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Subpart K—Ferroalloy Production

§ 98.110 Definition of the source category.

The ferroalloy production source category consists of any 

facility that uses pyrometallurgical techniques to produce any 

of the following metals: ferrochromium, ferromanganese, 

ferromolybdenum, ferronickel, ferrosilicon, ferrotitanium, 

ferrotungsten, ferrovanadium, silicomanganese, or silicon metal.

§ 98.111 Reporting threshold.

You must report GHG emissions under this subpart if your 

facility contains a ferroalloy production process and the 

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

§ 98.112 GHGs to report.

You must report:

(a) Process CO2 emissions from each electric arc furnace

(EAF) used for the production of any ferroalloy listed in 

§98.110, and process CH4 emissions from each EAF that is used for 

the production of any ferroalloy listed in Table K–1 to subpart 

K.

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

combustion unit following the requirements of subpart C of this 

part. You must report these emissions under subpart C of this 

part (General Stationary Fuel Combustion Sources).

§ 98.113 Calculating GHG emissions.
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You must calculate and report the annual process CO2

emissions from each EAF not subject to paragraph (c) of this 

section using the procedures in either paragraph (a) or (b) of 

this section. For each EAF also subject to annual process CH4

emissions reporting, you must also calculate and report the 

annual process CH4 emissions from the EAF using the procedures in 

paragraph (d) of this section.

(a) Calculate and report under this subpart the process CO2

emissions by operating and maintaining CEMS 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 

(General Stationary Fuel Combustion Sources).

(b) Calculate and report under this subpart the annual 

process CO2 emissions using the procedure in either paragraph 

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

(1) Calculate and report under this subpart the annual 

process CO2 emissions from EAFs by operating and maintaining a 

CEMS according to the Tier 4 Calculation Methodology specified 

in §98.33(a)(4) and the applicable requirements for Tier 4 in 

subpart C of this part (General Stationary Fuel Combustion 

Sources).

(2) Calculate and report under this subpart the annual 

process CO2 emissions from the EAFs using the carbon mass balance 
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procedure specified in paragraphs (b)(2)(i) and (b)(2)(ii) of 

this section.

(i) For each EAF, determine the annual mass of carbon in 

each carbon-containing input and output material for the EAF and 

estimate annual process CO2 emissions from the EAF using Equation 

K–1 of this section. Carbon-containing input materials include 

carbon electrodes and carbonaceous reducing agents. If you 

document that a specific input or output material contributes 

less than 1 percent of the total carbon into or out of the 

process, you do not have to include the material in your 

calculation using Equation K–1 of this section.

Where:

ECO2 = Annual process CO2 emissions from an individual 

EAF (metric tons).

44/12 = Ratio of molecular weights, CO2 to carbon.
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2000/2205 = Conversion factor to convert tons to metric 

tons.

Mreducing agenti = Annual mass of reducing agent i fed, 

charged, or otherwise introduced into the EAF (tons).

Creducing agenti = Carbon content in reducing agent i (percent 

by weight, expressed as a decimal fraction).

Melectrodem = Annual mass of carbon electrode m consumed in 

the EAF (tons).

Celectrodem = Carbon content of the carbon electrode m 

(percent by weight, expressed as a decimal fraction).

Moreh = Annual mass of ore h charged to the EAF 

(tons).

Coreh = Carbon content in ore h (percent by weight, 

expressed as a decimal fraction).

Mfluxj = Annual mass of flux material j fed, charged, 

or otherwise introduced into the EAF to facilitate 

slag formation (tons).

Cfluxj = Carbon content in flux material j (percent by 

weight, expressed as a decimal fraction).

Mproductk = Annual mass of alloy product k tapped from EAF 

(tons).

Cproductk = Carbon content in alloy product k. (percent by 

weight, expressed as a decimal fraction).

Mnon-product outgoingl = Annual mass of non-product 

outgoing material l removed from 

EAF (tons).

Cnon-product outgoingl = Carbon content in non-product 

outgoing material l (percent by 

weight, expressed as a decimal 

fraction).

(ii) Determine the combined annual process CO2 emissions 

from the EAFs at your facility using Equation K–2 of this 

section.
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Where:

CO2 = Annual process CO2 emissions from EAFs at 

facility used for the production of any ferroalloy 

listed in §98.110 (metric tons).

ECO2 k = Annual process CO2 emissions calculated from 

EAF k calculated using Equation K–1 of this section 

(metric tons).

k = Total number of EAFs at facility used for the 

production of any ferroalloy listed in §98.110.

(c) If GHG emissions from an EAF 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.

(d) For the EAFs at your facility used for the production 

of any ferroalloy listed in Table K–1 of this subpart, you must 

calculate and report the annual CH4 emissions using the procedure 

specified in paragraphs (d)(1) and (2) of this section.

(1) For each EAF, determine the annual CH4 emissions using 

Equation K–3 of this section.
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Where:

ECH4= Annual process CH4 emissions from an individual 

EAF (metric tons).

Mproducti = Annual mass of alloy product i produced in the 

EAF (tons).

2/2205 = Conversion factor to convert kg CH4/ton of 

product to metric tons CH4.

EFproducti = CH4 emission factor for alloy product i from 

Table K–1 in this subpart (kg of CH4 emissions 

per metric ton of alloy product i).

(2) Determine the combined process CH4 emissions from the 

EAFs at your facility using Equation K–4 of this section:

Where:

CH4 = Annual process CH4 emissions from EAFs at facility 

used for the production of ferroalloys listed in 

Table K–1 of this subpart (metric tons).

ECH4 j = Annual process CH4 emissions from EAF j calculated 

using Equation K–3 of this section (metric tons).

j = Total number of EAFs at facility used for the 

production of ferroalloys listed in Table K–1 of 

this subpart.

§ 98.114 Monitoring and QA/QC requirements.

If you determine annual process CO2 emissions using the 

carbon mass balance procedure in §98.113(b)(2), you must meet 

the requirements specified in paragraphs (a) and (b) of this 

section.
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(a) Determine the annual mass for each material used for 

the calculations of annual process CO2 emissions using Equation 

K–1 of this subpart by summing the monthly mass for the material 

determined for each month of the calendar year. The monthly mass 

may be determined using plant instruments used for accounting 

purposes, including either direct measurement of the quantity of 

the material placed in the unit or by calculations using process 

operating information.

(b) For each material identified in paragraph (a) of this 

section, you must determine the average carbon content of the 

material consumed, used, or produced in the calendar year using 

the methods specified in either paragraph (b)(1) or (b)(2) of 

this section. If you document that a specific process input or 

output contributes less than one percent of the total mass of 

carbon into or out of the process, you do not have to determine 

the monthly mass or annual carbon content of that input or 

output.

(1) Information provided by your material supplier.

(2) Collecting and analyzing at least three representative 

samples of the material inputs and outputs each year. The carbon 

content of the material must be analyzed at least annually using 

the standard methods (and their QA/QC procedures) specified in 

paragraphs (b)(2)(i) through (b)(2)(iii) of this section, as 

applicable.
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(i) ASTM E1941–04, Standard Test Method for Determination 

of Carbon in Refractory and Reactive Metals and Their Alloys 

(incorporated by reference, see §98.7) for analysis of metal ore 

and alloy product.

(ii) 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), for 

analysis of carbonaceous reducing agents and carbon electrodes.

(iii) ASTM C25–06, Standard Test Methods for Chemical 

Analysis of Limestone, Quicklime, and Hydrated Lime 

(incorporated by reference, see §98.7) for analysis of flux 

materials such as limestone or dolomite.

§ 98.115 Procedures for estimating missing data.

A complete record of all measured parameters used in the 

GHG emissions calculations in §98.113 is required. 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 in the paragraphs 

(a) and (b) of this section. You must document and keep records 

of the procedures used for all such estimates.

(a) If you determine CO2 emissions for the EAFs at your 

facility using the carbon mass balance procedure in §98.113(b), 

100 percent data availability is required for the carbon content 

of the input and output materials. You must repeat the test for 
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average carbon contents of inputs according to the procedures in 

§98.114(b) if data are missing.

(b) For missing records of the monthly mass of carboncontaining inputs and outputs, the substitute data value must be 

based on the best available estimate of the mass of the inputs 

and outputs from on all available process data or data used for 

accounting purposes, such as purchase records.

(c) If you are required to calculate CH4 emissions for an 

EAF at your facility as specified in §98.113(d), the estimate is 

based an annual quantity of certain alloy products, so 100 

percent data availability is required.

§ 98.116 Data reporting requirements.

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

annual report must contain the information specified in 

paragraphs (a) through (e) of this section, as applicable:

(a) Annual facility ferroalloy product production capacity 

(tons).

(b) Annual production for each ferroalloy product 

identified in §98.110, from each EAF (tons).

(c) Total number of EAFs at facility used for production of 

ferroalloy products.

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

must report under this subpart the relevant information required 

by §98.36 for the Tier 4 Calculation Methodology and the 
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following information specified in paragraphs (d)(1) through 

(d)(3) of this section.

(1) Annual process CO2 emissions (in metric tons) from each 

EAF used for the production of any ferroalloy product identified 

in §98.110.

(2) Annual process CH4 emissions (in metric tons) from each 

EAF used for the production of any ferroalloy listed in Table K–

1 of this subpart (metric tons).

(3) Identification number of each EAF.

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

and the carbon mass balance procedure is used to determine CO2

emissions according to the requirements in §98.113(b), then you 

must report the following information specified in paragraphs 

(e)(1) through (e)(7) of this section.

(1) Annual process CO2 emissions (in metric tons) from each 

EAF used for the production of any ferroalloy identified in 

§98.110 (metric tons).

(2) Annual process CH4 emissions (in metric tons) from each 

EAF used for the production of any ferroalloy listed in Table K–

1 of this subpart.

(3) Identification number for each material.

(4) Annual material quantity for each material included for 

the calculation of annual process CO2 emissions for each EAF.
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(5) Annual average of the carbon content determinations for 

each material included for the calculation of annual process CO2

emissions for each EAF (percent by weight, expressed as a 

decimal fraction).

(6) List the method used for the determination of carbon 

content for each material reported in paragraph (e)(5) of this 

section (e.g., supplier provided information, analyses of 

representative samples you collected).

(7) If you use the missing data procedures in §98.115(b), 

you must report how monthly mass of carbon-containing inputs and 

outputs with missing data was determined and the number of 

months the missing data procedures were used.

§ 98.117 Records that must be retained.

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

retain the records specified in paragraphs (a) through (d) of 

this section for each EAF, as applicable.

(a) If a CEMS is used to measure CO2 emissions according to 

the requirements in §98.113(a), then you must retain under this 

subpart the records required for the Tier 4 Calculation 

Methodology in §98.37 and the information specified in 

paragraphs (a)(1) through (a)(3) of this section.

(1) Monthly EAF production quantity for each ferroalloy 

product (tons).

(2) Number of EAF operating hours each month.
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(3) Number of EAF operating hours in a calendar year.

(b) If the carbon mass balance procedure is used to 

determine CO2 emissions according to the requirements in 

§98.113(b)(2), then you must retain records for the information 

specified in paragraphs (b)(1) through (b)(5) of this section.

(1) Monthly EAF production quantity for each ferroalloy 

product (tons).

(2) Number of EAF operating hours each month.

(3) Number of EAF operating hours in a calendar year.

(4) Monthly material quantity consumed, used, or produced 

for each material included for the calculations of annual 

process CO2 emissions (tons).

(5) Average carbon content determined and records of the 

supplier provided information or analyses used for the 

determination for each material included for the calculations of 

annual process CO2 emissions.

(c) You must keep records that include a detailed 

explanation of how company records of measurements are used to 

estimate the carbon input and output to each EAF, including 

documentation of specific input or output materials excluded 

from Equation K–1 of this subpart that contribute less than 1 

percent of the total carbon into or out of the process. You also 

must document the procedures used to ensure the accuracy of the 

measurements of materials fed, charged, or placed in an EAF 
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including, but not limited to, calibration of weighing equipment 

and other measurement devices. The estimated accuracy of 

measurements made with these devices must also be recorded, and 

the technical basis for these estimates must be provided.

(d) If you are required to calculate CH4 emissions for the 

EAF as specified in §98.113(d), you must maintain records of the 

total amount of each alloy product produced for the specified 

reporting period, and the appropriate alloy-product specific 

emission factor used to calculate the CH4 emissions.

§ 98.118 Definitions.

All terms used of this subpart have the same meaning given 

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

Table K–1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4

Emission Factors

Alloy product produced 

in EAF

CH4 emission factor

(kg CH4 per metric ton product)

EAF Operation

Batchcharging

Sprinklecharginga

Sprinklecharging and

>750 °Cb

Silicon metal 1.5 1.2 0.7

Ferrosilicon 90% 1.4 1.1 0.6

Ferrosilicon 75% 1.3 1.0 0.5

Ferrosilicon 65% 1.3 1.0 0.5

aSprinkle-charging is charging intermittently every minute.

bTemperature measured in off-gas channel downstream of the furnace hood.