosicMaterials39
2.1.3BiogasProductionfromLignocellulosicMaterialsandthe NeedforPretreatment40
2.2AvailablePretreatmentTechnologiesforLignocellulosicMaterials andtheCorrespondingBiogasRecoveryAssociated41
2.2.1PhysicalPretreatment41
2.2.1.1Comminution43
2.2.1.2MicrowaveThermalPretreatment43
2.2.1.3Extrusion44
2.2.1.4Ultrasonication45
2.2.2ChemicalPretreatment45
2.2.2.1AcidHydrolysisPretreatment45
2.2.2.2AlkaliHydrolysisPretreatment47
2.2.2.3IonicLiquidsPretreatment48
2.2.2.4DeepEutecticSolventsPretreatment48
2.2.2.5OrganosolventsPretreatment49
2.2.3BiologicalPretreatment49
2.2.3.1EnzymaticPretreatment50
2.2.3.2Whole-cellMicrobialPretreatment51
2.2.3.3FungalPretreatment52
2.2.3.4Ensiling52
2.2.3.5SummaryofIndividualPretreatmentEfficiencies53
2.2.4PhysiochemicalPretreatmentofLignocellulosicBiomassin theProductionofBiogas54
2.2.4.1HybridStateofArtLignocellulosicPretreatments54
2.3PertinentPerspectives58
2.3.1IntegratedBiorefineryWhileTreatingVariousWastes58
2.3.1.1MunicipalSolidWaste(MSW)58
2.3.1.2ForestryWaste59
2.3.1.3CropStraw59
2.3.2BiogasProductionfromLignocellulosicWasteandIts EconomicViability59
2.4Conclusions60 Acknowledgments61 References61
3BiogasTechnologyandtheApplicationforAgriculturalandFoodWaste Treatment73
WeiQiao,SimonM.Wandera,MengmengJiang,YapengSong,and RenjieDong
3.1DevelopmentofBiogasPlants73
3.1.1AgriculturalWaste74
3.1.1.1LivestockandPoultryManure74
3.1.1.2CropStraw74
3.1.2MunicipalSolidWaste75
3.1.2.1MunicipalSolidWaste75
3.1.2.2SewageSludge75
3.2AnaerobicDigestionProcess76
3.3BiogasProductionfromLivestockandPoultryManure77
3.3.1SuccessfulADofCattleandSwineManure77
3.3.1.1Industrial-scaleADofCattleManure77
3.3.1.2Industrial-scaleADofSwineManure77
3.3.2SuccessfulAnaerobicDigestionofChickenManureina LargePlant77
3.3.3StrategiesforMitigatingAmmoniaInhibitioninChicken ManureAD78
3.3.3.1SupplementationwithTraceElements78
3.3.3.2In-situAmmoniaStrippingforChickenManure Digesters79
3.4FoodWasteAnaerobicDigestion79
3.4.1ChallengesofFoodWasteADandtheSolutions79
3.4.1.1VFAsAccumulationinThermophilicADofFood Waste79
3.4.1.2ADTechnologiesforFoodWaste80
3.4.1.3AnaerobicMembraneBioreactorTechnologyfor FoodWaste81 References81
4BiogasProductionfromHigh-solidAnaerobicDigestionofFoodWaste andItsCo-digestionwithOtherOrganicWastes85 LeZhang,To-HungTsui,Kai-CheeLoh,YanjunDai,JingxinZhang,and YenWahTong
4.1Introduction85
4.2ReactorSystemsforHSAD86
4.2.1High-solidAnaerobicMembraneBioreactor86
4.2.2Two-stageHSADReactorSystem87
4.2.3High-solidPlug-flowBioreactor88
4.3IntensificationStrategiesforHSAD89
4.3.1High-solidAnaerobicCo-digestion(HS-AcD)89
4.3.2SupplementationofAdditives90
4.3.3BioaugmentationStrategiesforHSAD91
4.3.4OptimizationofProcessParameters91
4.4MicrobialCommunitiesforHSAD93
4.5DigestateManagementforHSAD94
4.6ConclusionsandPerspectives94 Acknowledgments95 References95
5Biomethane–ProductionandManagement101 WojciechCzekała,AleksandraŁukomska,andMartynaKuli ´ nska
5.1Introduction101
5.2PurificationandUsageofBiogas103
5.2.1BiologicalDesulfurizationWithintheDigester104
5.2.2DesulfurizationbyAdsorptiononIronHydroxide104
5.2.3DesulfurizationbyAdsorptiononActivatedCarbon104
5.3OpportunitiesforBiogasUpgrading105
5.3.1CO2 SeparationThroughMembranes105
5.3.2CO2 SeparationbyWaterScrubbing106
5.3.3ChemicalSeparationofCO2 /ChemicalScrubbing108
5.3.4PressureSeparationofCO2 (PressureSwingAdsorption)109
5.3.5CryogenicCO2 Separation109
5.4PossibilitiesofUsingBiomethane110
5.4.1ProductionofbioCNGandbioLNGFuels111
5.4.2ProductionofBiohydrogen111
5.5ProfitabilityofBiomethaneProductionandRecommendedSupport Systems112
5.6Conclusion113 References114
6TheBiogasUse117 MuhammadU.Khan,AbidSarwar,NalokDutta,andMuhammadArslan
6.1Introduction117
6.2BiogasUtilizationTechnologies118
6.3UseofBiogasasTrigeneration119
6.4BiogasasaTransportationFuels120
6.5UseofBiogasinReciprocatingEngine121
6.6SparkIgnitionGasEngine123
6.7UseofBiogasinGenerator124
6.8UseofBiogasinGasTurbines125
6.9UsageofBiogasinFuelCell125
6.10HydrogenProductionfromBiogas125
6.11BiogasCleaningforitsUtilization125
6.11.1CarbonDioxide125
6.11.2Water126
6.11.3HydrogenSulfide126
6.11.4OxygenandNitrogen126
6.11.5Ammonia127
6.11.6VolatileOrganicCompounds127
6.11.7Particles127
6.11.8FoamsandSolidParticles127
6.12DifferentApproachesforH2 SRemoval128
6.12.1IronSponge128
6.12.2ProprietaryScrubberSystems129
6.12.3FerricChlorideInjection129
6.12.4BiologicalMethod130
6.13DifferentApproachesforMoistureReduction130
6.13.1CompressionorCondensation130
6.13.2Adsorption130
6.13.3Absorption130
6.14SiloxaneRemoval131
6.14.1GasDrying131
6.15CO2 Separation132
6.15.1CryogenicTechnique132
6.15.2WaterScrubber133
6.15.3Adsorption133
6.15.4MembraneSeparation134
6.16Conclusion135 References136
7DigestatefromAgriculturalBiogasPlant–PropertiesandManagement141 WojciechCzekała
7.1Introduction141
7.2DigestatefromAgriculturalBiogasPlant–Production,Properties, andProcessing142
7.2.1Production142
7.2.2Properties142
7.2.3Processing144
7.3DigestatefromAgriculturalBiogasPlant–Management145
7.3.1RawDigestateFertilization145
7.3.2LiquidFractionManagement146
7.3.3SolidFractionManagement147
7.3.4EnergyManagementoftheSolidFraction149
7.4Conclusion150 References150
8EnvironmentalAspectsofBiogasProduction155 YelizavetaChernysh,ViktoriiaChubur,andHynekRoubík
8.1Introduction155
8.2ImpactofFarmsandLivestockComplexesontheEnvironment157
8.3TheEnvironmentalBenefitsofBiogasProduction158
8.4EnvironmentalSafetyoftheIntegratedModelofBioprocessesof HydrogenProductionandMethaneGenerationintheStagesof AnaerobicFermentationofWaste162
8.5LifeCycleAssessmentforBiogasProduction165
8.6EnvironmentalIssueofBiogasMarketinUkraine–CaseStudy167
8.7Conclusion172 References172
9HybridEnvironmentalandEconomicAssessmentofBiogasPlantsin
IntegratedOrganicWasteManagementStrategies179 AmalElfeky,KaziFattah,andMohamedAbdallah
9.1Introduction179
9.2Methodology180
9.2.1Overview180
9.2.2WasteManagementScenarios181
9.2.3LifeCycleAssessment182
9.2.3.1GoalandScopeDefinition182
9.2.3.2InventoryAnalysis183
9.2.3.3ImpactAssessment183
9.2.3.4Interpretation184
9.2.4LifeCycleCosting184
9.2.5Eco-EfficiencyAnalysis185
9.2.6CaseStudy:TheUAE185
9.3ResultsandDiscussion185
9.3.1MaterialandEnergyRecovery186
9.3.2LifeCycleAssessment188
9.3.2.1OverallImpactAssessment188
9.3.3LifeCycleCosting190
9.3.3.1CostandRevenueStreams190
9.3.3.2NetPresentValue191
9.3.4Eco-EfficiencyAnalysis192
9.4Conclusion193 References193
10ReductionoftheCarbonFootprintinTermsofAgriculturalBiogas Plants195 AgnieszkaWawrzyniak Acronyms195 10.1Introduction196
10.1.1ManureManagementandBiomethanePotentialinPoland andEUCountries196
10.1.2SubstratesUsedforBiogasPlantsinPoland196
10.1.3GHGEmissionsfromAgricultureandBiogasPlantsasTool foritsReduction198
10.2MethodologyofCF201
10.2.1GHGFluxesfromAgricultureandToolsforits Calculations202
10.2.2SystemBoundariesforBiogasPlantandDataCollection203
10.3LifeCycleCO2 FootprintsofVariousBiogasProjects–Comparison withLiteratureResults204
10.4Conclusions207 References207
11FinancialSustainabilityandStakeholderPartnershipsofBiogasPlants211 To-HungTsui,LeZhang,JonathanT.E.Lee,YanjunDai,andYenWahTong 11.1Introduction211
11.2BasicTechnologicalFactors212 11.3EconomicEvaluationandFailures214
11.3.1InvestmentRisksforFixedAssets214
11.3.2FailuresandIntervention215
11.4StakeholdersPartnershipandCo-governance216
11.4.1Government216
11.4.2ConsultantandConstructor216
11.4.3SourceofWasteStreams217 11.4.4CustomersforEnergyandResource217 11.5SummaryandOutlooks217 Acknowledgments218 References218
12MeasuringtheResilienceofSupplyCriticalSystems:TheCaseofthe BiogasValueChain221
RaulCarlssonandTatianaNevzorova 12.1Introduction221 12.2Background222 12.3Methodology223
12.4MeasurementScheme224
12.4.1IntroductiontotheMeasurementConcept224
12.4.2MeasuringManagementSystemResilience227
12.4.3MeasuringtheResilienceofPhysicalResourcesandAssets229
12.4.4TotalSystemResilience230
12.4.5ApplyingtheSystemResilienceModeltotheBiogasValue Chain231
12.4.5.1AnalysisofTwoSupplyChainsWithout Disruptions231
12.4.5.2DisruptingScenarioswithParametrizedResilience Functions233
12.4.5.3AnalysisofTwoSupplyChainswithDisruptions234 12.5ConclusionandRecommendations239 References240
13TheoryandPracticeinStrategicNichePlanning:ThePolish BiogasCase243 SteliosRozakis,KaterinaTroullaki,andPiotrJurga 13.1Introduction243
13.1.1ThePromisingPotentialofBiogasTransitioninCentral EasternEuropeanCountries243
13.1.2State-of-the-ArtResearchforNavigatingSustainability Transitions245
13.1.3ChapterOrganization246
13.2MainConceptualFrameworksforStudyingSustainability Transitions246
13.2.1StrategicNicheManagement(SNM)246
13.2.2Multi-LevelPerspective(MLP)247
13.2.3TransitionManagement(TM)248
13.2.4TechnologicalInnovationSystems(TIS)248
13.3StudyingBiogasfromaSustainabilityTransitionsPerspective249
13.3.1Landscape,Regime,andNicheDynamics249
13.3.2PolicyCoherenceforNicheDevelopment250
13.3.3TransitionPathways252
13.3.4SocialNetworkAnalysis252
13.4StrategicNichePlanningforSustainableTransitions255
13.4.1MethodologicalSteps255
13.4.2CaseStudy:BiogasSectorinPoland259
13.5StrategicPropositionsandConcludingComments261
13.5.1ResearchandDevelopment261
13.5.2EducationActivity–EnhanceBrokerage271
13.5.3Networking-Clusters271
13.5.4ResourceMobilization271
13.5.5ElaborateLegislation272
13.5.6Legitimation272
13.5.7IncentivesforMarketPenetration272
13.5.8DemandPullActionsandRuralDevelopment273
13.6Conclusion273 References274
14SocialAspectsofAgriculturalBiogasPlants279 WojciechCzekała 14.1Introduction279
14.2TheBenefitsofAgriculturalBiogasPlantsforSociety280
14.2.1BiogasPlantasaRenewableEnergyProductionFacility280
14.2.2ReducingtheNegativeImpactofWasteontheEnvironment280
14.2.3CreateMarketsforSubstratesUsedinBiogasProduction281
14.2.4IntegrationwithAgro-IndustrialPlants281
14.2.5ProductionandUseofElectricity282
14.2.6ProductionandUseofHeat282
14.2.7PossibilityofBiomethaneProduction283
14.2.8LocalFuelinDevelopingCountries283
14.2.9ProductionofValuableFertilizer284
14.2.10CreatingNewJobsfortheLocalCommunity284
14.2.11DevelopmentofNearbyInfrastructureandCompanies285
14.2.12TaxRevenuestotheBudgetofLocalGovernmentUnits285
14.3SocialAcceptabilityofAgriculturalBiogasPlants285
14.3.1FearofSomethingNew286
14.3.2ConcernsAboutUnpleasantOdors286
14.3.3ConcernsAboutContaminationofSoilsandGroundwater WhenUsingDigestateasFertilizer286
14.3.4ConcernsAboutDecliningPropertyValuesAroundBiogas Plants287
14.3.5ConcernsAbouttheDestructionofAccessRoads287 14.4Conclusion287 References288
15PracticesinBiogasPlantOperation:ACaseStudyfromPoland291 TomaszJasi ´ nski,JanJasi ´ nski,andWojciechCzekała 15.1Introduction291
15.2LegalAspectsRelatedtoRunningaBusinessintheFieldofBiogas ProductionandWasteManagement292
15.2.1IntegratedPermitorWasteProcessingPermit293
15.2.2ApprovalofthePlantbyVeterinaryServicesfortheDisposal ofWasteofAnimalOrigin294
15.2.3PermittoPlaceDigestateontheMarket295
15.2.4PermittoIntroducetotheElectricityDistributionNetwork296
15.3BiogasPlantComponents:ACaseStudyfromPoland297
15.3.1HallforReceivingandProcessingSlaughterhouseWaste297
15.3.2SubstrateStorageYard297
15.3.3SolidSubstrateDispenser297
15.3.4ReceivingBufferTankforLiquidSubstrates298
15.3.5SolidSubstrateBufferTank298
15.3.6MixingBufferTank298
15.3.7BufferandMixingTank298
15.3.8TechnologicalSteamGenerator298
15.3.9MainPumpingStation299
15.3.10First-stageFermentationTanks299
15.3.11Second-stageFermentationTank(3900m3 )withBiogas Tank(1800m3 )300
15.3.12CondensingCircuit301
15.3.13BiogasRefiningSystem301
15.3.14CogenerationModules301
15.3.15DigestateStorageReservoirs301
15.3.16BiogasTorch302
15.3.17Biofilter302
15.4FunctioningofaBiogasPlantProcessingProblematicWaste:ACase StudyfromPoland302
15.4.1SearchingandObtainingSubstrates303
15.4.2Receiving,Storage,andProcessingoftheSubstrate,Feeding ofRawMaterials304
15.4.3EnergyProductionandBiogasManagement305
15.4.4DigestateManagement306
15.4.5ManagementofanAgriculturalBiogasPlant307
15.5Summary308
ListofContributors
MohamedAbdallah DepartmentofCivilandEnvironmentalEngineering,Universityof Sharjah,Sharjah,UnitedArabEmirates
MuhammadArslan DepartmentofEnergySystemsEngineering,Universityof Agriculture,Faisalabad,Pakistan
RaulCarlsson CertificationDevelopmentUnit,RISEResearchInstitutesofSweden, Jönköping,Sweden
YelizavetaChernysh FacultyofTropicalAgriSciences,DepartmentofSustainable Technologies,CzechUniversityofLifeSciencesPrague,Suchdol,Czechia DepartmentofEcologyandEnvironmentalProtectionTechnologies,FacultyofTechnical SystemsandEnergyEfficientTechnologies,SumyStateUniversity,Sumy,Ukraine
ViktoriiaChubur FacultyofTropicalAgriSciences,DepartmentofSustainable Technologies,CzechUniversityofLifeSciencesPrague,Suchdol,Czechia DepartmentofEcologyandEnvironmentalProtectionTechnologies,FacultyofTechnical SystemsandEnergyEfficientTechnologies,SumyStateUniversity,Sumy,Ukraine
WojciechCzekała DepartmentofBiosystemsEngineering,Pozna ´ nUniversityofLife Sciences,Pozna ´ n,Poland
YanjunDai EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII, CampusforResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore SchoolofMechanicalEngineering,ShanghaiJiaoTongUniversity,Shanghai,China
RenjieDong CollegeofEngineering,ChinaAgriculturalUniversity,Beijing,China
NalokDutta DepartmentofBiochemicalEngineering,UniversityCollegeLondon, London,UK
BioproductsSciencesandEngineeringLaboratory,WashingtonStateUniversity,USA
AmalElfeky DepartmentofCivilandEnvironmentalEngineering,UniversityofSharjah, Sharjah,UnitedArabEmirates
KaziFattah DepartmentofCivil,Environmental,andArchitecturalEngineering, UniversityofKansas,Kansas,UnitedStatesofAmerica
LikuiFeng StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
JanJasi ´ nski DepartmentofBiosystemsEngineering,Pozna ´ nUniversityofLife Sciences,Pozna ´ n,Poland
TomaszJasi ´ nski TomaszJasi ´ nskiBiogasConsulting,Nowe,Poland
MengmengJiang CollegeofEngineering,ChinaAgriculturalUniversity,Beijing,China
PiotrJurga DepartmentofBioeconomyandSystemsAnalysis,InstituteofSoilScience andPlantCultivation,Pulawy,Poland
MuhammadU.Khan DepartmentofEnergySystemsEngineering,Universityof Agriculture,Faisalabad,Pakistan
MartynaKuli ´ nska DepartmentofBiosystemsEngineering,Pozna ´ nUniversityofLife Sciences,Pozna ´ n,Poland
JonathanT.E.Lee NUSEnvironmentalResearchInstitute,NationalUniversityof Singapore,Singapore
EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII,Campusfor ResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore
JianjuLi StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
EeY.Lim DepartmentofChemicalandBiomolecularEngineering,NationalUniversity ofSingapore,Singapore
YuLiu StateKeyLaboratoryofUrbanWaterResourcesandEnvironment(SKLUWRE), SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
Kai-CheeLoh EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII, CampusforResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore DepartmentofChemicalandBiomolecularEngineering,NationalUniversityofSingapore, Singapore
AleksandraŁukomska DepartmentofBiosystemsEngineering,Pozna ´ nUniversityof LifeSciences,Pozna ´ n,Poland
TatianaNevzorova CertificationDevelopmentUnit,RISEResearchInstitutesof Sweden,Stockholm,Sweden
WeiQiao CollegeofEngineering,ChinaAgriculturalUniversity,Beijing,China
HynekRoubík FacultyofTropicalAgriSciences,DepartmentofSustainable Technologies,CzechUniversityofLifeSciencesPrague,Suchdol,Czechia
SteliosRozakis BiBELab,DepartmentofChemicalandEnvironmentalEngineering, TechnicalUniversityofCrete,Chania,Greece
AbidSarwar DepartmentofIrrigationandDrainage,UniversityofAgriculture, Faisalabad,Pakistan
YapengSong CollegeofEngineering,ChinaAgriculturalUniversity,Beijing,China
YenWahTong NUSEnvironmentalResearchInstitute,NationalUniversityof Singapore,Singapore
EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII,Campusfor ResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore DepartmentofChemicalandBiomolecularEngineering,NationalUniversityofSingapore, Singapore
KaterinaTroullaki BiBELab,DepartmentofChemicalandEnvironmentalEngineering, TechnicalUniversityofCrete,Chania,Greece
To-HungTsui NUSEnvironmentalResearchInstitute,NationalUniversityofSingapore, Singapore
EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII,Campusfor ResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore DepartmentofEngineeringScience,UniversityofOxford,Oxford,UK
SimonM.Wandera DepartmentofCivil,Construction&EnvironmentalEngineering, JomoKenyattaUniversityofAgriculture&Technology,Nairobi,Kenya
AgnieszkaWawrzyniak DepartmentofBiosystemsEngineering,Pozna ´ nUniversityof LifeSciences,Pozna ´ n,Poland
LiangliangWei StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
XinhuiXia StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
HangYu StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
JingxinZhang EnergyandEnvironmentalSustainabilityforMegacities(E2S2) PhaseII,CampusforResearchExcellenceandTechnologicalEnterprise(CREATE), Singapore
China-UKLowCarbonCollege,ShanghaiJiaoTongUniversity,Shanghai,China
LeZhang NUSEnvironmentalResearchInstitute,NationalUniversityofSingapore, Singapore
EnergyandEnvironmentalSustainabilityforMegacities(E2S2)PhaseII,Campusfor ResearchExcellenceandTechnologicalEnterprise(CREATE),Singapore DepartmentofResourcesandEnvironment,SchoolofAgricultureandBiology,Shanghai JiaoTongUniversity,Shanghai,China
WeixinZhao StateKeyLaboratoryofUrbanWaterResourcesandEnvironment (SKLUWRE),SchoolofEnvironment,HarbinInstituteofTechnology,Harbin,China
1 AnaerobicDigestionProcess andBiogasProduction
LiangliangWei,WeixinZhao,LikuiFeng,JianjuLi,XinhuiXia, HangYu,andYuLiu
StateKeyLaboratoryofUrbanWaterResourcesandEnvironment(SKLUWRE),SchoolofEnvironment, HarbinInstituteofTechnology,Harbin,China
1.1Introduction
Theincreasingamountoforganicwastesworldwidehasbecomeproblematicformost countriesduetothecontinuousdeteriorationoflandandwaterconditions,whichposes seriousriskstothesafetyofourcommunity[1].Moreover,theimpropertreatmentofthese organicwastesmightleadtotheundesiredreleaseofhugegreenhousegases(GHGs)into theatmosphere[2,3].ItwasestimatedbytheIntergovernmentalPanelonClimateChange (IPCC)andUSEnvironmentalProtectionAgency(USEPA)thattheglobalanthropogenic methaneemissionfrommunicipalsolidwastes(MSWs)reached1077millionmetricton ofCO2 equivalentin2020andisexpectedtoincreaseby17%intheyear2030.Mitigation practiceshaveforcedglobalactiontoadoptatechnologythatcanaddressanthropogenic methaneemissions[4].Numerousavailablemitigationopportunitiescurrentlyincludethe treatmentoftheorganicportionofMSWinacontrolledfacilityandrecoveringmethaneas afuelforon-siteoroff-siteelectricitygeneration[5].
EnergygenerationfromtheMSWandtheotheralternativesourceswillbenefitclimate changemitigationandminimizethealarmsposedtotheenvironment[6].Therehas beenahighuptakeofrenewableenergytechnologies(RETs)worldwidetodealwith thedetrimentaleffectspausedbyfossil-relatedenergygenerationtechnologies.Fora purposeofincreasingtheenergyaccessibilitywhilesimultaneouslyrestrictingthe
BiogasPlants:WasteManagement,EnergyProductionandCarbonFootprintReduction, FirstEdition.EditedbyWojciechCzekała ©2024JohnWiley&SonsLtd.Published2024byJohnWiley&SonsLtd.
worldwidetemperatureincreasedwithin2 ∘ Cbefore2050,adoptionofRETsshouldbe highlyencouragedandraisedsignificantly.Thisgrowingimpetusforalternativeavenues forrenewableenergydemandstheconsiderationofdifferentfeedstocks,exploringofnovel techniques,andimprovementsofexistingtechnologies.
Bioenergyhasbeenregardedasthemostsubstantialrenewableenergysourceduetoits cost-effectiveadvantagesandgreatpotentialforsubstitutingnonrenewablefuels.Bioenergy derivedfrombiomassmaterials,suchasbiologicalorganicmatterobtainedfromplants oranimals,isrenewableandgreen.Generally,thosebiomassenergysourcesincludebut arenotlimitedtoterrestrialplants,aquaticplants,timberprocessingresidues,MSWs, animaldung,sewagesludge,agriculturalcropresidues,andforestryresidues.Undoubtedly, bioenergyisoneofthemostversatilerenewableenergiesbecauseitcanbemadeavailableinsolid,liquid,and/orgaseousforms.Differentavenuescanbeexploredtoharvest energyfrombiomassmaterials.Biomethanehasahighheatingvaluerangingbetween50 and55MJm 3 andalowheatingvaluerangingbetween30and35MJm 3 [7].
Anaerobicdigestion(AD)ispracticedextensivelyforthetreatmentofbiodegradable wasteforbiomethanegeneration[8].Thistechnologyhasthecapabilityofmanagingthe typicalorganicwastessuchasfoodwaste,lignocellulosicbiomassandresidues,energy crops,andtheorganicfractionofmunicipalsolidwaste(OFMSW)[9],anditsenvironmentallysoundfeaturesattractedworldwideattentionforbiogasproduction.ADisamicrobedriven,multiphase,andcomplexbiochemicalprocess,andfourtypicalbiochemicalphases suchashydrolysis,acidogenesis,acetogenesis,andmethanogenesisareinvolvedinits wholeprocess.Organicmattercouldbeefficientlymetabolizedbybacteriaandarchaea andfinallyconvertedintomethaneandcarbondioxide[10,11].However,ADprocesses arealwayslimitedbythreemainfactors:(i)hydrolysisofsubstratesistherate-limiting factorforthebioconversionphase;(ii)inefficientutilizationofkeyintermediatessuchas propionicandbutyricacid;(iii)slowgrowthofanaerobesofmethanogenesis[12],and finallyleadtoalowbiomethanerecoveryrateduringtheirpracticaloperation[13].Thus, theadvancementsintheADprocessarelargelyaimedtowardonegoal:improvingbiogas productionandrecovery.
ThereiscurrentlyconsiderablepotentialforbiogastechnologytobedevelopedasaRET thataddressesenergyandenvironmentalissues.Biogasisacriticaltechnologythatprovidesrenewableenergyfromprocessingavarietyofdigestiblebiomasstypes.Substrates suchasstraw,forestryresidues,animalandpoultrymanure,andotherorganicwastescan betreatedwithinADsystems.Thepurifiedbiomethanecanbeintegratedintoconventional fossilenergysupplysystemsandguaranteetheADtechnologyinenergytransformation andecologicalcivilizationconstruction.However,thebiogasindustryfacesmanychallenges,includinglowgasproductivity,shortbiogastanklife,highdeteriorationratesof digesters,difficultyindigestionresidueutilization,andlimitedeconomicbenefits[14,15]. Toimprovethebiogasandhighlightitsroleinenergyandenvironmentalproblem-solving, itisnecessarytodevelopnewapproachesforthepurposeofextendingtheindustrialchain andfurtherexploringnewmodelsthatcanpromotethecommercialization.
1.2BasicKnowledgesofADProcessesandOperations
1.2.1FundamentalMechanismsandTypicalProcessesofAD AD,fullmicrobiologicaldegradationprocessunderanaerobicconditions,representsone ofthemostpromisingprocessestoconvertdiverseorganicsubstrates(animalmanure,
Carbohydrates, proteins, fats, and other complex organic substrates Sugars, amino acids, and fatty acids
Figure1.1 Generalbiochemicalprocessinvolvedinanaerobicdigestion.Source:D’Silvaetal.[17]/with permissionofElsevier.
foodwaste,MSW,andlignocellulosicbiomassasagriculturalwaste)intoenergycarriers (producedbiogasmainly55–75%CH4 and25–45%CO2 )[16].
Microbialecologyinanaerobicdigestersisquitecomplex,anddifferentbacterialand archaealcommunitiesareinvolvedinthedigestionprocess.TheADprocessiscomposed offourmainsteps,namelyhydrolysis,acidogenesis,acetogenesis,andmethanogenesis (Figure1.1).Thehydrolysisprocessistheprimarystep(stageI)inADwhereorganicpolymers(i.e.cellulose,lipids,carbohydrates,polysaccharides,proteins,andnucleicacids)are hydrolyzedintomonomers,simplesugars,saccharides,peptides,glycerol,aminoacids,and otherhigherfattyacids,whichcouldbesummarizedinEq.(1.1):
Hydrolyticbacteria,alsoknownasprimaryfermentingbacteria,arefacultativeanaerobesthathydrolyzethesubstratewithextracellularenzymes.Awiderangeofenzymes,i.e. cellulases,hemicellulases,proteases,amylases,andlipases,weregeneratedinthisstage andplayedagreatroleinthesubstratedegradation[18].Undoubtedly,thegenerationofthe aforementionedenzymesenhancedthewholehydrolysis.Bycontrast,thelackofthesuitableenzymeswouldnegativelyaffectthebiogasgeneration,forinstance,thehydrolyzation oflignocellulosicsubstratesbecomestherate-limitingstepoftheADprocess[18].During acidogenesis(stageII),primaryfermentativebacteriaconverthydrolysisproductsinto volatilefattyacids(VFAs),includingacetate,propionate,butyrate,valerate,andotheracids (i.e.lactate,succinate,andalcohols).Acidogenicbacteriaareabletometabolizeorganic
compoundsataverylowpHaround4.Methanogenicmicroorganismscannotdirectly useallproductsfromtheacidogenicstep.Exceptforacetate,H2 andCO2 andsomeother micromolecularorganicacidswereabundantlygeneratedduringtheso-calledacetogenic phase(stageIII)bysecondaryfermentingbacteria,alsocalledobligatehydrogen-producing bacteria(OHPB).However,thethermodynamicsofthesereactionsareunfavorable,and thesemicroorganismscanonlyliveinsyntrophywithend-productusers,i.e.methanogens. Themethanogenicstep(stageIV)correspondstothefinalconversionofacetate,carbondioxide(CO2 ),andhydrogen(H2 )intobiogas,andtheobligateanaerobicarchaeaof hydrogenotrophicandacetoclasticmethanogensabundantlyexistinthedigestersandcould transformthemixtureofCO2 /H2 andacetateintomethane.Specifically,hydrogenotrophic microorganismsconvertH2 andCO2 ,producedbyfermentativebacteria,intoCH4 andkeep thereactorunderalowhydrogenpartialpressureandthusenhancedthegrowthofacetogenicbacteria.Therelativeabundanceofhydrogenotrophicandacetotrophicisvariable accordingtoenvironmentalfactors(i.e.acetate,ammonia,hydrogen,andhydrogensulfide concentrations),andoperationalconditions(i.e.hydraulicretentiontime[HRT],pH,type ofsubstrate,andsourceofinoculum),aswellassolidcontents[19].Ithasbeenreported thatthehydrogenotrophicmethanogens(i.e. Methanoculleus and Methanobacterium)are predominatedduringthestart-upofanaerobicdigestersandleadtoasubsequentdeclineof theH2 concentration;Then,ashiftofthemethanogensintotheacetoclasticmethanogens (i.e. Methanosarcina and Methanosaeta)wereobservedafterthestabilizationofthereactor[20].Inaddition,ahighconcentrationofammoniaoftheanaerobicdigesterbenefited forthegrowthofhydrogenotrophicmethanogensinmesophilicanaerobicdigestors[21], andapproximately65–70%ofthemethanegenerationwascloselyrelatedtothedegradationofacetate;otherwise,theoxidationofacetatetoH2 andCO2 isthemainpathwayin theabsenceofacetoclasticmethanogens(suchas Methanosaeta sp.)[22].
1.2.2FactorsAffectingtheADProcessofBiogasProduction
1.2.2.1Temperature
Threedifferenttemperatureregimes,namelypsychrophilic,mesophilic,andthermophilic conditions,withvariedoptimumtemperaturerangesforthedominationofdifferent strainsofmethane-formingbacteria,weretraditionallyusedinanaerobicdigesters[23]. Specifically,psychrophilicdigestersusuallyoperateatabout25 ∘ C,whereasmesophilic onesoperateataround35 ∘ Candthermophiliconesataround55 ∘ C.Generally,the metabolicactivityandbioconversionrateofmicroorganismsathighertemperatureare usuallyhigherthanthatatlowertemperature.However,themuchmoreenergyisrequired formaintainingahightemperatureinthefermenter,whichincreasescostinpractical operation[23].Forinstance,amuchhigherdegradationrateoffattyacidswasobservedfor thedigesteroperatedunder55 ∘ Cwitha11HRTthanthatoperatedunder38 ∘ Ccondition witha27dayHRT[23].Similarly,anincreaseof54–61%inCH4 yieldfromalgal remnantswasobservedwhenthetemperatureincreasedfrom25to35 ∘ C[24].Inaddition, someoftherecentworksalsorevealedthatreportedthatthevariationofoperational temperature,evenunderaverysmallrange,woulddeclinethebiogasproductionrateofthe digesters[25],andthefluctuationofthetemperatureeven1 ∘ Cperdaywoulddeteriorate theoperation[26].
1.2.2.2pH
OperationalpHmightbeanothermainfactorthatwouldsignificantlyaffecttheperformanceofthedigesters,andthemostfavorablerangeofpHtoachievemaximalbiogasyield inADis6.8to7.2[23].Specifically,themethanogenicbacteriaareextremelysensitiveto pHfluctuations,andtheirpreferredpHwasaround7.0,andthegrowthrateofmethanogens wasseriouslyinhibitedoncethepHdeclinedto <6.6[27].Acid-formingbacteriaareless pH-sensitive,andtheoptimalpHforhydrolysisandacidogenesisisbetween5.5and6.5, despitetheirtoleratedpHrangedfrom4.0to8.5[26,27].Therefore,somedesignersprefertheisolationofthehydrolysis/acidificationandacetogenesis/methanogenesisprocesses intotwoseparatestages[27].Atthebeginningofthefermentation,thesignificantaccumulationofacidsandCO2 ,asaconsequenceofthegrowthofacidogensandacetogens, leadstoasignificantdeclineinthepH.Afterward,theconsumptionoftheseacidsby themethane-producingbacteriawouldmaintainthedigesterunderastablecondition[23] Excessivefattyacids,hydrogensulfide,andammoniaaretoxiconlyintheirnonionized forms(FAandH2 S–pHbelow7,NH3 –pHabove7);thus,theproportionaldistributionof ionizedandnonionizedformsofinhibitorsofmethanogenesiswasessentialforthestable operationofthedigesters.
1.2.2.3OrganicLoadingRate(OLR)
Organicloadingrate(OLR),generallydefinedaskilogramsofVSloadedpervolumeof digesterperday,ishenceconsideredasoneofthemainparametersforstableoperationof ADsystems[28].Theproductionofbiogasandmethaneincontinuoussystemsishighly dependentontheOLRvalue(relatedtotheTSinthedigesterandthecompositionof feedstock),andthevariationoftheOLRwouldleadtosignificantvariationofthemethane yieldsandsystemstability.TherecentworkofNizamiandMurphy(2010)[29]stated thattheoptimumOLRoftheanaerobicdigestersrangedfrom12to15kgVSm 3 d 1 forcornsilage,while8.5kgVSm 3 d 1 forothersubstrates[30]clearlydemonstrated thattheOLRvaluesarehighlydependentonthefeedstockcompositions.Practically,the accumulationofinhibitorycompounds,suchasVFAorammonia,negativelyaffected theincreasingoperationalOLRvaluesofthedigesters[31].Manyauthorshighlightthe needforunderstanding.Thus,OLRneedstobecarefullyselectedbysimultaneouslyconsideringthefeedstockcharacteristics,inhibitorycompoundexistences,andco-digestion opportunities,tomaximizewastetreatmentcapacityandenhancetherenewableenergy productivity.
1.2.2.4Carbon–NitrogenRatio
Feedstocktotalorganiccarbon(TOC),totalnitrogen(TN)andtheirratioarealsocritical forthestableoperationoftheADsystems.Theadditionofco-substrates,forthepurpose ofelementbalance,hasbeenregardedasoneofthemostcommonpracticesforapurpose ofachievingstableco-digestion[32],andtheoptimalC:Nratioofdigesterswasalways rangedfrom20to30[33].ThenitrogenintheADreactorismainlyderivedfromproteins, anditplaysakeyroleinmicrobialgrowth.However,alowC:Nratiointhedigesterssystem (highamountofnitrogen)canproduceanammoniaaccumulation,subsequentlyaffecting thebiogasandmethaneyieldsandeventuallycausingthesystemtodeteriorate[34].Thus,
theadditivepaperwasteoragriculturalwastehasbeentraditionallyappliedtoincreasethe feedstock’scarboncontent[35].
1.2.2.5Inoculum-to-SubstrateRatio(ISR)
Inoculum-to-substrateratio(ISR),whichdeterminestheinitialratiobetweenmicrobial populations,isanimportantparameterforstartingupofanaerobicdigesters[36].Themore theinoculum,thehigherthenumberofmethanogensintheanaerobicdigestersandthebetterthebufferingcapacity.Raposoetal.usedsunfloweroilcakeasthesubstratetoexplore theeffectofdifferentinoculationratesonAD[37],andtheyfoundthatthevolatileacids werenotaccumulatedundertheoperationalconditionsofISR1.0–3.0,whereassignificant volatileacidaccumulationoccurswhentheinoculationrateislessthan1.0.Forinstance, theratiooftotalvolatileacidtototalalkalinitywasmuchhigherthanotherexperimental groupsoncetheinoculationratiodeclinedto0.5.
1.2.2.6SolidsConcentration
Thereducedwatercontentoftheorganicwasteswithinthedigestersisgenerallyregarded asthemainreasonforthedifficultyinthegasandliquiddiffusionandtheaccumulationof inhibitorsandinturnreducesthesubstrateavailabilityandaffectstheirmetabolism[38]. Anumberofstudiesreportedthatanincreaseinthewatercontentofsubstrateincreases themethaneyieldingandalsoleadstoanexcellenthomogenizationoftheADsystems, efficientelementdiffusion,andeffectiveinteractionbetweenmicroorganismsandnutrients. Inaddition,therecentworkofLeHyaricetal.(2012)[39]reportedthattherewasalinear increaseinthespecificmethanogenicactivitywiththeincreaseinwatercontent,ascribing totheimprovementofthehomogeneityofthedigestionreactors[40].
1.2.2.7HydraulicRetentionTime(HRT)
RetentiontimeofthedigestersreferstobothHRTandsolidretentiontime(SRT)andwas ananotherimportantparameterusedfordesigningandoptimizationofanaerobicdigesters (representedinEqs.(1.2)and(1.3))[41].Specifically,HRTrepresentstheretentiontime oftheliquidphase,whereasSRTdenotestheretentiontimeofthemicrobialcultureinthe digester.Assumingthatthefeedstockandmicrobialmixedculturesexistedinthesame phaseintheanaerobicdigester,theHRTvalueofthedigestionsystemequalstoSRT.For example,intheADsystems,usingfoodwaste,kitchenwaste,andMSWasthesubstrates, theHRTofthesystemisessentiallySRT.Incontrast,theinteractionbetweensolidsand microbialculturesisbiphasicforthedigestersusingwaste-activatedsludgeandprimary sludgeassubstratesandleadstoquitedifferentdistributionofHRTandSRT:
where V referstotheindividualreactorvolume(m3 ), Q istheinfluentflowrate(m3 d 1 ), X presentsthemixedliquidsuspendedsolidsinanindividualreactor(mgL 1 ), Qx denotes
