Appendix P 

BART Model Plant Criteria with PM 
BART Model Pl

Criteria with P

Jim Boylan

Georgia Department of Natural 

VISTAS BART Group

August 29, 2006
Model Plant Crite

•

E < 500 tons & 

d > 50 km

•

E < 1000 tons & 

d > 100 km

–

E = potential emissions of “SO2 or NOx”

–

d is the distance to closest Class I a

• In the Southeastern U.S., SO2 (sulf

has larger impact on light extinctio(nitrate).

– Conservative approach would be t

SO2 emissions

• What about adding PM to the mo

criteria?
– f(rh) ranges from 2.3 - 4.7 with an avera

in the VISTAS states

– Average contributions to bext (Mm-1) 

• Sulfate = 3*f(RH)*[SO4] = 9.6*[SO4] 

– [SO4] assumed to be in form of (NH

• Nitrate = 3*f(RH)*[NO3] = 9.6*[NO3] 

– [NO3] assumed to be in form of NH

• Elemental Carbon = 10*[EC]• Organic Carbon = 4*[ORG]• Soils = 1*[Soils]• Coarse Mass = 0.6*[PMC]

– Conservative approach is to assume al

• [PMC]=0

Light Extinction
SO2 vs. PM Emissi

• SO2 does not impact light extincti• Only a fraction of the SO2 become• How much?

– Function of SO2 to SO4 conversio– Function of distance downwind– Function of wind speed

• 100% of primary PM becomes PM

– Speciation of PM will impact ligh
Conversion Facto

• Calculate a “PM factor” to relate p

to secondary sulfate PM from SO2

– e.g.,

E = SO2+NOx+10*PM

• Lower SO2 to SO4 conversion resu

PM factor

– Higher PM factor is more conserv

• Conversion of 1 ton SO2 (MW=64) 

produce 2.0625 tons (NH

4

)

2SO

4 (M
Example

• Assume all primary PM is sulfate 

dry deposition

• 100 tons SO2 with 5% conversion 

– 100 tons SO2 * 5% conversion 

= 5 tons * 2.0625 = 10.3125 tons SO4 PM produced 

– 100 tons PM = 100 tons PM 

• E = SO2 + NOx + (100/10.3125)*

= SO2 + NOx + 9.7*PM

= SO2 + NOx + 10*PM
Mean SO2 Conversion Rate 

Plant Plume by Season and T

0

0.5

1

1.5

2

2.5

3

5:00 7:00 9:00 11:00 13:00 15:00 17

Conversion Rate (%)

Fall-Wint

0

0.5

1

1.5

2

2.5

3

5:00 7:00 9:00 11:00 13:00 15:00 17

Time Midpoint

Conversion Rate (%)

Fall-Wint

0

0.5

1

1.5

2

2.5

3

5:00 7:00 9:00 11:00 13:00 15:00 17

Conversion Rate (%)

Fall-Wint

0

0.5

1

1.5

2

2.5

3

5:00 7:00 9:00 11:00 13:00 15:00 17

Time Midpoint

Conversion Rate (%)

Fall-Wint
Assumptions

• Distance downwind = 50 km (31 m

– Model plant criteria distance

• SO2 to SO4 conversion rate = 1.5% 

– Max. sulfate production is during – Lower conversion rate produces h

Factor

• Wind speed = 5 m/s (11.2 mph)

– Higher wind speeds produce high– Max. sulfate production occurs at 

• Likely < 5 m/s

–

t = 31 miles/11.2 mph = 2.77 hour
PM Factor

• SO2 conversion = 1.5% * 2.77 hour

– 100 tons SO2 * 4.15% conversion

= 4.15 tons * 2.0625 = 8.56 tons SO4 PM produced 

– 100 tons PM = 100 tons PM 

• E = SO2 + NOx + (100/8.56)*PM 

= SO2 + NOx + 11.7*PM 

= SO2 + NOx + 12*PM 

– Assumes all primary PM is sulfat
PM Speciation

• Not all primary PM will be sulfate• Scale components of PM by ratio o

extinction coefficient to average suextinction coefficient (9.6)

• E = SO2 + NOx + 12*PM*[(%SO4)

(%NO3)*(9.6/9.6)+(%EC)*(10/9.6(%OC)*(4/9.6)+(%Soils)*(1.0/9.6)

• E = SO2 + NOx + 12*PM*[(%SO4)

1.04*(%EC)+0.42*(%OC)+0.1*(%So
International Paper - Sa

• SO2=0.0 tons, NOx=0.0 tons, PM=• Distance to nearest Class I area = 

– Need 

E < 500 tons to be exempt

• Assume 100% primary PM is sulfa

–

E = 12 * 51.4 = 616.8 tons (> 500 

Î 

• PM Speciation from SMOKE prof

– SO4=20.40%, NO3=0.37%, EC=2.6

OC=35.69%, Soils=40.91%

–

E = 12 * 51.4 * [(0.204) + (0.0037) + 

+ 0.42*(0.3569) + 0.1

–

E = 263.0 tons (< 500 

Î EXEMPT