Sorbent Injection for Small ESPMercury ControlKatherine DombrowskiURS CorporationDOE/NETL Mercury Control TechnologyConferenceDecember 11, 2006DE-FC26-03NT4198711-Dec-06DE-FC26-03NT41987Project TeamProject TeamPierina Noceti(COR)Nick IrvinKen McBeeCarl RichardsonKatherine DombrowskiRamsay ChangMark BerrySharon SjostromGreg NewmanLarry Rapski 

# Apogee ScientificTim Ebner11-Dec-06DE-FC26-03NT41987Project ObjectivesProject ObjectivesEvaluate sorbent injection for Hg control inbituminous flue gas across small-sizedelectrostatic precipitators (ESPs)•Mercury removal performance & variability•Optimal process conditions•Balance of plant effects•ESP performance•FGD operation•Effects on byproduct ash, gypsum11-Dec-06DE-FC26-03NT41987Project BackgroundProject Background■Financial Assistance Program DE-FC26-03NT41987■Most previous ACI testing with ESPs performedon relatively large units-High levels of Hg removal possible-No apparent detrimental effects on ESP performance■70% of utility ESPs have SCA <300 ft2/1000 acfm-Sorbent injection performancein this size range notcurrently known-Effects on ESP performance11-Dec-06DE-FC26-03NT41987Project BackgroundProject Background■Full-scale activated carbon injection tests atSouthern Company’s Georgia Power Plant Yates-Units 1 and 2■100 MW; low-sulfur eastern bituminous coal-ESPs with SCA <200 ft2/1000 acfm■Full-scale sorbent injection tests at Reliant Energy’sShawville Station Unit 3-175 MW; medium-sulfur eastern bituminous coal-Two ESPs configured in series■SCA = 82, 230 ft2/1000 acfm, respectively11-Dec-06DE-FC26-03NT41987Project StatusProject StatusAll field testing completed■Plant Yates Testing-Units 1 and 2 Parametric Tests(Spring-04)-Unit 1 Long-term test (Fall-04)-Site Reports Completed-Economic Analysis Completed■Shawville-3 Testing-Parametric tests (July-06)-Data analysis on-goingTest PlanTest PlanBaseline TestsBaseline TestsParametric TestParametric TestLong-term teststerm testsCost AnalysisCost AnalysisFinal ReportFinal Report11-Dec-06DE-FC26-03NT41987Plant Yates Unit 1 ConfigurationPlant Yates Unit 1 ConfigurationJBRAbsorberBoilerStackAPHInlet Flue GasSamplingESP OutletSamplingFGD OutletSamplingSorbentInjectionESP11-Dec-06DE-FC26-03NT41987Summary – Plant Yates ResultsSummary – Plant Yates ResultsCarbonNameManufacturerCarbon DescriptionCost ($/lb)Darco FGDTMNorit AmericasTx lignite-derived activated carbon;baseline carbon; 19μm mean particlesize0.50Super HOKRWERhinebraunGerman lignite-derived activatedcarbon; 23μm mean particle size0.35*NH CarbonNingxiaHuahuiActivatedCarbon Co.Chinese chemically treatedbituminous-derivedactivated carbon;24μm mean particle size0.8811-Dec-06DE-FC26-03NT41987Summary – Plant Yates ResultsSummary – Plant Yates ResultsHg Removal Across Unit 1 ESP11-Dec-06DE-FC26-03NT41987Summary – Plant Yates ResultsSummary – Plant Yates ResultsESP Hg Removal Due to Activated CarbonUnit 111-Dec-06DE-FC26-03NT41987Summary – Plant Yates ResultsSummary – Plant Yates Results0%10%20%30%40%50%60%70%80%90%100%02468101214FGDCarbon InjectionRate (lb/MMacf)

% Hg Total Removal at ESP OutletFullHalfLowNH3NoneFlueGasConditioning:ESP Hg Removal Due to Activated CarbonUnit 211-Dec-06DE-FC26-03NT41987Mercury Removal during Long-term TestMercury Removal during Long-term Test0%10%20%30%40%50%60%70%80%90%100%11/13/04 11/18/04 11/23/04 11/28/04 12/3/04 12/8/04 12/13/04

Vapor Phase Hg Removal (%)024681012141618 HOK Injection Rate (lb/Macf)% Hg Removal Across System% Hg Removal Across ESPHOK Injection RateInjection RateSystem RemovalESP Removal11-Dec-06DE-FC26-03NT41987ESP Arcing During Long-term InjectionESP Arcing During Long-term Injection051015202530354010/12 10/19 10/26 11/2 11/9 11/16 11/2311/30 12/7 12/14 12/21 12/28 1/4 1/11

Carbon Injection Rate (lb/Macf); Arc Rate (apm)Field 1A arc rateCarbon Injection Rate (lb/Macf)1A Arc RateLT Injection Test11-Dec-06DE-FC26-03NT41987ESP Outlet Particulate ConcentrationsESP Outlet Particulate Concentrations11-Dec-06DE-FC26-03NT41987$0$500,000$1,000,000$1,500,000$2,000,000$2,500,000$3,000,000$3,500,000$4,000,000$4,500,000$5,000,000HOK Darco Hg-2004 Darco Hg-2005 Darco Hg-LH NH Carbon

Annual Cost ($/year)Capital Equipment AmortizationCarbon TransportationCarbon CostAnnual Costs fora Targeted 35%Reduction in ESP Outlet VaporPhase MercuryConcentrationEconomic Analysis – Plant Yates DataEconomic Analysis – Plant Yates Data11-Dec-06DE-FC26-03NT41987Summary of ResultsSummary of Results■Large variations in ESP inlet Hg concentration■Vapor Hg removals typically 65 to 85% across ESPat 4 lb/Macf-With ACI only, outlet emissions were 0.5-3.5 lb/TBtu-Combination of ACI/JBR, outlet emissions were lessthan 2 lb/TBtu■ESP Effects-Increase in ESP arcing with ACI-Particulate breakthrough measured at ESP outlet-Carbon particles found inM17 filters and JBR scrubber11-Dec-06DE-FC26-03NT41987Shawville 3 ConfigurationShawville 3 Configuration•Unit 3 BoilerStackESP1AESP1BESP2AESP2BLocation ALocation BLocation CCarbonInjectionPhase ICarbonInjectionPhases IIAPHAPH11-Dec-06DE-FC26-03NT41987Sorbents Evaluated at ShawvilleSorbents Evaluated at ShawvilleSorbentSupplierDescriptionSuper HOKRWE(Germany)Activated German lignite;d50= 24 μmHOK – CoarseRWE(Germany)Activated German lignite;d50= 63 μmDarco HgNorit Americas(Marshall, TX)Activated Texas ligniteDarco Hg-LHNorit Americas(Marshall, TX)Activated Texas lignite treatedwith bromineDarco Hg/HighCalcium HydratedLimeNorit Americas (Marshall, TX/Chemical Lime (Dallas, TX)30/70 mixture of Darco Hg withhigh surface area hydrated lime(for SO3control)11-Dec-06DE-FC26-03NT41987Shawville 3 SummaryShawville 3 Summary■Baseline Testing-Hg values range: 26 – 43 μg/Nm3@ 3% O2-Oxidation high: >80% at ESP-2 outlet-Hg removal to fly ash occurs upstream of ESPs-Little to no Hg removal across ESPs■Sorbent Injection Testing-Effect of injection rate and location-Co-injection of high surface area lime■Pre-mixed; separate injection configurations-Impact of SNCR operation11-Dec-06DE-FC26-03NT41987Shawville 3 Summary – Super HOKInjectionShawville 3 Summary – Super HOKInjection01020304050607080901000.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0Injection Rate (lb/MMacf)

Total Mercury Removal (%)ESP 1/2 HOKESP 1 only HOKESP 2 HOKESP 2 HOK CoarseESP 2 HOK 48-hourParametric Testing - HOK Carbon11-Dec-06DE-FC26-03NT41987Shawville 3 Summary – Super HOK InjectionShawville 3 Summary – Super HOK Injection01020304050607080901007/30/063:007/30/069:007/30/0615:007/30/0621:007/31/063:007/31/069:007/31/0615:007/31/0621:008/1/063:008/1/069:00

Percent Removal, Total Mercury (%)48-hour continuous injection at 10.6 lb/Macf into ESP 211-Dec-06DE-FC26-03NT41987Shawville 3 SummaryShawville 3 SummaryDarco-Hg Parametric Testing01020304050607080901000 2 4 6 8 10 12 14 16Injection Rate (lb/MMacf)

Total Vapor-Phase Mercury Removal (%)ESP 1/2 - Darco HgESP 1 only - Darco HgESP 2 - Darco HgESP 2 - Darco Hg-LHParametric Testing – Darco Hg11-Dec-06DE-FC26-03NT41987Shawville 3 Summary - HOK vs DarcoShawville 3 Summary - HOK vs Darco01020304050607080900.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0Carbon InjectionRate (lb/MMacf)

Total Mercury Removal (%)ESP1 Darco HgESP 1 HOKESP 2 Darco HgESP 2 HOKSNCR Off11-Dec-06DE-FC26-03NT41987Shawville 3 Summary – Comparison of SO3Levels and Sorbent Mercury RemovalShawville 3 Summary – Comparison of SO3Levels and Sorbent Mercury Removal01020304050607080900.00.51.01.52.0ESP 2 Outlet SO3(ppmv)

Total Mercury Removal (%)Lime ESP 1/ Carbon ESP 2Injection (ESP 2 Removal)Premix ESP 1 Injection (ESP1/2 Removal)SNCR OFFCarbon 4.9 lb/MMacfLime 200 lb/hrSNCR ONCarbon 3.8 lb/MMacfLime 50 lb/hrSNCR OFFCarbon 4.9 lb/MMacfLime 100 lb/hrSNCR OFFCarbon 4.8 lb/MMacfLime 0 lb/hrSNCR OFFCarbon 0 lb/MMacfLime 0 lb/hrSNCR ONCarbon 5.5 lb/MMacfLime 181 lb/hrSNCR ONCarbon 3.5 lb/MMacfLime 116 lb/hrSNCR ONCarbon 0 lb/MMacfLime 0 lb/hr11-Dec-06DE-FC26-03NT41987Shawville SummaryShawville Summary■High levels of mercury removal achieved acrosssmall ESPs■Better performance with Darco-Hg than Super HOK■Apparent effect of SO3at very low levels (<2 ppm)■ESP performance-Electrical properties (TBD)-PM removal (single-point M17)■Baseline outlet emissions–0.013 to 0.020 gr/dscf■ACI outlet emissions–0.009 to 0.030 gr/dscf11-Dec-06DE-FC26-03NT41987Future Project PlansFuture Project Plans■Completion of Shawville data/resultscharacterization(Q1FY07)■Complete Shawville Site Report(Q1FY07)■Project Close-out