Sewage-sludge-handling-with-phosphorus-utilization-–-life-cycle-assessment-of-four-alternatives

SewagesludgehandlingwithphosphorusutilizationelifecycleassessmentoffouralternativesKristinJohanssona,MariaPerzona,MorganFro¨lingb,AgnesMossakowskac,MagdalenaSvanstro¨ma,*aChemicalEnvironmentalScience,ChalmersUniversityofTechnology,SE-41296Go¨teborg,SwedenbLaboratoryforEnergyandtheEnvironment,MassachusettsInstituteofTechnology,77MassachusettsAvenue,Cambridge,MA02139,USAcEnvironmentandDevelopment,StockholmWaterCo.,SE-10636Stockholm,SwedenReceived31January2005;receivedinrevisedform8September2006;accepted1December2006Availableonline15February2007AbstractFourhandlingoptionsforsewagesludgewerestudiedfromanenvironmentalsystem’sperspectiveusinglifecycleassessment.Thestudiedoptionswererestorationofminingareas,compostingwithotherbiomaterialsforuseongolfcourses,hygienisationthroughstorageforagricul-turaluse,andsupercriticalwateroxidationwithphosphorusrecovery.Theresultsarediscussedintermsofimpactonglobalwarming,acidi-fication,eutrophication,andtheuseoffiniteresourcesandprimaryenergy.Averylargeimpactofincludingbiogeochemicalemissionsfromsludgehandlingandspreadingonlandcanbeseen.Systemexpansionsforreplacedartificialfertilizersalsohadamajorinfluenceontheresults.Itisclearthatitisimportantfortheenvironmentaloutcomeofsludgetreatmentoptionsthatbiogeochemicalemissionsfromsludgearemin-imizedandthatnutrientsandotherresourcesareutilizedefficiently.�2006ElsevierLtd.Allrightsreserved.Keywords:Municipalsludgetreatment;Restorationofminingarea;Composting;Agriculture;Supercriticalwateroxidation;SCWO;LCA1.IntroductionLinearmaterialflowsleadtodepletionatthesourceandpollutionatthesink.Theuseofrenewablematerialsanden-ergysourcesinadditiontotheefficientrecoveryofresourcesfromallwasteflowsaresomeofthemeasuresthatneedtobetakeninordertoachievemorecyclicalflowsinsociety.Sew-agesludgeisaflowthathasbeendiscussedinsuchterms.Sludgegeneratedinurbanareasamountstovolumeslargeenoughtobecomeproblematicwithoutproperhandlingoptions.Thepresent25EUmemberstatestogetherproducedaround10milliondrytonnesofsewagesludgein