Page 1 of 14

**Subpart AA**

**— Pulp and Paper Manufacturing**  § 98.270 Definition of source category. (a) The pulp and paper manufacturing source category consists of facilities that produce market pulp ( i.e. , stand
alone pulp facilities), manufacture pulp and paper ( i.e. , integrated facilities), produce paper products from purchased pulp, produce secondary fiber from recycled paper, convert paper into paperboard products ( e.g. , containers), or operate coa ting and laminating processes. (b) The emission units for which GHG emissions must be reported are listed in paragraphs (b)(1) through (b)(5) of this section: (1) Chemical recovery furnaces at kraft and soda mills (including recovery furnaces that burn spe nt pulping liquor produced by both the kraft and semichemical process). (2) Chemical recovery combustion units at sulfite facilities. (3) Chemical recovery combustion units at stand
- alone semichemical facilities. (4) Pulp mill lime kilns at kraft and soda facilities. (5) Systems for adding makeup chemicals (CaCO 3 , Na 2 CO 3 ) in the chemical recovery areas of chemical pulp mills. § 98.271 Reporting threshold.Page 2 of 14

You must report GHG emissions under this subpart if your facility contains a pulp and paper manufacturi ng process and the facility meets the requirements of either §98.2(a)(1) or (a)(2). § 98.272 GHGs to report. You must report the emissions listed in paragraphs (a) through (f) of this section: (a) CO 2 , biogenic CO 2 , CH 4 , and N 2 O emissions from each kraft
o r soda chemical recovery furnace. (b) CO 2 , biogenic CO 2 , CH 4 , and N 2 O emissions from each sulfite chemical recovery combustion unit. (c) CO 2 , biogenic CO 2 , CH 4 , and N 2 O emissions from each stand
- alone semichemical chemical recovery combustion unit. (d) CO 2 , biogenic CO 2 , CH 4 , and N 2 O emissions from each kraft or soda pulp mill lime kiln. (e) CO 2 emission s from addition of makeup chemicals (CaCO 3 , Na 2 CO 3 ) in the chemical recovery areas of chemical pulp mills. (f) CO 2 , CH 4 , andN 2O combustion emissions from each stationary combustion unit. You must calculate and report these emissions under subpart C of this part (General Stationary Fuel Combustion Sources) by following the requirements of subpart C. § 98.273 Calculating GHG emissions. (a) For each chemical recovery furnace located at a kraft or soda facility, you must determine CO 2 , biogenic CO 2 , CH 4 , and N 2 O emissions using the procedures in paragraphs (a)(1) throughPage 3 of 14

(a)(3) of this section. CH 4 and N 2O emissions must be calc ulated as the sum of emissions from combustion of fossil fuels and combustion of biomass in spent liquor solids. (1) Calculate fossil fuel
-based CO 2 emission s from direct measurement of fossil fuels consumed and default emissions factors according to the T ier 1 methodology for stationary combustion sources in §98.33(a)(1). A higher tier from §98.33(a) may be used to calculate fossil fuel
-based CO 2 emission s if the respective monitoring and QA/QC requirements described in §98.34 are met. (2) Calculate fossil fuel
-based CH 4 and N 2O emissions from direct measurement of fossil fuels consumed, default or site
specific HHV, and default emissions factors and convert to metric tons of CO 2 equivalent according to the methodology for stationary combustion sources in § 98.33(c). (3) Calculate biogenic CO 2 emission s and emissions of CH 4 and N 2O from biomass using measured quantities of spent liquor solids fired, site
- specific HHV, and default emissions factors, according to Equation AA

– 1 of this section:

Where: CO 2 , CH 4 , or N 2O, from Biomass = Biogenic CO 2 emission s or emissions of CH 4 or N 2O from spent liquor solids combustion (metric tons per year).Page 4 of 14

Solids = Mass of spent liquor solids combusted (short tons per year) determined according to §98.274(b). HHV = Annual high heat value of the spent liquor solids (mmBtu per kilogram) determined according to §98.274(b). (EF) = Default emission factor for CO 2 , CH 4 , or N 2 O, from Table AA

– 1 of this subpart (kg CO 2 , CH 4 , or N 2 O per mmBtu). 0.90718 = Conversion factor from short tons to metric tons. (b) For each chemical recovery combustion unit located at a sulfite or stand
- alone semichemical facility, you must determine CO 2 , CH 4 , and N 2 O emissions using the procedures in paragraphs (b)(1) through (b)(4) of this section: (1) Calculate fossil CO 2 emission s from fossil fuels from direct measurement of fossil fuels consumed and default emissions factors according to the Tier 1 Calculation Methodology for stationary combustion sources in §98.33(a)(1). A higher tier from §98.33(a) may be used to calculate fossil fuel
based CO 2 emission s if the respective monitoring and QA/QC requirements described in §98.34 are met. (2) Calculate CH 4 and N 2 O emissions from fossil fuels from direct measurement of fossil fuels consumed, default or site
specific HHV, and default emissions factors and convert to metric tons of CO 2 equivalent according to the methodology for stationary combustion sources in §98.33(c).Page 5 of 14

(3) Calculate biogenic CO 2 emission s using measured quantiti es of spent liquor solids fired and the carbon content of the spent liquor solids, according to Equation AA

– 2 of this section:

Where: Biogenic CO 2 = Annual CO 2 mass emissions for spent liquor solids combustion (metric tons per year). Solids = Mass of the spent liquor solids combusted (short tons per year) determined according to §98.274(b). CC = Annual carbon content of the spent liquor solids, determined according to §98.274(b) (percent by weight, expressed as a decimal fraction, e.g. , 95% = 0.95). 44 /12 = Ratio of molecular weights, CO 2 to carbon. 0.90718 = Conversion from short tons to metric tons. (4) Calculate CH 4 and N 2O emissions from biomass using Equation AA

– 1 of this section and the default CH 4 and N 2O emissions factors for kraft facilities in Table AA

– 1 of this subpart and convert the CH 4 or N 2O emissions to metric tons of CO 2 equivalent by multiplying each annual CH 4 and N 2O emissions total by the appropriate global warming potential (GWP) factor from Table A

– 1 of subpart A of this part. (c) For each pulp mill lime kiln located at a kraft or soda facility, you must determine CO 2 , CH 4 , and N 2O emissions usingPage 6 of 14

the procedures in paragraphs (c)(1) through (c)(3) of this section: (1) Calculate CO 2 emission s from fossil fuel from direct measurement of fossil fuels consumed and default HHV and default emissions factors, according to the Tier 1 Calculation Methodology for stationary combustion sources in §98.33(a)(1). A higher tier from §98.33(a) may be used t o calculate fossil fuel
based CO 2 emission s if the respective monitoring and QA/QC requirements described in §98.34 are met. (2) Calculate CH 4 and N 2 O emissions from fossil fuel from direct measurement of fossil fuels consumed, default or site
specific HHV, and default emissions factors and convert to metric tons of CO 2 equivalent according to the methodology for stationary combustion sources in §98.33 (c); use the default HHV listed in Table C

– 1 of subpart C and the default CH 4 and N 2 O emissions factors listed in Table AA

– 2 of this subpart. (3) Biogenic CO 2 emission s from conversion of CaCO 3 to CaO are included in the biogenic CO 2 estimates calculated fo r the chemical recovery furnace in paragraph (a)(3) of this section. (d) For makeup chemical use, you must calculate CO 2 emission s by using direct or indirect measurement of the quantity of chemicals added and ratios of the molecular weights of CO 2 and the makeup chemicals, according to Equation AA

– 3 of this section:Page 7 of 14

Where:
CO 2 = CO 2 mass emissions from makeup chemicals (kilograms/yr). M (CaCO 3 ) = Make
- up quantity of CaCO 3used for the reporting year (metric tons per year). M (NaCO 3 ) = Make
- up quantity of Na 2 CO 3used for the reporting year (metric tons per year). 44 = Molecular weight of CO 2 . 100 = Molecular weight of CaCO 3 . 105.99 = Molecular weight of Na 2 CO 3 . § 98.274 Monitoring and QA/QC requirements. (a) Each facility subject to this subpart must qualit y assure the GHG emissions data according to the applicable requirements in §98.34. All QA/QC data must be available for inspection upon request. (b) Fuel properties needed to perform the calculations in Equations AA

– 1 and AA

– 2 of this subpart must be dete rmined according to paragraphs (b)(1) through (b)(3) of this section. (1) High heat values of black liquor must be determined no less than annually using T684 om

– 06 Gross Heating Value of Black Liquor, TAPPI (incorporated by reference, see §98.7). If
measu rements are performed more frequently than annually, then the high heat value used in Equation AA

– 1 of this subpart must be based on the average of the representative measurements made during the year.Page 8 of 14

(2) The annual mass of spent liquor solids must be det ermined using either of the methods specified in paragraph (b)(2)(i) or (b)(2)(ii) of this section. (i) Measure the mass of spent liquor solids annually (or more frequently) using T

– 650 om

– 05 Solids Content of Black Liquor, TAPPI (incorporated by reference in §98.7). If measurements are performed more frequently than annually, then the mass of spent liquor solids used in Equation AA

– 1 of this subpart must be based on the average of the representative measurements made during the year. (ii) Determine the annual mass of spent liquor solids based on records of measurements made with an online measurement system that determines the mass of spent liquor solids fired in a chemical recovery furnace or chemical recovery combustion unit. (3) Carbon analyses for spent pulping liquor must be determined no less than annually using 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). If measurements using ASTM D5373

– 08 are performed more frequently than annually, then the spent pulping liquor carbon content used in Equation AA

– 2 of this subpart must be based on the average of the representative measurements made during the year.Page 9 of 14

(c) Each facility must keep records that include a detailed explanation of how company records of measurements are used to estimate GHG emissions. The owner or operator must also document the procedures used to ensure the accuracy of the measurements of fuel, spent liquor solids, and makeup chemical usage, including, but not limited to calibration of weighing equipment, fuel flow meters, and other measurement devices. The estimated accuracy of measurements made with these devices must be recorded and the technical basis for these estimates must be provided. The procedures used to convert spent pulping liquor flow rates to units of mass ( i.e. , spent liquor solids firing rates) also must be documented. (d) Records must be made available upon request for verification of the calculations and measurements. § 98.275 Procedures for estimating missing data. A complete record of all measured parameters used in the GHG emissions calculations is required. Therefore, whenever a quality
- assured value of a required parameter is unavailable ( e.g. , if a meter malfunctions during unit operation or if a required sample is not taken), a substitute data value for the missing parameter shall be used in the calculations, according to the requirements of paragraphs (a) through (c) of this section:Page 10 of 14

(a) There are no missing data procedures for measurements of heat content and carbon content of spent pulping liquor. A
re - test must be performed if the data from any annual measurements are determined to be invalid. (b) For missing measurements of the mass of spent l iquor solids or spent pulping liquor flow rates, use the lesser value of either the maximum mass or fuel flow rate for the combustion unit, or the maximum mass or flow rate that the fuel meter can
measure. (c) For the use of makeup chemicals (carbonates), the substitute data value shall be the best available estimate of makeup chemical consumption, based on available data ( e.g. , past accounting records, production rates). The owner or operator shall document and keep records of the procedures used for all such estimates. § 98.276 Data reporting requirements. In addition to the information required by §98.3(c) and the applicable information required by §98.36, each annual report must contain the information in paragraphs (a) through (k) of this section as applicable: (a) Annual emissions of CO 2 , biogenic CO 2 , CH 4 , biogenic CH 4 N 2 O, and biogenic N 2 O (metric tons per year). (b) Annual quantities fossil fuels by type used in chemical recovery furnaces and chemical recovery combustion units inPage 11 of 14

short tons for so lid fuels, gallons for liquid fuels and scf for gaseous fuels. (c) Annual mass of the spent liquor solids combusted (short tons per year), and basis for determining the annual mass of the spent liquor solids combusted (whether based on T650 om
- 05 Solids Content of Black Liquor, TAPPI (incorporated by reference, see §98.7) or an online measurement system). (d) The high heat value (HHV) of the spent liquor solids used in Equation AA

– 1 of this subpart (mmBtu per kilogram). (e) The default emis sion factor for CO 2 , CH 4 , or N 2 O, used in Equation AA

– 1 of this subpart (kg CO 2 , CH 4 , or N 2 O per mmBtu). (f) The carbon content (CC) of the spent liquor solids, used in Equation AA

– 2 of this subpart (percent by weight, expressed as a decimal fraction, e.g. , 95% = 0.95). (g) Annual quantities of fossil fuels by type used in pulp mill lime kilns in short tons for solid fuels, gallons for liquid fuels and scf for gaseous fuels. (h) Make
- up quantity of CaCO 3 used for the reporting year (metric tons per year) us ed in Equation AA

– 3 of this subpart. (i) Make
- up quantity of Na 2 CO 3 used for the reporting year (metric tons per year) used in Equation AA

– 3 of this subpart. (j) Annual steam purchases (pounds of steam per year). (k) Total annual production of unbleached virgin chemical pulp produced onsite during the reporting year in air
- driedPage 12 of 14

metric tons per year. This total annual production value is the sum of all kraft, semichemical , soda, and sulfite pulp produced onsite, prior to bleaching, through all virgin pulping lines. Do not include mechanical pulp or secondary fiber repulped for paper production in the virgin pulp production total. § 98.277 Records that must be retained. I n addition to the information required by §98.3(g), you must retain the records in paragraphs (a) through (f) of this section. (a) GHG emission estimates (including separate estimates of biogenic CO 2 ) for each emissions source listed under §98.270(b). (b) Annual analyses of spent pulping liquor HHV for each chemical recovery furnace at kraft and soda facilities. (c) Annual analyses of spent pulping liquor carbon content for each chemical recovery combustion unit at a sulfite or semichemical pulp facility. ( d) Annual quantity of spent liquor solids combusted in each chemical recovery furnace and chemical recovery combustion unit, and the basis for detemining the annual quantity of the spent liquor solids combusted (whether based on T650 om

– 05 Solids Content o f Black Liquor, TAPPI (incorporated by reference, see §98.7) or an online measurement system). If an online measurement system is used, you must retain records ofPage 13 of 14

the calculations used to determine the annual quantity of spent liquor solids combusted from the continuous measurements. (e) Annual steam purchases. (f) Annual quantities of makeup chemicals used. § 98.278 Definitions. All terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of this part. **Table AA –** **1 to Subpart AA of Part 98** **— Kraft Pulping Liquor**  **Emissions Factors for Biomass -** **Based CO** **2 ,**  **CH 4**  **, and N** **2 O** 

**Wood furnish Biomass**  **- based emissions factors**  **(kg/mmBtu HHV)** CO 2 a CH 4 N 2 O North American Softwood 94.4 0.0019 0 .00042 North American Hardwood 93.7 0.0019 0.00042 Bagasse 95.5 0.0019 0.00042 Bamboo 93.7 0.0019 0.00042 Straw 95.1 0.0019 0.00042

a Includes emissions from both the recovery furnace and pulp mill lime kiln. **Table AA –** **2 to Subpart AA of Part 98 —**  **Kraft Lime Kiln and Calciner Emissions Factors for**  **CH 4**  **and N** **2 O** 

**Fuel Fossil fuel**  **- based emissions factors (kg/mmBtu HHV)** 

**Kraft lime kilns Kraft calciners**  CH 4 N 2 O CH 4 N 2 O Residual Oil (any type) 0.0027 0 0.0027 0.0003 Distillate Oil (any type) 0.0027 0 0.0027 0.0004 Natural Gas 0.0027 0 0.0027 0.0001 Biogas 0.0027 0 0.0027 0.0001Page 14 of 14

Petroleum coke 0.0027 0 NAs NAa Other Fuels See Table C - 2 0 See Table C - 2 See Table

C - 2

aEmission factors for kraft calciners are not available.