Chapter NR 661

NR 661.1031(37) (37) “Thin-film evaporation operation” means a distillation operation that employs a heating surface consisting of a large diameter tube that may be either straight or tapered, horizontal or vertical. Liquid is spread on the tube wall by a rotating assembly of blades that maintain a close clearance from the wall or actually ride on the film of liquid on the wall.

NR 661.1031(38) (38) “Vapor 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 661.1031(39) (39) “Vented” means discharged through an opening, typically an open-ended pipe or stack, allowing the passage of a stream of liquids, gases, or fumes into the atmosphere. The passage of liquids, gases, or fumes is caused by mechanical means such as compressors or vacuum-producing systems or by process-related means such as evaporation produced by heating and not caused by tank loading and unloading, working losses, or by natural means such as diurnal temperature changes.

NR 661.1031 History History: CR 19-082: cr. Register August 2020 No. 776, eff. 9-1-20.

NR 661.1032 NR 661.1032 Standards: process vents.

NR 661.1032(1) (1) A remanufacturer or other person that stores or treats hazardous secondary material in hazardous secondary material management units with process vents associated with distillation, fractionation, thin-film evaporation, solvent extraction, or air or steam stripping operations managing hazardous secondary material with organic concentrations of at least 10 ppmw shall do one of the following:

NR 661.1032(1)(a) (a) Reduce total organic emissions from all affected process vents at the facility below 1.4 kg/h (3 lb/h) and 2.8 Mg/yr (3.1 tons/yr).

NR 661.1032(1)(b) (b) Reduce, by use of a control device, total organic emissions from all affected process vents at the facility by 95 weight percent.

NR 661.1032(2) (2) If a remanufacturer or other person that stores or treats hazardous secondary material installs a closed-vent system and control device to comply with the provisions of sub. (1) the closed-vent system and control device shall meet the requirements specified in s. NR 661.1033.

NR 661.1032(3) (3) Determinations of vent emissions and emission reductions or total organic compound concentrations achieved by add-on control devices may be based on engineering calculations or performance tests. If performance tests are used to determine vent emissions, emission reductions, or total organic compound concentrations achieved by add-on control devices, the performance tests shall conform with the requirements specified in s. NR 661.1034 (3).

NR 661.1032(4) (4) When a remanufacturer or other person that stores or treats hazardous secondary material and the department do not agree on determinations of vent emissions or emission reductions or total organic compound concentrations achieved by add-on control devices based on engineering calculations, the procedures specified in s. NR 661.1034 (3) shall be used to resolve the disagreement.

NR 661.1032 History History: CR 19-082: cr. Register August 2020 No. 776, eff. 9-1-20.

NR 661.1033 NR 661.1033 Standards: closed-vent systems and control devices.

NR 661.1033(1) (1) A remanufacturer or other person that stores or treats hazardous secondary material in hazardous secondary material management units using closed-vent systems and control devices used to comply with provisions of this part shall comply with the provisions of this section.

NR 661.1033(2) (2) A control device involving vapor recovery, such as a condenser or adsorber, shall be designed and operated to recover the organic vapors vented to it with an efficiency of 95 weight percent or greater unless the total organic emission limits specified in s. NR 661.1032 (1) (a) for all affected process vents can be attained at an efficiency less than 95 weight percent.

NR 661.1033(3) (3) An enclosed combustion device, such as a vapor incinerator, boiler, or process heater, shall be designed and operated to reduce the organic emissions vented to it by 95 weight percent or greater; to achieve a total organic compound concentration of 20 ppmv, expressed as the sum of the actual compounds, not carbon equivalents, on a dry basis corrected to 3 percent oxygen; or to provide a minimum residence time of 0.50 seconds at a minimum temperature of 760°C. If a boiler or process heater is used as the control device, the vent stream shall be introduced into the flame zone of the boiler or process heater.

NR 661.1033(4) (4) 

NR 661.1033(4)(a) (a) A flare shall be designed for and operated with no visible emissions as determined by the methods specified in sub. (5) (a), except for periods not to exceed a total of 5 minutes during any 2 consecutive hours.

NR 661.1033(4)(b) (b) A flare shall be operated with a flame present at all times, as determined by the methods specified in sub. (6) (b) 3.

NR 661.1033(4)(c) (c) A flare shall be used only if the net heating value of the gas being combusted is 11.2 MJ/scm or greater if the flare is steam-assisted or air-assisted; or if the net heating value of the gas being combusted is 7.45 MJ/scm or greater if the flare is non-assisted. The net heating value of the gas being combusted shall be determined by the methods specified in sub. (5) (b).

NR 661.1033 Note Note: 1 megajoule/meter3 [MJ/m3] = 26.8391919932 Btu (IT)/foot3 [Btu/ft3].

NR 661.1033(4)(d) (d)

NR 661.1033(4)(d)1. 1. Except as provided in subs. (4) (d) 2. and 3., a steam-assisted or nonassisted flare shall be designed for and operated with an exit velocity, as determined by the methods specified in sub. (5) (c), less than 18.3 m/s.

NR 661.1033(4)(d)2. 2. A steam-assisted or nonassisted flare designed for and operated with an exit velocity, as determined by the methods specified in sub. (5) (c), equal to or greater than 18.3 m/s but less than 122 m/s is allowed if the net heating value of the gas being combusted is greater than 37.3 MJ/scm.

NR 661.1033(4)(d)3. 3. A steam-assisted or nonassisted flare designed for and operated with an exit velocity, as determined by the methods specified in sub. (5) (c), less than the velocity, Vmax, as determined by the method specified in sub. (5) (d) and less than 122 m/s is allowed.

NR 661.1033(4)(e) (e) An air-assisted flare shall be designed and operated with an exit velocity less than the velocity, Vmax, as determined by the method specified in sub. (5) (e).

NR 661.1033(4)(f) (f) A flare used to comply with this section shall be steam-assisted, air-assisted, or nonassisted.

NR 661.1033(5) (5) 

NR 661.1033(5)(a) (a) Reference Method 22 in 40 CFR part 60, incorporated by reference in s. NR 660.11, shall be used to determine the compliance of a flare with the visible emission provisions of this subchapter. The observation period is 2 hours and shall be used according to Method 22.

NR 661.1033(5)(b) (b) The net heating value of the gas being combusted in a flare shall be calculated using the following equation:

Where:

HT = Net heating value of the sample, MJ/scm; where the net enthalpy per mole of offgas is based on combustion at 25°C and 760 mm Hg, but the standard temperature for determining the volume corresponding to 1 mol is 20°C.

K = Constant, 1.74 x 10-7 (1/ppm) (g mol/scm) (MJ/kcal) where standard temperature for (g mol/scm) is 20°C.

Ci = Concentration of sample component i in ppm on a wet basis, as measured for organics by Reference Method 18 in chapter 60 and measured for hydrogen and carbon monoxide by ASTM D 1946-82, incorporated by reference in s. NR 660.11.

Hi = Net heat of combustion of sample component i, kcal/9 mol at 25°C and 760 mm Hg. The heats of combustion may be determined using ASTM D 2382-83, incorporated by reference in s. NR 660.11, if published values are not available or cannot be calculated.

NR 661.1033(5)(c) (c) The actual exit velocity of a flare shall be determined by dividing the volumetric flow rate, in units of standard temperature and pressure, as determined by Reference Methods 2, 2A, 2C or 2D in appendix A of 40 CFR part 60, incorporated by reference in s. NR 660.11, as appropriate, by the unobstructed, free, cross-sectional area of the flare tip.

NR 661.1033(5)(d) (d) The maximum allowed velocity in m/s, Vmax, for a flare complying with sub. (4) (d) 3. shall be determined by the following equation:

Where:

28.8 = Constant

31.7 = Constant

HT = The net heating value as determined in par. (b).

NR 661.1033(5)(e) (e) The maximum allowed velocity in m/s, Vmax, for an air-assisted flare shall be determined by the following equation:

Where:

8.706 = Constant

0.7084 = Constant

HT = The net heating value as determined in par. (b).

NR 661.1033(6) (6) A remanufacturer or other person that stores or treats hazardous secondary material shall monitor and inspect each control device required to comply with this section to ensure proper operation and maintenance of the control device by implementing all of the following requirements:

NR 661.1033(6)(a) (a) Install, calibrate, maintain, and operate according to the manufacturer’s specifications a flow indicator that provides a record of vent stream flow from each affected process vent to the control device at least once every hour. The flow indicator sensor shall be installed in the vent stream at the nearest feasible point to the control device inlet but before the point at which the vent streams are combined.

NR 661.1033(6)(b) (b) Install, calibrate, maintain, and operate according to the manufacturer’s specifications a device to continuously monitor control device operation as specified below:

NR 661.1033(6)(b)1. 1. For a thermal vapor incinerator, a temperature monitoring device equipped with a continuous recorder. The device shall have an accuracy of ±1 percent of the temperature being monitored in °C or ±0.5 °C, whichever is greater. The temperature sensor shall be installed at a location in the combustion chamber downstream of the combustion zone.

NR 661.1033(6)(b)2. 2. For a catalytic vapor incinerator, a temperature monitoring device equipped with a continuous recorder. The device shall be capable of monitoring temperature at 2 locations and have an accuracy of ±1 percent of the temperature being monitored in °C or ±0.5 °C, whichever is greater. One temperature sensor shall be installed in the vent stream at the nearest feasible point to the catalyst bed inlet and a second temperature sensor shall be installed in the vent stream at the nearest feasible point to the catalyst bed outlet.

NR 661.1033(6)(b)3. 3. For a flare, a heat sensing monitoring device equipped with a continuous recorder that indicates the continuous ignition of the pilot flame.

NR 661.1033(6)(b)4. 4. For a boiler or process heater having a design heat input capacity less than 44 MW, a temperature monitoring device equipped with a continuous recorder. The device shall have an accuracy of ±1 percent of the temperature being monitored in °C or ±0.5 °C, whichever is greater. The temperature sensor shall be installed at a location in the furnace downstream of the combustion zone.

NR 661.1033(6)(b)5. 5. For a boiler or process heater having a design heat input capacity greater than or equal to 44 MW, a monitoring device equipped with a continuous recorder to measure a parameter that indicates good combustion operating practices are being used.

NR 661.1033(6)(b)6. 6. For a condenser, one of the following:

NR 661.1033(6)(b)6.a. a. A monitoring device equipped with a continuous recorder to measure the concentration level of the organic compounds in the exhaust vent stream from the condenser.

NR 661.1033(6)(b)6.b. b. A temperature monitoring device equipped with a continuous recorder. The device shall be capable of monitoring temperature with an accuracy of ±1 percent of the temperature being monitored in °C or ±0.5 °C, whichever is greater. The temperature sensor shall be installed at a location in the exhaust vent stream from the condenser exit or product side.

NR 661.1033(6)(b)7. 7. For a carbon adsorption system that regenerates the carbon bed directly in the control device such as a fixed-bed carbon adsorber, one of the following:

NR 661.1033(6)(b)7.a. a. A monitoring device equipped with a continuous recorder to measure the concentration level of the organic compounds in the exhaust vent stream from the carbon bed.

NR 661.1033(6)(b)7.b. b. A monitoring device equipped with a continuous recorder to measure a parameter that indicates the carbon bed is regenerated on a regular, predetermined time cycle.

NR 661.1033(6)(c) (c) Inspect the readings from each monitoring device required under pars. (a) and (b) at least once each operating day to check control device operation and, if necessary, immediately implement the corrective measures necessary to ensure the control device operates in compliance with the requirements of this section.

NR 661.1033(7) (7) A remanufacturer or other person that stores or treats hazardous secondary material in a hazardous secondary material management unit using a carbon adsorption system such as a fixed-bed carbon adsorber that regenerates the carbon bed directly on-site in the control device shall replace the existing carbon in the control device with fresh carbon at a regular, predetermined time interval that is no longer than the carbon service life established as a requirement under s. NR 661.1035 (2) (d) 3. f.

NR 661.1033(8) (8) A remanufacturer or other person that stores or treats hazardous secondary material in a hazardous secondary material management unit using a carbon adsorption system such as a carbon canister that does not regenerate the carbon bed directly on-site in the control device shall replace the existing carbon in the control device with fresh carbon on a regular basis by using one of the following procedures:

NR 661.1033(8)(a) (a) Monitor the concentration level of the organic compounds in the exhaust vent stream from the carbon adsorption system on a regular schedule and replace the existing carbon with fresh carbon immediately when carbon breakthrough is indicated. The monitoring frequency shall be daily or at an interval no greater than 20% of the time required to consume the total carbon working capacity established as a requirement under s. NR 661.1035 (2) (d) 3. g., whichever is longer.

NR 661.1033(8)(b) (b) Replace the existing carbon with fresh carbon at a regular, predetermined time interval that is less than the design carbon replacement interval established as a requirement under s. NR 661.1035 (2) (d) 3. g.

NR 661.1033(9) (9) An alternative operational or process parameter may be monitored if it can be demonstrated that another parameter will ensure that the control device is operated in conformance with these standards and the control device’s design specifications.

NR 661.1033(10) (10) A remanufacturer or other person that stores or treats hazardous secondary material at an affected facility seeking to comply with the provisions of this chapter by using a control device other than a thermal vapor incinerator, catalytic vapor incinerator, flare, boiler, process heater, condenser, or carbon adsorption system is required to develop documentation including sufficient information to describe the control device operation and identify the process parameter or parameters that indicate proper operation and maintenance of the control device.

NR 661.1033(11) (11) A closed-vent system shall meet one of the following design requirements:

NR 661.1033(11)(a) (a) A closed-vent system shall be designed to operate with no detectable emissions, as indicated by an instrument reading of less than 500 ppmv above background as determined by the procedure specified in s. NR 661.1034 (2), and by visual inspections.

NR 661.1033(11)(b) (b) A closed-vent system shall be designed to operate at a pressure below atmospheric pressure. The system shall be equipped with at least one pressure gauge or other pressure measurement device that can be read from a readily accessible location to verify that negative pressure is being maintained in the closed-vent system when the control device is operating.

NR 661.1033(12) (12) A remanufacturer or other person that stores or treats hazardous secondary material shall monitor and inspect each closed-vent system required to comply with this section to ensure proper operation and maintenance of the closed-vent system by implementing all of the following requirements:

NR 661.1033(12)(a) (a) Each closed-vent system that is used to comply with sub. (11) (a) shall be inspected and monitored in accordance with all of the following requirements:

NR 661.1033(12)(a)1. 1. An initial leak detection monitoring of the closed-vent system shall be conducted by the remanufacturer or other person that stores or treats the hazardous secondary material on or before the date that the system becomes subject to this section. The remanufacturer or other person that stores or treats the hazardous secondary material shall monitor the closed-vent system components and connections using the procedures specified in s. NR 661.1034 (2) to demonstrate that the closed-vent system operates with no detectable emissions, as indicated by an instrument reading of less than 500 ppmv above background.

NR 661.1033(12)(a)2. 2. After initial leak detection monitoring required in subd. 1., the remanufacturer or other person that stores or treats the hazardous secondary material shall inspect and monitor the closed-vent system as follows:

NR 661.1033(12)(a)2.a. a. Closed-vent system joints, seams, or other connections that are permanently or semi-permanently sealed, such as a welded joint between 2 sections of hard piping or a bolted and gasketed ducting flange, shall be visually inspected at least once per year to check for defects that could result in air pollutant emissions. The remanufacturer or other person that stores or treats the hazardous secondary material shall monitor a component or connection using the procedures specified in s. NR 661.1034 (2) to demonstrate that it operates with no detectable emissions following any time the component is repaired or replaced, such as when a section of damaged hard piping is replaced with new hard piping, or the connection is unsealed, such as an unbolted flange.

NR 661.1033(12)(a)2.b. b. Closed-vent system components or connections other than those specified in subd. 2. a. shall be monitored annually and at other times as requested by the department, except as provided for under sub. (15), using the procedures specified in s. NR 661.1034 (2) to demonstrate that the components or connections operate with no detectable emissions.

NR 661.1033(12)(a)3. 3. In the event that a defect or leak is detected, the remanufacturer or other person that stores or treats the hazardous secondary material shall repair the defect or leak in accordance with the requirements under par. (c).

NR 661.1033(12)(a)4. 4. The remanufacturer or other person that stores or treats the hazardous secondary material shall maintain a record of the inspection and monitoring in accordance with the requirements specified in s. NR 661.1035.

NR 661.1033(12)(b) (b) Each closed-vent system that is used to comply with sub. (11) (b) shall be inspected and monitored in accordance with all of the following requirements:

NR 661.1033(12)(b)1. 1. The closed-vent system shall be visually inspected by the remanufacturer or other person that stores or treats the hazardous secondary material to check for defects that could result in air pollutant emissions. Defects include visible cracks, holes, or gaps in ductwork or piping or loose connections.

NR 661.1033(12)(b)2. 2. The remanufacturer or other person that stores or treats the hazardous secondary material shall perform an initial inspection of the closed-vent system on or before the date that the system becomes subject to this section. Thereafter, the remanufacturer or other person that stores or treats the hazardous secondary material shall perform the inspections at least once every year.

NR 661.1033(12)(b)3. 3. In the event that a defect or leak is detected, the remanufacturer or other person that stores or treats the hazardous secondary material shall repair the defect in accordance with the requirements under par. (c).

NR 661.1033(12)(b)4. 4. The remanufacturer or other person that stores or treats the hazardous secondary material shall maintain a record of the inspection and monitoring in accordance with the requirements specified in s. NR 661.1035.

NR 661.1033(12)(c) (c) The remanufacturer or other person that stores or treats the hazardous secondary material shall repair all detected defects according to all of the following:

NR 661.1033(12)(c)1. 1. Detectable emissions, as indicated by visual inspection, or by an instrument reading greater than 500 ppmv above background, shall be controlled as soon as practicable, but not later than 15 calendar days after the emission is detected, except as specified in subd. 3.

NR 661.1033(12)(c)2. 2. A first attempt at repair shall be made no later than 5 calendar days after the emission is detected.