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Polychlorinated

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PolychlorinatedPolych

    Polychlorinated

    1296Cheneta1./JZhefiangUnivSciA20089(~:1296-1303 ;JournalofZhejiangUniversitySCIENCEA

    ;ISSN1673-565XP

t1:ISSN1862-1775(Online)

    ;wwwzju.educn/jzus;wwwspringedink.com

    ;E-mail:jzus@zjuedu.cn

    ;P0lychl0rinateddibenzo-p-dioxinsanddibenzofuransinfluegas ;emissionsfrom~”palsolidwasteincinerators.ChinaemlSSlonslrommuniciPalso1iwasteinClneratorsin111na..

    ;TongCHENt

    ;,

    dongLI,ShengyongLU,HuifenDAI,Kef;YuelingGU,JianhuaYAN,Xiao

    aCEN

    ;(IStateKeyLaboratoryofCleanEnergyUtilization,ZhejiangUniversity,Hangzhou310027,China)

    ;rSchoolofMedicine,Zh~iangUniversity,Hangzhou31005&China) ;Email:chentong@cmee.zju.edu.cn

    ;ReceivedDec.24,2007;revisionacceptedJune10,2008

    ;Abstract:Polvchlorinateddibenzo-pdioxinsandfurans(PCDD/Fs)emissionsinfluegasfromtwotypesofmunicipalsolid

    ;wasteincinerators(MSWIs)mostcommonlyusedinChinawereinvestigatedinthisstudy.Theselectedincineratorsincludetwo

    ;grate.typeMSWIs:MSWIA(350t/d)andMSWIB(150t/d),andtwofluidizedbedMS

    C(400t/d)andMSWID wIs:MSwI

    ;(400t/d).whichareallequippedwithsemidrylimescrubberandbagfilterexceptMSWI

    Dequippedwithcycloneandwet

    ;scrubberfwS,asairpollutantcontroldevice(APCD).Resuitsindicatedthattheemissionconcentrationandtheinternationaltoxic

    ;equivalentsfI-TEQs1ofthePCDD/Fsfromthestackswereintherangeof1.2l0

    l0.273ng/Nmand0.0l9-0.20lngI-TEQ/Nm~,

    ;respectively.TheyweregreatlylowerthantheemissionregulationstandardofPCDD/FsinChina(1.0ngI-TEQ/Nm).However,

    ;onlythePCDD/FsemissionlevelfromMSWI.Cwasbelow0.1n2I-TEQ/Nm.Althoughthehomologueprofilesweredistinct,

    ;thecontributionsofthe2,3,7,8

    subsitutedcongenerstothetotalI-TEQweresimilaramongalltheinvestigatedMSWIs.Two ;major2,3,7,8.substitutedcongeners,2,3,4,7,8PeCDFand1,2,3,7,8

    PeCDD,accountfor47%and9%(averagevalues)ofthetotal

    ;ITEOvalues,respectively.ThecorrelationbetweenPCDD/Fslevelsandcompositionoffluegaswasalsodiscussed.

    ;Keywords:Polychlorinateddibenzo-pdioxinsanddibenzofurans(PCDD/Fs),Munici

    palsolidwasteincinerator(MSWI),Grate,

    ;Fluidizedbed

    ;doi:10.1631/jzus.A0720144Documentcode:ACLCnumber:X5;X7 ;INTR0DUCT10N

    ;Wichtherapiddevelopmentofeconomyand

    ;greatimprovementoflivingstandardsinChinaa

    ;largeamountofmunicipalsolidwaste(MSW)is ;generated.whichreachedtoaboutl36.38million ;tonsin2002andkeepsgoingupatarateof8l0% ;peryear(Lieta1.,2004;Zhueta1.,2005).Fordis

    ;posingtheseMSW,threeapproaches,i.e.,landfill, ;compostandincinerationareappliedinChina.Among ;them.thoughlandfillisthedominantone,which ;accountsformorethan80%oftheMSWdisposal(Li

    scaleMSWincin ;efaL2004)theamountoflarge

    ;erator(MSWI)plantsisgrowing,especiallyinde

    ;ProjectsupposedbytheNaturalScienceFoundationofZhejiang ;Province(NoX206955),ZhejiangMedicalandHealthResearch ;Fund(No.2007A047)andtheEducationBureauofZh~iangProv- ;ince(No.N2008018l1,China

    ;velopedcitiesanditstotalcapacityhadbeenl3l55t ;wasteperdaybyJuly2002(Zhueta1.,2005)because ;ofitsadvantagesincludingsignificantvolumereduc

    ,90%),massreduction(70%),toxicityreduc ;tion

    ;tion,andenergyrecovery(Yaneta1.,2006). ;In1988.thefirstMSWI,aMartingrateimported ;fromMitsubishiCo.,Japan,wasbuiltinShenzhen, ;China.Sincethen.moreMSWIplantshavebeen ;constructedinBeijing,Shanghai,Guangzhouand ;otherbigcities.Uptonow,morethan140MSWI ;plantsareinoperationorunderconstruction(Bieet ;a1.,2007).Threeincinerationtechnologies,i.e.,grate, ;fluidizedbedandrotarykiIn,arenowusedinChina, ;andthegrateandfluidizedbedtypeboilerscontrib

    ;utedmorethan80%ofthetotalincinerators. ;AlthoughMSWIhasmanyadvantages.many

    ;pollutants,suchasHC1,heavymetals,especially ;polychlorinateddibenzo-pdioxinsanddibenzofurans

    ;

    ;Cheneta1./JZhejiangUnivSciA20089f9J:1296-1303 ;(PCDD/Fs,areemittedduringtheincinerationproc

    ;ess.ApreliminaryinvestigationonPCDD/Fsemis

    ;sionfromfluegasofover15typicalincineration ;facilitieshasshownthathalfofthemexceeded1.0 ;internationaltoxicequivalents(I—TEQs)ng/Nm”at

    ;l1%(v/v)O2,thestandardofPCDD/Fsemission ;regulationinChina(TianandOuyang,2003).Inthis ;study,twogratetypeincineratorsandtwofluidized ;bedincinerators(FBIs)wereinvestigatedfor ;PCDD/Fsemission.Thestudyaimedtodeterminethe

    ;characteristicOfPCDD/FSdistributionprofilesin ;differenttypesOfMSWIsinChina.Therelationship ;betweenPCDD/Fslevelsandcompositionsofflue ;gaswasdiscussed.Furthermore,thesuggestionson ;thecontroltechnologyOfPCDD/Fsincommer

    scaleMSWIplantswerepresented. ;cial

    ;EXPEIUMENTS

    ;Sampling

    ;Table1brieflyliststhespecoftheinvestigated ;MSWI.MSWIA,MSWIBandMSWICareall

    ;equippedwithsemidrylimescrubberandbagfilter

    ;1297

    ;whileMSWIDiSequippedwithcycloneandwet

    ;scrubberfwS1asairpollutantcontroldevice(APCD) ;AllsamplingpointsarelocateddownstreamtoAPCD ;SchematicOfPCDD/Fssamplingsystemisshownin ;Fig.1.ThissamplingsystemwasbasedonUSEPA ;Method0023A(1996).SamplingVOlumeis印一

    ;proximately24N.Allsamplingswererepeated

    ;once.ThePCDD/Fssurrogatestandardswereadded ;tOtheXAD2resinforcheckingthePCDD/Fssam

    ;piingefficiency.Aftereachsampling,thesystemwas ;rinsedwithacetoneandtoluene,respectively,andthe ;rinsewassavedinbrownglassbottle.Filterand ;XAD2resinalsostoredandmaintainedindarkbe

    ;low4.Confielduntiltransferredtothelaboratory. ;PCDD/Fsanalysis

    ;PretreatmentofPCDD/Fsinthecollectedflue ;gaswasconductedaccordingtotheUSEPAMethOd ;l6l3Bfl994).Thesamplewasspikedwithknown ;amountsofl3Clabelledinternalstandards.then ;Soxhletextractedwithtoluenefor24h.Afterex~ac

    ;tionthesamplewasmacroconcentratedbyrotary

    ;evaporatorto1-2ml,andthenthesampleextracts ;wereexchangedintohexane.Samplecleanup ;Table1SpecoftheinvestigatedMSWI

    ;Note:activatedcarbonwasusedtoremovePCDD/FsinthefluegasproducedfromMSWI?-

    AandMSWI?-B

    ;Filter

    ;Fig.1SchematicofsystemforPCDD/Fssamplingfromfluegas ;1e

    ;

    ;1298Cheneta1./JZhejiangUnivSciA20089(9):1296-1303 ;proceduresinvolvedamultisilicagelcolumnanda

    ;basicaluminacolumn.TheelutewascOncentrated ;againandblownwithnitrogentoapproximately20u1 ;Beforeanalysisthe”C—labelledinjectionstandards ;wereaddedtothesampleforcalculatingtherecovery ;of”C—labelledinternalstandards.Allsolventswere ;purchasedfromMallinckrodtBakerInc.,USAand ;werepesticideresidueanalysisgrade.Theanalysis ;wasperformedbyHRGC/HRMSona6890Series ;gaschromatograph(Agilent,USA)andcoupledtoa ;JMS800Dmassspectrometer(JE0L.Japan).A ;DB5msfusedsilicacapillarycolumn(60mx0.25 ;mminsidediameter.0.25gmfilmthickness)was ;used.Thetemperatureprogramwasasfollows:150 ;.C.heldforlmin;increasedatarateof25.C/minto ;l90.C:thenincreasedatarateof3.C/minto280.C. ;heldfor20min.Thecarriergaswasheliumatacon

    ;stantflowrateof1.2ml/min.Themassspectrometer ;fMS)wasoperatedataresolutionofl0000under ;positiveelectronionizationfEI1condition(38eV ;electronenergy).Oneglofsamplewasinjectedusing

    samplerinsplitlessmode.ThePCDD/Fs ;anauto

    ;werequantifiedusingamolecularionfM),anM+2 ;ionoranM+4ion.TheITEQswascalculatedusing

    ;theinternationaltoxicequivalencefactorrITEF)

    ;(NATO/CCMS.1988).

    ;RESUISANDDISCUSSION

    ;PCDD/FscOncentratiOnintheflnegas

    ;PCDD/Fsconcentrationinthefluegaswas ;showninTable2.TheI.TEQvalueswereintherange ;of0.019-0.201ngITEQ/Nm.whichwerealllower

    ;thanthestandardlimitofChinar1.0ngITEQ/Nme).

    ;In2001.theStateEnvironmentalProtectionAdmini

    ;stration(SEPA)ofChinainvestigatedthepollutants ;includingPCDD/Fsemissionfroml5MSWIs.The ;investigatedresultsshowedhalfdataofPCDD/Fs ;concentrationinthefluegasexceed1.0ng ;ITEQ/Nm.indicatingthattheemissionlevelsof ;PCDD/FsfromtheMSWIshavebeenreducedover ;thepastfewyears.However,halfdataoftheemission ;resultswereslightlyhigherthanthedevelopedcoun

    ;triesemissionlimitof0.1ngITEQ/Nm.Sothe

    ;controltechnologiesforPCDD/Fsneedtobeim. ;provediftheemissionlimitwasloweredto0.1ng ;ITEQ/Nm.

null

    ;thefluegasfromFBIsandgratefiredincinerators ;weredifferent,the2,3,7,8.substitutedcongenersdis. ;tributionpattemsweresimilarforallMSWIs(Fig.31. ;Thecomparisonbetweenthisdataandothersob

    ;tainedfromHarbinofChina,KoreaandJapanwas ;showninFig.4.Theverysimilardistributionof ;2,3,7.8.substitutedcongenerswasfoundinChinese ;MSWI.Forexample,l,2,3,4,6,7.8.hepta.chlorinated ;dibenzo-p.dioxin(HpCDD1andocta.chlorinated ;dibenzo-p.dioxin(OCDD)werethemajorcongeners ;forPCDDs.2,3,4,7,8.penta.chlorinateddibenzofuran ;(PeCDF)andl,2,3,4,6,7,8-hepta.chlorinateddiben. ;zofuran(HpCDF)werethepredominantcongeners ;forPCDFs.However.therewasdifferentdistribution ;forPCDD/FsemissionfromMSWIinKoreaand

    ;Japan.2,3,4,6,7,8.hexa.chlorinateddibenzofuran ;(HxCDF)andl,2,3,4,6,7,8-HpCDFamountedto ;morethan54%oftotalPCDFsforMSWIinKorea. ;1,2,3,4,6,7,8.HpC!DFandocta.chlorinateddibenzo. ;furanfOCDF1werethemajorcongenersforPCDFs ;OfMSWIinJapan.

    ;2,3,4,7,8.PeCDFandl,2,3,7,8penta.chlorin. ;ateddibenzo-p.dioxin(PeCDD)weretwomajor ;2,3,7,8.substitutedcongeners,andtheircontributions ;wereupto47%and9%(averagevalues1ofthetotal ;TEQvalues,respectively,duetotheirhightoxicity ;(I.TEFvalueisall0.5.KatoandUrano(2001)also ;foundthat2,3,4,7,8.PeCDFandl,2,3,7,8.PeCDD ;contributedtoabout49%oftheI.TEQvalues.The ;contributionOf2,3,4,7,8.PeCDFwasstable,though ;thecontributionOfl,2,3,7,8.PeCDDfluctuated. ;Severalresearchershavereportedalinearcorrelation ;betweenthe2,3,4,7,8.PeCDFconcentrationandTEO ;values(Fiedlereta1.,2000;KatoandUrano,2001: ;Iinoeta1.,2003).Thepositivecorrelationwasob. ;tainedfromthispaper(Fig.5.whichwasdifferent ;fromtheresultsofKatoandUrano(200l1.Intheir ;study,thecorrelationbeeenthe2,3,4,7,8.PeCDF ;concentrationandI.TEQvaluescouldbedescribed ;bythefollowingEq.fl1.Thedifrerencecoefficient ;maybeattributedtodifferentMSWcomposition, ;furnacetype,etc.Inthisstudy,thecorrelationcould ;bedescribedbyEq.f21.

    ;[I-TE畲畲冬冬冬至g堇堇晕

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    ;004

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    ;

    ;80.01

    ;O

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    ;g

    ;PCDD/Fscongeners

    ;Fig.3ProfilesofPCDD/Fscongenersinthefluegasfrom(a)MSWI-A,(b)MSWI-B,(c)MS

    WI-Cand(d)MSWI-D

    ;CorrelationPCDD|Fslevelswiththecomposition ;Offluegas

    ;Itiswellknownthatvariousfactorscanafrect ;PCDD/Fsemission.Compositionoffluegasisoneof ;thefactors.1’able3showsthecompositionoffluegas

    ;andthePCDD/FslevelsinMSWI.AandMSWI.C. ;CO,O2,waterandothercompoundswerecontinu. ;ouslymeasuredforabout30minbyusingafluegas ;analyzerduringthePCDD/Fssamplingprocess.A1- ;thoughthereareonly4datasetsavailableinTcable3. ;thesimilarresultswerefound.

    ;C0value,oneoftheparameterstoiudgethe ;combustionquality,hasbeenusedasaparameterto ;evaluatePCDD/Fsemissionsinseveralstudies.Sa. ;kuraieta1.(2000)foundthatnewFBIswithwell ;controlledcombustionemittedlessPCDD/Fsinflue ;gasandflyash,whileoldFBIswithhighCOcon. ;centrationhadhigherPCDD/Fsemission.However, ;otherstudiesindicatednosignificantcorrelation ;betweenCOvaluesandthePCDD/Fslevelsin ;MSWIsorpilotincinerators(WeberandHagenmaier. ;1999;Webereta1..2002).Inthepresentstudy,C0 ;valuesshowednopositivecorrelationwithPCDD/Fs ;levels.InMSWI.A.theCOvalueswerelowerthan ;thedetectlimitofthefluegasanalyzer.Thecasewas

    ;onthecontraryforMSWI.C.ButthePCDD/Fslevels ;intheMSWI.AwerehigherthanthoseofMSWI.C. ;O2contentalsoaffectedthePCDD/Fsformation. ;ChangandHuang(2000)investigatedtheeffectofO2 ;contentonthePCDD/FsformationinMSWflyash. ;TheyfoundthatthePCDD/Fsformationincreased ;withtheincreaseofO,contentinelectrostaticpre. ;cipitator(ESP)flyash.Wealsofoundapositivecor. ;relationbetweenPCDD/Fslevels(TEQvalue)andO2 ;contentasshowninTable3.InChina.thePCDD/Fs ;emissionstandardforMSWIswasbasedonstandard ;drygascorrectedtol1%(v/v)O2.IftheO2content ;washigherthanl1%rv/v),thePCDD/Fslevelswould ;Z岛一岛0l1luo0?00u

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    ;Chenetal/JZhejiangUnivSciA20089f9J:12961303

    ;behigherthanthedetectedvalue.Itwasreportedthat ;PCDD/FsemissionwasminimalwhentheO2content ;wasbetween6%9%(V/V)(Yaneta1.,2006).SoO2

    ;contentmightbeaparameterforPCDD/Fscontrol

    ;ling.

    ;AsMSWIfluegascontainswater,experiments ;wereperformedinseveralstudiestocomparethe ;formationofPCDD/Fswithandwithoutwaterinthe ;PCDD~scongeners

    ;Fig.4Comparisonbetweenthisdataandotherdata ;fromtheBterature

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    ;2,3,4,7,8PeCDFconcentration(ng/Nm3) ;Fig.5Relationshipbetween2,3,4,7,8PeCDFeoneentra-

    ;tionandTEQvaluesinMSWI-AtoMSWI-D

    ;1301

    ;gasflow(AddinkandOlie,1995).Stieglitzeta1.(1990) ;reportedthatPCDD/Fsformationlevelsfromcar- ;bon/flyashat300.Cwithwaterincreasedcompared ;tothosewithoutwater.However,JayandStieglitz ;r1991)foundadecreaseofthetotalPCDD/Fsamounts ;formedinthepresenceofwaterwithcharcoal/ ;MgSiO2/CuCl2inairat300.C.Lieta1.(2006)inves

    ;tigatedtheef.fectOfwatervaDoroncatalyzeddenovo ;formationofPCDD/Fs.Theirresultsindicatedthat ;watervaDorcouldpromotethePCDD/Fsformation. ;Wealsofoundapositivecorrelationbetweenwater ;andTE0valuesofPCDD/FsasshowninTable3. ;Ithasbeenreportedthatcofiringcoalwith

    ;MSWcouldreducePCDD/Fsemissionsduetothe ;increasedfluegasSO2concentration(Ryaneta1., ;2006).IntroducingSO2intothefurnacesectionofa ;11scaleinc?

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