EPA Method 16

966METHOD16-SEMICONTINUOUSDETERMINATIONOFSULFUREMISSIONSFROMSTATIONARYSOURCESNOTE:Thismethoddoesnotincludeallofthespecifications(e.g.,equipmentandsupplies)andprocedures(e.g.,samplingandanalytical)essentialtoitsperformance.Somematerialisincorporatedbyreferencefromothermethodsinthispart.Therefore,toobtainreliableresults,personsusingthismethodshouldhaveathoroughknowledgeofatleastthefollowingadditionaltestmethods:Method1,Method4,Method15,andMethod16A.1.0ScopeandApplication.1.1Analytes.AnalyteCASNo.SensitivityDimethyldisulfide[(CH3)2S2]62-49-2050ppbDimethylsulfide[(CH3)2S]75-18-350ppbHydrogensulfide[H2S]7783-06-450ppbMethylmercaptan[CH4S]74-93-150ppb1.2Applicability.Thismethodisapplicableforthedeterminationoftotalreducedsulfur(TRS)compoundsfromrecoveryfurnaces,limekilns,andsmeltdissolvingtanksatkraftpulpmillsandfuelgascombustiondevicesatpetroleumrefineries.967NOTE:Themethoddescribedbelowusestheprincipleofgaschromatographic(GC)separationandflamephotometricdetection(FPD).Sincetherearemanysystemsorsetsofoperatingconditionsthatrepresentuseablemethodsofdeterminingsulfuremissions,allsystemswhichemploythisprinciple,butdifferonlyindetailsofequipmentandoperation,maybeusedasalternativemethods,providedthatthecalibrationprecisionandsamplelinelosscriteriaaremet.1.3DataQualityObjectives.Adherencetotherequirementsofthismethodwillenhancethequalityofthedataobtainedfromairpollutantsamplingmethods.2.0SummaryofMethod.2.1Agassampleisextractedfromtheemissionsourceandanaliquotisanalyzedforhydrogensulfide(H2S),methylmercaptan(MeSH),dimethylsulfide(DMS),anddimethyldisulfide(DMDS)byGC/FPD.ThesefourcompoundsareknowncollectivelyasTRS.3.0Definitions.[Reserved]4.0Interferences.4.1Moisture.Moisturecondensationinthesampledeliverysystem,theanalyticalcolumn,ortheFPDburnerblockcancauselossesorinterferences.Thisispreventedbymaintainingtheprobe,filterbox,andconnectionsata968temperatureofatleast120EC(248EF).MoistureisremovedintheSO2scrubberandheatingthesamplebeyondthispointisnotnecessarywhentheambienttemperatureisabove0EC(32EF).Alternatively,moisturemaybeeliminatedbyheatingthesampleline,andbyconditioningthesamplewithdrydilutionairtoloweritsdewpointbelowtheoperatingtemperatureoftheGC/FPDanalyticalsystempriortoanalysis.4.2CarbonMonoxide(CO)andCarbonDioxide(CO2).COandCO2haveasubstantialdesensitizingeffectontheflamephotometricdetectorevenafterdilution.Acceptablesystemsmustdemonstratethattheyhaveeliminatedthisinterferencebysomeproceduresuchaselutingthesecompoundsbeforeanyofthecompoundstobemeasured.CompliancewiththisrequirementcanbedemonstratedbysubmittingchromatogramsofcalibrationgaseswithandwithoutCO2inthediluentgas.TheCO2levelshouldbeapproximately10percentforthecasewithCO2present.ThetwochromatogramsshouldshowagreementwithintheprecisionlimitsofSection10.2.4.3ParticulateMatter.Particulatematteringassamplescancauseinterferencebyeventualcloggingoftheanalyticalsystem.ThisinterferenceiseliminatedbyusingtheTeflonfilteraftertheprobe.9694.4SulfurDioxide(SO2).Sulfurdioxideisnotaspecificinterferantbutmaybepresentinsuchlargeamountsthatitcannoteffectivelybeseparatedfromtheothercompoundsofinterest.TheSO2scrubberdescribedinSection6.1.3willeffectivelyremoveSO2fromthesample.5.0Safety.5.1Disclaimer.Thismethodmayinvolvehazardousmaterials,operations,andequipment.Thistestmethodmaynotaddressallofthesafetyproblemsassociatedwithitsuse.Itistheresponsibilityoftheuserofthistestmethodtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortoperformingthistestmethod.5.2HydrogenSulfide.Aflammable,poisonousgaswiththeodorofrotteneggs.H2Sisextremelyhazardousandcancausecollapse,coma,anddeathwithinafewsecondsofoneortwoinhalationsatsufficientconcentrations.Lowconcentrationsirritatethemucousmembranesandmaycausenausea,dizziness,andheadacheafterexposure.6.0EquipmentandSupplies.6.1.SampleCollection.Thefollowingitemsareneededforsamplecollection.6.1.1Probe.TeflonorTeflon-linedstainlesssteel.Theprobemustbeheatedtopreventmoisturecondensation.970Itmustbedesignedtoallowcalibrationgastoentertheprobeatornearthesamplepointentry.Anyportionoftheprobethatcontactsthestackgasmustbeheatedtopreventmoisturecondensation.Figure16-1illustratestheprobeusedinlimekilnsandothersourceswheresignificantamountsofparticulatematterarepresent.Theprobeisdesignedwiththedeflectorshieldplacedbetweenthesampleandthegasinletholestoreducecloggingofthefilterandpossibleadsorptionofsamplegas.Asanalternative,theprobedescribedinSection6.1.1ofMethod16Ahavinganozzledirectedawayfromthegasstreammaybeusedatsourceshavingsignificantamountsofparticulatematter.6.1.2ParticulateFilter.50-mmTeflonfilterholderanda1-to2-micronporosityTeflonfilter(availablethroughSavillexCorporation,5325Highway101,Minnetonka,Minnesota55343).Thefilterholdermustbemaintainedinahotboxatatemperatureofatleast120EC(248EF).6.1.3SO2Scrubber.Three300-mlTeflonsegmentedimpingersconnectedinserieswithflexible,thick-walled,Teflontubing.(ImpingerpartsandtubingavailablethroughSavillex.)Thefirsttwoimpingerscontain100mlofcitratebufferandth