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)(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.