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Subpart BB—Silicon Carbide Production

§ 98.280 Definition of the source category.

Silicon carbide production includes any process that 

produces silicon carbide for abrasive purposes.

§ 98.281 Reporting threshold.

You must report GHG emissions under this subpart if your 

facility contains a silicon carbide production process and the 

facility meets the requirements of either §98.2(a)(1) or (a)(2).

§ 98.282 GHGs to report.

You must report:

(a) CO2 process emissions from all silicon carbide process 

units or furnaces combined.

(b) CO2, CH4, and N2O emissions from each stationary 

combustion unit. You must report these emissions under subpart C 

of this part (General Stationary Fuel Combustion Sources) by 

following the requirements of subpart C.

§ 98.283 Calculating GHG emissions.

You must calculate and report the combined annual process 

CO2 emissions from all silicon carbide process units and

production furnaces using the procedures in either paragraph (a) 

or (b) of this section. (a) Calculate and report under this 

subpart the combined annual process CO2 emissions by operating 

and maintaining CEMS according to the Tier 4 Calculation 

Methodology specified in §98.33(a)(4) and all associated 
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requirements for Tier 4 in subpart C of this part (General 

Stationary Fuel Combustion Sources).

(b) Calculate and report under this subpart the combined 

annual process CO2 emissions using the procedures in paragraphs 

(b)(1) and (b)(2) of this section.

(1) Use Equation BB–1 of this section to calculate the 

facility-specific emissions factor for determining CO2 emissions. 

The carbon content must be measured monthly and used to 

calculate a monthly CO2 emissions factor:

Where:

EFCO2,n = CO2 emissions factor in month n (metric tons 

CO2/metric ton of petroleum coke consumed).

0.65 = Adjustment factor for the amount of carbon in 

silicon carbide product (assuming 35 percent 

of carbon input is in the carbide product).

CCFn = Carbon content factor for petroleum coke 

consumed in month n from the supplier or as 

measured by the applicable method incorporated 

by reference in §98.7 according to §98.284(c) 

(percent by weight expressed as a decimal 

fraction).

44/12 = Ratio of molecular weights, CO2 to carbon.

(2) Calculate annual CO2 process emissions from the silicon

carbide production facility according to Equation BB-2 of this 

section:
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Where:

CO2 = Annual CO2 emissions from silicon carbide 

production facility (metric tons CO2).

Tn = Petroleum coke consumption in calendar month n 

(tons).

EFCO2,n = CO2 emissions factor from month n (calculated 

in Equation BB–1 of this section).

2000/2205 = Conversion factor to convert tons to metric 

tons.

n = Number of month.

(c) If GHG emissions from a silicon carbide production 

furnace or process unit are vented through the same stack as any 

combustion unit or process equipment that reports CO2 emissions 

using a CEMS that complies with the Tier 4 Calculation 

Methodology in subpart C of this part (General Stationary Fuel 

Combustion Sources), then the calculation methodology in 

paragraph (b) of this section shall not be used to calculate 

process emissions. The owner or operator shall report under this 

subpart the combined stack emissions according to the Tier 4 

Calculation Methodology in §98.33(a)(4) and all associated 

requirements for Tier 4 in subpart C of this part.

§ 98.284 Monitoring and QA/QC requirements.

(a) You must measure your consumption of petroleum coke 

using plant instruments used for accounting purposes including 

direct measurement weighing the petroleum coke fed into your 

process (by belt scales or a similar device) or through the use 

of purchase records.
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(b) You must document the procedures used to ensure the 

accuracy of monthly petroleum coke consumption measurements.

(c) For CO2 process emissions, you must determine the 

monthly carbon content of the petroleum coke using reports from 

the supplier. Alternatively, facilities can measure monthly 

carbon contents of the petroleum coke using ASTM D3176–89 

(Reapproved 2002) Standard Practice for Ultimate Analysis of 

Coal and Coke (incorporated by reference, see §98.7) and ASTM 

D5373–08 Standard Test Methods for Instrumental Determination of 

Carbon, Hydrogen, and Nitrogen in Laboratory Samples of Coal 

(incorporated by reference, see §98.7).

(d) For quality assurance and quality control of the 

supplier data, you must conduct an annual measurement of the 

carbon content of the petroleum coke using ASTM D3176–89 and 

ASTM D5373–08 Standard Test Methods for Instrumental 

Determination of Carbon, Hydrogen, and Nitrogen in Laboratory 

Samples of Coal (incorporated by reference, see §98.7).

§ 98.285 Procedures for estimating missing data.

For the petroleum coke input procedure in §98.283(b), a 

complete record of all measured parameters used in the GHG 

emissions calculations is required (e.g., carbon content values, 

etc.). Therefore, whenever a quality-assured value of a required 

parameter is unavailable, a substitute data value for the 

missing parameter shall be used in the calculations as specified 
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in the paragraphs (a) and (b) of this section. You must document 

and keep records of the procedures used for all such estimates.

(a) For each missing value of the monthly carbon content of 

petroleum coke, the substitute data value shall be the 

arithmetic average of the quality-assured values of carbon 

contents immediately preceding and immediately following the 

missing data incident. If no quality-assured data on carbon 

contents are available prior to the missing data incident, the 

substitute data value shall be the first quality-assured value 

for carbon contents obtained after the missing data period.

(b) For each missing value of the monthly petroleum coke 

consumption, the substitute data value shall be the best 

available estimate of the petroleum coke consumption based on

all available process data or information used for accounting 

purposes (such as purchase records).

§ 98.286 Data reporting requirements.

In addition to the information required by §98.3(c), each 

annual report must contain the information specified in 

paragraphs (a) or (b) of this section, as applicable for each 

silicon carbide production facility.

(a) If a CEMS is used to measure process CO2 emissions, you 

must report under this subpart the relevant information required 

for the Tier 4 Calculation Methodology in §98.36 and the 

information listed in this paragraph (a):
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(1) Annual consumption of petroleum coke (tons).

(2) Annual production of silicon carbide (tons).

(3) Annual production capacity of silicon carbide (tons).

(b) If a CEMS is not used to measure process CO2 emissions, 

you must report the information in paragraph (b)(1) through 

(b)(8) of this section for all silicon carbide process units or 

production furnaces combined:

(1) Monthly consumption of petroleum coke (tons).

(2) Annual production of silicon carbide (tons).

(3) Annual production capacity of silicon carbide (tons).

(4) Carbon content factor of petroleum coke from the 

supplier or as measured by the applicable method in §98.284(c) 

for each month (percent by weight expressed as a decimal 

fraction).

(5) Whether carbon content of the petroleum coke is based 

on reports from the supplier or through self measurement using 

applicable ASTM standard method.

(6) CO2 emissions factor calculated for each month (metric 

tons CO2/metric ton of petroleum coke consumed).

(7) Sampling analysis results for carbon content of 

consumed petroleum coke as determined for QA/QC of supplier data 

under §98.284(d) (percent by weight expressed as a decimal 

fraction).
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(8) Number of times in the reporting year that missing data 

procedures were followed to measure the carbon contents of 

petroleum coke (number of months) and petroleum coke consumption 

(number of months).

§ 98.287 Records that must be retained.

In addition to the records required by §98.3(g), you must 

retain the records specified in paragraphs (a) and (b) of this 

section for each silicon carbide production facility.

(a) If a CEMS is used to measure CO2 emissions, you must 

retain under this subpart the records required for the Tier 4 

Calculation Methodology in §98.37 and the information listed in 

this paragraph (a):

(1) Records of all petroleum coke purchases.

(2) Annual operating hours.

(b) If a CEMS is not used to measure emissions, you must 

retain records for the information listed in this paragraph (b):

(1) Records of all analyses and calculations conducted for 

reported data listed in §98.286(b).

(2) Records of all petroleum coke purchases.

(3) Annual operating hours.

§ 98.288 Definitions.

All terms used in this subpart have the same meaning given 

in the Clean Air Act and subpart A of this part.