WPC n9+a> .8t̐vSNMͥ v>(^4 JjxqNFDʆ0M칶9uKc*q;}` ._ʴZi ̣]Ų+1ߘN '[QФ H-GOX. '> j|@kϞߦ)r1X?%B?L{(rj#(5|HwHRk=bcwBR\_/:9G+υ[Kbwdl Vt-f{7L6]:\oVs㩒ܹ+c9mijU_92?S(1y!"RKzC5˞a> ݌rco3?t9d mn6w Ŷ*Km/T;NyAA-v$Qфr25X#!U: %+ 0(1w@YU N4  p f@ URNB UN ^ a B* f( * m, fC aE fY a[ [ o a N & 0D i D3( 0D[ [ B  D+ 0K A22222222222222222222222222222222 D3Panasonic DP-30000,  AZ"Arial RegularX($ D (hH  Z 6Times New Roman RegularLevel 1Level 2Level 3Level 4Level 5]t(\3|xcogenerationSCONOx CEMS CFRPMACT CTWG(hH  Z 6Times New Roman Regular46Times New Roman Regular,TABLE B&0 d dUTABLE BTABLE B cogenerationcombustorsSCONOx HAPssiloxaneSiloxanescombustorMMBtuSCONOxTM LLC LAER BACT ppm VOCs ppbTABLE B >e$"Small Circle"),'dxd(3$ !   d'dxd( $ Figure  1  *.-&OLE 2.0 Box <=8C HKKKK,,,,'dxd !  _XbmXXX XbmXXXbm8 bm XXdd8#XbmXX XbmJ#  April3January15,2002 XbmXXXbm L  MEMORANDUMFROM:0 ` SimsRoy L ` (#` (#   0 ` EmissionStandardsDivision 8 ` (#` (#   0 ` CombustionGroup$ ` (#` (# TO:0  0` (#(#DocketA9551 ` (#` (# SUBJECT:0 ` HazardousAirPollutant(HAP)EmissionControlTechnologyforNewStationary   CombustionTurbines ` (#` (# ThepurposeofthismemorandumistosummarizetheHAPemissioncontroltechnologyfornewstationarycombustionturbinesandtoprovideemissionfactorswhichmaybeusedtoestimateHAPemissionsfromcombustionturbines.Twotypesofcontroltechnologiesarediscussedinthismemorandum:oxidationcatalystsystemsandleanpremixcombustion. OxidationCatalystSystems  H Thereareabout200combustionturbinesintheUnitedStatesthathaveinstalledoxidationcatalystsprimarilyforcontrollingcarbonmonoxide(CO)emissionsbutalsoforvolatileorganiccompound(_VOC_)andhydrocarbonemissioncontrol.TheseoxidationcatalystsystemsalsoreduceHAPemissionssuchasformaldehyde,acetaldehyde,andbenzenefromalltypesofcombustionturbines,includingsimplecycle,combinedcycle,cogeneration,andbaselineandpeakingunits.Oxidationcatalystsystemshavebeeninstalled#XbmXX Xbm#only XbmXXXbmondiffusionflamecombustion l turbines.Inadiffusionflamecombustor,thefuelandairareinjectedatthecombustorandaremixedonlybydiffusionpriortoignition.Theperformanceoftheseoxidationcatalystsystemsondiffusionflamecombustionturbinesresultsin90pluspercentcontrolofCOandabout85to95percentcontrolofformaldehyde.SimilaremissionreductionsarealsoachievedonotherHAPpollutants.ThisdeterminationisbasedprimarilyonanevaluationofatechnologycalledSCONOx,whichisacomparabletechnologytoCOoxidationcatalysts.ItemploysapreciousmetalcatalystfortheremovalofCOviacatalyticoxidation,justasaCOoxidationcatalystdoes.AcorrelationwasthereforemadebetweentheefficienciesoftheSCONOxsystemandCOoxidationcatalysts.ThedifferenceisthattheSCONOxsystemusesachemicallymodifiedcatalystsothatthecatalystalsoremoves_NOx_.Thesechemicalmodificationsarenotbelievedtoaffecttheoxidationcatalystperformance.Formoreinformationonthistopic,refertoAttachmentA. h+&*     FormaldehydeisthemostsignificantHAPemittedfromcombustionturbinesandaccountsforaboutthreefourthsoftheHAPemissions.CarbonmonoxideisagoodsurrogateforformaldehydeandotherHAP.Therefore,assuringthattheoxidationcatalystsystemisachieving90pluspercentreductionofCOassuresthatthesamecatalystsystemiseffectiveinreducingformaldehydeandotherHAPemissions.Carbonmonoxideconcentrationscanalsobereadilymonitoredcontinuously,whereasformaldehydeandotherHAParedifficulttomonitorcontinuously.ItmayalsobepossibletoestablishaconcentrationlimitforCOorHAP,butapercentreductionisasoundperformancecheckoftheoxidationcatalystsystem.Oxidationcatalystsystemscanbeusedoncombustionturbineswhichcombustalltypesofgaseousandliquidfuelsexceptforlandfillanddigestergases,whichfoulthecatalystveryquicklybecauseofacompoundcalledsiloxanecontainedinthesefuels.Siloxanesaredifficultandverycostlytoremovefromthesefuels.Therefore,theapplicationofoxidationcatalystsystemstocombustionturbinesthatburnlandfillordigestergasdoesnotappeartobefeasible.Alsotherearenoknowninstallationsofoxidationcatalystsoncombustionturbinesburninglandfillordigestergases.EmissionFactorTables H AppendixAincludesuncontrolledemissionfactorsfordiffusionflamecombustionturbinescombustingnaturalgasanddieselfuelathighloadsandalsoatvariousloadconditions.TheemissionfactorswerecalculatedfromturbinetestreportssummarizedintheEPACombustionTurbineEmissionsDatabase(seehttp://www.epa.gov/ttn/atw/combust/turbine/turbpg.htmlCombustionTurbineEmissionsDatabasev.4).Asthecombustionturbineloaddecreases,COandHAPemissionstypicallyincrease.Theemissionfactorsforhighloads(Tables1and2)shouldthereforenotbeusedtoestimateemissionsofturbinesoperatingatlowloads.TheemissionfactortablescanbeusedtodeterminetheemissionpotentialofuncontrolledHAPemissionsforcombustionturbines.Controlledemissionscanthenbeestimatedbyusingtheappropriateemissionreductionofthecontroltechnology.TheseemissionfactorsarebasedonHAPemissionteststhatwereperformedbetween1988andtheearly1990sandrepresentdiffusionflamecombustortechnology.Morerecentlyleanpremixcombustortechnologyturbineshavereplaceddiffusionflamecombustortechnologyturbines,andvirtuallyallnewcombustionturbinessoldareleanpremixcombustortechnologyturbines.Theseturbinesarediscussedinthefollowingsection. &  LeanPremixCombustion  &"% Thereareanestimated800existing'&ԀleanpremixstationarycombustionturbinesintheUnitedStates.Leanpremixtechnology,introducedinthe1990s,wasdevelopedtoreduce_NOx_emissionswithouttheuseofaddoncontrols.Inastagedleanpremixcombustion,theairandfuelarethoroughlymixedtoformaleanmixturebeforedeliverytothecombustor.Thestaged h+&* entrylimitstheflametemperatureandtheresidencetimeatthepeakflametemperature.Leanpremixcombustorsemitlowerlevelsof_NOx_,CO,formaldehyde,andotherHAPthandiffusionflamecombustionturbines.Thistechnologycanonlybeusedfornaturalgasfiredsources.TheEPArecentlyreceivednewemissionstestdataforeighttestsforformaldehydeonleanpremixstationarycombustionturbines.Thetestswereconductedonleanpremixstationarycombustionturbinesranginginsizefrom10MWto170MW.Theaverageformaldehydeemissionfactorforhigh(>80percent)loadsfromthesetestsis7.33E05lb/MMBtu.The95th $ t upperpercentilelevelis1.96E04lb/MMBtu.ComparisonoftheseemissionfactorstoemissionfactorsfordiffusionflamestationarycombustionturbinesequippedwithoxidationcatalystsystemsshowsthatHAPemissionsfromleanpremixstationarycombustionturbinesarelowerthanHAPemissionsfrom#XbmXX Xbm#diffusionflamestationarycombustionturbinesequippedwithoxidation $  catalystsystems XbmXXXbm.Thus,leanpremixcombustionisacomparabletechnologytooxidationcatalyst   systems. $X"   &"%   AppendixA:UncontrolledHAPEmissionFactorsforDiffusionFlameCombustionTurbinesCombustingNaturalGasandDieselFuelatHighLoadsandVariableLoads   Table1.HAPEmissionFactorsforNaturalGasFired#XbmXX Xbm#DiffusionFlame XbmXXXbmCombustion ` TurbinesforHighLoads իX XbmԀ# XbmX իC#(>80%) իX Xbm L  y  * ,ddd Xdd Xdd X(#(#,rdd ,Fdd , dd ,Hdd +  +  L +# XbmX ի# X XbmHAP ?,!` " ?  #Tests ?,!`  " ?!AverageEmissionFactor(lb/MMBtu) ?,!`   ?Range(MinMax) 7(&`  "   7Acetaldehyde UB    @6@U_6_ q@  "  @6 @ :`?3.95E-05:`?_3.95E05_ eRG " :`?3.95E-05 :`? e(1.10E058.60E05)# XbmX /!# X Xbm 2#! " 2Benzene VCh   &@11&@V_11_ rAh "  &@11 &@ h㈵>1.00E-05h㈵>_# XbmX x$# X Xbm1.00E05_ eRGh " h㈵>1.00E-05 h㈵> e(6.78E073.91E05)# XbmX &# X Xbm 2#!h " 2Formaldehyde VCt   4@204@V_20_ rAt "  4@20 4@  OmI?7.76E-04 OmI?_7.76E04# XbmX &# X Xbm_ eRGt "  OmI?7.76E-04  OmI? e(2.21E065.61E03) 4#!t " 4POM UB   @6@U_6_ q@ "  @6 @ ;^>4.38E-06;^>_4.38E06_ eRG " ;^>4.38E-06 ;^> e(1.15E061.06E05)# XbmX i(# X Xbm1'% "   1# XbmX +# Table2.HAPEmissionFactorsforDistillateOilFired#XbmXX Xbm#DiffusionFlame XbmXXXbmCombustion  TurbinesforHighLoads(>80%) իX Xbm x  *,ddrdd rFdd F dd Hdd H ,(#(#,rdd ,Fdd , dd ,Hdd +  + (x! +# XbmX իI,# X XbmHAP ?,!"" ?#Tests ?,!#" ?AverageEmissionFactor(lb/MMBtu) ?,!$" ?Range(MinMax)# XbmX, -# h XbmԀ 7(&%"   7Benzene UB8&  @3@U3 q@8'"  @3 @ k$ ?8.30E-05k$ ?# XbmX "/# X Xbm8.30E05 eRG8(" k$ ?8.30E-05 k$ ? e(1.40E051.25E04) 2#!8)" 2Cadmium UBD*  ?1?U1 q@D+"  ?1 ? v !>4.80E-06v !># XbmX ߀0# X Xbm4.80E06 eRGD," v !>4.80E-06 v !> eЄ 2#!D-" 2Chromium 6#. 61a eR!/" 34>1.08E-0534>e1.08E05 eRG0" 34>1.08E-05 34> e(1.02E051.15E05) 2#!1" 2Formaldehyde UBL2  @5@U_5_ q@L3"  @5 @  ĭ8?3.74E-04 ĭ8?_3.74E04# XbmX W2# X Xbm_ eRGL4"  ĭ8?3.74E-04  ĭ8? e(8.12E051.01E03) 2#!L5" 2Lead 6#X6 61a eR!X7" tR#>1.42E-05tR#>e1.42E05 eRGX8" tR#>1.42E-05 tR#> e(9.04E061.93E05) 2#!X9" 2Manganese UB:  ?1?U1 q@;"  ?1 ? Z(I?7.89E-04Z(I?7.89E04 eRG<" Z(I?7.89E-04 Z(I? eЄ 2#!=" 2Mercury UB!`>  ?1?U1 q@!`?"  ?1 ? v !>1.20E-06v !>1.20E06 eRG!`@" v !>1.20E-06 v !> eЄ 4#!!`A" 4POM UBl"B  @5@U_5 q@l"C"  @5 @ Jf??7.67E-05Jf?? q@l"C"  @5 @ 'eRC?1.04E-04'eRC?7.671.04E045_ eRGl"D" Jf??7.67E-05 Jf?? e(7.58E083񀄀3.10E04)# XbmX ߸5# X Xbm1'%l"E"   1# XbmX u=# ,X Xbm  # XbmX ,=# ,h Xbma0  # XbmX ,:># X XbmTwotestsconductedonthesameturbineusingdifferenttestmethods# XbmX ߌ># #LF(#(#    &!I Table3.HAPEmissionFactorsforNaturalGasFired#XbmXX Xbm+#DiffusionFlame XbmXXXbmCombustion  TurbinesforAllLoads իX Xbm   *,d drdd rFdd F dd Hdd H,(#(#,rdd ,Fdd , dd ,Hdd +  + L +# XbmX ի@# X XbmHAP ?,!" ?#Tests ?,!" ?AverageEmissionFactor(lb/MMBtu) ?,!" ?Range(MinMax) 7(&"   7Acetaldehyde UB \  @7@U_7_ q@ \ "  @7 @ f4M38?4.51E-05f4M38?_4.51E05_ eRG \ " f4M38?4.51E-05 f4M38? e(1.10E058.60E05)# XbmX ߭A# X Xbm 2#! \ " 2Benzene VCh    2@182@V_18_ rAh  "  2@18 2@ d#?1.45E-04d#?_# XbmX D# X Xbm1.45E04_ eRGh " d#?1.45E-04 d#? e(6.78E072.36E03)# XbmX RF# X Xbm 2#!h " 2Formaldehyde VC   <@28<@V_28_ rA "  <@28 <@ c#g?2.92E-03c#g?_2.92E03# XbmX &G# X Xbm_ eRG " c#g?2.92E-03 c#g? e(2.21E062.54E02) 4#! " 4POM UB p   @8 @U_8_ q@ p"   @8  @ Q؎>4.32E-06Q؎>_4.32E06_ eRG p" Q؎>4.32E-06 Q؎> e(1.15E061.06E05)# XbmX ߻H# X Xbm1'% p"   1# XbmX [K# Table4.HAPEmissionFactorsforDistillateOilFired#XbmXX Xbm?#DiffusionFlame XbmXXXbmCombustion ,  TurbinesforAllLoads իX Xbm    *,ddrdd rFdd F dd Hdd H,(#(#,rdd ,Fdd , dd ,Hdd +  + x +# XbmX իL# X XbmHAP ?,!," ?#Tests ?,!," ?AverageEmissionFactor(lb/MMBtu) ?,!, " ?Range(MinMax)# XbmX, .N# h XbmԀ 7(&,!"   7Acetaldehyde UB8"  @2@U2 q@8#"  @2 @ wS%%>3.03E-05wS%%>3.03E05 eRG8$" wS%%>3.03E-05 wS%%> e(2.24E053.82E05) 2#!8%" 2Benzene UB&  @3@U3 q@'"  @3 @ k$ ?8.30E-05k$ ?# XbmX mO# X Xbm8.30E05 eRG(" k$ ?8.30E-05 k$ ? e(1.40E051.25E04) 2#!)" 2Cadmium UB@*  ?1?U1 q@@+"  ?1 ? v !>4.80E-06v !># XbmX eR# X Xbm4.80E06 eRG@," v !>4.80E-06 v !> eЄ 2#!@-" 2Chromium 6#L. 61a eR!L/" 34>1.08E-0534>e1.08E05 eRGL0" 34>1.08E-05 34> e(1.02E051.15E05) 2#!L1" 2Formaldehyde UB2   @8 @U8 q@3"   @8  @ ZQf3?2.96E-04ZQf3?_2.96E04# XbmX 1.42E-05tR#>e1.42E05 eRGT8" tR#>1.42E-05 tR#> e(9.04E061.93E05) 2#!T9" 2Manganese UB`:  ?1?U1 q@`;"  ?1 ? Z(I?7.89E-04Z(I?7.89E04 eRG`<" Z(I?7.89E-04 Z(I? eЄ 2#!`=" 2Mercury UB >  ?1?U1 q@ ?"  ?1 ? v !>1.20E-06v !>1.20E06 eRG @" v !>1.20E-06 v !> eЄ# XbmX }W# X Xbm 2#! A" 2Nickel UB hB  ?1?U1 q@ hC"  ?1 ? 'eRC ?5.20E-05'eRC ?5.20E05 eRG hD" 'eRC ?5.20E-05 'eRC ? eЄ 4#! hE" 4POM UBt!F  @5@U_5_ q@t!G"  @5 @ Jf??7.67E-05Jf?? q@t!G"  @5 @ 'eRC?1.04E-04'eRC?_7.67E05# XbmX ߬\# X Xbm_ eRGt!H" Jf??7.67E-05 Jf?? e(7.58E083.10E04)# XbmX [`# X Xbm1'%t!I"  1# XbmX 'a# ,X Xbm  a0  # XbmX ,a# X XbmTwotestsconductedonthesameturbineusingdifferenttestmethods# XbmX a# ,X Xbm#TJ(#(# # XbmX ,b#  $L M   AttachmentAb   L  MEMORANDUM:DATE:  ` August19,1999  L  SUBJECT:  ` ComparisonofCOOxidationCatalystswiththeSCONOxTMSystem  $   Oxidationcatalystshavebeeninstalledonstationarycombustionturbinesforthepurposeofcontrollingemissionsofcarbonmonoxide(CO)andsomevolatileorganiccompounds(_VOC_).Theseoxidationcatalystshavethepotentialtooxidizeorganichazardousairpollutants(HAPs)aswell.Therefore,theyarebeingconsideredaspotential_MACT_Ԁcontroldevicesforcombustionturbines.ThepurposeofthismemorandumistodocumenttheachievableemissionsreductionlevelsforCOemissionsfromgasturbineswithCOoxidationcatalysts.ItisunknownifsourcetestshavebeenperformedonCOcatalysts;however,emissiontestingdocumentationofacomparablesystemwhichincludesCOoxidationwasobtained.ThissystemisknownastheSCONOxTM H system.SCONOxTMisacomparabletechnologytoCOoxidationcatalysts.Itemploysapreciousmetal   catalystfortheremovalofCOviacatalyticoxidation,justasaCOoxidationcatalystdoes.AcorrelationcanthereforebemadefortheefficienciesoftheSCONOxTMsystemandCOcatalysts.  ThedifferenceinthecatalyticoxidationtechnologyisthattheSCONOxTMsystemusesa  chemicallymodifiedcatalystsothatthecatalystalsoremovesNOX.Thesechemicalmodificationsarenotbelievedtoaffecttheoxidationcatalystperformance.Thefollowingsectionsdescribeeachtechnologyingreaterdetail. COOxidationCatalysts  #l! TheCOoxidationcatalystisanaddondevicethatisplacedintheturbineexhaustduct.Itpromotestheoxidationofhydrocarboncompoundstocarbondioxide(CO2)andwater(H2O)as %0!$ theemissionstreampassesthroughthecatalystbed.Thecatalystisusuallyapreciousmetalsuchasplatinum,palladium,orrhodium.Otherformulations,suchasmetaloxidesforemissionstreamscontainingchlorinatedcompounds,arealsoused.Theoxidationprocesstakesplacespontaneously,withouttherequirementforintroducingreactants.TheperformanceofaCOoxidationcatalystisaffectedbyfactorssuchasoperatingtemperatureandthepresenceofpoisonsintheemissionstream. h+&* ЇOxidationcatalystsaretypicallyusedonturbinestoachievecontrolofCOemissions,especiallyturbinesthatusesteaminjection,whichcanincreasetheconcentrationsofCOandunburnedhydrocarbonsintheexhaust.Theyarealsobeingusedtoreduce_VOC_Ԁemissions.ItisexpectedthatexistingcatalystssimilartothoseinuseforCOand_VOC_ԀalsooxidizeorganicHAPs. SCONOxTM  L  TheSCONOxTMCatalyticAbsorptionSystemisaproprietarycatalystdevelopedbyGoalLine $ t EnvironmentalTechnologiesLLC.Thesystemdesignisbasedoncatalyticoxidationandabsorptiontechnologies.ThecatalyticfunctionsofthesystemaretheoxidationofCOtoCO2  L  andNOtoNO2.TheCO2passesthroughthesystemandexitswiththeexhaust.TheNOX  8  (primarilyintheoxidizedformofNO2)issubsequentlyabsorbedonthetreatedsurfaceofthe $  catalyst.TheNOXiseventuallyreleasedfromthecatalystasN2viaaseriesoflouversthatopen   andcloseovereachsectionofthecatalystforshortperiods.ThecatalystisperiodicallyregeneratedonceitissaturatedwithNOXbypassingacontrolledmixtureof regenerationgasesoversectionsofthecatalystforshortperiods.Thesegasesarenonhazardous.ThechemistryinvolvedineachoftheprocessesthatoccurintheSCONOxTMcatalystisas \ follows:Oxidation&AbsorptionCycle  p   CO+1/2O2󀄄>CO2 H   NO+1/2O2󀄄>NO2 4   2NO2+K2CO3󀄄>CO2+KNO3+KNO2   RegenerationCycle    KNO3+KNO2+4H2+CO2󀄄>K2CO3+4H2O+N2 l ProductionofRegenerationGas D!   CH4+1/2O2+1.88N2󀄄>CO+2H2+1.88N2 #l!   CO+2H2+H2O+1.88N2󀄄>CO2+3H2+1.88N2 $X" TheSCONOxTMsystemwasdeterminedLowestAchievableEmissionRate(LAER)bytheU.S. %0!$ EPAinJulyof1997,andBestAvailableControlTechnology(BACT)bytheSouthCoastAirQualityManagementDistrictofCaliforniainSeptemberof1997.ThesystemisdesignedtoreducebothCOandNOXemissionsfromnaturalgasfiredpowerplantstolevelsbelowambientconcentrations.COemissionsof1ppmandNOXemissionsof2ppmareguaranteedbythemanufacturer.However,thesystemhasalsoproventobeeffectiveinremovingVOCsandHAPs. h+&* _ TestingOxidationCatalystforHAPReduction   AcombustionturbineequippedwithaSCONOxTMcatalystsystemwastestedonMarch14,1997,  byDeltaAirQualityServices.Sampleswerecollectedattheinlettothecatalystandattheexhaustfromthecogenerationunit(turbineexhauststack)andanalyzedforformaldehyde,acetaldehyde,andbenzene.Thetestrevealedinletandoutletconcentrationsofformaldehydeof358ppband10ppb,respectively.Acetaldehydewasreducedfrom13.6ppbdownto0.8ppb.Formaldehydeandacetaldehydereportedlywerereducedby97%and94%,respectively.Noconclusionregardingthecontrolefficiencyforbenzenecouldbedrawnsincethelevelsbeforeandafterthecatalystwerebothverylowandwithin0.05partsperbillionofeachother.COwasreducedfrom5075ppmtobelow2ppm(9697%efficiency)duringthetestingperiod.  ThemainpracticallimitationofSCONOxTMoverCOoxidationcatalystsisthemaximum   operatingtemperature(700oF)atwhichSCONOxTMcanoperate.Thistemperaturelimitationis   causedbythechemicalmodificationofthecatalystforNOXcontrolandisnotalimitationoftheoxidationcatalyst.TheuseoftheSCONOxTMcatalystforsimplecycleinstallationsmaybe   limitedduetothetemperaturelimitation.Inaddition,SCONOxTMhasonlybeenproveneffective p onnaturalgasfiredinstallations.Additionalresearchonliquidandcoalfuelcombustioniscurrentlyinprogress.StandardCOoxidationcatalystsarecurrentlybeingusedonbothnaturalgasandliquidfuelfiredunits. Conclusion   \ SincetheoxidationprocessthatoccursintheSCONOxTMcatalystisidenticaltothatofCO 4 catalysts,theefficienciesofaCOcatalystcanbeexpectedtobesimilartothatofaSCONOxTM   catalyst.TheremovalefficienciesoftheSCONOxTMcatalystshavebeendemonstratedthrough   testingtobeatleast90%forformaldehydeandacetaldehyde.#XbmXX Xbm?L#