LCA-產(chǎn)品生命周期分析解讀課件

LifeCycleAssessment LCAWhyLCA?Quantifytheenvironmentalimpactofaproductorprocess*AnswerquestionsaboutproductlifecyclesComparetwoalternatives-whichisgreener?Identifytheharmfulstagesofthelifecycle*orcarryoutaqualitativeassessment–quickbutsubjectiveTheLCAsystem+TransportExtractionofmaterialsProcessingofmaterialsManufactureandassemblyUseandmaintenanceReuseandrecyclingWastemanagementENERGYRAW

MATERIALSEMISSIONSTOAIREMISSIONSTOWATERSOLID

WASTEUTILITY(FUNCTION)systemboundaryStagesofanLCA:1–goal,scopeandunitsExample–electricanddisposablerazors-whyarewedoingit?-whatisthesystem?-whatisthefunctionalunit?-toimprovedesigns-manufacture,useanddisposal-1year’scloseshavesat1perdayThesystemprocesses-flowchartsExample:woodentableIdentifiesthesystemboundaryFlowsinandout–materials,energy(E)andtransportuse(T)ShowsalltheprocessesinvolvedinthelifecycleExcludesselectedprocesses–e.g.minorones,orunknownShowsend-of-lifealternatives,withprobabilityFlowchartexercise1:electricshaverSteelproductionManufactureandassemblyDistributionUseShaverdisposalLandfillEMISSIONSTOAIREMISSIONSTOWATERSOLID

WASTEUTILITY(shaving)systemboundaryUKElec.generationETransportTPolymerproductionElectronicsproductionRecycling30%70%EEETPackagingproduction…what’smissing?TFlowchart2:disposablerazor&bladesSteelproductionManufactureandassemblyDistributionUseRazordisposalLandfillEMISSIONSTOAIREMISSIONSTOWATERSOLID

WASTEUTILITY(shaving)systemboundaryUKElec.generationETransportTPolymerproductionETPackagingproduction…what’smissing?TBladesEHotwaterSoapThefunctionalunit MilkpackagingmethodsGoalofstudy:tocomparepackagingmaterialsanddesignsfromdairytoconsumer,includingdisposal.Functionalunit:1000litresofpackedmilk,foronetrip.LightbulbsGoal:tocomparealternativelightbulbdesignsforconsumers.Functionalunit:10,000hoursilluminationatagivenbrightness(xlumens).CommutingGoal:tocomparedifferentmodesoftransporttowork,e.g.bus,bike,carFunctionalunit:1year’scommuting10km/dayby100peopleExercises:Foodtransport(tocompareroadandrailforfoodfromfarmtosupermarket)Housedesign(tocomparetheenergyandmaterialsuseofalternativedesigns)Refrigerators(tocomparedifferentmodelsofvarioussizes)Foodtransport:100ton.kmHousedesign:500m2dwellinginaspecifiedclimateRefrigerator:2m3volume,cooledby20for1year,5kgfoodadded/weekStage2:InventoryanalysisAcompleterecordofquantitiesof:Inputsofenergy,fuel,etc.RawmaterialsbytypeTransportused(hencefuels,energy,etc)Outputstoair,water;solidwaste-manychemicalslistedhereTheinventoryisnormallyaspreadsheetortableofmanyentriesExample:shavingsystemsInventoryofprocessesincludes:Polymersfromoil;copper;etc.transportenergyandemissionsdisposal–solidwasteandairpollutionStage3:ImpactassessmentTheinventoryisusuallytranslatedintoasetof

environmentaleffects:Fuels&energyRawmaterials(Land)(Water)SolidwasteAir:CO2,NOX,SOX,etc.Water:Acid,nitrates,phosphates,etc.WasteheatUseofnon-renewableresourcesGlobalwarmingOzonedepletionHumantoxicityEcosystemtoxicityAcidificationEutrophicationCOD,BODinwaterSmogNoise...etc.?Impactassessment-classificationThecorrespondencebetweeninventory(aspects)andeffectsisnotone-to-one:Fuels&energyRawmaterials(Land)(Water)SolidwasteAir:CO2,NOX,SOX,etc.Water:Acid,nitrates,phosphates,etc.WasteheatUseofnon-renewableresourcesGlobalwarmingOzonedepletionHumantoxicityEcosystemtoxicityAcidificationEutrophicationCOD,BODinwaterSmogNoise...etc.ImpactassessmentExampleImpactofelectricshaver:resourcedepletion(oil,copper)globalwarming(CO2)fromelec.toxicityfromtransportemissionsetc.Impactofrazor&blades:globalwarming(CO2,CH4)Eco-toxicityfromwastewaterLandusefromlandfillofwasteinc.packagingetc.Impactassessment-characterisationThetotalsforeacheffectcanthenbeaddedupandcompared:Impactassessment-valuation Thelaststage,optional-andcontroversialIfsubjectivevaluesareplacedonhealth,ecosystems,etc.-thentheimpactscanbevaluedinasingleunitMostcommonexample:DutchEcoindicatormethodsuggestsrelativeimportanceofimpactsthewholeLCAcanbeexpressedintermsofPointsonlyvalidforacountryorregion,e.g.ECgoodforinternalcomparisons;usedbyPhilipsE.g.Electricshaver 250pointstomake,1tocharge =2ptspershaveRazor&blades 30ptshandle,12percartridge =3ptspershaveStage4–interpretationExample:shavingInterpretingthestudy:Electricshaver-majorimpactinmanufactureandcharging,hencelargeGWimpactRazorandblades–morewaste,dependingonassumptionsonbladedurability,methodofheatingwater……h(huán)encebetterunderstandinganddesignideasLCAsoftwareDatabasecontainsinventoryforcommonmaterials,energysources,transporttypesandwastestrategiesdataquali