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**Subpart G**

**— Ammonia Manufacturing**  **§98.70 Definition**  **of source category.** The ammonia manufacturing source category comprises the process units listed in paragraphs (a) and (b) of this section. (a) Ammonia manufacturing processes in which ammonia is manufactured from a fossil

based feedstock produced via steam reforming of a hydrocarbon. (b) Ammonia manufacturing processes in which ammonia is manufactured through the gasification of solid and liquid raw material. **§98.71 Reporting threshold.**  You must report GHG emissions under this subpart if your facility cont ains an ammonia manufacturing process and the facility meets the requirements of either §98.2(a)(1) or (2). **§98.72 GHGs to report.**  You must report: (a) CO 2 process emissions from steam reforming of a hydrocarbon or the gasification of solid and liquid raw material, reported for each ammonia manufacturing process unit following the requirements of this subpart (CO 2 process emissions reported under this subpart may include CO 2 that is later consumed on site for urea production, and therefore is not released to the ambient air from the ammonia manufacturing process unit). (b) CO 2 , CH 4 , and N 2 O emissions from each stationary fuel combustion unit. You must report these emissions under subpart C of this part (General Stationary Fuel Combustion Sources), b y followi ng the requirements of subpart C, except that for ammonia manufacturing processes subpart C does not apply to any CO 2 resulting from combustion of the waste recycle stream (commonl y referred to as the purge gas stream).Page 2 of 10

(c) CO 2 emissions collected and tran sferred off site under subpart PP of this part (Suppliers of CO 2 ), following the requirements of subpart PP. **§98.73 Calculating GHG emissions.** You must calculate and report the annual process CO 2 emissions from each ammonia manufacturing process unit using the procedures in either paragraph (a) or (b) of this section. (a) Calculate and report under this subpart the process CO 2 emissions by operating and maintaining CEMS according to the Tier 4 Calculation Methodology specified in §98.33(a)(4) and all associ ated requirements for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources). (b) Calculate and report under this subpart process CO 2 emissions using the procedures in paragraphs (b)(1) through (b)(5) of this section for gaseous feed stock, liquid feedstock, or solid feedstock, as applicable. (1) Gaseous feedstock. You must calculate, from each ammonia manufacturing unit, the CO 2 process emissions from gaseous feedstock according to Equation G

- 1 of this section:

Where: CO 2,G,k = Annual CO 2 emissions arising from gaseous feedstock consumption (metric tons). Fdstk

n = Volume of the gaseous feedstock used in month n (scf of feedstock). CC n = Carbon content of the gaseous feedstock, for month n (kg C per kg of feedstock), determined according to 98.74(c). MW = Molecular weight of the gaseous feedstock (kg/kg

- mole). MVC = Molar volume conversion factor (849.5 scf per kg

- mole at standard conditions).Page 3 of 10

44/12 = Ratio of molecular weights, CO 2 to carbon. 0.001 = Conversion factor from kg t o metric tons. k = Processing unit. n = Number of month. (2) Liquid feedstock. You must calculate, from each ammonia manufacturing unit, the CO 2 process emissions from liquid feedstock according to Equation G

- 2 of this section:

Where: CO 2,L ,k = Annual CO 2 emissions arising from liquid feedstock consumption (metric tons). Fdstk n = Volume of the liquid feedstock used in month n (gallons of feedstock). CC n = Carbon content of the liquid feedstock, for month n (kg C per gallon of feedstock) determined accordi ng to 98.74(c). 44/12 = Ratio of molecular weights, CO 2 to carbon. 0.001 = Conversion factor from kg to metric tons. k = Processing unit. n = Number of month. (3) Solid feedstock. You must calculate, from each ammonia manufacturing unit, the CO 2 process emissions from solid feedstock according to Equation G

- 3 of this section:

Where: CO 2,S,k = Annual CO 2 emissions arising from solid feedstock consumption (metric tons). Fdstk n = Mass of the solid feedstock used in month n (kg of feedstock).Page 4 of 10

CC n = Carbon content of the solid feedstock, for month n (kg C per kg of feedstock), determined according to 98.74(c). 44/12 = Ratio of molecular weights, CO 2 to carbon. 0.001 = Conversion factor from kg to metric tons. k = Processing unit. n = Number of month. (4) You must calculate the annual process CO 2 emissions from each ammonia processing unit k at your facility

according to Equation G

- 4 of this section:

Where: E CO2k = Annual CO 2 emissions from each ammonia processing unit k (metric tons). k = Processing unit. (5) You must determine the combined CO 2 emissions from all ammonia processing units at your facility

using Equation G

- 5 of this section.

Where: CO 2 = Annual combined CO 2 emissions from all ammonia processing units (metric tons) (CO 2 process emissi ons reported under this subpart may include CO 2 that is later consumed on site for urea production, and therefore is not released to the ambient air from the ammonia manufacturing process unit(s)). E CO2k = Annual CO 2 emissions from each ammonia processing unit (metric tons). k = Processing unit. n = Total number of ammonia processing units.Page 5 of 10

(c) If GHG emissions from an ammonia manufacturing unit are vented through the same stack as an y combustion unit or process equipment that reports CO 2 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 u sed 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 .74**  **Monitoring and QA/QC requirements.** (a) You must continuously measure the quantity of gaseous or liquid feedstock consumed using a flow meter. The quantity of solid feedstock consumed can be obtained from company records and aggregated on a monthly basi s. (b) You must document the procedures used to ensure the accuracy of the estimates of feedstock consumption. (c) You must determine monthly carbon contents and the average molecular weight of each feedstock consumed from reports from your supplier. As an alternative to using supplier information on carbon contents, you can also collect a sample of each feedstock on a monthly basis and anal yz e the carbon content and molecular weight of the fuel using any of the following methods listed in paragraphs (c)(1) through (c)(8) of this section, as applicable. (1) ASTM D1945

- 03 Standard Test Method for Analy sis of Natural Gas by Gas Chromatograph y (incorporated b y reference, see §98.7). (2) ASTM D1946

- 90 (Reapproved 2006) Standard Practice for Anal ys is of Reformed Gas b y Gas Chromatography (incorporated b y reference, see §98.7).Page 6 of 10

(3) ASTM D2502

- 04 (Reapproved 2002) Standard Test Method for Estimation of Mean Relative Molecular Mass of Petroleum Oils from Viscosity Measurements (incorporated by reference, see §98.7). (4) ASTM D2503

- 92 (Reapproved 2007) Standard Test Method for Relative Molecular Mass (Molecular Weight) of Hydrocarbons b y Thermoelectric Measurement of Vapor Pressure (incorporated b y reference, see §98.7). (5) ASTM D3238

- 95 (Reapproved 2005) Standard Tes t Method for Calculation of Carbon Distribution and Structural Group Analy sis of Petroleum Oils by the n

- d

- M Method (incorporated b y reference, see §98.7). (6) ASTM D5291

- 02 (Reapproved 2007) Standard Test Methods for Instrumental Determination of Carbon, Hydrogen, and Nitrogen in Petroleum Products and Lubricants (incorporated b y reference, see §98.7). (7) ASTM D3176

- 89 (Reapproved 2002) Standard Practice for Ultimate Analy sis of Coal and Coke (incorporated by reference, see §98.7). (8) ASTM D5373

- 08 Stand ard Methods for Instrumental Determination of Carbon, Hydrogen, and Nitrogen in L aboratory Samples of Coal (incorporated by reference, see §98.7). (d) Calibrate all oil and gas flow meters that are used to measure liquid and gaseous feedstock volumes and f

low rates (except for gas billing meters) according to the monitoring and QA/QC requirements for the Tier 3 methodology in §98.34(b)(1). Perform oil tank drop measurements (if used to quantify feedstock volumes) according to §98.34(b)(2). (e) For quality a ssurance and quality control of the supplier data, on an annual basis, you must measure the carbon contents of a representative sample of the feedstocks consumed using the appropriate ASTM Method as listed in paragraphs (c)(1) through (c)(8) of this sectio n.Page 7 of 10

(f) You may

use company

records or an engineering estimate to determine the annual ammonia production and the annu al methanol production

. (g) If CO 2 from ammonia production is used to produce urea at the same facility, you must determine the q

uantity of urea produced using methods or plant instruments used for accounting purposes (such as sales records). You must document the procedures used to ensure the accuracy

of the estimates of urea produced. **§98.75 Procedures for estimating missing data.**  A complete record of all measured parameters used in the GHG emissions calculations is required. Therefore, whenever the monitoring and quality assurance procedures in §98.74 cannot be followed (e.g., if a meter malfunctions during unit operation), a substitute data value for the missing parameter shall be used in the calculations following paragraphs (a) and (b) of this section. You must document and keep records of the procedures used for all such estimates. (a) For missing data on monthly carbon contents of feedstock, the substitute data value shall be the arithmetic average of the quality- assured values of that carbon content in the month preceding and the month immediately following the missing data incident. If no quality

- assured data are availabl e prior to the missing data incident, the substitute data value shall be the first quality

- assured value for carbon content obtained in the month after the missing data period. (b) For missing feedstock supply rates used to determine monthly feedstock cons umption, yo u must determine the best available estimate(s) of the parameter(s), based on all available process data. **§ 98. 76**  **Data reporting requirements.**Page 8 of 10

In addition to the information required b y § 98. 3(c), each annual report must contain the information specified in paragraphs (a) and (b) of this section, as applicable for each ammonia manufacturing process unit. (a) If a CEMS is used to measure CO 2 emissions, then you must report the relevant information required under § 98. 36 for the Tier 4 Calculation Methodology and the information in paragraphs (a)(1) through ( 3 ) of this section: (1) Annual quantity of each type of feedstock consumed for ammonia manufacturing (scf of feedstock or gallons of feedstock or kg of feedstock). (2) Method used for deter mining quantity

of feedstock used. (3) Annual ammonia production (metric tons, sum of all process units reported within subpart G). (b) If a CEMS is not used to measure emissions, then you must report all of the following information in this paragraph (b): (1) Annual CO 2 process emissions (metric tons) for each ammonia manufacturing process unit. (2) Annual quantity of each type of feedstock consumed for ammonia manufacturing (scf of feedstock or gallons of feedstock or kg of feedstock)

. (3) Method used for determining quantity of monthly

feedstock used. (4) Whether carbon content for each feedstock for month n is based on reports from the supplier or anal ys is of carbon content. (5) If carbon content of feedstock for month n is based on anal ys is, the test method used. (6) Sampling anal ys is results of carbon content of feedstock as determined for QA/QC of supplier data under § 98. 74(e).Page 9 of 10

(7) Annual average carbon content of each type of feedstock consumed

. (8) Reserved

. (9) Reserved

. (10) Reserv ed

. (11) Reserved

. (12) Annual urea production (metric tons) and method used to determine urea production. (13) Annual CO 2 emissions (metric tons) from the steam reforming of a hydrocarbon or the gasification of solid and liquid raw material at the ammonia manufacturing process unit used to produce urea and the method used to determine the CO 2 consumed in urea production. (14) Annual ammonia production (metric tons, sum of all process units reported within subpart G). (15) Annual methanol production for each process unit (metric tons) , regardless of whether the methanol is subsequently destroyed, vented, or sold as product

. **§ 98. 77**  **Records that must be retained.** In addition to the records required b y § 98. 3(g), you must retain the following records specified in paragraphs (a) through ( c ) of this section for each ammonia manufacturing unit. (a) If a CEMS is used to measure emissions, retain records of all feedstock purchases in addition to the requirements i n § 98. 37 for the Tier 4 Calculation Methodology

. (b) If a CEMS is not used to measure process CO 2 emissions, you must also retain the records specified in paragraphs (b)(1) through (b)(2) of this section: (1) Records of all anal ys es and calculations condu cted for reported data as listed in § 98. 76(b).Page 10 of 10

(2) Monthly

records of carbon content of feedstock from supplier and/or all anal ys es conducted of carbon content. (c) Verification software records . You must keep a record of the file generated by the verific ation software specified in § 98 .5(b) for the applicable data specified in paragraphs (c)(1) through ( 7) of this section. Retention of this file satisfies the recordkeeping requirement for the data in paragraphs (c)(1) through ( 7) of this section. (1) Volume of each gaseous feedstock used in month (scf of feedstock) (in Equation G

- 1 of § 98.73 ). (2) Carbon content of each gaseous feedstock, for month (kg C per kg of feedstock) (in Equation G

- 1). (3) Molecular weight of each gaseous feedstock per ammonia man ufacturing unit with gaseous feedstock (kg/kg

- mole) (Equation G

- 1). (4) Volume of each liquid feedstock used in month (gallons of feedstock) (Equation G

- 2 of § 98.73 ). (5) Carbon content of each liquid feedstock, for month (kg C per gallon of feedstock) (E quation G

- 2). (6) Mass of each solid feedstock used in month (kg of feedstock) (Equation G

- 3 of § 98.73 ). (7) Carbon content of each solid feedstock, for month (kg C per kg of feedstock) (Equation G

- 3). **§98.78 Definitions.** All terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of this part.