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Subpart S—Lime Manufacturing

§98.190 Definition of the source category.

(a) Lime manufacturing plants (LMPs) engage in the manufacture of a lime product by

calcination of limestone, dolomite, shells or other calcareous substances as defined in 40 CFR 

63.7081(a)(1).

(b) This source category includes all LMPs unless the LMP is located at a kraft pulp mill, 

soda pulp mill, sulfite pulp mill, or only processes sludge containing calcium carbonate from 

water softening processes. The lime manufacturing source category consists of marketed and 

non-marketed lime manufacturing facilities.

(c) Lime kilns at pulp and paper manufacturing facilities must report emissions under 

subpart AA of this part (Pulp and Paper Manufacturing).

§98.191 Reporting threshold.

You must report GHG emissions under this subpart if your facility is a lime 

manufacturing plant as defined in §98.190 and the facility meets the requirements of either 

§98.2(a)(1) or (a)(2).

§98.192 GHGs to report.

You must report:

(a) CO2 process emissions from lime kilns.

(b) CO2 emissions from fuel combustion at lime kilns.

(c) N2O and CH4 emissions from fuel combustion at each lime kiln. You must report 

these emissions under 40 CFR part 98, subpart C (General Stationary Fuel Combustion Sources).
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(d) CO2, N2O, and CH4 emissions from each stationary fuel combustion unit other than 

lime kilns. You must report these emissions under 40 CFR part 98, subpart C (General Stationary

Fuel Combustion Sources).

(e) CO2 collected and transferred off site under 40 CFR part 98, following the 

requirements of subpart PP of this part (Suppliers of Carbon Dioxide (CO2)).

§98.193 Calculating GHG emissions.

You must calculate and report the annual process CO2 emissions from all lime kilns 

combined using the procedure in paragraphs (a) and (b) of this section.

(a) If all lime kilns meet the conditions specified in §98.33(b)(4)(ii) or (iii), you must 

calculate and report under this subpart the combined process and combustion CO2 emissions 

from all lime kilns by operating and maintaining a CEMS to measure CO2 emissions according 

to the Tier 4 Calculation Methodology specified in §98.33(a)(4) and all associated requirements 

for Tier 4 in subpart C of this part (General Stationary Fuel Combustion Sources).

(b) If CEMS are not required to be used to determine CO2 emissions from all lime kilns 

under paragraph (a) of this section, then you must calculate and report the process and 

combustion CO2 emissions from the lime kilns by using the procedures in either paragraph (b)(1) 

or (b)(2) of this section.

(1) Calculate and report under this subpart the combined process and combustion CO2

emissions from all lime kilns by operating and maintaining a CEMS to measure CO2 emissions 

from all lime kilns according to the Tier 4 Calculation Methodology specified in §98.33(a)(4) 

and all associated requirements for Tier 4 in subpart C of this part (General Stationary Fuel 

Combustion Sources).
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(2) Calculate and report process and combustion CO2 emissions from all lime kilns 

separately using the procedures specified in paragraphs (b)(2)(i) through (v) of this section.

(i) You must calculate a monthly emission factor for each type of lime produced using 

Equation S-1 of this section. Calcium oxide and magnesium oxide content must be analyzed 

monthly for each lime product type that is produced:

Where:

EFLIME,i,n = Emission factor for lime type i, for month n (metric tons CO2/ton lime).

SRCaO = Stoichiometric ratio of CO2 and CaO for calcium carbonate [see Table S-1 of 

this subpart] (metric tons CO2/metric tons CaO).

SRMgO = Stoichiometric ratio of CO2 and MgO for magnesium carbonate (See Table S-1 

of this subpart) (metric tons CO2/metric tons MgO).

CaOi,n = Calcium oxide content for lime type i, for month n, determined according to 

§98.194(c) (metric tons CaO/metric ton lime).

MgOi,n = Magnesium oxide content for lime type i, for month n, determined according to 

§98.194(c) (metric tons MgO/metric ton lime).

2000/2205 = Conversion factor for tons to metric tons.

(ii) You must calculate a monthly emission factor for each type of calcined byproduct or 

waste sold (including lime kiln dust) using Equation S-2 of this section:

Where:
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EFLKD,i,n = Emission factor for calcined lime byproduct/waste type i sold, for month n 

(metric tons CO2/ton lime byproduct).

SRCaO = Stoichiometric ratio of CO2 and CaO for calcium carbonate (see Table S-1 of 

this subpart((metric tons CO2/metric tons CaO).

SRMgO = Stoichiometric ratio of CO2 and MgO for magnesium carbonate (See Table S-1 

of this subpart) (metric tons CO2/metric tons MgO).

CaOLKD,i,n = Calcium oxide content for calcined lime byproduct/waste type i sold, for 

month n (metric tons CaO/metric ton lime).

MgOLKD,i,n = Magnesium oxide content for calcined lime byproduct/waste type i sold, for 

month n (metric tons MgO/metric ton lime).

2000/2205 = Conversion factor for tons to metric tons.

(iii) You must calculate the annual CO2 emissions from each type of calcined byproduct 

or waste that is not sold (including lime kiln dust and scrubber sludge) using Equation S-3 of this 

section:

Where:

Ewaste,i = Annual CO2 emissions for calcined lime byproduct or waste type i that is not 

sold (metric tons CO2).

SRCaO = Stoichiometric ratio of CO2 and CaO for calcium carbonate (see Table S-1 of 

this subpart) (metric tons CO2/metric tons CaO).

SRMgO = Stoichiometric ratio of CO2 and MgO for magnesium carbonate (See Table S-1 

of this subpart) (metric tons CO2/metric tons MgO).
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CaOwaste,i = Calcium oxide content for calcined lime byproduct or waste type i that is not 

sold (metric tons CaO/metric ton lime).

MgOwaste,i = Magnesium oxide content for calcined lime byproduct or waste type i that is 

not sold (metric tons MgO/metric ton lime).

Mwaste,i = Annual weight or mass of calcined byproducts or wastes for lime type i that is 

not sold (tons).

2000/2205 = Conversion factor for tons to metric tons.

(iv) You must calculate annual CO2 process emissions for all lime kilns using Equation 

S-4 of this section:

Where:

ECO2 = Annual CO2 process emissions from lime production from all lime kilns (metric 

tons/year).

EFLIME,i,n = Emission factor for lime type i produced, in calendar month n (metric tons 

CO2/ton lime) from Equation S-1 of this section.

MLIME,i,n = Weight or mass of lime type i produced in calendar month n (tons).

EFLKD,i,n = Emission factor of calcined byproducts or wastes sold for lime type i in 

calendar month n, (metric tons CO2/ton byproduct or waste) from Equation S-2 of this section.

MLKD,i,n = Monthly weight or mass of calcined byproducts or waste sold (such as lime 

kiln dust, LKD) for lime type i in calendar month n (tons).

Ewaste,i = Annual CO2 emissions for calcined lime byproduct or waste type i that is not 

sold (metric tons CO2) from Equation S-3 of this section.

t = Number of lime types produced
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b = Number of calcined byproducts or wastes that are sold.

z = Number of calcined byproducts or wastes that are not sold.

(v) Calculate and report under subpart C of this part (General Stationary Fuel 

Combustion Sources) the combustion CO2 emissions from each lime kiln according to the 

applicable requirements in subpart C.

§98.194 Monitoring and QA/QC requirements.

(a) You must determine the total quantity of each type of lime product that is produced 

and each calcined byproduct or waste (such as lime kiln dust) that is sold. The quantities of each 

should be directly measured monthly with the same plant instruments used for accounting 

purposes, including but not limited to, calibrated weigh feeders, rail or truck scales, and barge 

measurements. The direct measurements of each lime product shall be reconciled annually with 

the difference in the beginning of and end of year inventories for these products, when 

measurements represent lime sold.

(b) You must determine the annual quantity of each calcined byproduct or waste 

generated that is not sold by either direct measurement using the same instruments identified in 

paragraph (a) of this section or by using a calcined byproduct or waste generation rate.

(c) You must determine the chemical composition (percent total CaO and percent total 

MgO) of each type of lime product that is produced and each type of calcined byproduct or waste 

sold according to paragraph (c)(1) or (2) of this section. You must determine the chemical 

composition of each type of lime product that is produced and each type of calcined byproduct or 

waste sold on a monthly basis. You must determine the chemical composition for each type of 

calcined byproduct or waste that is not sold on an annual basis.
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(1) ASTM C25-06 Standard Test Methods for Chemical Analysis of Limestone, 

Quicklime, and Hydrated Lime (incorporated by reference—see §98.7).

(2) The National Lime Association's CO2 Emissions Calculation Protocol for the Lime 

Industry English Units Version, February 5, 2008 Revision-National Lime Association 

(incorporated by reference—see §98.7).

(d) You must use the analysis of calcium oxide and magnesium oxide content of each 

lime product that is produced and that is collected during the same month as the production data 

in monthly calculations.

(e) You must follow the quality assurance/quality control procedures (including 

documentation) in National Lime Association's CO2 Emissions Calculation Protocol for the Lime 

Industry English Units Version, February 5, 2008 Revision—National Lime Association 

(incorporated by reference—see §98.7).

§98.195 Procedures for estimating missing data.

For the procedure in §98.193(b)(1), a complete record of all measured parameters used in 

the GHG emissions calculations is required (e.g., oxide content, quantity of lime products, 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 in paragraphs 

(a) or (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 quantity of lime produced (by lime type), and quantity

of calcined byproduct or waste produced and sold, the substitute data value shall be the best 

available estimate based on all available process data or data used for accounting purposes.
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(b) For missing values related to the CaO and MgO content, you must conduct a new 

composition test according to the standard methods in §98.194 (c)(1) or (c)(2).

§ 98.196 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.

(a) If a CEMS is used to measure CO2 emissions, then you must report under this subpart 

the relevant information required by § 98.36 and the information listed in paragraphs (a)(1) 

through (8) of this section.

(1) Method used to determine the quantity of lime that is produced and quantity of lime 

that is sold.

(2) Method used to determine the quantity of calcined lime byproduct or waste sold.

(3) Beginning and end of year inventories for each lime product that is produced, by type.

(4) Beginning and end of year inventories for calcined lime byproducts or wastes sold, by

type.

(5) Annual amount of calcined lime byproduct or waste sold, by type (tons).

(6) Annual amount of lime product sold, by type (tons).

(7) Annual amount of calcined lime byproduct or waste that is not sold, by type (tons).

(8) Annual amount of lime product not sold, by type (tons).

(b) If a CEMS is not used to measure CO2 emissions, then you must report the 

information listed in paragraphs (b)(1) through (21) of this section.

(1) Annual CO2 process emissions from all lime kilns combined (metric tons).

(2) Reserved.

(3) Reserved.
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(4) Standard method used (ASTM or NLA testing method) to determine chemical 

compositions of each lime type produced and each calcined lime byproduct or waste type.

(5) Reserved.

(6) Reserved.

(7) Method used to determine the quantity of lime produced and/or lime sold.

(8) Reserved.

(9) Method used to determine the quantity of calcined lime byproduct or waste sold.

(10) Reserved.

(11) Reserved.

(12) Reserved.

(13) Beginning and end of year inventories for each lime product that is produced.

(14) Beginning and end of year inventories for calcined lime byproducts or wastes sold.

(15) Annual lime production capacity (tons) per facility.

(16) Number of times in the reporting year that missing data procedures were followed to 

measure lime production (months) or the chemical composition of lime products sold (months).

(17) Indicate whether CO2 was used on-site (i.e. for use in a purification process). If CO2

was used on-site, provide the information in paragraphs (b)(17)(i) and (ii) of this section.

(i) The annual amount of CO2 captured for use in the on-site process.

(ii) The method used to determine the amount of CO2 captured.

(18) Annual quantity (tons) of lime product sold, by type.

(19) Annual emission factors for each lime product type produced.

(20) Annual emission factors for each calcined byproduct/waste by lime type that is sold.
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(21) Annual average results of chemical composition analysis of each type of lime 

product produced and calcined byproduct/waste sold. 

§ 98.197 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 (c) of this section.

(a) Annual operating hours in calendar year.

(b) Records of all analyses (e.g. chemical composition of lime products, by type) and 

calculations conducted.

(c) Verification software records. You must keep a record of the file generated by the 

verification software specified in § 98.5(b) for the applicable data specified in paragraphs (c)(1) 

through (9) of this section. Retention of this file satisfies the recordkeeping requirement for the 

data in paragraphs (c)(1) through (9) of this section.

(1) Monthly calcium oxide content for each lime type, determined according to § 

98.194(c) (metric tons CaO/ metric ton lime) (Equation S-1 of § 98.193).

(2) Monthly magnesium oxide content for each lime type, determined according to § 

98.194(c) (metric tons MgO/ metric ton lime) (Equation S-1).

(3) Monthly calcium oxide content for each calcined lime byproduct or waste type sold 

(metric tons CaO/ metric ton lime) (Equation S-2 of § 98.193).

(4) Monthly magnesium oxide content for each calcined lime byproduct or waste type 

sold (metric tons MgO/ metric ton lime) (Equation S-2).

(5) Calcium oxide content for each calcined lime byproduct or waste type that is not sold 

(metric tons CaO/ metric ton lime) (Equation S-3 of § 98.193).
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(6) Magnesium oxide content for each calcined lime byproduct or waste type that is not 

sold (metric tons MgO/ metric ton lime) (Equation S-3).

(7) Annual weight or mass of calcined byproducts or wastes for lime type that is not sold 

(tons) (Equation S-3).

(8) Monthly weight or mass of each lime type produced (tons) (Equation S-4 of § 

98.193).

(9) Monthly weight or mass of each calcined byproducts or wastes sold (tons) (Equation 

S-4).

§98.198 Definitions.

All terms used in this subpart have the same meaning given in the Clean Air Act and 

subpart A of this part.

Table S-1 to Subpart S of Part 98—Basic Parameters for the Calculation of Emission 

Factors for Lime Production

Variable Stoichiometric ratio

SRCaO 0.7848

SRMgO 1.0918