高负荷复合厌氧氨氧化反应器的性能及其从极端底物抑制的长期恢复2014

Theperformanceofhigh-loadingcompositeanammoxreactoranditslong-termrecoveryfromextremesubstratesinhibitionJianZhao,JianeZuo⇑,PengLi,JiaLinStateKeyJointLaboratoryofEnvironmentSimulationandPollutionControl,SchoolofEnvironment,TsinghuaUniversity,Beijing100084,ChinahighlightsCompositeanammoxreactorcombinedgranulesandbiofilminonesingleSBR.Performanceofhigh-loadinganammoxreactorunderfluctuations.Thecompositereactorpresentedsignificantrecoverypotential.Anammoxgranulationfromflocculentsludgedirectlyduringrecoveryoperation.Thecompositereactorachievednitrogenremovalrateof18.01kgNm3d1.articleinfoArticlehistory:Received14May2014Receivedinrevisedform23August2014Accepted26August2014Availableonline3September2014Keywords:AnaerobicammoniaoxidationCompositesequencingbatchreactorSubstratesinhibitionRecoverypotentialabstractAcompositereactorcombinedwithgranuleandbiofilminonesingleSBRwasdevelopedforhigh-rateanammoxoperation.Lowactivityflocculentinoculumwasusedasseedsludgeandthenitrogenloadingratereached10.62kgNm3d1after93days’operation.Subsequently,theperformanceofhigh-loadinganammoxreactorunderfluctuationconditionwasinvestigated.Duetotheextremelyshorthydraulicretentiontimeandhigh-strengthsubstrates,thereactorpresenteddramaticsubstratesaccumulationwhichresultedinsevereinhibitionsubsequently.Nevertheless,thecompositereactorpresentedsignif-icantrecoverypotentialevenafterbiomasshydrolysiscausedbyinhibition,mainlyduetotheprotectionandpromotionsuppliedbybiofilm.Besides,granulesweregraduallyformedandaccumulatedfromtheflocculentsludgedirectlyduringtherecoveryoperation,furtherelevatingthereactorperformance.Thenitrogenloadingrateandcorrespondingnitrogenremovalrateachieved20.30and18.01kgNm3d1withtotalnitrogenintheinfluentof1500mg/lfinally.2014ElsevierLtd.Allrightsreserved.1.IntroductionInrecentyears,seriouseutrophicationresultedfromthedis-chargeofexcessivenitrogenwiththeacceleratingindustrializationandurbanization,hasbeenespeciallyconcernedinwaterenviron-mentalprotection.Theconventionaltechnologyfornitrogenremoval,nitrificationanddenitrification,requiredplentyofenergytocreateaerobicconditionandorganiccompoundsfornitratereduction.Thisapproachwouldbeespeciallycostlyanddifficultfortreatingwastewaterwithhighconcentrationofammoniawhilesmallamountofcarboncompounds.Forthat,anaerobicammoniaoxidation(anammox)hasbeenconsideredasapromisingalternativetothetraditionalprocessforitsenergy-efficientandcost-saving(Kuenen,2008;Furukawaetal.,2009).Intheanammoxreaction,ammoniaispartiallyoxidizedtonitritefirstly,thentheanammoxwouldcombinetheformednitriteandammoniatodinitrogengaswithasmallamountofnitratepro-duction(vandeGraafetal.,1997).Duetothecost-savinginoxy-genandorganicsconsumption,theanammox-basedtechnologyhasbeenappliedintofull-scalewithmorethan100installationsaroundtheworld(Lackneretal.,2014).Inpreviousresearches,shorthydraulicretentiontime(HRT)ratherthanhigh-strengthinfluentwaspreferredforhigh-loadinganammoxoperation.Additionally,strictoperationconditionswerealsorequiredtomaintainthestabilityofreactor(Tangetal.,2011;Tsushimaetal.,2007).However,inpracticalapplication,therawwastewatertreatedbyanammoxprocessmostlycontainedhigh-strengthnitrogencompoundswithtotalnitrogenconcentrationabove1000mgN/l.Besides,thereactorfrequentlymetoperationfluctuations(e.g.shockload,outofcontrolintemperature)whichwouldcausereactorinhibitionconsequentlyandthissituationmightbeespeciallysevereunderhigh-loadingcondition(Lackner2014ElsevierLtd.Allrightsreserved.⇑Correspondingauthor.Tel.:[phone];fax:[phone].E-mailaddress:[e-mail](J.Zuo).BioresourceTechnology172(2014)50–57ContentslistsavailableatScienceDirectBioresourceTechnologyjournalhomepage:).Forthesereasons,thecapacitytotreathigh-strengthinfluentstablyandtherecoverypotentialafterinhibitionshouldbeespeciallyconcernedforthehigh-loadinganammoxoperation.Previousresearcheshavefocusedondifferentreactorconfigura-tionsandsludgeforms,andfurtherrevealedtherespectiveadvan-tagesofdifferentreactors.Amongthem,granuleswereconsideredasthealternativeforhigh-loadinganammoxoperationduetotheirhighspecificanammoxactivityandthediameterofgranulesshouldbemaintainedwithinrelativelysmallrangeincaseofdis-integrationandfloatation(Luetal.,2012).This,however,reducedtheresistanceforextremeadverseconditionaccordingly(Anetal.,2013).Bycontrast,thebiofilmwasrecognizedforitsexcellentcapacityforshockresistanceandrecoverypotential(Ren-Cunetal.,2012),whilepoorperformanceinmasstransferanddetach-ment.Forthesereasons,acompositereactorcombinedtheseadvantageswouldbeapromisingalternativeforhigh-loadinganammoxoperationandmanagethepotentialfluctuationswellinpracticalapplication.Inthisstudy,weestablishedacompositeSBRcombinedthegranulesandbiofilminonesinglereactorforanammoxoperationandelevatedthenitrogenloadingrate(NLR)torelativelyhighlevel.Underthiscircumstance,theoutofcontrolintemperaturewassimulatedtoinvestigatetheperformanceofhigh-loadinganammoxreactorunder