98.53—Calculating GHG emissions.
(a)
You must determine annual N2 O emissions from adipic acid production according to paragraphs (a)(1) or (2) of this section.
(1)
Use a site-specific emission factor and production data according to paragraphs (b) through (i) of this section.
(2)
Request Administrator approval for an alternative method of determining N2 O emissions according to paragraphs (a)(2)(i) and (ii) of this section.
(i)
You must submit the request within 45 days following promulgation of this subpart or within the first 30 days of each subsequent reporting year.
(ii)
If the Administrator does not approve your requested alternative method within 150 days of the end of the reporting year, you must determine the N2 O emissions for the current reporting period using the procedures specified in paragraphs (b) through (h) of this section.
(b)
You must conduct an annual performance test according to paragraphs (b)(1) through (3) of this section.
(1)
You must conduct the test on the vent stream from the nitric acid oxidation step of the process, referred to as the test point, according to the methods specified in § 98.54(b) through (f). If multiple adipic acid production units exhaust to a common abatement technology and/or emission point, you must sample each process in the ducts before the emissions are combined, sample each process when only one process is operating, or sample the combined emissions when multiple processes are operating and base the site-specific emission factor on the combined production rate of the multiple adipic acid production units.
(3)
You must measure the adipic acid production rate during the test and calculate the production rate for the test period in metric tons per hour.
(c)
Using the results of the performance test in paragraph (b) of this section, you must calculate an emission factor for each adipic acid unit according to Equation E-1 of this section:
Where:
EFN2O,z = Average facility-specific N2O emission factor for each adipic acid production unit “z” (lb N2O/ton adipic acid produced).
CN2O = N2O concentration per test run during the performance test (ppm N2O).
1.14 × 10−7 = Conversion factor (lb/dscf-ppm N2O).
Q = Volumetric flow rate of effluent gas per test run during the performance test (dscf/hr).
P = Production rate per test run during the performance test (tons adipic acid produced/hr).
n = Number of test runs.
(d)
If any N2 O abatement technology “N” is located after your test point, you must determine the destruction efficiency according to paragraphs (d)(1), (2), or (3) of this section.
(2)
Estimate the destruction efficiency through process knowledge. Examples of information that could constitute process knowledge include calculations based on material balances, process stoichiometry, or previous test results provided the results are still relevant to the current vent stream conditions. You must document how process knowledge was used to determine the destruction efficiency.
(3)
Calculate the destruction efficiency by conducting an additional performance test on the vent stream following the N2 O abatement technology.
(e)
If any N2 O abatement technology “N” is located after your test point, you must determine the annual amount of adipic acid produced while N2 O abatement technology “N” is operating according to § 98.54(f). Then you must calculate the abatement factor for N2 O abatement technology “N” according to Equation E-2 of this section.
Where:
AFN = Abatement utilization factor of N2O abatement technology “N” (fraction of annual production that abatement technology is operating).
Pz,N = Annual adipic acid production during which N2O abatement technology “N” was used on unit “z” (ton adipic acid produced).
Pz = Total annual adipic acid production from unit “z” (ton acid produced).
(g)
You must calculate N2 O emissions according to paragraph (g)(1), (2), (3), or (4) of this section for each adipic acid production unit.
(1)
If one N2 O abatement technology “N” is located after your test point, you must use the emissions factor (determined in Equation E-1 of this section), the destruction efficiency (determined in paragraph (d) of this section), the annual adipic acid production (determined in paragraph (f) of this section), and the abatement utilization factor (determined in paragraph (e) of this section), according to Equation E-3a of this section:
Where:
Ea,z = Annual N2O mass emissions from adipic acid production unit “z” according to this Equation E-3a (metric tons).
EFN2Oz = N2O emissions factor for unit “z” (lb N2O/ton adipic acid produced).
Pz = Annual adipic acid produced from unit “z” (tons).
DF = Destruction efficiency of N2O abatement technology “N” (percent of N2O removed from vent stream).
AF = Abatement utilization factor of N2O abatement technology “N” (percent of time that the abatement technology is operating).
2205 = Conversion factor (lb/metric ton).
(2)
If multiple N2 O abatement technologies are located in series after your test point, you must use the emissions factor (determined in Equation E-1 of this section), the destruction efficiency (determined in paragraph (d) of this section), the annual adipic acid production (determined in paragraph (f) of this section), and the abatement utilization factor (determined in paragraph (e) of this section), according to Equation E-3b of this section:
Where:
Eb,z = Annual N2O mass emissions from adipic acid production unit “z” according to this Equation E-3b (metric tons).
EFN2O,z = N2O emissions factor for unit “z” (lb N2O/ton adipic acid produced).
Pz = Annual adipic acid produced from unit “z” (tons).
DF1 = Destruction efficiency of N2O abatement technology 1 (percent of N2O removed from vent stream).
AF1 = Abatement utilization factor of N2O abatement technology 1 (percent of time that abatement technology 1 is operating).
DF2 = Destruction efficiency of N2O abatement technology 2 (percent of N2O removed from vent stream).
AF2 = Abatement utilization factor of N2O abatement technology 2 (percent of time that abatement technology 2 is operating).
DFN = Destruction efficiency of N2O abatement technology N (percent of N2O removed from vent stream).
AFN = Abatement utilization factor of N2O abatement technology N (percent of time that abatement technology N is operating).
2205 = Conversion factor (lb/metric ton).
N = Number of different N2O abatement technologies.
(3)
If multiple N2 O abatement technologies are located in parallel after your test point, you must use the emissions factor (determined in Equation E-1 of this section), the destruction efficiency (determined in paragraph (d) of this section), the annual adipic acid production (determined in paragraph (f) of this section), and the abatement utilization factor (determined in paragraph (e) of this section), according to Equation E-3c of this section:
Where:
Ec,z = Annual N2O mass emissions from adipic acid production unit “z” according to this Equation E-3c (metric tons).
EFN2O,z = N2O emissions factor for unit “z” (lb N2O/ton adipic acid produced).
Pz = Annual adipic acid produced from unit “z” (tons).
DFN = Destruction efficiency of N2O abatement technology “N” (percent of N2O removed from vent stream).
AFN = Abatement utilization factor of N2O abatement technology “N” (percent of time that the abatement technology is operating).
FCN = Fraction control factor of N2O abatement technology “N” (percent of total emissions from unit “z” that are sent to abatement technology “N”).
2205 = Conversion factor (lb/metric ton).
N = Number of different N2O abatement technologies with a fraction control factor.
(4)
If no N2 O abatement technologies are located after your test point, you must use the emissions factor (determined using Equation E-1 of this section) and the annual adipic acid production (determined in paragraph (f) of this section) according to Equation E-3d of this section for each adipic acid production unit.
Where:
Ed,z = Annual N2O mass emissions from adipic acid production for unit “z” according to this Equation E-3d (metric tons).
EFN2O = N2O emissions factor for unit “z” (lb N2O/ton adipic acid produced).
PZ = Annual adipic acid produced from unit “z” (tons).
2205 = Conversion factor (lb/metric ton).
(h)
You must determine the emissions for the facility by summing the unit level emissions according to Equation E-4 of this section.
Where:
Ea,z = Annual N2O mass emissions from adipic acid production unit “z” according to Equation E-3a of this section (metric tons).
Eb,z = Annual N2O mass emissions from adipic acid production unit “z” according to Equation E-3b of this section (metric tons).
Ec,z = Annual N2O mass emissions from adipic acid production unit “z” according to Equation E-3c of this section (metric tons).
Ed,z = Annual N2O mass emissions from adipic acid production unit “z” according to Equation E-3d of this section (metric tons).
M = Total number of adipic acid production units.
(i)
You must determine the amount of process N2 O emissions that is sold or transferred off site (if applicable). You can determine the amount using existing process flow meters and N2 O analyzers.