---
kind: "section"
citation: "40 C.F.R. § 98.83"
title: "40"
number: "98.83"
heading: "Calculating GHG emissions."
url: "https://uscodex.org/cfr/40/98.83"
---

# §98.83. Calculating GHG emissions.


You must calculate and report the annual process CO2 emissions from each kiln using the procedure in paragraphs [(a)](#a) and [(b)](#b) of this section.

- (a) For each cement kiln that meets the conditions specified in § [98.33(b)(4)(ii)](/cfr/40/98.33.md?p=b-4-ii) or [(b)(4)(iii)](/cfr/40/98.33.md?p=b-4-iii), you must calculate and report under this subpart the combined process and combustion CO2 emissions by operating and maintaining a CEMS to measure CO2 emissions according to the Tier 4 Calculation Methodology specified in [§ 98.33(a)(4)](/cfr/40/98.33.md?p=a-4) and all associated requirements for Tier 4 in [subpart C](/cfr/40/subpartC.md) of this part (General Stationary Fuel Combustion Sources).
- (b) For each kiln that is not subject to the requirements in [paragraph (a)](#a) of this section, calculate and report the process and combustion CO2 emissions from the kiln by using the procedure in either paragraph [(c)](#c) or [(d)](#d) of this section.
- (c) Calculate and report under this subpart the combined process and combustion CO2 emissions by operating and maintaining a CEMS to measure CO2 emissions according to the Tier 4 Calculation Methodology specified in [§ 98.33(a)(4)](/cfr/40/98.33.md?p=a-4) and all associated requirements for Tier 4 in [subpart C](/cfr/40/subpartC.md) of this part (General Stationary Fuel Combustion Sources).
- (d) Calculate and report process and combustion CO2 emissions separately using the procedures specified in [paragraphs (d)(1) through (d)(4)](#d-1..d-4) of this section.
  - (1) Calculate CO2 process emissions from all kilns at the facility using equation H-1 to this section:
  - (2) **CO—** 2 emissions from clinker production. Calculate CO2 emissions from each kiln using Equations H-2 through H-5 of this section.
    - (i) **Kiln-Specific Clinker Emission Factor.**
      - (A) **Calculate the kiln-specific clinker emission factor using Equation H-3 of this section.**
      - (B) Non-calcined CaO is CaO that remains in the clinker in the form of CaCO3 and CaO in the clinker that entered the kiln as a non-carbonate species. Non-calcined MgO is MgO that remains in the clinker in the form of MgCO3 and MgO in the clinker that entered the kiln as a non-carbonate species.
    - (ii) **Kiln-Specific CKD Emission Factor.**
      - (A) Calculate the kiln-specific CKD emission factor for CKD not recycled to the kiln using Equation H-4 of this section.
      - (B) Non-calcined CaO is CaO that remains in the CKD in the form of CaCO3 and CaO in the CKD that entered the kiln as a non-carbonate species. Non-calcined MgO is MgO that remains in the CKD in the form of MgCO3 and MgO in the CKD that entered the kiln as a non-carbonate species.
  - (3) **CO—** 2emissions from raw materials from each kiln. Calculate CO2 emissions from raw materials using equation H-5 to this section:
  - (4) Calculate and report under [subpart C](/cfr/40/subpartC.md) of this part (General Stationary Fuel Combustion Sources) the combustion CO2 emissions from the kiln according to the applicable requirements in subpart C.

## Notes

### Amendments

[74 FR 56374, Oct. 30, 2009, as amended at 75 FR 66461, Oct. 28, 2010; 89 FR 31905, Apr. 25, 2024]

### Authority

Authority: 42 U.S.C. 7401-7671q.

### Source

Source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.

### Amendments

[74 FR 56374, Oct. 30, 2009, as amended at 75 FR 66461, Oct. 28, 2010; 89 FR 31905, Apr. 25, 2024]