外文翻译--两段式厌氧固定床反应器处理含愈创木酚废水的研究 英文版.pdf

第33卷第4期2007年12月延边大学学报(自然科学版)JournalofYanbianUniversity(NaturalScience)Vol.33No.4Dec.2007收稿日期:2007208222基金项目:教育部留学回国人员科研启动基金资助项目(20052383号)作者简介:尹成日(1963),男(朝鲜族),博士,教授,研究方向为环境污染物的生物处理.文章编号:100424353(2007)0420259205TreatmentofWastewaterContainingChloroguaiacolsUsingTwo2stageAnaerobicFixedBedReactorYinCheng2ri1,GAOZai2yuan2(1.KeyLaboratoryofOrganismFunctionalFactorsoftheChangbaiMountain,MinistryofEducation,YanbianUniversity；2.LibraryofYanbianUniversity:YanjiJilin133002,China)Abstract:Anaerobictreatmentofwastewatercontainingchloroguaiacolswasstudiedwithfocusontheremovalofchlorinatedguaiacols.Experimentswerecarriedoutusingalaboratory2scaleanaerobicfixedbedreactoroperatedatdifferenthydraulicretentiontimes(HRTs).TheprocessefficientlyremovedfourtypesofchlorinatedguaiacolswhentheHRTwas24h.Inthiscondition,allchlorinatedguaiacolswerealmostcompletelyremoved.Themicrobialcommunitystructureinthereactorwasnotchangedsignificantlyduringoperatingperiod.Keywords:anaerobictreatment；chloroguaiacols；fixedbedreactorCLCnumber:X703.1Documentcode:A1IntroductionTraditionally,theconcernoverdischargesfromthepulpandpaperindustryhasbeenfocusedontheriskoffiberdepositionsandoxygendeficiency.Inrecentyears,however,interesthasshiftedtowardstheenvironmentalimpactofchlorinatedorganiccompoundsintheeffluents,resultingfrompulpbleachingwithchlorine2containingchemicals.Manychlorinatedorganiccompoundsoflowmolecu2larmassareknowntobetoxic,bioaccumulable,mutagenicandpersistentanditisthereforeimportanttoavoidreleasingsuchcompoundsintotheenvironment.Conventionalaerobicbiologicaltreatmentemployingaeratedlagoonsandactivatedsludgeprocessesiscommonlyusedatpulpandpapermillstoremovebiochemicaloxygendemand(BOD)fromtheefflu2ents.Thesetreatmentmethodsremovealsoasignificantpartofabsorbableorganichalogens(AOX)；theAOXremovalrangingfrom20%to60%hasbeenreported1.However,aerobictreatmentgeneral2lyhasapooreffectonpolychlorinatedcompounds.Underaerobicconditions,chlorinatedguaiacolsandphenolscanbeO2methylatedtothecorrespondinganisolesandveratroles,whicharemoreresistanttobiodegradationandhavehigherpotentialforbioaccumulationinfish2.Andmanyvolatilechloro2organiccompounds,suchaschloroform,arelikelytoberemovedfromtheeffluentbystrippingratherthanbybiodegradation,resultinginanuncontrolledemissionofthesecompoundsintotheenvironment.Studiesonanaerobictreatmentofbleachingplanteffluenthaveshownthistreatmenttohaveseveraladvantagesascomparedtoaerobictreatment:polychlorinatedchlorophenolicsareremovedsignificantly,ahigherAOXremovalisachievedandthephytotoxicchlorateeliminated.Furthermore,anaerobictreatmentshouldbeasignificantlymorecost2efficientwaythanaerobictreatmenttoremoveBOD,providingthatanefficientconversionoforganicmatterintobiogascanbemaintainedintheprocess.Thusfar,mostinvestigationshavebeenfocusedontheremovalofunspecifiedAOX.However,thedegradationofspecificcompounds,e.g.chlorinatedguaiacolsintheanaerobictreatmentprocesshasnot©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http:/www.cnki.net延边大学学报(自然科学版)第33卷beensystematicallystudied.Theaimofthepresentstudywastoevaluatethepossibilityofachievingchloroguaiacols(tetrachloroguaiacol:TeCG,4,5,62trichloroguaiacol:4,5,62TriCG,4,52dichloroguaiacol:4,52DCG,and42chloroguaiacol:42CG)removalinthetwo2stageanaerobicfixedbedreactor.2Materialsandmethods2.1SyntheticwastewatercontainingchloroguaiacolsSyntheticwastewatercontainedmixturesof42CG,4,52DCG,4,5,62TriCG,andTeCG.Thewastewaterwassuppliedwith0.2gyeastextract,0.1gNH4Cl,27mgKH2PO4,25mgMgSO4·7H2O,11.3mgCaCl2,2.8mgFeSO4·H2O,5.5mgMnCl2·H2O,0.68mgZnCl2,1.2mgCoCl2·6H2O,1.2mgNiSO4·4H2O,0.025mgNa2MoO4·2H2Oand0.026mgNa2SeO3·5H2Ol-1.Theconcentrationofallfourchloroguaiacolsinthesyntheticwastewaterwas0.05mM.Glucoseaselectrondonorforanaerobicdechlorinationwasused.Thecompoundwasaddedtothesyntheticwastewaterinanamountcorrespondingto1000mgCODl-1.2.2AnaerobicdigestersludgeTheanaerobicdigestersludgehadbeenobtainedfrom3500m3anaerobicdigesterreactor(inopera2tionfor10yearsatthehydraulicretentiontimeof25days)ofTaejonsewagetreatmentplantinKorea.Thesludgewasstoredat4ingas2tightplasticcontainerforamaximumperiodoffivemonths.Intheassay,17.4gvolatilesuspendedsolidl-1(ratioofVSStoSSwas0.561)oftheanaerobicsludgewasused.2.3ReactordesignandoperationTwoidenticalreactors(R1andR2),designedasanaerobicfixedbedreactorandconstructedofpolyvinylchloride(PVC),wereusedinthestudy.Eachreactorwas7.0cmindiameter,andheightfromtheinlettotheoutletwas48.0cm.Thisprovidedaneffectivebedvolumeof1.4L.Atthetimeofexperimentation,thesludgedepthwasapproximately34.0cm.Thereactorswereoperatedathydraulicretentiontimes(HRT),basedonthereactorliquidvolume,of12,and24hours,placedinatemperaturecontrolledroomat30.ThepHofthebleachingplanteffluentwasmeasuredandadjustedto7.5with2MH2SO4.Thereactorswerefilledwithceramicspheres(diameter5mm)assupportmediumforanaerobicdigestersludge.Wastewaterwasfedtothesystembyaperistalticpump.Initially,thereactorswereinoculatedwithanaerobicdigestersludge,andthenstartedupandoperatedforaweekonthesyntheticwastewateratalowfeedrate(HRT=48h)toallowthesludgetoacclimatizetothechlorinatedguaiacols.2.4NucleicacidextractionandPCRamplificationof16SrDNADNAwasextractedwithhotsodiumdodecyl2sulfate2phenolandwaspurifiedbyusingphenol2chloroform2isoamylalcohol(25241,V/V/V),followedbyethanolprecipitation；about100mg(freshweight)ofsludgeandtheprotocolofOelm¨ulleretal.3wereused.Fragmentsofthe16SribosomalDNA(rDNA)suitablefordenaturinggradientgelelectrophoresis(DGGE)analysiswereobtainedbyusingtwodifferentprimercombinationsfordifferentphylogeneticlineages(Table1)；onecombinationwasusedformembersofthedomainBacteria4,theothercombinationwasusedformembersofthedomainArchaea5.ThelengthsofthePCRproductswere585and624bp,respectively.Recently,researchershaveshownthatthebacterialprimercombinationconsistingofprimers341Fand907Rusedhereprovidesthemostreliableresults6.ThePCRconditionsusedforthebacterialprimersetshavebeendescribedpreviouslybyMuyzeretal.4Toamplifythearchaealgenes,weusedatouchdownprotocolfor20cycleswithtemperaturesrangingfrom71to61；theannealingtemperaturewasreduced1everytwocycles.Thisprocedurewasfollowedby15additionalcyclesatanannealingtemperatureof61.Exceptforthe062©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http:/www.cnki.net第4期尹成日,等:两段式固定床厌氧反应器处理含愈创木酚废水的研究initialdenaturationstep(94,5min),denaturationandannealingphasestepswere1minlong,whilemostofthepolymerizationphasestepswere3minlong(theonlyexceptionwasthefinalcycle,whichwas10minlong).Table1Sequences,targetsites,andspecificitiesoftheprimersusedinthisstudyPrimeraTargetsitebSequence(5to3)Specificity341F2GCc341357CCTACGGGAGGCAGCAGMostBacteria907R907926CCGTCAATTCCTTTGAGTTTMostknownorganismsARC344F2GC344363ACGGGGYGCAGCAGGCGCGAMostArchaeaARC915R915934GTGCTCCCCCGCCAATTCCTMostArchaeaaF(forward)andR(reverse)indicatetheorientationoftheprimersinrelationtotherRNAsequences.bEscherichiacolinumberingofBrosiusetal.7.cGCisa402nucleotideGC2richsequenceattachedtothe59endoftheprimerasdescribedbyMuyzeretal.4.TheGCsequenceis52CGCCCGCCGCGCCCCGCGCCCGTCCCGCCGCCCCCGCCCG23.2.5DGGEanalysisofPCRproductsDGGEwasperformedfor4.0hataconstantvoltageof200V.About600ngofPCRproductwasdepositedineachwell.Afterelectrophoresis,thegelswerestainedwithGelStarNucleicAcidStain(Takara,Japan)andphotographedwithUVtransillumination(wavelength,314nm)withaPolaroidcamera.2.6AnalysisofchloroguaiacolsandVSSThehexaneextractsofacetylatedsamplesweretheninjectedintothegaschromatography,forchlorinatedguaiacolsanalysis.AllgaschromatographyexperimentswereperformedwithaHewlettPackardmodel5890seriesinstrumentequippedwithaflameionizationdetector.Afusedsilicacapillarycolumn(30m×0.53mm×2.65m)wasused.Theinitialoventemperaturewasheldat100for1minandthenincreasedatarateof6/mintoafinaltemperatureof260.Injectionport,anddetectorwereheldat275.Heliumwasusedasacarriergasataflowrateof30mL/min.VSSweredeterminedaccordingtothestandardmethods8.2.7ChemicalsChlorinatedguaiacolsthatareusuallypresentinratherhighconcentrationsinbleachingplanteffluentwereanalyzedandusedasindicatorsoftreatmenteffect.Thechlorinatedguaiacols(purity:tetrachlo2roguaiacol99+,4,5,62trichloroguaiacol99+,4,52dichloroguaiacol99+,42chloroguaiacol90%95%)werepurchasedfromHelixBiotech.Corp.(Columbia,NewWestminster,BC,Canada).Otherchemicalswerereagentgradeandwerepurchasedfromtheusualcommercialsources.Nitrogengasof99.999%(V/V)puritywasusedwithoutanytreatment.3ResultsanddiscussionHydraulicretentiontime(HRT)isonethemostimportantfactorsaffectingthebioreactorefficiency.ToinvestigatethebiodegradationefficiencyofchlorinatedguaiacolsinresponsetothevarianceofHRT,syntheticwastewatercontainingchloroguaiacolswascontinuouslyfedintothetwo2stageanaerobicfixedbedreactor,varyingtheHRTfrom24to12hours.DuringtheoperationalperiodthepHremainedcon2stant,between7.0and8.0.AsshowninFig.1andFig.2,the4,5,62TriCGand4,52DCGwereremovedmorethan90%,butTeCGand42CGshowedunstableremovalinR1.TheremovalratesofTeCGand42CGwere75%85%.However,allchlorinatedguaiacolswerealmostcompletelyremovedinR2.After2weeks,HRTwasdecreasedfrom24(totalloadingrateoffourtypesofchlorinatedguaiacolswas42.1g/(m3·d)to12hours.Duringthisperiod,although4,5,62TriCGand4,52DCGwerealsoremovedcompletely,completeremovalofTeCGcouldnotbeattained.However,afterincreasingHRTto24hoursagain,removal162©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http:/www.cnki.net延边大学学报(自然科学版)第33卷efficienciesofchlorinatedguaiacolswerequicklyrecovered.Theremovalefficienciesofchlorinatedguaiacolsinthetwo2stageanaerobicfixedbedsystemwereinthefollowingorder:4,52DCG>4,5,62TriCG>42CG>TeCG.Thisisinaccordancewiththeresultobtainedfrombatchtest.:Influentconcentration:concentrationofR1effluent":concentrationofR2effluentFig.1RemovalratesofTeCG(A)and4,5,62TriCG(B)Fig.2Removalratesof4,52DCG(A)and42CG(B)intwo2stageanaerobicfixedbedreactorintwo2stageanaerobicfixedbedreactorFromtheseexperimentsitispossibletoconcludethattheanaerobicfixedbedreactorisanefficienttreatmentmethodforwastewatercontainingchloroguaiacols.However,finaleffluentshouldundergoanadditionaltreatmente.g.anaerobicprocesstocompletelyeliminatetheresidualfractionofchlorinatedguaiacols2derivedmetabolites.H¨aggblomandSalkinoja2Salonen9treatedkraft2bleachingwastewaterinananaerobicfluidizedbedandobtainedbetween16%61%removalofchlorinatedguaiacols(TeCG,3,4,52TriCG,4,5,62TriCG,and4,52DCG).Parkeretal.10alsostudiedtheremovalofchlorinatedphenolicsfromkraftmillbleach()freshsludge,()R1sludge,()R2sludgeFig.3DGGEpatternsof16SrDNAfrag2mentsfromfreshsludge,R1andR2sludgeinthetwo2stageanaerobicfixedbedreactor(R1andR2)treatingchloroguaiacols2containingwastewaterplanteffluentsinanadaptedanaerobicsludgeblanketreactor.Inthepresenceoftheco2substratesmethanolandethanol,toxicityremovalwasabout93%andabout65%withouttheco2substrates.Inthesamestudy,42chloroguaiacol,4,52dichloroguaiacol,and4,5,62trichloroguaiacolwerealmostcompletelyremovedinthepresenceofco2substrates(>95%).Microbialcommunitystructureinsludgesampledfromtwo2stageanaerobicfixedbedreactortreatingchloroguaiacols2containingwastewaterwasassessedbyPCR2DGGEanalysisof16SrDNAfragments.PCR2DGGEanalysisshoweddidnotsignificantdifferencesinArchaeamicrobialcommunitystructurebetweenthesludgestudied(Fig.3).Anadditionalband3fromR2sludgecomparedtofreshsludgewasfoundinEubacteria262©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http:/www.cnki.net