Large Unit vs. Small Unit RetrofitConsiderations for Multi-PollutantEmission Control

William T. Stark

APPA Engineering & Operations Technical ConferenceMarch 8, 2004

Basis of Presentation

1600 MW, PRB coal-fired, base load plant 100 MW, Illinois Basin, bituminous

coal-fired, intermediate load plant Individual units ranging in size from

10 MW to 550 MW pulverized coal-fired

Regulatory Considerations

8-hr Ozone Standard

PM2.5 Standard

Regional Haze Rule

Utility Boiler MACT

Industrial Boiler MACT

Clear Skies Act of 2003

Clean Power Act of 2003

Clean Air Planning Act

Interstate Air Quality Rule

Utility Boiler MACT

Option 1 Emission standards by coal rank Averaging allowed for facility Incorporates Ontario Hydro Method

and continuous sampling (Method 324)

Option 2 Cap-and-Trade program

Industrial Boiler MACT

Applies to coal-fired units < 25 MW Large units (>10 MMBtu/hr) must

meet PM or metals standard, as well as HCl and Hg limits

Proposal contains initial testing and compliance requirements

Interstate Air Quality Rule

General Affects 29 eastern states and DC Proposal requires upwind states to

revise SIPs to include control measures to reduce emissions of NOx and SO2

Options are to participate in cap-and-trade program or comply with state budget set by EPA

Interstate Air Quality Rule

Proposed Caps and Allocations SO2 allocations made in proportion to

Title IV allowances. Overall a 50% reduction for 2010 and a 65% reduction for 2015

NOx allocations based on highest year of heat input for state during 1999-2002

Compliance on an annual basis

Wet Scrubber Capital Costs

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Unit Size, MW

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Wet Scrubber Capital Costs*Line Drawn to Show Trend

Wet Scrubber O&M Costs (1% S Coal)

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Spray Dryer Absorber Capital Costs

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SDA Capital Cost*Line Drawn to Show Trend

Spray Dryer Absorber O&M Costs

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SCR Capital Costs

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SCR Capital Cost*Line Drawn to Show Trend

SCR O&M Costs

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Mercury Control

Concurrent reductions resulting from control of SO2 and/or PM

Sorbent Injection

Sorbent injection systems cost in the vicinity of $1.5 – 3.0 million

Depending on removal requirements, a baghouse may be required in addition to the sorbent injection system

Baghouse Capital Costs

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Baghouse Capital Cost*Line Drawn to Show Trend

Emission Control Scenarios for Consideration

Emission control for each individual unit Emission controls for combined flue gas

streams from units Use of high efficiency controls on larger

units with less control on smaller units Use of multi-pollutant control

technologies

Summary Comments

Compliance could be costly Items to consider:

Capacity factor Load shifting Fuel switching Shutdown of units