Philip Elliott, Thomas Riethmann,Dr. Hermann Brüggendick,Dr. Hermann Winkler,Dr. Bernhard W. Vosteen, Hans HartensteinFull Scale Testing of aNovel Mercury ControlStrategyFebruary 2010 – EUEC ConferenceThis diagram shows, that the ways toinfluence the mercury concentrationare limited.Mercury can either be prevented fromentering the process or has to beremoved from the process via ash, waste water, flue gas or byproducts(e.g. gypsum).If byproducts are sold the amountof mercury in them is limited.Regulation limits the amount of mercury discharged via flue gas andwaste water.AshByproductsWaste WaterFlue Gascoal incl. mercuryPower PlantProcessEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction, use or disclosure to third parties without express authority is strictly forbidden.The Path of MercuryPAC Injection Prior to Particulate ControlDevice• Injection of PAC to Combine with Mercury• Captured in Baghouse or Precipitator• Requires 3-10 lbs of PAC per MMacfmCaptured in Wet FGD• Oxidized Mercury Dissolved in ScrubberSlurryEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction, use or disclosure to third parties without express authority is strictly forbidden.Typical Methods for Mercury CaptureDeNOxWFGDESPCaBr21stHydrocyclone2ndHydro-cycloneHg-free GypsumStackPACLow-Hg Sludge FractionEnhanced Mercury AbatementCaBr2to Coal and PAC to WFGDwith Selective Mercury Precipitation in WWTHg-richPACVOSTEENConsultingEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.Comparison of TechnologiesTraditional PAC InjectionEvonik TechnologyBaghouse RequiredNo Baghouse RequiredContamination of Fly AshNo Contamination of FlyAshRequires 3-10 lbs of PACper MMacfmRequires 0.2 lbs PAC perMMacfmWet FGDEvonik TechnologyReemission of MercuryVery limited reemissionContamination of GypsumGypsum Quality notAffectedPurpose of Test1. To Determine if≥90 % Reduction withoutSCR is Possible2. To Determine if CaBr2Injection Affects FGDand WWT Process3. To Determine if PAC Injection Affects FGDand WWT Processes4. To Determine what Chemical Factors Affectsthe ProcessEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.PAC Dosing stationCaBr2-DosingWFGDAbsorberKesselSCRDeNOx withReheaterGypsumcoal blend~ 1ppm HgTagesbunkerfeedercoalmillfly-ash recycleUnit 5375 MWthG~Hg-speciesafter boilerHg-speciesafter FGDHg-speciesat stack2-stage WWTsludge partlyrecycledtocombustionHgsinkTail-End SCR –Plant Marl (375MW)WFGDQuenchEvonikEnergyServicesLLC ©2010.Wereserve all right in thisdocument and intheinformation contained therein.Reproduction,use or disclosure to thirdparties without express authorityis strictlyforbidden.1. Injected a 52 % Solution of CaBr2ontoeach of the 3 Coal Belts2. Three injection points into each feeder3. Injection rates to maintain 250 ppm of Brin coal with respect to HgInjection of CaBr2Onto CoalFeedersEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.1. Injection Through a Solution of ActivatedCarbon and Water2. Injected into the Scrubber through theAbsorber Recycle Pump3. Maintain a Constant Concentration ofPAC in the AbsorberInjection of PAC into FGDEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.Baseline Results at Marl Unit 5Flue Gas InHg Outlet<0.3 Hg2+2.2 Hgo<2.5 Hg totalHg Inlet8.5 Hg2+1.5 Hgo10.0 Hg totalFlue Gas OutletHg-concentration inabsorber solution approx. 300-500 ppbHg capture rate ~ 75 %Evonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.55 gpm wastewaterdischargeFlue Gas InHg Outlet<0.4 Hg2+0.1 Hgo<0.5 Hg totalHg Inlet9.9 Hg2+0.1 Hgo10.0 Hg totaldiscontinuous dosingof PAC (make-up)Hg-concentration in absorber solution after initial dosing of PAC approx. 30 ppbFlue Gas OutletHg capture rate above 95 %CaBr2& PAC Results at Marl Unit 5PACCaBr2Evonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.Chemical Process EffectChanged Slurry Chemistry to Determine Affect• 0.2 lbs PAC added per MMacfm of flue gas lowers theHg-concentration from 10.0 μg/m3to below 0.5 μg/m3Hg in the purified gas.• Oxidized Hg is adsorbed within the FGD, elemental Hgpasses through (nearly) unaffected. Hg oxidation e.g.by CaBr2is required.• The PAC/gypsum mixture can be separated completelyusing hydrocyclones (gypsum whiteness unaffected).• Various chemical factors affect capture rate• Costs:- Investment costs for PAC dosing station: $ 250,000- Operating costs:13 tons PAC/a x $0.50/lb = $ ~ 13,000/yearConclusionsEvonik Energy Services LLC © 2010. We reserve all right in this document and in the information contained therein. Reproduction,use or disclosure to third parties without express authority is strictly forbidden.placeholder title visualQuestions ?Contact North America: Philip ElliottEmail:philip.elliott@evonik-es.usContact Europe: Thomas RiethmannEmail:thomas.riethmann@evonik.com28.05.2008 | Evonik_BL_Renewable_Energies_E.pptPage 15