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Manahan,StanleyE.PRINCIPLESOFINDUSTRIALECOLOGYEnvironmentalChemistryBocaRaton:CRCPressLLC,200017PRINCIPLESOFINDUSTRIALECOLOGY____________________________________________________17.1.INTRODUCTIONANDHISTORYIndustrialecologyisanapproachbaseduponsystemsengineeringandecolo-gicalprinciplesthatintegratestheproductionandconsumptionaspectsofthedesign,production,use,andtermination(decommissioning)ofproductsandser-vicesinamannerthatminimizesenvironmentalimpactwhileoptimizingutilizationofresources,energy,andcapital.1Thepracticeofindustrialecologyrepresentsanenvironmentallyacceptable,sustainablemeansofprovidinggoodsandservices.Themeaningofindustrialecology,arelativelynewconcept,hasbeenoutlinedinabookdealingwiththetopicanditsimplementation.2Industrialecologymimicsnaturalecosystemswhich,usuallydrivenbysolarenergyandphotosynthesis,consistofanassemblyofmutuallyinteractingorganismsandtheirenvironmentinwhichmaterialsareinterchangedinalargelycyclicalmanner.Anidealsystemofindustrialecologyfollowstheflowofenergyandmaterialsthroughseverallevels,useswastesfromonepartofthesystemasrawmaterialforanotherpart,andmaximizestheefficiencyofenergyutilization.Whereaswastes,effluents,andproductsusedtoberegardedasleavinganindustrialsystematthepointwhereaproductorservicewassoldtoaconsumer,industrialecologyregardssuchmaterialsaspartofalargersystemthatmustbeconsidereduntilacompletecycleofmanufacture,use,anddisposaliscompleted.Fromthediscussionaboveandintheremainderofthisbook,itmaybecon-cludedthatindustrialecologyisallaboutcyclizationofmaterials.ThisapproachissummarizedinastatementattributedtoKumarPateloftheUniversityofCaliforniaatLosAngles,“Thegoaliscradletoreincarnation,sinceifoneispracticingindustrialecologycorrectlythereisnograve.”Forthepracticeofindustrialecologytobeasefficientaspossible,cyclizationofmaterialsshouldoccuratthehighestpossiblelevelofmaterialpurityandstageofproductdevelopment.Forexample,itismuchmoreefficientintermsofmaterials,energy,andmonetarycoststobondanewrubbertreadtoalarge,expensivetireusedonheavyearthmovingequipmentthanitistotryto©2000CRCPressLLCseparatetherubberfromthetireandremolditintoanewone.Thebasisofindustrialecologyisprovidedbythephenomenonofindustrialmetabolism,whichreferstothewaysinwhichanindustrialsystemhandlesmaterialsandenergy,extractingneededmaterialsfromsourcessuchasores,usingenergytoassemblematerialsindesiredways,anddisassemblingmaterialsandcomponents.Inthisrespect,anindustrialecosystemoperatesinamanneranalogoustobiologicalorganisms,whichactonbiomoleculestoperformanabolism(synthesis)andcatabolism(degradation).Justasoccurswithbiologicalsystems,industrialenterprisescanbeassembledintoindustrialecosystems.Suchsystemsconsistofanumber(preferablylargeanddiverse)ofindustrialenterprisesactingsynergisticallyand,forthemostpart,witheachutilizingproductsandpotentialwastesfromothermembersofthesystem.Suchsystemsarebestassembledthroughnaturalselectionand,toagreaterorlesserextent,suchselectionhasoccurredthroughouttheworld.However,recognitionoftheexistenceanddesirabilityofsmoothlyfunctioningindustrialecosystemscanprovidethebasisforlawsandregulations(ortherepealthereof)thatgiveimpetustotheestablishmentandefficientoperationofsuchsystems.Thetermsustainabledevelopmenthasbeenusedtodescribeindustrialdevelop-mentthatcanbesustainedwithoutenvironmentaldamageandtothebenefitofallpeople.Althoughthetermhasbecomewidelyused,ithasbeenpointedout3thatsomeconsiderthetermtobe“anoxymoronwithoutsubstance.”Clearly,ifhumankindistosurvivewithareasonablestandardofliving,somethinglike“sustainabledevelopment”mustevolveinwhichuseofnonrenewableresourcesisminimizedinsofaraspossible,andthecapabilitytoproducerenewableresources(forexample,bypromotingsoilconservationtomaintainthecapacitytogrowbiomass)isenhanced.4Thiswillrequiresignificantbehavioralchanges,particularlyinlimitingpopulationgrowthandcurbinghumankind’sappetiteforincreasingconsumptionofgoodsandenergy.17.2.INDUSTRIALECOSYSTEMSAgroupoffirmsthatpracticeindustrialecologythroughasystemofindustrialmetabolismthatisefficientintheuseofbothmaterialsandresourcesconstituteafunctionalindustrialecosystem.Suchasystemmaybedefinedasaregionalclusterofindustrialfirmsandotherentitieslinkedtogetherinamannerthatenablesthemtoutilizeby-products,materials,andenergybetweenvariousconcernsinamutuallyadvantageousmanner.Figure17.1showsthemainattributesofafunctionalindustrialecosystem,which,inthesimplestsense,processesmaterialspoweredbyarelativelyabundantsourceofenergy.Materialsenterthesystemfromarawmaterialssourceandareputinausableformbyaprimarymaterialsproducer.Fromtherethematerialsgointomanufacturinggoodsforconsumers.Associatedwithvarioussectorsoftheoperationarewasteprocessorsthatcantakeby-productmaterials,upgradethem,andfeedthembackintothesystem.Anefficient,functionaltransportationsystemisrequiredforthesystemtoworkefficiently,andgoodcommunicationslinksmustexistamongthevarioussectors.Akeymaterialinthesystemiswater.©2000CRCPressLLCFigure17.1.Majorcomponentsrequiredforanindustrialsystem.Whenthesecomponentsexistsymbioticallyutiliz