NR 440.684(7)(a)(a) The owner or operator subject to the provisions of sub. (3) (a) or (b) shall install, calibrate, maintain and operate monitoring devices or perform measurements to determine the following operations information on a daily basis: NR 440.684(7)(a)1.1. The accumulation of sulfur product over each 24-hour period: The monitoring method may incorporate the use of an instrument to measure and record the liquid sulfur production rate, or may be a procedure for measuring and recording the sulfur liquid levels in the storage tanks with a level indicator or by manual soundings with subsequent calculation of the sulfur production rate based on the tank geometry, stored sulfur density, and elapsed time between readings. The method shall be designed to be accurate with ± 2% of the 24-hour sulfur accumulation. NR 440.684(7)(a)2.2. The H2S concentration in the acid gas from the sweetening unit for each 24-hour period: At least one sample per 24-hour period shall be collected and analyzed using the method specified in sub. (5) (b) 3. The department may require the owner or operator to demonstrate that the H2S concentration obtained from one or more samples over a 24-hour period is within ± 20% of the average of 12 samples collected at equally spaced intervals during the 24-hour period. In instances where the H2S concentration of a single sample is not within ± 20% of the average of the 12 equally spaced samples, the department may require a more frequent sampling schedule. NR 440.684(7)(a)3.3. The average acid gas flow rate from the sweetening unit: The owner or operator shall install and operate a monitoring device to continuously measure the flow rate of acid gas. The monitoring device reading shall be recorded at least once per hour during each 24-hour period. The average acid gas flow rate shall be computed from the individual readings. NR 440.684(7)(a)5.5. The required sulfur dioxide emission reduction efficiency for the 24-hour period. The sulfur feed rate and the H2S concentration in the acid gas for the 24-hour period as applicable, shall be used to determine the required efficiency in accordance with the provisions of sub. (3) (b). NR 440.684(7)(b)(b) Where compliance is achieved through the use of an oxidation control system or a reduction control system followed by a continually operated incineration device, the owner or operator shall install, calibrate, maintain, and operate monitoring devices and continuous emission monitors as follows: NR 440.684(7)(b)1.1. A continuous monitoring system to measure the total sulfur emission rate (E) of SO2 in the gases discharged to the atmosphere. The SO2 emission rate shall be expressed in terms of equivalent sulfur mass flow rates kg/hr (lb/hr). The span of this monitoring system shall be set so that the equivalent emission limit of sub. (3) (b) will be between 30% and 70% of the measurement range of the instrument system. NR 440.684(7)(b)2.2. Except as provided in subd. 3.: A monitoring device to measure the temperature of the gas leaving the combustion zone of the incinerator, if compliance with sub. (3) (a) is achieved through the use of an oxidation control system or a reduction control system followed by a continually operated incineration device. The monitoring device shall be certified by the manufacturer to be accurate to within ± 1% of the temperature being measured. When performance tests are conducted under the provision of s. NR 440.08 to demonstrate compliance with the standards under sub. (3), the temperature of the gas leaving the incinerator combustion zone shall be determined using the monitoring device. If the volumetric ratio of sulfur dioxide to sulfur dioxide plus total reduced sulfur (expressed as SO2) in the gas leaving the incinerator is ≥ 0.98, then temperature monitoring may be used to demonstrate that sulfur dioxide emission monitoring is sufficient to determine total sulfur emissions. At all times during the operation of the facility, the owner or operator shall maintain the average temperature of the gas leaving the combustion zone of the incinerator at or above the appropriate level determined during the most recent performance test to ensure the sulfur compound oxidation criteria are met. Operation at lower average temperatures may be considered by the department to be unacceptable operation and maintenance of the affected facility. The owner or operator may request that the minimum incinerator temperature be reestablished by conducting new performance tests under s. NR 440.08. NR 440.684(7)(b)3.3. The owner or operator may, as an alternative to subd. 2., install, calibrate, maintain, and operate a continuous emission monitoring system for total reduced sulfur compounds as required in par. (d) in addition to a sulfur dioxide emission monitoring system. The sum of the equivalent sulfur mass emission rates from the 2 monitoring systems shall be used to compute the total sulfur emission rate (E). NR 440.684(7)(c)(c) Where compliance is achieved through the use of a reduction control system not followed by a continually operated incineration device, the owner or operator shall install, calibrate, maintain, and operate a continuous monitoring system to measure the emission rate of reduced sulfur compounds as SO2 equivalent in the gases discharged to the atmosphere. The SO2 equivalent compound emission rate shall be expressed in terms of equivalent sulfur mass flow rates kg/hr (lb/hr). The span of this monitoring system shall be set so that the equivalent emission limit of sub. (3) (b) will be between 30 and 70% of the measurement range of the system. NR 440.684(7)(d)(d) For those sources required to comply with pars. (b) and (c), the average sulfur emission reduction efficiency achieved (R) shall be calculated for each 24-hour clock interval. The 24-hour interval may begin and end at any selected clock time but shall be consistent. The 24-hour average reduction efficiency (R) shall be computed based on the 24-hour average sulfur production rate (S) and sulfur emission rate (E) using the equation in sub. (5) (c) 1. NR 440.684(7)(d)1.1. Data obtained from the sulfur production rate monitoring device specified in par. (a) shall be used to determine S. NR 440.684(7)(d)2.2. Data obtained from the sulfur emission rate monitoring systems specified in par. (b) or (c) shall be used to calculate a 24-hour average for the sulfur emission rate (E). The monitoring system shall provide at least one data point in each successive 15-minute interval. At least 2 data points shall be used to calculate each 1-hour average. A minimum of 18 1-hour averages shall be used to compute each 24-hour average. NR 440.684 NR 440.684(7)(e)(e) In lieu of complying with par. (b) or (c), those sources with a design capacity of less than 152 Mg/d (150 long ton/day) of H2S expressed as sulfur may calculate the sulfur emission reduction efficiency achieved for each 24-hour period by using the following equation: where:
R is the sulfur dioxide removal efficiency achieved during the 24-hour period, percent
K2 is a conversion factor, 0.02400 Mg/d per kg/hr (0.01071 long ton/day per lb/hr)
S is the sulfur production rate during the 24-hour period, kg/hr (lb/hr)
X is the sulfur feed rate in the acid gas, Mg/d (long ton/day)
NR 440.684(7)(g)(g) The continuous emission monitoring systems required in sub. (7) (b) 1., (b) 3., and (c) shall be subject to the emission monitoring requirements of s. NR 440.13. For conducting the continuous emission monitoring system performance evaluation required by s. NR 440.13 (3), Performance Specification 2 of 40 CFR part 60, Appendix B, incorporated by reference in s. NR 440.17, shall apply, and Method 6 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17, shall be used for systems required by par. (b). NR 440.684(8)(a)(a) Records of the calculations and measurements required in subs. (3) (a) and (b) and (7) (a) to (g) shall be retained for at least 2 years following the date of the measurements by owners and operators subject to this section. This requirement is included under s. NR 440.07 (5). NR 440.684(8)(b)(b) Each owner or operator shall submit a written report of excess emissions to the department semiannually. For the purpose of these reports, excess emissions are defined as: NR 440.684(8)(b)1.1. Any 24-hour period (at consistent intervals) during which the average sulfur emission reduction efficiency (R) is less than the minimum required efficiency (Z). NR 440.684(8)(b)2.2. For any affected facility electing to comply with the provisions of sub. (7) (b) 2., any 24-hour period during which the average temperature of the gases leaving the combustion zone of an incinerator is less than the appropriate operating temperatures determined during the most recent performance test in accordance with the provisions of sub. (7) (b) 2. Each 24-hour period shall consist of at least 96 temperature measurements equally spaced over the 24 hours. NR 440.684(8)(c)(c) To certify that a facility is exempt from the control requirements of these standards, each owner or operator of a facility with a design capacity less than 2 LT/D of H2S in the acid gas (expressed as sulfur) shall keep, for the life of the facility, an analysis demonstrating that the facility’s design capacity is less than 2 LT/D of H2S expressed as sulfur. NR 440.684(8)(d)(d) Each owner or operator who elects to comply with sub. (7) (e) shall keep, for the life of the facility, a record demonstrating that the facility’s design capacity is less than 150 LT/D of H2S expressed as sulfur. NR 440.684(9)(9) Optional procedure for measuring hydrogen sulfide in acid gas-tutwiler procedure. NR 440.684(9)(a)(a) General. The Tutwiler procedure may be used to measure hydrogen sulfide in acid gas in accordance with the Gas Engineer’s Handbook, first edition, second printing, Fuel Gas Engineering Practices, page 6/25, incorporated by reference in s. NR 440.17. When an instantaneous sample is desired and H2S concentration is 10 grains per 1000 cubic foot or more, a 100 ml Tutwiler burette is used. For concentrations less than 10 grains, a 500 ml Tutwiler burette and more dilute solutions are used. In principle this method consists of titrating hydrogen sulfide in a gas sample directly with a standard solution of iodine. NR 440.684(9)(b)(b) Apparatus. (See Figure 1.) A 100 or 500 ml capacity Tutwiler burette with 2-way glass stopcock at the bottom and 3-way stopcock at the top is connected either with inlet tubulature or a glass-stoppered cylinder, 10 ml capacity, graduated in 0.1 ml subdivisions, with rubber tubing connecting the burette with a leveling bottle. NR 440.684(9)(c)1.1. Iodine stock solution, 0.1N. Weigh out 12.7 g of iodine and 20 to 25 g cp potassium iodide for each liter of solution. Dissolve the KI in as little water as necessary and then dissolve the iodine in the concentrated KI solution, make up to proper volume, and store in a glass-stoppered brown glass bottle. NR 440.684(9)(c)2.2. Standard iodine solution, 1 ml ± 0.001771 g I. Transfer 33.7 ml of the 0.1N stock solution into a 250 ml volumetric flask, add water to the mark and mix well. Then, for a 100 ml sample of gas, 1 ml of standard iodine solution is equivalent to 100 grains of H2S per cubic foot of gas. Starch solution. Rub into a thin paste about one teaspoonful of wheat starch with a little water, pour it into about a pint of boiling water and stir. After it has cooled, decant off the clear solution. Make fresh solution every few days.
NR 440.684(9)(d)(d) Procedure. Fill the leveling bulb with starch solution. Raise (L), open cock (G), open (F) to (A), and close (F) when the solution starts to run out of the gas inlet. Close (G). Purge the gas sampling line and connect it with (A). Lower (L) and open (F) and (G). When the liquid level is several ml past the 100 ml mark, close (G) and (F), and disconnect the sampling tube. Open (G) and bring the starch solution to the 100 ml mark by raising (L), then close (G). Open (F) momentarily, to bring the gas in the burette to atmospheric pressure, and close (F). Open (G) and bring the liquid level down to the 10 ml mark by lowering (L). Close (G), clamp the rubber tubing near (E) and disconnect it from the burette. Rinse the graduated cylinder with a standard iodine solution (0.00171 g I per ml), fill the cylinder and record the reading. Introduce successive small amounts of iodine thru (F), shaking well after each addition, and continue until a faint permanent blue color is obtained. Record the reading, subtract it from the previous reading and call the difference D. NR 440.684(9)(e)(e) Reagent test. With every fresh stock of starch solution, perform a blank test as follows: introduce fresh starch solution into the burette up to the 100 ml mark. Close (F) and (G). Lower (L) and open (G). When the liquid level reaches the 10 ml mark, close (G). With air in the burette titrate as during a test and up to the same end point. Call the ml of iodine used C. Then, NR 440.684(9)(f)(f) Sensitivity enhancement. Greater sensitivity can be attained if a 500 ml capacity Tutwiler burette is used with a more dilute (0.001N) iodine solution. Concentrations less than 1.0 grains per 100 cubic foot can be determined in this way. Usually the starch-iodine end point is much less distinct and a blank determination of end point, with H2S-free gas or air, is required.
Figure 1. Tutwiler burette (lettered items mentioned in text).
NR 440.684 HistoryHistory: Cr. Register, September, 1990, No. 417, eff. 10-1-90; am. (2) (a) 4., (4) (b), (7) (a) 2. and 4., (b) 3., (c), (d) (intro.), (e) and (8) (a), renum. (2) (b) 4. to 6. to be (2) (b) 5. to 7., cr. (2) (b) 4., r. and recr. (5), r. (6), Register, July, 1993, No. 451, eff. 8-1-93; am. (5) (c) 3., Register, December, 1995, No. 480, eff. 1-1-96; CR 06-109: am. (2) (a) 8. and (b) 1. to 3., (4) (b), (5) (b) 1. to 3., (c) 2. and 4. and (7) (b) 1. and (c), r. (2) (b) 4., renum. (2) (b) 5. to 7. to be (2) (b) 4. to 5. and am., r. and recr. (5) (c) 3. and (7) (e) Register May 2008 No. 629, eff. 6-1-08. NR 440.686NR 440.686 Volatile organic compound (VOC) emissions from synthetic organic chemical manufacturing industry (SOCMI) distillation operations. NR 440.686(1)(1) Applicability and designation of affected facility. NR 440.686(1)(a)(a) The provisions of this section apply to each affected facility designated in par. (b) that is part of a process unit that produces any of the chemicals listed in sub. (8) as a product, co-product, by-product or intermediate, except as provided in par. (c). NR 440.686(1)(b)(b) The affected facility is any of the following for which construction, modification or reconstruction commenced after December 30, 1983: NR 440.686(1)(b)1.1. Each distillation unit not discharging its vent stream into a recovery system. NR 440.686(1)(b)2.2. Each combination of a distillation unit and the common recovery system into which its vent stream is discharged. NR 440.686(1)(b)3.3. Each combination of 2 or more distillation units and the common recovery system into which their vent streams are discharged. NR 440.686(1)(c)1.1. Any distillation unit operating a part of a process unit which produces coal tar or beverage alcohols or which uses, contains and produces no VOC is not an affected facility. NR 440.686(1)(c)3.3. Any distillation unit that is designed and operates as a batch operation is not an affected facility. NR 440.686(1)(c)4.4. Each affected facility that has a total resource effectiveness (TRE) index value greater than 8.0 is exempt from all provisions of this section except for subs. (3), (5) (d), (e) and (f) and (6) (h) and (L). NR 440.686(1)(c)5.5. Each affected facility in a process unit with a total design capacity for all chemicals produced within that unit of less than one gigagram per year is exempt from all provisions of this section except for the recordkeeping and reporting requirements in sub. (6) (j), (L) 6. and (n). NR 440.686(1)(c)6.6. Each affected facility operated with a vent stream flow rate less than 0.008 scm/min is exempt from all provisions of this section except for the test method and procedure and the recordkeeping and reporting requirements in subs. (5) (g) and (6) (i), (L) 5. and (o). NR 440.686 NoteNote: The intent of these standards is to minimize the emissions of VOC through the application of best demonstrated technology (BDT). The numerical emission limits in these standards are expressed in terms of total organic compounds (TOC), measured as TOC less methane and ethane. This emission limit reflects the performance of BDT.
NR 440.686(1)(d)1.1. Owners or operators of process vents that are subject to this section may choose to comply with the provisions of 40 CFR part 65, subpart D, as in effect on December 14, 2000, to satisfy the requirements of subs. (3) to (6). The provisions of 40 CFR part 65, subpart D, as in effect on December 14, 2000, also satisfy the criteria of par. (c) 4. and 6. Other provisions applying to an owner or operator who chooses to comply with 40 CFR part 65, subpart D, as in effect on December 14, 2000, are provided in 40 CFR 65.1. NR 440.686(1)(d)2.2. Owners or operators who choose to comply with 40 CFR part 65, subpart D, as in effect on December 14, 2000, shall also comply with ss. NR 440.01, 440.02, 440.05, 440.06, 440.07 (1) (a) and (d), 440.14 and 440.15 for those process vents. All sections or subsections from ss. NR 440.01 to 440.19 not specified in this subdivision do not apply to owners or operators of process vents complying with 40 CFR part 65, subpart D, as in effect on December 14, 2000, except that provisions required to be met prior to implementing 40 CFR part 65 still apply. Owners or operators who choose to comply with 40 CFR part 65, subpart D, as in effect on December 14, 2000, shall comply with 40 CFR part 65, subpart A. NR 440.686(1)(d)3.3. Owners or operators who choose to comply with 40 CFR part 65, subpart D, as in effect on December 14, 2000, at initial startup shall comply with subds. 1. and 2. for each vent stream on and after the date on which the initial performance test is completed, but not later than 60 days after achieving the maximum production rate at which the affected facility will be operated, or 180 days after the initial startup, whichever date comes first. NR 440.686(1)(d)4.4. Each owner or operator subject to the provisions of this section that chooses to comply with 40 CFR part 65, subpart D, as in effect on December 14, 2000, at initial startup shall notify the administrator of the specific provisions of 40 CFR 65.63 (a) (1), (2) or (3), as in effect on December 14, 2000, with which the owner or operator has elected to comply. Notification shall be submitted with the notification of initial startup required by 40 CFR 65.5 (b). NR 440.686(2)(2) Definitions. As used in this section, all terms not defined here shall have the meaning given them in s. NR 440.02 and the following terms shall have the specific meanings given them: NR 440.686(2)(a)(a) “Batch distillation operation” means a noncontinuous distillation operation in which a discrete quantity or batch of liquid feed is charged into a distillation unit and distilled at one time. After the initial charging of the liquid feed, no additional liquid is added during the distillation operation. NR 440.686(2)(b)(b) “Boiler” means any enclosed combustion device that extracts useful energy in the form of steam. NR 440.686(2)(c)(c) “By compound” means by individual steam components, not carbon equivalents. NR 440.686(2)(d)(d) “Continuous recorder” means a data recording device recording an instantaneous data value at least once every 15 minutes. NR 440.686(2)(e)(e) “Distillation operation” means an operation separating one or more feed streams into 2 or more exit streams, each exit stream having component concentrations different from those in the feed streams. The separation is achieved by the redistribution of the components between the liquid and vapor- phase as they approach equilibrium within the distillation unit. NR 440.686(2)(f)(f) “Distillation unit” means a device or vessel in which distillation operations occur, including all associated internals, such as trays or packing, and accessories, such as reboiler, condenser, vacuum pump, steam jet or other similar device, plus any associated recovery system. NR 440.686(2)(g)(g) “Flame zone” means the portion of the combustion chamber in a boiler occupied by the flame envelope. NR 440.686(2)(h)(h) “Flow indicator” means a device which indicates whether gas flow is present in a vent stream. NR 440.686(2)(i)(i) “Halogenated vent stream” means any vent stream determined to have a total concentration (by volume) of compounds containing halogens of 20 ppmv (by compound) or greater. NR 440.686(2)(j)(j) “Incinerator” means any enclosed combustion device that is used for destroying organic compounds and does not extract energy in the form of steam or process heat. NR 440.686(2)(k)(k) “Process heater” means a device that transfers heat liberated by burning fuel to fluids contained in tubes, including all fluids except water that is heated to produce steam. NR 440.686(2)(L)(L) “Process unit” means equipment assembled and connected by pipes or ducts to produce, as intermediates or final products, one or more of the chemicals in sub. (8). A process unit can operate independently if supplied with sufficient fuel or raw materials and sufficient product storage facilities. NR 440.686(2)(m)(m) “Product” means any compound or chemical listed in sub. (8) that is produced for sale as a final product as that chemical or for use in the production of other chemicals or compounds. By-products, co-products and intermediates are considered to be products. NR 440.686(2)(n)(n) “Recovery device” means an individual unit of equipment, such as an absorber, carbon adsorber or condenser, capable of and used for the purpose of recovering chemicals for use, reuse or sale. NR 440.686(2)(o)(o) “Recovery system” means an individual recovery device or series of such devices applied to the same vent stream. NR 440.686(2)(p)(p) “Total organic compounds” or “TOC” means those compounds measured according to the procedures in sub. (5) (b) 4. For the purposes of measuring molar composition as required in sub. (5) (e) 2. a., hourly emissions rate as required in sub. (5) (e) 5. and (f), and TOC concentration as required in sub. (6) (b) 4. and (g) 4., those compounds which the department has determined do not contribute appreciably to the formation of ozone are to be excluded. The compounds to be excluded are identified in s. NR 400.02 (162). NR 440.686(2)(q)(q) “TRE index value” means a measure of supplemental total resource requirement per unit reduction of TOC associated with an individual distillation vent stream, based on vent stream flow rate, emission rate of TOC net heating, value and corrosion properties, whether or not the vent stream is halogenated, as quantified by the equation given under sub. (5) (e). NR 440.686(2)(r)(r) “Vent stream” means any gas stream discharged directly from a distillation facility to the atmosphere or indirectly to the atmosphere after diversion through other process equipment. The vent stream excludes relief valve discharges and equipment leaks including, but not limited to, pumps, compressors and valves. NR 440.686(3)(3) Standards. Each owner or operator of any affected facility shall comply with par. (a), (b) or (c) for each vent stream on and after the date on which the initial performance test required by s. NR 440.08 and sub. (5) is completed, but not later than 60 days after achieving the maximum production rate at which the affected facility will be operated or 180 days after the initial startup, whichever date comes first. Each owner or operator shall either: NR 440.686(3)(a)(a) Reduce emission of TOC, less methane and ethane, by 98 weight-percent or to a TOC, less methane and ethane, concentration of 20 ppmv, on a dry basis corrected to 3% oxygen, whichever is less stringent. If a boiler or process heater is used to comply with this paragraph, then the vent stream shall be introduced into the flame zone of the boiler or process heater; or NR 440.686(3)(c)(c) Maintain a TRE index value greater than 1.0 without use of VOC emission control devices.
