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David Read Cement Subproject Manager Bureau of Air Regulation

Cement Mercury Subproject. David Read Cement Subproject Manager Bureau of Air Regulation. Florida Cement Industry. 10,000,000 tons per year clinker Ten cement kilns Demand is down Five in operation Two are temporarily down Three at/near startup. Suwannee American. Vulcan. American.

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David Read Cement Subproject Manager Bureau of Air Regulation

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  1. Cement Mercury Subproject David Read Cement Subproject ManagerBureau of Air Regulation

  2. Florida Cement Industry 10,000,000 tons per year clinker Ten cement kilns Demand is down Five in operation Two are temporarily down Three at/near startup Suwannee American Vulcan American CEMEX N. Brooksville CEMEX S. Brooksville Titan America CEMEX Miami

  3. Fuel and Materials Hg – Plant AConcentrations in parts per billion (ppb)

  4. Fuel and Materials Hg – Plant AContribution to total emissions in percent (%)

  5. EPA and Florida Kiln Emission Estimatesin pounds (lb) of Hg per million tons of clinker Highest ~ 3,300 lb/million tons clinker 40 Best 12% by EPA ranking Lowest ~ 10 lb/million tons clinker

  6. Raw Mill Off – Hg Emitted Raw Mill On – Most Hg Captured, Stored LOTS Little Hg out Filter LEGEND Gas Solid Preheater Exhaust Filter Dust Separators Preheater Feed FuelHg in Meal & Hg Stored CoalHg in RAW MEAL SILO (Hg) Meal & Hg Removed ClinkerNo Hg out Raw Mill (to Cement Mill) Hg in (from Raw Mix)

  7. Hg Control Options • Limit high carbon coal ash, raw materials/fuels Hg • Add-on control equipment prior to stack • Baghouse, activated carbon (Norcem Brevik and Ash Grove Durkee, Oregon) • Wet Scrubber (such as for SO2 in TXI Midlothian, Holcim Holly Hill) • Heat and return filter dust, recover Hg in activated carbon • Much smaller gas volume than end-of-process controls (F.L. Smidth offers) • Heat problem fuels/material, recover Hg in activated carbon • Also much smaller volume (F.L. Smidth describes in patent) • Filter dust shuttling to cement product • Typically practiced in some European countries (allowed in Florida?)

  8. Filter Dust Shuttling – Mill Off Hg Removed by Scrubber Problem Raw Material/Fuel Treatment Hg Removal by Activated Carbon Filter Dust Treatment, Return Some Hg out Scrubber Filter LEGEND Gas Solid Hg in Most (Filter Dust) Some Hg out Hg out Mercury Hg out Hg in (to Cement Mill) Plant (Alternate Hg Mercury Material/Fuel) Removed Plant (Filter Dust) Some Hg in Hg (fuel) Removed RAW MEAL SILO Hg in (coal) (Hg Removed) (Hg Stored) No Hg out (to Cement Mill) Hg in (from Raw Mix)

  9. Comparison of Florida Kilns with Best 12% at 25, 50, and 75% reduction from present estimates

  10. Florida Cement Industry Summary • Florida kilns emit ~ 100 lb Hg/million tons clinker • At full capacity emissions will be ~ 1,000 lb Hg/year • A well-controlled coal power unit emits < 20 lb Hg/year • EPA will propose draft limit by March 31, 2009 • May need significant reductions to achieve EPA limit • Start with more careful materials and fuel selection • Avoid high carbon fly ash (abated power plant emissions) • Shuttle filter dust to product to extent cement meets specs • Treat problem alternative fuels/materials • Only then get to end-of-process add-on controls

  11. Additional Thoughts Need better data at some existing kilns Material testing, sorbent traps, Hg-CEMS Total Maximum Daily Load (TMDL) driver May require limits beyond EPA MACT* We ought to try out dust shuttling first We will visit FDOT** to see if allowed * Maximum Achievable Control Technology ** Florida Department of Transportation

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