42.2 Definitions. As used in 42.0 of this regulation, all terms not defined herein shall have the meaning given them in the November 15, 1990 Clean Air Act Amendments (CAAA), or in 2.0 of this regulation. "Air oxidation facility" means a product recovery system and all associated air oxidation process reactors discharging directly into that system or any such reactors discharging directly into the atmosphere.
"Air oxidation process" means a reactor in which air is used as an oxidizing agent to produce an organic chemical.
"Air oxidation reactor" means any device or process vessel in which one or more organic reactants are combined with air or a combination of air and oxygen to produce one or more organic compounds. Ammoxidation and oxychlorination are included in this definition.
"Air oxidation reactor recovery train" means an individual recovery system receiving the vent stream from at least one air oxidation reactor, along with all air oxidation reactors feeding vent streams into this system.
"Product recovery system" means any equipment used to collect volatile organic compounds (VOCs) for use, reuse, or sale. Such equipment includes, but is not limited to, absorbers, adsorbers, condensers, and devices that recover non-VOCs such as ammonia and HCl.
"Synthetic organic chemical manufacturing industry" means the industry that produces, as intermediates or final products, one or more of the chemicals listed at 40 CFR 60.489 (July 1, 1992).
"Total resource effectiveness index value," or TRE index value, means a measure of the supplemental total resource requirement per unit of VOC emission reduction associated with an individual air oxidation vent stream, based on vent stream flow rate, emission rate of VOC, net heating value, and corrosive properties, as quantified by the equation given under 42.5.1 of this regulation.
"Vent stream" means any gas stream containing nitrogen that was introduced as air to the air oxidation reactor and released to the atmosphere directly from any air oxidation reactor recovery train or indirectly, after diversion through other process equipment.
42.5 Test methods and procedures. The following methods shall be used as reference methods to demonstrate compliance with 42.3 of this regulation: 42.5.1 The following equation shall be used to calculate the TRE index for a given vent stream: Click here to view Image
(42-1)
where:
TRE = The total resource effectiveness index value.
E = The measured hourly emissions in units of kilograms per hour (kg/hr).
FL = The vent stream flow rate in standard cubic meter per minute (scm/min), at a standard temperature of 20°C. For a Category E stream, the factor f(FL)0.5 should be replaced with:
Click here to view Image
where:
HT = Vent stream net heating value in units of megajoules per standard cubic meter (MJ/scm), where the net enthalpy per mole of off-gas is based on combustion at 25°C (68°F) and 760 millimeters of Mercury (mm Hg), but the standard temperature for determining the volume corresponding to one mole is 20°C, as in the definition of FL.
a, b, c, d, e, and f = Specific coefficients for six different general categories of process vent streams. The set of coefficients that apply to a given air oxidation process vent stream may be obtained from the Department.
42.5.2 Each owner or operator of an air oxidation facility seeking to comply with 42.1.2 or 42.3.3 of this regulation shall recalculate the TRE index value for that air oxidation facility whenever process changes are made. Some examples of process changes are changes in production capacity, feedstock type, or catalyst type, or whenever recovery equipment is replaced, removed, or added. The TRE index value shall be recalculated based on test data or on best engineering estimates of the effects of the change to the recovery system.42.5.3 Method 1 or 1A, as appropriate, for selection of the sampling sites. The control device inlet sampling site for determining vent stream molar composition or VOC reduction efficiency shall be prior to the inlet of the control device and after the recovery system.42.5.4 Method 2, 2A, 2C, or 2D, as appropriate, for determining the volumetric flow rates.42.5.5 The emission rate correction factor, integrated sampling, and analysis procedure of Method 3 shall be used to determine the oxygen concentration (%O2d) for determining compliance with the 20 ppmv limit. The sampling site shall be the same as that of the VOC. samples, and the samples shall be taken during the same time that the VOC samples are taken. The VOC concentration corrected to 3% O2 (Cc) shall be computed using the following equation: Click here to view Image
(42-2)
where:
Cc = Concentration of VOC corrected to 3% O2, dry basis, ppmv.
CVOC = Concentration of VOC, dry basis, ppmv.
%O2d = Concentration of O2, dry basis, percent by volume.
42.5.6 Method 18 to determine the VOC concentration in the control device outlet and the VOC concentration in the inlet when the reduction efficiency of the control device is to be determined. 42.5.6.1 The sampling time for each run shall be one hour, in which either an integrated sample or four grab samples shall be taken. If grab sampling is used, then the samples shall be taken at 15- minute intervals.42.5.6.2 The emission reduction (R) of VOC shall be determined using the following equation: Click here to view Image
(42-3)
where:
R = Emission reduction, percent by weight.
Ei = Mass rate of VOC entering the control device, kg VOC/hr.
Eo = Mass rate of VOC discharged to the atmosphere, kg VOC/hr.
42.5.6.3 The mass rates of VOC (Ei, Eo) shall be computed using the following equations: Click here to view Image
(42-4)
Click here to view Image
(42-5)
where:
Cij, Coj = Concentration of sample component J of the gas stream at the inlet and outlet of the control device, respectively.
Mij, Moj = Molecular weight of sample component J of the gas stream at the inlet and outlet of the control device, respectively, g/g-mole (lb/lb-mole).
Qi, Qo = Flow rate of gas stream at the inlet and outlet of the control device, respectively, dscm/min (dscf/hr).
K2 = Constant, 2.494x10-6(1/ppm)(g-mole/scm)(kg/g)(min/hr), where standard temperature for (g-mole/scm) is 20°C.
42.5.6.4 The VOC concentration (CVOC) is the sum of the individual components and shall be computed for each run using the following equation: Click here to view Image
(42-6)
where:
CVOC = Concentration of VOC, dry basis, ppmv.
Cj = Concentration of sample components in the sample.
n = Number of components in the sample.
42.5.7 When a flare is used to seek to comply with 42.3.2 of this regulation, the flare shall comply with the requirements of 40 CFR 60.18 (July 1, 1992).42.5.8 The test methods in Appendix A to 40 CFR Part 60 (July 1, 1992), except as provided under 40 CFR 60.8 (July 1, 1992), shall be used for determining the net heating value of the gas combusted to determine compliance under 42.3.2 of this and for determining the process vent stream TRE index value to determine compliance under 42.3.3 of this regulation.42.5.942.5.9.1 Method 1 or 1A, as appropriate, for selecting the sampling site. The sampling site for the vent stream flow rate and molar composition determination prescribed in 42.5.10 and 42.5.11 of this regulation shall be, except for the situations outlined in 42.5.9.2 of this regulation, prior to the inlet of any control device, prior to any post-reactor dilution of the stream with air, and prior to any post-reactor introduction of halogenated compounds into the vent stream. No transverse site selection method is needed for vents smaller than four inches in diameter.42.5.9.2 If any gas stream other than the air oxidation vent stream is normally conducted through the final recovery device: 42.5.9.2.1 The sampling site for vent stream flow rate and molar composition shall be prior to the final recovery device and prior to the point at which the nonair oxidation stream is introduced.42.5.9.2.2 The efficiency of the final recovery device is determined by measuring the VOC concentration using Method 18 at the inlet to the final recovery device after the introduction of any nonair oxidation vent stream and at the outlet of the final recovery device.42.5.9.2.3 This efficiency is applied to the VOC concentration measured prior to the final recovery device and prior to the introduction of the nonair oxidation stream to determine the concentration of VOC in the air oxidation stream from the final recovery device. This concentration of VOC is then used to perform the calculations outlined in 42.5.12 and 42.5.13 of this regulation.42.5.10 The molar composition of the process vent stream shall be determined as follows: 42.5.10.1 Method 18 to measure the concentration of VOC including those containing halogens.42.5.10.2 ASTM D1946-77 to measure the concentration of carbon monoxide and hydrogen.42.5.10.3 Method 4 to measure the content of water vapor.42.5.11 The volumetric flow rate shall be determined using Method 2, 2A, 2C, or 2D, as appropriate.42.5.12 The net heating value of the vent stream shall be calculated using the following equation: Click here to view Image
(42-7)
where:
HT = Net heating value of the sample, MJ/scm, where the net enthalpy per mole of off-gas is based on combustion at 25°C and 760 mm Hg, but the standard temperature for determining the volume corresponding to one mole is 20°C, as in the definition of Qs (off-gas flow rate).
K1 = Constant, 1.740x10-7
Click here to view Image
where standard temperature for
Click here to view Image
is 20°C.
Cj = Concentration of compound j in ppm, as measured for organics by Method 18 and measured for hydrogen and carbon monoxide by ASTM D1946-77 as indicated in 42.5.10 of this regulation.
Hj = Net heat of combustion of compound j, kilocalories per gram-mole (kcal/g-mole), based on combustion at 25°C and 760 mm Hg. The heats of combustion of vent stream components would be required to be determined using ASTM D2382-76 if published values are not available or cannot be calculated.
42.5.13 The emission rate of VOCs in the process vent stream shall be calculated using the following equation: Click here to view Image
(42-8)
where:
EVOC = Emission rate of VOC in the sample, kg/hr.
K2 = Constant, 2.494x10-6(1/ppm)(g-mole/scm)(kg/g)(min/hr), where standard temperature for (g-mole/scm) is 20°C.
Cj = Concentration on a dry basis of compound j in ppm as measured by Method 18 as indicated in 42.5.10 of this regulation.
Mj = Molecular weight of sample j, g/g-mole.
Qs = Vent stream flow rate (scm/min) at a standard temperature of 20°C.