Table 5.  Coal Plant Configurations, Emissions Modification Factors, and Mercury Control Options

Plant Configuration

Emissions Modification Factors (Fraction Remaining) by Coal Rank

Hg Control Option Available

SO2 Control

Particulate

SCR

Combined

SO2 Control

Particulate Control

SCR

Subbituminous/ Other

Bituminous

All Coal Ranks

All Coal Ranks

Subbituminous/ Other

Bituminous

None

BH

NA

1.00

1.00

0.31

1.00

0.288

0.288

Injection

None

BH

NA

1.00

1.00

0.31

1.00

0.288

0.288

Injection/SC

Wet

BH

No

0.81

0.34

0.31

1.00

0.234

0.098

Injection

Wet

BH

No

0.81

0.34

0.31

1.00

0.234

0.098

Injection/SC

Wet

BH

Yes

0.81

0.34

0.31

  0.65a

0.152

0.064

Injection

Wet

BH

Yes

0.81

0.34

0.31

  0.65a

0.152

0.064

Injection/SC

Dry

BH

NA

0.61

0.61

1.00

1.00

0.567

0.567

Injection

Dry

BH

NA

0.61

0.61

1.00

1.00

0.567

0.567

Injection/SC

None

CSE

NA

1.00

1.00

0.69

1.00

0.642

0.642

Injection

None

CSE

NA

1.00

1.00

0.69

1.00

0.642

0.642

Injection/FF

None

CSE

NA

1.00

1.00

0.69

1.00

0.642

0.642

Injection/SC/FF

Wet

CSE

No

0.81

0.34

0.69

1.00

0.520

0.218

Injection

Wet

CSE

No

0.81

0.34

0.69

1.00

0.520

0.218

Injection/FF

Wet

CSE

No

0.81

0.34

0.69

1.00

0.520

0.218

Injection/SC/FF

Wet

CSE

Yes

0.81

0.34

0.69

  0.65a

0.338

0.142

Injection

Wet

CSE

Yes

0.81

0.34

0.69

  0.65a

0.338

0.142

Injection/FF

Wet

CSE

Yes

0.81

0.34

0.69

  0.65a

0.338

0.142

Injection/SC/FF

Dry

CSE

NA

0.61

0.61

  1.00b

1.00

0.567

0.567

Injection

Dry

CSE

NA

0.61

0.61

  1.00b

1.00

0.567

0.567

Injection/SC/FF

Dry

CSE

NA

0.61

0.61

  1.00b

1.00

0.567

0.567

Injection/FF

None

HSE/Other

NA

1.00

1.00

1.00

1.00

0.930

0.930

None

None

HSE/Other

NA

1.00

1.00

1.00

1.00

0.930

0.930

Injection/FF

None

HSE/Other

NA

1.00

1.00

1.00

1.00

0.930

0.930

Injection/SC/FF

Wet

HSE/Other

No

0.81

0.34

1.00

1.00

0.753

0.316

None

Wet

HSE/Other

No

0.81

0.34

1.00

1.00

0.753

0.316

Injection/FF

Wet

HSE/Other

No

0.81

0.34

1.00

1.00

0.753

0.316

Injection/SC/FF

Wet

HSE/Other

Yes

0.81

0.34

1.00

  0.65a

0.490

0.206

None

Wet

HSE/Other

Yes

0.81

0.34

1.00

  0.65a

0.490

0.206

Injection/FF

Wet

HSE/Other

Yes

0.81

0.34

1.00

  0.65a

0.490

0.206

Injection/SC/FF

Dry

HSE/Other

NA

0.61

0.61

1.00

1.00

0.567

0.567

None

Dry

HSE/Other

NA

0.61

0.61

1.00

1.00

0.567

0.567

Injection/FF

Dry

HSE/Other

NA

0.61

0.61

1.00

1.00

0.567

0.567

Injection/SC/FF

aSCRs are assumed to reduce Hg emissions only when combined with a wet scrubber designed to remove SO2.

bCSEs do not remove additional Hg when combined with a dry scrubber.

Notes: BH = bag house, CSE = cold side electrostatic precipitator, FF = fabric filter, HSE = hot side electrostatic precipitator, SC = spray cooler, SCR = selective catalytic reduction. NA = not applicable. An emissions modification factor (EMF) of 0.93 is assumed for all boiler configurations and is incorporated in the derivation of the combined EMFs.

Source: Energy Information Administration, Office of Integrated Analysis and Forecasting.

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