Title 40
SECTION 98.153
98.153 Calculating GHG emissions.
§ 98.153 Calculating GHG emissions.(a) The mass of HFC-23 generated from each HCFC-22 production process shall be estimated by using one of two methods, as applicable:
(1) Where the mass flow of the combined stream of HFC-23 and another reaction product (e.g., HCl) is measured, multiply the weekly (or more frequent) HFC-23 concentration measurement (which may be the average of more frequent concentration measurements) by the weekly (or more frequent) mass flow of the combined stream of HFC-23 and the other product. To estimate annual HFC-23 production, sum the weekly (or more frequent) estimates of the quantities of HFC-23 produced over the year. This calculation is summarized in Equation O-1 of this section:
Where: G23 = Mass of HFC-23 generated annually (metric tons). c23 = Fraction HFC-23 by weight in HFC-23/other product stream. Fp = Mass flow of HFC-23/other product stream during the period p (kg). p = Period over which mass flows and concentrations are measured. n = Number of concentration and flow measurement periods for the year. 10−3 = Conversion factor from kilograms to metric tons.(2) Where the mass of only a reaction product other than HFC-23 (either HCFC-22 or HCl) is measured, multiply the ratio of the weekly (or more frequent) measurement of the HFC-23 concentration and the weekly (or more frequent) measurement of the other product concentration by the weekly (or more frequent) mass produced of the other product. To estimate annual HFC-23 production, sum the weekly (or more frequent) estimates of the quantities of HFC-23 produced over the year. This calculation is summarized in Equation O-2 of this section, assuming that the other product is HCFC-22. If the other product is HCl, HCl may be substituted for HCFC-22 in Equations O-2 and O-3 of this section.
Where: G23 = Mass of HFC-23 generated annually (metric tons). c23 = Fraction HFC-23 by weight in HCFC-22/HFC-23 stream. c22 = Fraction HCFC-22 by weight in HCFC-22/HFC-23 stream. P22 = Mass of HCFC-22 produced over the period p (kg), calculated using Equation O-3 of this section. p = Period over which masses and concentrations are measured. n = Number of concentration and mass measurement periods for the year. 10−3 = Conversion factor from kilograms to metric tons.(b) The mass of HCFC-22 produced over the period p shall be estimated by using Equation O-3 of this section:
Where: P22 = Mass of HCFC-22 produced over the period p (kg). O22 = mass of HCFC-22 that is measured coming out of the Production process over the period p (kg). U22 = Mass of used HCFC-22 that is added to the production process upstream of the output measurement over the period p (kg). LF = Factor to account for the loss of HCFC-22 upstream of the measurement. The value for LF shall be determined pursuant to § 98.154(e).(c) For HCFC-22 production facilities that do not use a destruction device or that have a destruction device that is not directly connected to the HCFC-22 production equipment, HFC-23 emissions shall be estimated using Equation O-4 of this section:
Where: E23 = Mass of HFC-23 emitted annually (metric tons). G23 = Mass of HFC-23 generated annually (metric tons). S23 = Mass of HFC-23 sent off site for sale annually (metric tons). OD23 = Mass of HFC-23 sent off site for destruction (metric tons). D23 = Mass of HFC-23 destroyed on site (metric tons). I23 = Increase in HFC-23 inventory = HFC-23 in storage at end of year - HFC-23 in storage at beginning of year (metric tons).(d) For HCFC-22 production facilities that use a destruction device connected to the HCFC-22 production equipment, HFC-23 emissions shall be estimated using Equation O-5 of this section:
Where: E23 = Mass of HFC-23 emitted annually (metric tons). EL = Mass of HFC-23 emitted annually from equipment leaks, calculated using Equation O-6 of this section (metric tons). EPV = Mass of HFC-23 emitted annually from process vents, calculated using Equation O-7 of this section (metric tons). ED = Mass of HFC-23 emitted annually from destruction device (metric tons), calculated using Equation O-8 of this section.(1) The mass of HFC-23 emitted annually from equipment leaks (for use in Equation O-5 of this section) shall be estimated by using Equation O-6 of this section:
Where: EL = Mass of HFC-23 emitted annually from equipment leaks (metric tons). c23 = Fraction HFC-23 by weight in the stream(s) in the equipment. FGt = The applicable leak rate specified in Table O-1 of this subpart for each source of equipment type and service t with a screening value greater than or equal to 10,000 ppmv (kg/hr/source). NGt = The number of sources of equipment type and service t with screening values greater than or equal to 10,000 ppmv as determined according to § 98.154(i). FLt = The applicable leak rate specified in Table O-1 of this subpart for each source of equipment type and service t with a screening value of less than 10,000 ppmv (kg/hr/source). NLt = The number of sources of equipment type and service t with screening values less than 10,000 ppmv as determined according to § 98.154(j). p = One hour. n = Number of hours during the year during which equipment contained HFC-23. t = Equipment type and service as specified in Table O-1 of this subpart. 10−3 = Factor converting kg to metric tons.(2) The mass of HFC-23 emitted annually from process vents (for use in Equation O-5 of this section) shall be estimated by using Equation O-7 of this section:
Where: EPV = Mass of HFC-23 emitted annually from process vents (metric tons). ERT = The HFC-23 emission rate from the process vents during the period of the most recent test (kg/hr). PRp = The HCFC-22 production rate during the period p (kg/hr). PRT = The HCFC-22 production rate during the most recent test period (kg/hr). lp = The length of the period p (hours). 10−3 = Factor converting kg to metric tons. n = The number of periods in a year.(3) The total mass of HFC-23 emitted from destruction devices shall be estimated by using Equation O-8 of this section:
Where: ED = Mass of HFC-23 emitted annually from the destruction device (metric tons). FD = Mass of HFC-23 fed into the destruction device annually (metric tons). D23 = Mass of HFC-23 destroyed annually (metric tons).(4) For facilities that destroy HFC-23, the total mass of HFC-23 destroyed shall be estimated by using Equation O-9 of this section:
Where: D23. = Mass of HFC-23 destroyed annually (metric tons). FD = Mass of HFC-23 fed into the destruction device annually (metric tons). DE = Destruction Efficiency of the destruction device (fraction). [74 FR 56374, Oct. 30, 2009, as amended at 78 FR 71955, Nov. 29, 2013]