UASB生物膜反应器厌氧氨氧化反应的启动研究英文周少奇

№.4　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　Aug.200650　　　　　　JOURNALOFSHAANXIUNIVERSITYOFSCIENCE&TECHNOLOGY　　　　　Vol.24*　:1000-5811(2006)04-0050-05START-UPANAEROBICAMMONIUMOXIDATION(ANAMMOX)PROCESSINUASB-BIOFILMREACTORZHOUShao-qi,YAOJun-qin(CollegeofEnvironmentalScienceandEngineering,SouthChinaUniversityofTechnology,Guangzhou510640,China)Abstract:Thestart-upofANAMMOXprocesswasinvestigatedbyusinga3.2LUASB-bio-filmreactorinoculatedwithactivatedsludgefromalandfillleachatetreatmentsystem.TheUASB-biofilmreactorwasfeedwithartificialwastewatercomposedwithammoniumandni-triteatproperNH+4-N,NO-2-Nratio.TheresultsdemonstratedthatANAMMOXprocesswasachievedsuccessfullywithhighremovalefficienciesofNH+4-N,NO-2-NandTN(99.4%,97.4%and90.0%)after56daysofoperationandacclimation.Theratioofre-movedammonia,nitriteandproducednitratewas1∶1.61∶0.25atthestablestageoftheprocess.TheeffluentpHvaluekeptaround8.3andthealkalinityvariedalittle.Theob-tainedbiofilmwithhighANAMMOXactivitywasbrown.Thegrain-sludgeofbrownandpinkwerefoundatthebottomofthereactor.Keywords:ANAMMOX;UASB-biofilmreactor;landfillleachate;start-upCLCNumber:X703　　　DocumentCode:A0IntroductionANAMMOXhasbeendiscoveredbyMulderA.etalinadenitrifyingfluidizedbed-reactoronday420whenlargequantitiesofammoniumwereobservedtodisappearandnitrateconsumptionsimultane-ouslyelevated[1].Andthenitritehasbeenfoundtobethepreferredelectronacceptorfortheprocess[2].TheelectronicstoichiometricanalysesdemonstratethatANAMMOXprocesshasalotofadvantagescomparedwithtraditionalnitrificationanddenitrificationfornitrogenremoval[3,4].Owningtoremovingammoniumandnitrite,twokindsofpollutionswithoutconsumingorganicsubstance,ANAMMOXprocessisanewandpromisingalternationtotheconventionalmicrobialnitrogenremoval,whichbasedonautotrophicnitrificationandheterotrophicdenitrification.However,ANAMMOXprocessorANA-MMOXbacteriaiswidelyfoundtoexistinoxic/anoxicinterfaceecosystem,suchasdry/wetinterfaceofsoil[5],theanaerobiczoneattheseabottom[6]orcoastalbayatdepthof200m[7].ANAMMOXbacteriahavealsobeendetectedinwastewatertreatmentsystemsbyanumberofinvestigatorsfromdifferentcountries,suchasthosefromNetherlands[8],Germany[9],Switzerland[10],UK[11],Australia[12],andChina[13～17],etc.TheseallimpliesthatANAMMOXprocessmightbeamorewidelyexistingbioprocessinnaturethanpreviouslyassumedandconsidered.Thestart-upandacclimationofANAMMOXprocess*:2006-04-17　:(1965-),,,,,,::(20377013),(020959)4:UASB-isdifficultbecauseANAMMOXischaracterizedbyslowgrowthandinteractionwithotherbacteria.ThedoublingtimeofANAMMOXbacteriainthelaboratoryhasfoundtobe11daysunderoptimalconditionsand2～3weeksonaverage[18].Owingtothislowgrowthrate,enrichmentculturefromsuitableinocu-latesgenerallytakes100～200days[19].However,thepreviouslyreportedsludgeforinoculationtostart-upANAMMOXprocesshavebeenmostlynormalactivatedsludge[13],normalanaerobicgranularsludge[14],riversedimentssludge[14],thicksludgefromwastewatertreatmentplant[15],ormixtureofaer-obicandanaerobicactivatedsludge[14,16].TheresultsindicatedthatANAMMOXmightbestartedupsuccessfullyafter105dayto250daysofacclimationandhighremovalefficienciesofnitriteandammoni-umcouldbeachieved.Thegoalofthisstudywastoinvestigatethestart-upofANAMMOXprocessinanUASB-biofilmcombinedreactorwithactivatedsludgefrombiotreatmentoflandfillleachatesincetherewasnoreportonANAMMOXincaseofinoculationwiththiskindofsludge.1　MaterialsandMethods1.1　ReactorsystemAschematicdiagramoftheexperimentalprocedureisshowninFig.1.AnUASBreactorhasatotalvalidvolumeof3.2liter,providingasettlingzoneof0.92Latthetopandthereactionzoneof2.28L.Thetemperatureofreactionwaskeptat32±1℃byathermostat-waterbath.Theinfluentwaspumpedintothebottomofthereactor.TheinfluentDissolvedOxygen(DO)concentrationwasabout2.7～3.2mgL-1andnoairexhaustingdevicewasmountedbeforethesubstratewaspumpedintothereactor.Fig.1　TheUASB-bioflimreactorsystemforANAM-MOX1.UASBreactor,2.influentpump,3.influenttank,4.thermostat-wa-terbath,5.thermometer,6.off-gas,7.effluent,8.samplepoints1.2　SludgeTheactivatedsludgewastakenfromalandfillleachatewastewatertreatmentplantinJiangmencity,southChina,andwasusedasinoculumsforstartingupANAMMOXprocessintheUASB-biofilmreactor.Thesludgewasredandbrown.Littleminianimalshadbeenseeninthesludgeunderanopticalmicroscope.2.4Lofthemixedliquidsuspendedsludge(MLSS)wasputintoreactor,accountingfor75%ofthereactor.1.3　SyntheticwastewaterTheUASBreactorwasfedwithsyntheticwastewater,themediumcompositionsislistedasfollows:KH2PO40.027gL-1;MgSO4H2O0.300gL-1;CaCl20.136gL-1;NaHCO30.500gL-1.Traceele-mentsolutionⅠ:FeSO45.000gL-1.TraceelementsolutionⅡ:ZnSO47H2O0.430gL-1;CuSO45H2O0.250gL-1;MnCl24H2O0.990gL-1;NiCl26H2O0.190gL-1;CoCl26H2O0.24gL-1;H3BO40.014gL-1.NH4ClandNaNO2wereusedforprovidingthenee-dedNH+4-NandNO-2-N.Therewasnoorganicsubstancein.1.4　AnalyticalmethodsTheconcentrationsofNH+4-N,NO-2-NandNO-3-NweredeterminedbythestandardmethodsofChina[20](EnvironmentalProtectionAgency,2000).ThepHvaluewasdeterminedusingglasselectrodesconnectedtopHS-3Cacidity-meter.TheAlkalinitywasdeterminedbytitration.DOwasmeasuredbyu-singpo