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40 C.F.R. §§ 63.11925–63.11950

6 sections in range

§63.11925. What are my initial and continuous compliance requirements for process vents?

40 C.F.R. § 63.11925

Each process vent must meet the requirements of paragraphs (a) through (h) of this section.
(a)
Emission limits. Each process vent must meet the emission limits in Table 1 or 2 to this subpart prior to the vent stream being exposed to the atmosphere. The emission limits in Table 1 or 2 to this subpart apply at all times. The emission limits in Table 1 or 2 to this subpart must not be met through dilution.
(b)
Closed vent systems and control devices. Each batch process vent, continuous process vent and miscellaneous vent that is in HAP service must be routed through a closed vent system to a control device. All gas streams routed to the closed vent system and control device must be for a process purpose and not for the purpose of diluting the process vent to meet the emission limits in Table 1 or 2 to this subpart. Each control device used to comply with paragraph (a) of this section must meet the requirements of §§ 63.11925 and 63.11940, and all closed vent systems must meet the requirements in § 63.11930. You must not use a flare to comply with the emission limits in Table 1 or 2 to this subpart.
(c)
General monitoring requirements. Except as provided in paragraphs (c)(1) through (3) of this section, for each control device used to comply with the process vent emission limit specified in Table 1 or 2 to this subpart, you must install and operate a continuous parameter monitoring system (CPMS) to monitor each operating parameter specified in § 63.11940(a) through (h) to comply with your operating limit(s) required in § 63.11880(b).
(1)
Hydrogen chloride continuous emission monitoring system (CEMS). In lieu of establishing operating limits in § 63.11880(b) and using CPMS to comply with the operating limits, as specified in § 63.11940(a) through (h), upon promulgation of a performance specification for hydrogen chloride CEMS, new and existing sources have the option to install a hydrogen chloride CEMS to demonstrate initial and continuous compliance with the hydrogen chloride emission limit for process vents, as specified in paragraphs (d) and (e) of this section.
(2)
Dioxin/furan CEMS. In lieu of establishing operating limits in § 63.11880(b) and using CPMS to comply with the operating limits as specified in § 63.11940(a) through (h), upon promulgation of a performance specification for dioxin/furan CEMS, new and existing sources have the option to install a dioxin/furan CEMS to demonstrate initial and continuous compliance with the dioxins/furan emission limit for process vents, as specified in paragraphs (d) and (e) of this section.
(3)
Total hydrocarbon CEMS. In lieu of establishing operating limits in § 63.11880(b) and using CPMS to comply with the operating limits as specified in § 63.11940(a) through (h), new and existing affected sources have the option to install a total hydrocarbon CEMS to demonstrate initial and continuous compliance with the total hydrocarbons or total organic HAP emission limit for process vents, as specified in paragraphs (d) and (e) of this section.
(d)
Initial compliance. To demonstrate initial compliance with the emission limits in Table 1 or 2 to this subpart, you must comply with paragraphs (d)(1) through (5) of this section.
(1)
You must conduct an initial inspection as specified in § 63.11930(d) for each closed vent system.
(2)
For each CEMS and CPMS required or that you elect to use as specified in paragraph (c) of this section, you must prepare the quality control program and site-specific performance evaluation test plan as specified in § 63.11935(b) and site-specific monitoring plan specified in § 63.11935(c), respectively.
(3)
For each CEMS and CPMS required or that you elect to use as specified in paragraph (c) of this section, you must install, operate, and maintain the CEMS and CPMS as specified in §§ 63.11935(b) and (c), respectively, and you must conduct an initial site-specific performance evaluation test according to your site-specific monitoring plan and §§ 63.11935(b)(3) and (c)(4), respectively.
(4)
For each emission limit for which you use a CEMS to demonstrate compliance, you must meet the requirements specified in § 63.11890(c), and you must demonstrate initial compliance with the emission limits in Table 1 or 2 to this subpart based on 3-hour block averages of CEMS data collected at the minimum frequency specified in § 63.11935(b)(2) and calculated using the data reduction method specified in § 63.11935(e). For a CEMS used on a batch operation, you may use a data averaging period based on an operating block in lieu of the 3-hour averaging period.
(5)
For each emission limit in Table 1 or 2 for which you do not use a CEMS to demonstrate compliance, you must meet the requirements of paragraphs (d)(5)(i) and (ii) of this section.
(i)
You must conduct an initial performance test according to the requirements in § 63.11945 to demonstrate compliance with the total hydrocarbons or total organic HAP emission limit, vinyl chloride emission limit, hydrogen chloride emission limit, and dioxin/furan emission limit in Table 1 or 2 to this subpart.
(ii)
During the performance test specified in paragraph (d)(5)(i) of this section, for each CPMS installed and operated as specified in paragraph (c) of this section, you must establish an operating limit as the operating parameter range, minimum operating parameter level, or maximum operating parameter level specified in § 63.11935(d). You must meet the requirements specified in § 63.11890(c). Each operating limit must be based on the data averaging period for compliance specified in Table 5 to this subpart using data collected at the minimum frequency specified in § 63.11935(c)(2) and calculated using the data reduction method specified in § 63.11935(e). For a CPMS used on a batch operation, you may use a data averaging period based on an operating block in lieu of the averaging period specified in Table 5 to this subpart.
(e)
Continuous compliance. To demonstrate continuous compliance with the emission limits in Table 1 or 2 to this subpart for each process vent, you must comply with paragraphs (e)(1) through (5) of this section.
(1)
You must meet the requirements in § 63.11930 for each closed vent system.
(2)
You must operate and maintain each CEMS and CPMS required in paragraph (c) of this section as specified in § 63.11935(b) and (c), respectively.
(3)
For each emission limit for which you use a CEMS to demonstrate compliance, you must meet the requirements in paragraphs (e)(3)(i) and (ii) of this section.
(i)
You must conduct a periodic site-specific CEMS performance evaluation test according to your quality control program and site-specific performance evaluation test plan specified in § 63.11935(b)(1).
(ii)
You must demonstrate continuous compliance with the emission limits in Table 1 or 2 to this subpart based on 3-hour block averages of CEMS data collected at the minimum frequency specified in § 63.11935(b)(2), and calculated using the data reduction method specified in § 63.11935(e). You must meet the requirements specified in § 63.11890(c). For a CEMS used on a batch operation, you may use a data averaging period based on an operating block in lieu of the 3-hour averaging period.
(4)
For each emission limit for which you do not use a CEMS to demonstrate compliance, you must meet the requirements of paragraphs (e)(4)(i) and (ii) of this section.
(i)
You must conduct a performance test once every 5 years according to the requirements in § 63.11945 for each pollutant in Table 1 or 2 to this subpart.
(ii)
For each CPMS operated and maintained as specified in paragraph (e)(2) of this section, you must meet the requirements specified in paragraphs (e)(4)(ii)(A) through (C) of this section.
(A)
You must conduct periodic site-specific CPMS performance evaluation tests according to your site-specific monitoring plan and § 63.11935(c).
(B)
For each control device being monitored, you must continuously collect CPMS data consistent with § 63.11890(c) and your site-specific monitoring plan. You must continuously determine the average value of each monitored operating parameter based on the data collection and reduction methods specified in §§ 63.11935(c)(2) and 63.11935(e), and the applicable data averaging period for compliance specified in Table 5 to this subpart for all periods the process is operating. For a CPMS used on a batch operation, you may use a data averaging period based on an operating block in lieu of the averaging periods specified in Table 5 to this subpart.
(C)
You must demonstrate continuous compliance with each operating limit established in paragraph (d)(5)(ii) of this section using these average values calculated in paragraph (e)(4)(ii)(B) of this section.
(5)
Each closed vent system and control device used to comply with an emission limit in Table 1 or 2 to this subpart must be operated at all times when emissions are vented to, or collected by, these systems or devices.
(f)
To demonstrate compliance with the dioxin/furan toxic equivalency emission limit specified in Table 1 or 2 to this subpart, you must determine dioxin/furan toxic equivalency as specified in paragraphs (f)(1) through (3) of this section.
(1)
Measure the concentration of each dioxin/furan (tetra-through octachlorinated) congener emitted using Method 23 at 40 CFR part 60, appendix A-7.
(2)
For each dioxin/furan (tetra-through octachlorinated) congener measured in accordance with paragraph (f)(1) of this section, multiply the congener concentration by its corresponding toxic equivalency factor specified in Table 6 to this subpart.
(3)
Sum the products calculated in accordance with paragraph (f)(2) of this section to obtain the total concentration of dioxins/furans emitted in terms of toxic equivalency.
(g)
Emission profile. You must characterize each process vent by developing an emissions profile for each contributing continuous process vent, miscellaneous vent and batch process vent according to paragraphs (g)(1) through (3) of this section.
(1)
For batch process vents, the emissions profile must—
(i)
Describe the characteristics of the batch process vent under worst-case conditions.
(ii)
Determine emissions per episode and batch process vent emissions according to the procedures specified in § 63.11950.
(2)
For continuous process vents, the flow rate and concentration must be determined according to paragraphs (g)(2)(i) through (iii) or according to paragraph (g)(2)(iv):
(i)
(A)
Method 1 or 1A of 40 CFR part 60, appendix A-1, as appropriate, shall be used for selection of the sampling site. The sampling site shall be after the last recovery device (if any recovery devices are present) but prior to being combined with any other continuous process vent, batch process vent, or miscellaneous vent, prior to the inlet of any control device that is present and prior to release to the atmosphere.
(B)
No traverse site selection method is needed for vents smaller than 0.10 meter in diameter.
(ii)
The gas volumetric flow rate shall be determined using Method 2, 2A, 2C or 2D of 40 CFR part 60, appendix A-1, as appropriate.
(iii)
(A)
Method 18 of 40 CFR part 60, appendix A-6 or Method 25A of 40 CFR part 60, appendix A-7 shall be used to measure concentration; alternatively, any other method or data that has been validated according to the protocol in Method 301 of appendix A of this part may be used.
(B)
Where Method 18 of 40 CFR part 60, appendix A-6 is used, the following procedures shall be used to calculate parts per million by volume concentration:

(1) The minimum sampling time for each run shall be 1 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 approximately equal intervals in time, such as 15-minute intervals during the run.

(2) The concentration of either total organic compounds (TOC) (minus methane and ethane) or organic HAP shall be calculated according to paragraph (g)(2)(iii)(B)(2)(i) or (g)(2)(iii)(B)(2)(ii) of this section as applicable.

(i) The TOC concentration (CTOC) is the sum of the concentrations of the individual components and shall be computed for each run using Equation 1 of this section:

(ii) The total organic HAP concentration (CHAP) shall be computed according to Equation 1 of this section except that only the organic HAP species shall be summed. The list of organic HAP is provided in Table 2 to subpart F of this part.

(C)
Where Method 25A of 40 CFR part 60, appendix A-7 is used, the following procedures shall be used to calculate parts per million by volume TOC concentration:

(1) Method 25A of 40 CFR part 60, appendix A-7, shall be used only if a single organic HAP compound is greater than 50 percent of total organic HAP, by volume, in the vent stream.

(2) The vent stream composition may be determined by either process knowledge, test data collected using an appropriate EPA method, or a method or data validated according to the protocol in Method 301 of appendix A of this part. 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.

(3) The organic HAP used as the calibration gas for Method 25A of 40 CFR part 60, appendix A-7 shall be the single organic HAP compound present at greater than 50 percent of the total organic HAP by volume.

(4) The span value for Method 25A of 40 CFR part 60, appendix A-7 shall be 50 parts per million by volume.

(5) Use of Method 25A of 40 CFR part 60, appendix A-7 is acceptable if the response from the high-level calibration gas is at least 20 times the standard deviation of the response from the zero calibration gas when the instrument is zeroed on the most sensitive scale.

(iv)
Engineering assessment including, but not limited to, the following—
(A)
Previous test results provided the tests are representative of current operating practices at the process unit.
(B)
Bench-scale or pilot-scale test data representative of the process under representative operating conditions.
(C)
Maximum flow rate, TOC emission rate, organic HAP emission rate, or net heating value limit specified or implied within a permit limit applicable to the process vent.
(D)
Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of analytical methods include, but are not limited to:

(1) Use of material balances based on process stoichiometry to estimate maximum organic HAP concentrations,

(2) Estimation of maximum flow rate based on physical equipment design such as pump or blower capacities,

(3) Estimation of TOC or organic HAP concentrations based on saturation conditions,

(4) Estimation of maximum expected net heating value based on the vent stream concentration of each organic compound or, alternatively, as if all TOC in the vent stream were the compound with the highest heating value.

(E)
All data, assumptions, and procedures used in the engineering assessment shall be documented.
(3)
For miscellaneous process vents the emissions profile must be determined according to paragraph (g)(2)(iv) of this section.
(h)
Process changes. Except for temporary shutdowns for maintenance activities, if you make a process change such that, as a result of that change, you are subject to a different process vent limit in Table 1 or 2 to this subpart, then you must meet the requirements of § 63.11896.
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

§63.11930. What requirements must I meet for closed vent systems?

40 C.F.R. § 63.11930

(a)
General. To route emissions from process vents subject to the emission limits in Table 1 or 2 to this subpart to a control device, you must use a closed vent system and meet the requirements of this section and all provisions referenced in this section. However, if you operate and maintain your closed vent system in vacuum service as defined in § 63.12005, you must meet the requirements in paragraph (h) of this section and are not required to meet the requirements in paragraphs (a) through (g) of this section.
(b)
Collection of emissions. Each closed vent system must be designed and operated to collect the HAP vapors from each continuous process vent, miscellaneous process vent and batch process vent, and to route the collected vapors to a control device.
(c)
Bypass. For each closed vent system that contains a bypass as defined in § 63.12005 (e.g., diverting a vent stream away from the control device), you must not discharge to the atmosphere through the bypass. Any such release constitutes a violation of this rule. The use of any bypass diverted to the atmosphere during a performance test invalidates the performance test. You must comply with the provisions of either paragraph (c)(1) or (2) of this section for each closed vent system that contains a bypass that could divert a vent stream to the atmosphere.
(1)
Bypass flow indicator. Install, maintain, and operate a flow indicator as specified in paragraphs (c)(1)(i) through (iv) of this section.
(i)
The flow indicator must be properly installed at the entrance to any bypass.
(ii)
The flow indicator must be equipped with an alarm system that will alert an operator immediately, and automatically when flow is detected in the bypass. The alarm must be located such that the alert is detected and recognized easily by an operator.
(iii)
If the alarm is triggered, you must immediately initiate procedures to identify the cause of the alarm. If any closed vent system has discharged to the atmosphere through a vent or bypass, you must initiate procedures to stop the bypass discharge.
(iv)
For any instances where the flow indicator alarm is triggered, you must submit to the Administrator as part of your compliance report, the information specified in § 63.11985(b)(9) and (10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense and submit the reports specified in § 63.11985(b)(11).
(2)
Bypass valve configuration. Secure the bypass valve in the non-diverting position with a car-seal or a lock-and-key type configuration.
(i)
You must visually inspect the seal or closure mechanism at least once every month to verify that the valve is maintained in the non-diverting position, and the vent stream is not diverted through the bypass. A broken seal or closure mechanism or a diverted valve constitutes a violation from the emission limits in Table 1 or 2 to this subpart. You must maintain the records specified in paragraph (g)(1)(ii) of this section.
(ii)
For each seal or closure mechanism, you must comply with either paragraph (c)(2)(ii)(A) or (B) of this section.
(A)
For each instance that you change the bypass valve to the diverting position, you must submit to the Administrator as part of your compliance report, the information specified in § 63.11985(b)(9) and (10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense and submit the reports specified in § 63.11985(b)(11).
(B)
You must install, maintain, and operate a bypass flow indicator as specified in paragraphs (c)(1)(i) and (ii) of this section and you must meet the requirements in paragraph (c)(1)(iii) and (iv) of this section for each instance that the flow indicator alarm is triggered.
(d)
Closed vent system inspection and monitoring requirements. Except as provided in paragraph (d)(3) of this section, you must inspect each closed vent system as specified in paragraph (d)(1) or (2) of this section.
(1)
Hard-piping inspection. If the closed vent system is constructed of hard-piping, you must comply with the requirements specified in paragraphs (d)(1)(i) and (ii) of this section.
(i)
Conduct an initial inspection according to the procedures in paragraph (e) of this section.
(ii)
Conduct annual inspections for visible, audible, or olfactory indications of leaks.
(2)
Ductwork inspection. If the closed vent system is constructed of ductwork, you must conduct initial and annual inspections according to the procedures in paragraph (e) of this section.
(3)
Equipment that is unsafe to inspect. You may designate any parts of the closed vent system as unsafe to inspect if you determine that personnel would be exposed to an immediate danger as a consequence of complying with the initial and annual closed vent system inspection requirements of this subpart.
(e)
Closed vent system inspection procedures. Except as provided in paragraph (e)(4) of this section, you must comply with all provisions of paragraphs (e)(1) through (3) of this section.
(1)
General. Inspections must be performed during periods when HAP is being collected by or vented through the closed vent system. A leak is indicated by an instrument reading greater than 500 parts per million by volume above background or by visual inspection.
(2)
Inspection procedures. Each closed vent system subject to this paragraph (e)(2) must be inspected according to the procedures specified in paragraphs (e)(2)(i) through (vii) of this section.
(i)
Inspections must be conducted in accordance with Method 21 at 40 CFR part 60, appendix A-7, except as otherwise specified in this section.
(ii)
Except as provided in paragraph (e)(2)(iii) of this section, the detection instrument must meet the performance criteria of Method 21 at 40 CFR part 60, appendix A-7, except the instrument response factor criteria in section 8.1.1.2 of Method 21 must be for the representative composition of the process fluid and not of each individual volatile organic compound in the stream. For process streams that contain nitrogen, air, water or other inerts that are not organic HAP or volatile organic compound, the representative stream response factor must be determined on an inert-free basis. You may determine the response factor at any concentration for which you will monitor for leaks.
(iii)
If no instrument is available at the plant site that will meet the performance criteria of Method 21 at 40 CFR part 60, appendix A-7 specified in paragraph (e)(2)(ii) of this section, the instrument readings may be adjusted by multiplying by the representative response factor of the process fluid, calculated on an inert-free basis as described in paragraph (e)(2)(ii) of this section.
(iv)
The detection instrument must be calibrated before use on each day of its use by the procedures specified in Method 21 at 40 CFR part 60, appendix A-7.
(v)
Calibration gases must be as specified in paragraphs (e)(2)(v)(A) through (D) of this section.
(A)
Zero air (less than 10 parts per million by volume hydrocarbon in air).
(B)
Mixtures of methane in air at a concentration less than 10,000 parts per million by volume. A calibration gas other than methane in air may be used if the instrument does not respond to methane or if the instrument does not meet the performance criteria specified in paragraph (e)(2)(ii) of this section. In such cases, the calibration gas may be a mixture of one or more of the compounds to be measured in air.
(C)
If the detection instrument's design allows for multiple calibration scales, then the lower scale must be calibrated with a calibration gas that is no higher than 2,500 parts per million by volume.
(D)
Perform a calibration drift assessment, at a minimum, at the end of each monitoring day. Check the instrument using the same calibration gas(es) that were used to calibrate the instrument before use. Follow the procedures specified in Method 21 at 40 CFR part 60, appendix A-7, section 10.1, except do not adjust the meter readout to correspond to the calibration gas value. Record the instrument reading for each scale used as specified in paragraph (g)(4) of this section. Divide these readings by the initial calibration values for each scale and multiply by 100 to express the calibration drift as a percentage. If any calibration drift assessment shows a negative drift of more than 10 percent from the initial calibration value, then all equipment monitored since the last calibration with instrument readings below the appropriate leak definition and above the leak definition multiplied by the value specified in paragraph (e)(2)(v)(D)(1) of this section must be re-monitored. If any calibration drift assessment shows a positive drift of more than 10 percent from the initial calibration value, then, at your discretion, all equipment since the last calibration with instrument readings above the appropriate leak definition and below the leak definition multiplied by the value specified in paragraph (e)(2)(v)(D)(2) of this section may be re-monitored.

(1) 100 minus the percent of negative drift, divided by 100.

(2) 100 plus the percent of positive drift, divided by 100.

(vi)
You may elect to adjust or not adjust instrument readings for background. If you elect not to adjust readings for background, all such instrument readings must be compared directly to 500 parts per million by volume to determine whether there is a leak. If you elect to adjust instrument readings for background, you must measure background concentration using the procedures in this section. You must subtract the background reading from the maximum concentration indicated by the instrument.
(vii)
If you elect to adjust for background, the arithmetic difference between the maximum concentration indicated by the instrument and the background level must be compared with 500 parts per million by volume for determining whether there is a leak.
(3)
Instrument probe. The instrument probe must be traversed around all potential leak interfaces as described in Method 21 at 40 CFR part 60, appendix A-7.
(4)
Unsafe-to-inspect written plan requirements. For equipment designated as unsafe to inspect according to the provisions of paragraph (d)(3) of this section, you must maintain and follow a written plan that requires inspecting the equipment as frequently as practical during safe-to-inspect times, but not more frequently than the annual inspection schedule otherwise applicable. You must still repair unsafe-to-inspect equipment according to the procedures in paragraph (f) of this section if a leak is detected.
(f)
Closed vent system leak repair provisions. The provisions of this paragraph (f) apply to closed vent systems collecting HAP from an affected source.
(1)
Leak repair general for hard-piping. If there are visible, audible, or olfactory indications of leaks at the time of the annual visual inspections required by paragraph (d)(1)(ii) of this section, you must follow the procedure specified in either paragraph (f)(1)(i) or (ii) of this section.
(i)
You must eliminate the leak.
(ii)
You must monitor the equipment according to the procedures in paragraph (e) of this section and comply with the leak repair provisions in paragraph (f)(2) of this section.
(2)
Leak repair schedule. Leaks must be repaired as soon as practical, except as provided in paragraph (f)(3) of this section.
(i)
A first attempt at repair must be made no later than 5 days after the leak is detected.
(ii)
Except as provided in paragraph (f)(3) of this section, repairs must be completed no later than 15 days after the leak is detected or at the beginning of the next introduction of vapors to the system, whichever is later.
(3)
Delay of repair. Delay of repair of a closed vent system for which leaks have been detected is allowed if repair within 15 days after a leak is detected is technically infeasible or unsafe without a closed vent system shutdown or if you determine that emissions resulting from immediate repair would be greater than the emissions likely to result from delay of repair. Repair of such equipment must be completed as soon as practical, but not later than the end of the next closed vent system shutdown.
(g)
Closed vent system records. For closed vent systems, you must record the information specified in paragraphs (g)(1) through (5) of this section, as applicable.
(1)
Bypass records. For each closed vent system that contains a bypass that could divert a vent stream away from the control device and to the atmosphere, or cause air intrusion into the control device, you must keep a record of the information specified in either paragraph (g)(1)(i) or (ii) of this section, as applicable.
(i)
You must maintain records of any alarms triggered because flow was detected in the bypass, including the date and time the alarm was triggered, the duration of the flow in the bypass, as well as records of the times of all periods when the vent stream is diverted from the control device or the flow indicator is not operating.
(ii)
Where a seal mechanism is used to comply with paragraph (c)(2) of this section, hourly records of flow are not required. In such cases, you must record that the monthly visual inspection of the seals or closure mechanisms has been done, and must record the occurrence of all periods when the seal mechanism is broken, the bypass valve position has changed, or the key for a lock-and-key type lock has been checked out, and records of any car-seal that has been broken.
(2)
Inspection records. For each instrumental or visual inspection conducted in accordance with paragraph (d)(1) or (2) of this section for closed vent systems collecting HAP from an affected source during which no leaks are detected, you must record that the inspection was performed, the date of the inspection, and a statement that no leaks were detected.
(3)
Leak records. When a leak is detected from a closed vent system collecting HAP from an affected source, the information specified in paragraphs (g)(3)(i) through (vi) of this section must be recorded and kept for 5 years.
(i)
The instrument and the equipment identification number and the operator name, initials, or identification number.
(ii)
The date the leak was detected and the date of the first attempt to repair the leak.
(iii)
The date of successful repair of the leak.
(iv)
The maximum instrument reading measured by the procedures in paragraph (e) of this section after the leak is successfully repaired.
(v)
Repair delayed and the reason for the delay if a leak is not repaired within 15 days after discovery of the leak. You may develop a written procedure that identifies the conditions that justify a delay of repair. In such cases, reasons for delay of repair may be documented by citing the relevant sections of the written procedure.
(vi)
Copies of the compliance reports as specified in § 63.11985(b)(9), if records are not maintained on a computerized database capable of generating summary reports from the records.
(4)
Instrument calibration records. You must maintain records of the information specified in paragraphs (g)(4)(i) through (vi) of this section for monitoring instrument calibrations conducted according to sections 8.1.2 and 10 of Method 21 at 40 CFR part 60, appendix A-7, and paragraph (e) of this section.
(i)
Date of calibration and initials of operator performing the calibration.
(ii)
Calibration gas cylinder identification, certification date, and certified concentration.
(iii)
Instrument scale(s) used.
(iv)
A description of any corrective action taken if the meter readout could not be adjusted to correspond to the calibration gas value in accordance with section 10.1 of Method 21 at 40 CFR part 60, appendix A-7.
(v)
Results of each calibration drift assessment required by paragraph (e)(2)(v)(D) of this section (i.e., instrument reading for calibration at end of the monitoring day and the calculated percent difference from the initial calibration value).
(vi)
If you make your own calibration gas, a description of the procedure used.
(5)
Unsafe-to-inspect records. If you designate equipment as unsafe-to-inspect as specified in paragraph (d)(3) of this section, you must keep the records specified in paragraph (g)(5)(i) and (ii) of this section.
(i)
You must maintain the identity of unsafe-to-inspect equipment as specified in paragraph (d)(3) of this section.
(ii)
You must keep a written plan for inspecting unsafe-to-inspect equipment as required by paragraph (e)(4) of this section and record all activities performed according to the written plan.
(h)
Closed vent systems in vacuum service. If you operate and maintain a closed vent system in vacuum service as defined in § 63.12005, you must comply with the requirements in paragraphs (h)(1) through (3) of this section, and you are not required to comply with any other provisions of this section. Any incidence where a closed vent system designed to be in vacuum service is operating and not in vacuum service constitutes a violation of this rule, unless the closed vent system is meeting the requirements in paragraphs (a) through (g) of this section for closed vent systems that are not in vacuum service. Any such incidence during a performance test invalidates the performance test.
(1)
In vacuum service alarm. You must install, maintain, and operate a pressure gauge and alarm system that will alert an operator immediately and automatically when the pressure is such that the closed vent system no longer meets the definition of in vacuum service as defined in § 63.12005. The alarm must be located such that the alert is detected and recognized easily by an operator.
(2)
In vacuum service alarm procedures. If the alarm is triggered for a closed vent system operating in vacuum service as specified in paragraph (h)(1) of this section, you must immediately initiate procedures to identify the cause of the alarm. If the closed vent system is not in vacuum service, you must initiate procedures to get the closed vent system back in vacuum service as defined in § 63.12005, or you must immediately comply with the requirements in paragraphs (a) through (g) of this section for closed vent systems that are not in vacuum service.
(3)
In vacuum service alarm records and reports. For any incidences where a closed vent system designed to be in vacuum service is not in vacuum service, you must submit to the Administrator as part of your compliance report, the information specified in § 63.11985(b)(10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense and submit the reports specified in § 63.11985(b)(11).
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

§63.11935. What CEMS and CPMS requirements must I meet to demonstrate initial and continuous compliance with the emission standards for process vents?

40 C.F.R. § 63.11935

(a)
General requirements for CEMS and CPMS. You must meet the requirements in paragraph (b) of this section for each CEMS specified in § 63.11925(c) used to demonstrate compliance with the emission limits for process vents in Table 1 or 2 to this subpart. You must meet the CPMS requirements in paragraph (c) of this section and establish your operating limits in paragraph (d) of this section for each operating parameter specified in Table 5 to this subpart for each process vent control device specified in § 63.11925(b) that is used to comply with the emission limits for process vents in Table 1 or 2 to this subpart, except that flow indicators specified in § 63.11940(a) are not subject to the requirements of this section.
(b)
CEMS. You must install, operate, and maintain each CEMS according to paragraphs (b)(1) through (7) of this section and continuously monitor emissions.
(1)
You must prepare your quality control program and site-specific performance evaluation test plan, as specified in § 63.8(d) and (e). You must submit your performance evaluation test plan to the Administrator for approval, as specified in § 63.8(e)(3).
(2)
The monitoring equipment must be capable of providing a continuous record, recording data at least once every 15 minutes.
(3)
You must conduct initial and periodic site-specific performance evaluations and any required tests of each CEMS according to your quality control program and site-specific performance evaluation test plan prepared as specified in § 63.8(d) and (e).
(4)
If supplemental gases are added to the control device, you must correct the measured concentrations in accordance with § 63.11945(d)(3).
(5)
You must operate and maintain the CEMS in continuous operation according to the quality control program and performance evaluation test plan. CEMS must record data at least once every 15 minutes.
(6)
CEMS must meet the minimum accuracy and calibration frequency requirements specified in the performance specifications specified in paragraphs (b)(6)(i) and (ii) of this section, as applicable.
(i)
A hydrogen chloride or dioxin/furan CEMS must meet the requirements of the promulgated performance specification for the CEMS.
(ii)
A total hydrocarbon CEMS must meet the requirements of 40 CFR Part 60, Appendix B, performance specification 8A.
(7)
Before commencing or ceasing use of a CEMS system, you must notify the Administrator as specified in paragraphs (b)(7)(i) and (ii) of this section.
(i)
You must notify the Administrator 1 month before starting use of the continuous emissions monitoring system.
(ii)
You must notify the Administrator 1 month before stopping use of the continuous emissions monitoring system, in which case you must also conduct a performance test within 60 days of ceasing operation of the system.
(c)
CPMS. You must install, maintain, and operate each CPMS as specified in paragraphs (c)(1) through (6) of this section and continuously monitor operating parameters.
(1)
As part of your quality control program and site-specific performance evaluation test plan prepared as specified in § 63.8(d) and (e), you must prepare a site-specific monitoring plan that addresses the monitoring system design, data collection, and the quality assurance and quality control elements specified in paragraphs (c)(1)(i) through (v) of this section and § 63.8(d). You are not required to submit the plan for approval unless requested by the Administrator. You may request approval of monitoring system quality assurance and quality control procedure alternatives to those specified in paragraphs (c)(1)(i) through (v) of this section in your site-specific monitoring plan.
(i)
The performance criteria and design specifications for the monitoring system equipment, including the sample interface, detector signal analyzer, and data acquisition and calculations.
(ii)
Sampling interface (e.g., thermocouple) location such that the monitoring system will provide representative measurements.
(iii)
Equipment performance checks, calibrations, or other audit procedures.
(iv)
Ongoing operation and maintenance procedures in accordance with provisions in § 63.8(c)(1) and (3).
(v)
Ongoing reporting and recordkeeping procedures in accordance with provisions in § 63.10(c), (e)(1) and (e)(2)(i).
(2)
The monitoring equipment must be capable of providing a continuous record, recording data at least once every 15 minutes.
(3)
You must install, operate, and maintain each CPMS according to the procedures and requirements in your site-specific monitoring plan.
(4)
You must conduct an initial and periodic site-specific performance evaluation tests of each CPMS according to your site-specific monitoring plan.
(5)
All CPMS must meet the specific parameter (e.g., minimum accuracy and calibration frequency) requirements specified in § 63.11940 and Table 7 to this subpart.
(6)
Monitoring equipment for temperature, pressure, volumetric flow rate, mass flow rate and conductivity must be capable of measuring the appropriate parameter over a range that extends at least 20 percent beyond the normal expected operating range of values for that parameter. The data recording system associated with affected CPMS must have a resolution that is equal to or better than one-half of the required system accuracy.
(d)
Establish operating limit. For each operating parameter that must be monitored in § 63.11925(c) for process vent control devices, you must establish an operating limit as specified in paragraphs (d)(1) through (4) of this section. You must establish each operating limit as an operating parameter range, minimum operating parameter level, or maximum operating parameter level as specified in Table 7 to this subpart. Where this subpart does not specify which format to use for your operating limit (e.g., operating range or minimum operating level), you must determine which format is best to establish proper operation of the control device such that you are meeting the emission limits specified in Table 1 or 2 to this subpart.
(1)
For process vent control devices, the operating limit established for each monitored parameter specified in § 63.11940 must be based on the operating parameter values recorded during any performance test conducted to demonstrate compliance as required by § 63.11925(d)(4) and (e)(4) and may be supplemented by engineering assessments and/or manufacturer's recommendations. You are not required to conduct performance tests over the entire range of allowed operating parameter values. The established operating limit must represent the conditions for which the control device is meeting the emission limits specified in Table 1 or 2 to this subpart.
(2)
You must include as part of the notification of compliance status or the operating permit application or amendment, the information in paragraphs (d)(2)(i) through (iv) of this section, as applicable, for each process vent control device requiring operating limits.
(i)
Descriptions of monitoring devices, monitoring frequencies and operating scenarios.
(ii)
The established operating limit of the monitored parameter(s).
(iii)
The rationale for the established operating limit, including any data and calculations used to develop the operating limit and a description of why the operating limit indicates proper operation of the control device.
(iv)
The rationale used to determine which format to use for your operating limit (e.g., operating range, minimum operating level or maximum operating level), where this subpart does not specify which format to use.
(3)
For batch processes, you may establish operating limits for individual batch emission episodes, including each distinct episode of process vent emissions or each individual type of batch process that generates wastewater, if applicable. You must provide rationale in a batch precompliance report as specified in § 63.11985(c)(2) instead of the notification of compliance status for the established operating limit. You must include any data and calculations used to develop the operating limits and a description of why each operating limit indicates proper operation of the control device during the specific batch emission episode.
(4)
If you elect to establish separate operating limits for different batch emission episodes within a batch process as specified in paragraph (d)(3) of this section, you must maintain daily records indicating each point at which you change from one operating limit to another, even if the monitoring duration for an operating limit is less than 15 minutes. You must maintain a daily record according to § 63.11990(e)(4)(i).
(e)
Reduction of CPMS and CEMS data. You must reduce CEMS and CPMS data to 1-hour averages according to § 63.8(g) to compute the average values for demonstrating compliance specified in §§ 63.11925(e)(3)(ii), 63.11925(e)(4)(ii)(B), and 63.11960(c)(2) for CEMS and CPMS, as applicable.
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

§63.11940. What continuous monitoring requirements must I meet for control devices required to install CPMS to meet the emission limits for process vents?

40 C.F.R. § 63.11940

As required in § 63.11925(c), you must install and operate the applicable CPMS specified in paragraphs (a) through (g) of this section for each control device you use to comply with the emission limits for process vents in Table 1 or 2 to this subpart. You must monitor, record, and calculate CPMS data averages as specified in Table 7 to this subpart. Paragraph (h) of this section provides an option to propose alternative monitoring parameters or procedures.
(a)
Flow indicator. If flow to a control device could be intermittent, you must install, calibrate, and operate a flow indicator at the inlet or outlet of the control device to identify periods of no flow.
(b)
Thermal oxidizer monitoring. If you are using a thermal oxidizer to meet an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must equip the thermal oxidizer with the monitoring equipment specified in paragraphs (b)(1) through (3) of this section, as applicable.
(1)
If a thermal oxidizer other than a catalytic thermal oxidizer is used, you must install a temperature monitoring device in the fire box or in the ductwork immediately downstream of the fire box in a position before any substantial heat exchange occurs.
(2)
Except as provided in paragraph (b)(3) of this section, where a catalytic thermal oxidizer is used, you must install temperature monitoring devices in the gas stream immediately before and after the catalyst bed. You must monitor the temperature differential across the catalyst bed.
(3)
Instead of complying with paragraph (b)(2) of this section, and if the temperature differential between the inlet and outlet of the catalytic thermal oxidizer during normal operating conditions is less than 10 degrees Celsius (18 degrees Fahrenheit), you may elect to monitor the inlet temperature and conduct catalyst checks as specified in paragraphs (b)(3)(i) and (ii) of this section.
(i)
You must conduct annual sampling and analysis of the catalyst activity (i.e., conversion efficiency) following the manufacturer's or catalyst supplier's recommended procedures. If problems are found during the catalyst activity test, you must replace the catalyst bed or take other corrective action consistent with the manufacturer's recommendations within 15 days or by the next time any process vent stream is collected by the control device, whichever is sooner.
(ii)
You must conduct annual internal inspections of the catalyst bed to check for fouling, plugging, or mechanical breakdown. You must also inspect the bed for channeling, abrasion, and settling. If problems are found during the annual internal inspection of the catalyst, you must replace the catalyst bed or take other corrective action consistent with the manufacturer's recommendations within 15 days or by the next time any process vent stream is collected by the control device, whichever is later. If the catalyst bed is replaced and is not of like or better kind and quality as the old catalyst then you must conduct a new performance test according to § 63.11945 to determine destruction efficiency. If a catalyst bed is replaced and the replacement catalyst is of like or better kind and quality as the old catalyst, then a new performance test to determine destruction efficiency is not required.
(c)
Absorber and acid gas scrubber monitoring. If you are using an absorber or acid gas scrubber to meet an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must install the monitoring equipment specified in paragraphs (c)(1) through (3) of this section.
(1)
Install and operate the monitoring equipment as specified in either paragraph (c)(1)(i) or (ii) of this section.
(i)
A flow meter to monitor the absorber or acid gas scrubber influent liquid flow.
(ii)
A flow meter to monitor the absorber or acid gas scrubber influent liquid flow and the gas stream flow using one of the procedures specified in paragraphs (c)(1)(ii)(A), (B), or (C) of this section. You must monitor the liquid-to-gas ratio determined by dividing the flow rate of the absorber or acid gas scrubber influent by the gas flow rate. The units of measure must be consistent with those used to calculate this ratio during the performance test.
(A)
Determine gas stream flow using the design blower capacity, with appropriate adjustments for pressure drop.
(B)
Measure the gas stream flow at the absorber or acid gas scrubber inlet.
(C)
If you have previously determined compliance for a scrubber that requires a determination of the liquid-to-gas ratio, you may use the results of that test provided the test conditions are representative of current operation.
(2)
Install and operate the monitoring equipment as specified in either paragraph (c)(2)(i), (ii), or (iii) of this section.
(i)
Install and operate pressure gauges at the inlet and outlet of the absorber or acid gas scrubber to monitor the pressure drop through the absorber or acid gas scrubber.
(ii)
If the difference in the inlet gas stream temperature and the inlet liquid stream temperature is greater than 38 degrees Celsius, you may install and operate a temperature monitoring device at the scrubber gas stream exit.
(iii)
If the difference between the specific gravity of the scrubber effluent scrubbing fluid and specific gravity of the scrubber inlet scrubbing fluid is greater than or equal to 0.02 specific gravity units, you may install and operate a specific gravity monitoring device on the inlet and outlet of the scrubber.
(3)
If the scrubbing liquid is a reactant (e.g., lime, ammonia hydroxide), you must install and operate one of the devices listed in either paragraph (c)(3)(i), (ii) or (iii) of this section.
(i)
A pH monitoring device to monitor the pH of the scrubber liquid effluent.
(ii)
A caustic strength monitoring device to monitor the caustic strength of the scrubber liquid effluent.
(iii)
A conductivity monitoring device to monitor the conductivity of the scrubber liquid effluent.
(d)
Regenerative adsorber monitoring. If you are using a regenerative adsorber to meet an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must install and operate the applicable monitoring equipment listed in paragraphs (d)(1) through (5) of this section, and comply with the requirements in paragraphs (d)(6) and (7) of this section. If the adsorption system water is wastewater as defined in § 63.12005, then it is subject to the requirements of § 63.11965.
(1)
For non-vacuum regeneration systems, an integrating regeneration stream flow monitoring device having an accuracy of ±10 percent, capable of recording the total regeneration stream mass for each regeneration cycle. For non-vacuum regeneration systems, an integrating regeneration stream flow monitoring device capable of continuously recording the total regeneration stream mass flow for each regeneration cycle.
(2)
For non-vacuum regeneration systems, an adsorber bed temperature monitoring device, capable of continuously recording the adsorber bed temperature after each regeneration and within 15 minutes of completing any temperature regulation (cooling or warming to bring bed temperature closer to vent gas temperature) portion of the regeneration cycle.
(3)
For non-vacuum and non-steam regeneration systems, an adsorber bed temperature monitoring device capable of continuously recording the bed temperature during regeneration, except during any temperature regulating (cooling or warming to bring bed temperature closer to vent gas temperature) portion of the regeneration cycle.
(4)
For a vacuum regeneration system, a pressure transmitter installed in the vacuum pump suction line capable of continuously recording the vacuum level for each minute during regeneration. You must establish a minimum target and a length of time at which the vacuum must be below the minimum target during regeneration.
(5)
A device capable of monitoring the regeneration frequency (i.e., operating time since last regeneration) and duration.
(6)
You must perform a verification of the adsorber during each day of operation. The verification must be through visual observation or through an automated alarm or shutdown system that monitors and records system operational parameters. The verification must verify that the adsorber is operating with proper valve sequencing and cycle time.
(7)
You must conduct weekly measurements of the carbon bed outlet volatile organic compounds concentration over the last 5 minutes of an adsorption cycle for each carbon bed. For regeneration cycles longer than 1 week, you must perform the measurement over the last 5 minutes of each adsorption cycle for each carbon bed. The outlet concentration of volatile organic compounds must be measured using a portable analyzer, in accordance with Method 21 at 40 CFR part 60, appendix A-7, for open-ended lines. Alternatively, outlet concentration of HAP(s) may be measured using chromatographic analysis using Method 18 at 40 CFR part 60, appendix A-6.
(e)
Non-regenerative adsorber monitoring. If you are using a non-regenerative adsorber, or canister type system that is sent off site for regeneration or disposal, to meet an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must install a system of dual adsorber units in series and conduct the monitoring and bed replacement as specified in paragraphs (e)(1) through (4) of this section.
(1)
Establish the average adsorber bed life by conducting daily monitoring of the outlet volatile organic compound or HAP concentration, as specified in this paragraph (e)(1), of the first adsorber bed in series until breakthrough occurs for the first three adsorber bed change-outs. The outlet concentration of volatile organic compounds must be measured using a portable analyzer, in accordance with Method 21 at 40 CFR part 60, appendix A-7, for open-ended lines. Alternatively, outlet concentration of HAP may be measured using chromatographic analysis using Method 18 at 40 CFR part 60, appendix A-6. Breakthrough of the bed is defined as the time when the level of HAP detected is at the highest concentration allowed to be discharged from the adsorber system.
(2)
Once the average life of the bed is determined, conduct ongoing monitoring as specified in paragraphs (e)(2)(i) through (iii) of this section.
(i)
Except as provided in paragraphs (e)(2)(ii) and (iii) of this section, conduct daily monitoring of the adsorber bed outlet volatile organic compound or HAP concentration, as specified in paragraph (e)(1) of this section.
(ii)
You may conduct monthly monitoring if the adsorbent has more than 2 months of life remaining, as determined by the average primary adsorber bed life, established in paragraph (e)(1) of this section, and the date the adsorbent was last replaced.
(iii)
You may conduct weekly monitoring if the adsorbent has more than 2 weeks of life remaining, as determined by the average primary adsorber bed life, established in paragraph (e)(1) of this section, and the date the adsorbent was last replaced.
(3)
The first adsorber in series must be replaced immediately when breakthrough is detected between the first and second adsorber. The original second adsorber (or a fresh canister) will become the new first adsorber and a fresh adsorber will become the second adsorber. For purposes of this paragraph (e)(3), “immediately” means within 8 hours of the detection of a breakthrough for adsorbers of 55 gallons or less, and within 24 hours of the detection of a breakthrough for adsorbers greater than 55 gallons.
(4)
In lieu of replacing the first adsorber immediately, you may elect to monitor the outlet of the second canister beginning on the day the breakthrough between the first and second canister is identified and each day thereafter. This daily monitoring must continue until the first canister is replaced. If the constituent being monitored is detected at the outlet of the second canister during this period of daily monitoring, both canisters must be replaced within 8 hours of the time of detection of volatile organic compounds or HAP at 90 percent of the allowed level (90 percent of breakthrough definition).
(f)
Condenser monitoring. If you are using a condenser to meet an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must install and operate a condenser exit gas temperature monitoring device.
(g)
Other control devices. If you use a control device other than those listed in this subpart to comply with an emission limit in Table 1 or 2 to this subpart and you are required to use CPMS as specified in § 63.11925(c), you must comply with the requirements as specified in paragraphs (g)(1) and (2) of this section.
(1)
Submit a description of the planned monitoring, recordkeeping, and reporting procedures. The Administrator will approve, deny or modify the proposed monitoring, reporting and recordkeeping requirements as part of the review of the plan or through the review of the permit application or by other appropriate means.
(2)
You must establish operating limits for monitored parameters that are approved by the Administrator. To establish the operating limit, the information required in § 63.11935(d) must be submitted in the notification of compliance status report specified in § 63.11985(a).
(h)
Alternatives to monitoring requirements.
(1)
You may request approval to use alternatives to the continuous operating parameter monitoring listed in this section, as specified in §§ 63.11985(c)(4) and 63.8.
(2)
You may request approval to monitor a different parameter than those established in § 63.11935(d) or to set unique monitoring parameters, as specified in §§ 63.11985(c)(5) and 63.8. Until permission to use an alternative monitoring parameter has been granted by the Administrator, you remain subject to the requirements of this subpart.
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

§63.11945. What performance testing requirements must I meet for process vents?

40 C.F.R. § 63.11945

(a)
General. For each control device used to meet the emission limits for process vents in Table 1 or 2 to this subpart, you must conduct the initial and periodic performance tests required in § 63.11925(d) and (e) and as specified in § 63.11896 using the applicable test methods and procedures specified in Table 8 to this subpart and paragraphs (b) through (d) of this section.
(b)
Process operating conditions. You must conduct performance tests under the conditions specified in paragraphs (b)(1) through (3) of this section, as applicable. Upon request, the owner or operator shall make available to the Administrator such records as may be necessary to determine the conditions of performance tests. In all cases, a site-specific plan must be submitted to the Administrator for approval prior to testing in accordance with § 63.7(c). The test plan must include the emission profiles described in § 63.11925(g).
(1)
Continuous process vents. For continuous process vents, you must conduct all performance tests at maximum representative operating conditions for the process. For continuous compliance, you must conduct subsequent performance tests within the range of operating limit(s) that were established for the control device during the initial or subsequent performance tests specified in § 63.11925(d) and (e). If an operating limit is a range, then you must conduct subsequent performance tests within the range of maximum or minimum operating limits for the control device, which result in highest emissions (i.e., lowest emission reduction).
(2)
Batch process operations. Testing must be conducted at absolute worst-case conditions or hypothetical worst-case conditions as specified in paragraph (c) of this section.
(3)
Combination of both continuous and batch unit operations. You must conduct performance tests when the batch process vents are operating at absolute worst-case conditions or hypothetical worst-case conditions, as specified in paragraphs (c)(1) and (2) of this section, and at maximum representative operating conditions for the process. For continuous compliance, you must operate the control device as close as possible to your operating limit(s) for the control device established during the initial or subsequent performance tests specified in § 63.11925 (d) and (e). If an operating limit is a range, then you must operate the control device as close as possible to the maximum or minimum operating limit for the control device, whichever results in higher emissions (i.e., lower emission reduction), unless the Administrator specifies or approves alternate operating conditions.
(c)
Batch worst-case conditions. The absolute worst-case conditions for batch process operations must be characterized by the criteria presented in paragraph (c)(1) of this section. The hypothetical worst-case conditions for batch process operations must be characterized by the criteria presented in paragraph (c)(2) of this section.
(1)
Absolute worst-case conditions. For batch process operations, absolute worst-case conditions are defined by the criteria presented in paragraph (c)(1)(i) of this section if the maximum load is the most challenging condition for the control device. Otherwise, absolute worst-case conditions are defined by the conditions in paragraph (c)(1)(ii) of this section. You must consider all relevant factors, including load and compound-specific characteristics in defining absolute worst-case conditions.
(i)
A 1-hour period of time in which the inlet to the control device contains the highest HAP mass loading rate, in pounds per hour, capable of being vented to the control device. An emission profile as described in § 63.11925(g) must be used to identify the 1-hour period of maximum HAP loading.
(ii)
The period of time when the HAP loading or stream composition (including non-HAP) is most challenging for the control device. These conditions include, but are not limited to the following:
(A)
Periods when the stream contains the highest combined organic load, in pounds per hour, described by the emission profiles in § 63.11925(g).
(B)
Periods when the streams contain HAP constituents that approach limits of solubility for scrubbing media.
(C)
Periods when the streams contain HAP constituents that approach limits of adsorptivity for adsorption systems.
(2)
Hypothetical worst-case conditions. For batch process operations, hypothetical worst-case conditions are simulated test conditions that, at a minimum, contain the highest hourly HAP load of emissions that would be predicted to be vented to the control device based on the emissions profiles described in paragraphs (c)(3)(ii) or (iii) of this section.
(3)
Emission profile. For batch process operations, you must develop an emission profile for the vent to the control device that describes the characteristics of the vent stream at the inlet to the control device under worst-case conditions. The emission profile must be developed based on any one of the procedures described in paragraphs (c)(3)(i) through (iii) of this section.
(i)
Emission profile by process. The emission profile must consider all batch emission episodes that could contribute to the vent stack for a period of time that is sufficient to include all processes venting to the stack and must consider production scheduling. The profile must describe the HAP load to the device that equals the highest sum of emissions from the episodes that can vent to the control device in any given hour. Emissions per episode must be calculated using the procedures specified in § 63.11950. Emissions per episode must be divided by the duration of the episode only if the duration of the episode is longer than 1 hour.
(ii)
Emission profile by equipment. The emission profile must consist of emissions that meet or exceed the highest emissions, in pounds per hour that would be expected under actual processing conditions. The profile must describe equipment configurations used to generate the emission events, volatility of materials processed in the equipment, and the rationale used to identify and characterize the emission events. The emissions may be based on using a compound more volatile than compounds actually used in the process(es), and the emissions may be generated from all equipment in the process(es) or only selected equipment.
(iii)
Emission profile by capture and control device limitation. The emission profile must consider the capture and control system limitations and the highest emissions, in pounds per hour that can be routed to the control device, based on maximum flow rate and concentrations possible because of limitations on conveyance and control equipment (e.g., fans and lower explosive level alarms).
(d)
Concentration correction calculation. If a combustion device is the control device and supplemental combustion air is used to combust the emissions, the concentration of total hydrocarbons, total organic HAP, vinyl chloride, and hydrogen chloride must be corrected as specified in paragraph (d)(1) or (2) of this section. If a control device other than a combustion device is used to comply with an outlet concentration emission limit for batch process vents, you must correct the actual concentration for supplemental gases as specified in paragraph (d)(3) of this section.
(1)
Determine the concentration of total hydrocarbons, total organic HAP, vinyl chloride, or hydrogen chloride corrected to 3-percent oxygen (Cc) using Equation 1 of this section.
(2)
To determine the oxygen concentration, you must use the emission rate correction factor (or excess air), integrated sampling and analysis procedures of Method 3, 3A, or 3B at 40 CFR part 60, appendix A-2, or ANSI/ASME PTC 19.10-1981 (incorporated by reference, see § 63.14).
(3)
Correct the measured concentration for supplemental gases using Equation 2 of this section. Process knowledge and representative operating data may be used to determine the fraction of the total flow due to supplemental gas.
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

§63.11950. What emissions calculations must I use for an emission profile?

40 C.F.R. § 63.11950

When developing your emission profiles for batch process vents as required in § 63.11925(g), except as specified in paragraph (i) of this section, you must calculate emissions from episodes caused by vapor displacement, purging a partially filled vessel, heating, depressurization, vacuum operations, gas evolution, air drying, or empty vessel purging, using the applicable procedures in paragraphs (a) through (h) of this section.
(a)
Vapor displacement. You must calculate emissions from vapor displacement due to transfer of material using Equation 1 of this section.

(Eq. 1)

(b)
Gas sweep of a partially filled vessel. You must calculate emissions from purging a partially filled vessel using Equation 2 of this section. The pressure of the vessel vapor space may be set equal to 760 millimeters of mercury (mmHg). You must multiply the HAP partial pressure in Equation 2 of this section by a HAP-specific saturation factor determined in accordance with Equations 3 through 5 of this section. Solve Equation 3 of this section iteratively beginning with saturation factors (in the right-hand side of the equation) of 1.0 for each condensable compound. Stop iterating when the calculated saturation factors for all compounds are the same to two significant figures for subsequent iterations. Note that for multi-component emission streams, saturation factors must be calculated for all condensable compounds, not just the HAP.

(Eq. 2)

(c)
Heating. You must calculate emissions caused by the heating of a vessel to a temperature lower than the boiling point using the procedures in paragraph (c)(1) of this section. If the contents of a vessel are heated to the boiling point, you must calculate emissions using the procedures in paragraph (c)(2) of this section.
(1)
If the final temperature to which the vessel contents are heated is lower than the boiling point of the HAP in the vessel, you must calculate the mass of HAP emitted per episode using Equation 6 of this section. The average gas space molar volume during the heating process is calculated using Equation 7 of this section. The difference in the number of moles of condensable in the vessel headspace between the initial and final temperatures is calculated using Equation 8 of this section.

(Eq. 6)

(2)
If the final temperature to which the vessel contents are heated is at the boiling point or higher, you must calculate emissions using the procedure in paragraphs (c)(2)(i) and (ii) of this section.
(i)
To calculate the emissions from heating to the boiling point use Equations 9, 10 and 11 of this section. (Note that Pa2 = 0 in the calculation of Δη in Equation 10 of this section.)
(ii)
While boiling, the vessel must be operated with a properly operated process condenser. An initial demonstration that a process condenser is properly operated must be conducted during the boiling operation and documented in the notification of compliance status report described in § 63.11985(a). You must either measure the liquid temperature in the receiver or the temperature of the gas stream exiting the condenser and show it is less than the boiling or bubble point of the HAP in the vessel; or perform a material balance around the vessel and condenser and show that at least 99 percent of the recovered HAP vaporized while boiling is condensed. This demonstration is not required if the process condenser is followed by a condenser acting as a control device or if the control device is monitored using a CEMS.
(d)
Depressurization. You must calculate emissions from depressurization using Equation 12 of this section.
(e)
Vacuum systems. You must calculate emissions from vacuum systems using Equation 13 of this section if the air leakage rate is known or can be approximated. The receiving vessel is part of the vacuum system for purposes of this subpart.
(h)
Empty vessel purging. You must calculate emissions from empty vessel purging using Equation 15 of this section (Note: The term e-Ft/v can be assumed to be 0):
(i)
Engineering assessments. You must conduct an engineering assessment to calculate HAP emissions or emission episodes from each process vent that are not due to vapor displacement, partially filled vessel purging, heating, depressurization, vacuum operations, gas evolution, air drying or empty vessel purging. An engineering assessment may also be used to support a finding that the emissions estimation equations in this section are inappropriate. All data, assumptions and procedures used in the engineering assessment must be documented, are subject to preapproval by the Administrator, and must be reported in the batch precompliance report. An engineering assessment should include, but is not limited to, the items listed in paragraphs (i)(1) through (4) of this section.
(1)
Previous test results provided the tests are representative of current operating practices at the process unit.
(2)
Bench-scale or pilot-scale test data representative of the process under representative operating conditions.
(3)
Maximum flow rate, HAP emission rate, concentration, or other relevant parameter specified or implied within a permit limit applicable to the process vent.
(4)
Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of analytical methods include, but are not limited to the following:
(i)
Use of material balances based on process stoichiometry to estimate maximum organic HAP concentrations.
(ii)
Estimation of maximum flow rate based on physical equipment design such as pump or blower capacities.
(iii)
Estimation of HAP concentrations based on saturation conditions.
Notes, amendments, and revision history

Source

Source: 77 FR 22906, Apr. 17, 2012, unless otherwise noted.

Authority

Authority: 42 U.S.C. 7401 et seq.

Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.