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Mercury Puzzle Hg(0), Hg(II), Hg p. Alvaro Linero, P.E. Administrator, Special Projects Bureau of Air Regulation. Emissions and Processes. DEP Contract to Test some Facilities Three Coal- Fueled Power Plants Two Cement Kilns, plus a Compliance Test Waste-to-Energy (WTE) Compliance Tests
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Mercury Puzzle Hg(0), Hg(II), Hgp Alvaro Linero, P.E.Administrator, Special ProjectsBureau of Air Regulation
Emissions and Processes DEP Contract to Test some Facilities Three Coal- Fueled Power Plants Two Cement Kilns, plus a Compliance Test Waste-to-Energy (WTE) Compliance Tests Miscellaneous Industries Hg-CEMS (Continuous Emissions Monitoring Systems)
Some Nomenclature, Proportion Micrograms Hg per dry standard cubic meter Pounds Mercury per Year (lb Hg/yr) LittleSubstantiala LotPotent 0.1 1 10 100 µg Hg/dscm 1 10 100 1000 lb Hg/year
More Nomenclature Kilowatt-hour (KWH) 1,000 KWH = Megawatt-hour (MWH) Million (or 106) MWH = Terawatt-hour (TWH) 1 x 10-6 lb/MWH = 1 lb Hg/TWH = 0.1 lb/TBtu ppb = parts per billion lb Hg/million tons of clinker = lb Hg/MT clinker
25% Removal Hgp Old 360 MW Coal-fueled Unit High NOX Flue Gas Higher NOxLower CO Cold Electrostatic Precipitator (ESP) 150 lb Hg/yr Hg(0) = Elemental (gas) Hg(II) = Reactive (salts like HgCl2) Hgp = Particle Bound 75% Coal & XS Air200 lb Hg/yr Eastern Coal Hg0 >2500 °F 25% 50 lb Hg/yr Fly Ash to Concrete, Cement Kiln Storage, Waste I don’t actually have data for this case
45% Removal Hgp 360 MW Coal-fueled Unit Tuned for Low NOX Flue Gas C Cold Electrostatic Precipitator (ESP) 110 lb Hg/yr Flue gas carbon (C) can behave much like activated C Overfire Air 55% Coal & Air200 lb Hg/yr Hg0 Low NOxBurners (LNB) >2500 °F 72 lb/TWH 90 ppb Hg 10.5% Ash Eastern Coal 45% 90 lb Hg/yr 40 lb/TWH4.9 µg/dscm64% Hg(II) Carbon and Hg-Enriched Fly Ash to Concrete, Cement Kiln, Storage, Waste 385 ppb Vacated EPA Hg limit for new units was 21 lb/TWH
Wet Flue Gas Desulfurization (FGD) for SO2 Limestone or Lime Slurry FGD Flue Gas C ESP 40 lb Hg/yr OFA Soluble Hg salts absorbed or reacted in FGD Scrubber Coal & Air200 lb Hg/yr 20% Hg0 LNB >2500 °F 45% Removal Hgp Hg(II) 45% 90 lb Hg/yr 16 lb/TWH2 µg/dscm 85% Hg(0) 35% 70 lb Hg/yrSludge, Gypsum Hg Salts Carbon and Hg-Enriched Fly Ash to Concrete, Cement Kiln, Storage, Waste 385 ppb
Selective Catalytic Reduction (SCR) for NOX Limestone or Lime Slurry FGD ESP Overfire Air 10 lb Hg/yr Coal & Air 200 lb Hg/yr Elemental Hg (0) oxidized to Hg (II) by catalyst Hg0 LNB SCR >2500 °F Flue Gas C 45% Removal Hgp Hg(II) Ammonia (NH3) 45% 50% 3.2 lb/TWH0.5 µg/dscm 69% Hg(0) 90 lb Hg/yr 100 lb Hg/yrSludge, Gypsum Hg Salts NH3, Carbon, Hg-Enriched Fly Ash Concrete, Cement Kiln, Waste or Fly Ash Remediation
Florida Cement Industry 10,000,000 tons per year clinker Ten cement kilns Demand is down Five in operation (slack demand) Two are temporarily down Three new startups (also slack) Suwannee American Vulcan American CEMEX N. Brooksville CEMEX S. Brooksville Titan America CEMEX Miami
Raw Mill Off, Little Hg In 0.8 µg/dscm92% of time3 lb/yrHg(0)New Kiln Limit41 µg/dscm 400 µg/dscm8% of time117 lb/yrHg(II)New Kiln Limit41 µg/dscm 1 MT Clinker Cement Kiln, Raw Mill On Scrubber ? Filter LEGEND Gas Solid Preheater Exhaust Filter Dust To Cement Mill Separators Preheater Feed 1 MT/yr of Clinker Fuel Hg Fuel Hg Meal & Hg Stored Fuel Hg Fuel Hg RAW MEAL SILO (Hg) Meal & Hg Removed Raw Meal, Hg Inventory Falls Raw Meal, HgInventory Increase Clinker Raw Mill Raw Materials Hg 120 lb Hg/yr in Limestone, Sand, Fly Ash, Mill Scale
600 tons per day (TPD) WTE Process and Controls 2 - 20 µg/dscm 4 to 40 lb/yr All have spray dryer/absorbers and fabric filter baghouses 600 TPDMunicipal Waste February 10, 2009 | 11
Activated Carbon Injection (ACI) < 5 µg/dscm < 10 lb/yr ACI means greater certaintyof Continuous Control Fabric Filter Bottom Ash Fly Ash Containing Reacted Lime, Spent Carbon, Hg
12,000 But are Underlying Tests Truly Representative? Highly Variable Inputs make Snapshot In-stack Test Unreliable Estimators of Maximum Emissions. February 10, 2009 | 14
Hg-CEMS WTE Tests were Short-Term In-Stack Tests Sorbent Traps and Speciation at Cement, Power Hg-CEMS are in Place at JEA Northside Soon American Cement, Hillsborough WTE Unit 4 Diagnostic Hg-CEMS at CEMEX Brooksville South Used for Years at WTE and Cement in Germany Incorporate Industry/Instrument-Specific Manuals
Next Steps Reports for One Power Plant and Cement Kiln EPA Informational Collection Requests (ICR) Industrial Boilers, Coal Power, Fertilizer Look at Secondary Steel Examine Reliability of New Hg-CEMS Comments to EPA on Hg Rulemaking