NR 460.10(2)(a)(a) Owners or operators using flares to comply with the provisions of
40 CFR part 63 or
chs. NR 460 to
469 shall monitor these control devices to assure that they are operated and maintained in conformance with their designs. Applicable subparts of
40 CFR part 63 or applicable parts of
chs. NR 460 to
469 will provide provisions stating how owners or operators using flares shall monitor these control devices.
NR 460.10(2)(b)
(b) Flares shall be steam-assisted, air-assisted or non-assisted.
NR 460.10(2)(c)
(c) Flares shall be operated at all times when emissions may be vented to them.
NR 460.10(2)(d)
(d) Flares shall be designed for and operated with no visible emissions, except for periods not to exceed a total of 5 minutes during any 2 consecutive hours. Method 22 in Appendix A of
40 CFR part 60, incorporated by reference in
s. NR 484.04 (13), shall be used to determine the compliance of flares with the visible emission provisions of
40 CFR part 63 or
chs. NR 460 to
469. The observation period is 2 hours and shall be used according to Method 22.
NR 460.10(2)(e)
(e) Flares shall be operated with a flame present at all times. The presence of a flare pilot flame shall be monitored using a thermocouple or any other equivalent device to detect the presence of a flame.
NR 460.10(2)(f)
(f) An owner or operator has the choice of adhering to the heat content specifications in
subd. 2., and the maximum tip velocity specifications in
par. (g) or
(h), or adhering to the requirements in
subd. 1.
NR 460.10(2)(f)1.a.a. Flares shall be used that have a diameter of 3 inches or greater, are nonassisted, have a hydrogen content of 8.0% (by volume) or greater, and are designed for and operated with an exit velocity less than 37.2 m/sec (122 ft/sec) and less than the velocity V
max, as determined by the following equation:
Vmax = (XH2 - K1) * K2
where:
Vmax is the maximum permitted velocity, m/sec
K1 is the constant, 6.0 volume-percent hydrogen
K2 is the constant, 3.9 (m/sec)/volume-percent hydrogen
X
H2 is the volume-percent of hydrogen, on a wet basis, as calculated by using ASTM D1946-90, incorporated by reference in
s. NR 484.10 (28)
NR 460.10(2)(f)2.
2. Flares shall be used only with the net heating value of the gas being combusted at 11.2 MJ/scm (300 Btu/scf) or greater if the flare is steam-assisted or air-assisted; or with the net heating value of the gas being combusted at 7.45 MJ/scm (200 Btu/scf) or greater if the flares is non-assisted. The net heating value of the gas being combusted in a flare shall be calculated using the following equation:
where:
HT is the 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 one mole is 20°C
K is a constant
where the standard temperature for (g-mole/scm) is 20°C
C
i is the concentration of sample component i in ppmv on a wet basis, as measured for organics by Test Method 18 and measured for hydrogen and carbon monoxide by ASTM D1946-90, incorporated by reference in
s. NR 484.10 (28)
H
i is the net heat of combustion of sample component i, kcal/g-mole at 25
°C and 760 mm Hg. The heat of combustion may be determined using ASTM D4809-00, incorporated by reference in
s. NR 484.10 (55), if published values are not available or cannot be calculated
n is the number of sample components
NR 460.10(2)(g)1.1. Steam-assisted and nonassisted flares shall be designed for and operated with an exit velocity less than 18.3 m/sec (60 ft/sec), except as provided in
subds. 2. and
3. The actual exit velocity of a flare shall be determined by dividing the volumetric flow rate of gas being combusted, in units of emission standard temperature and pressure, as determined by Method 2, 2A, 2C, or 2D in Appendix A of
40 CFR part 60, incorporated by reference in
s. NR 484.04 (13), as appropriate, by the unobstructed (free) cross-sectional area of the flare tip.
NR 460.10(2)(g)2.
2. Steam-assisted and nonassisted flares designed for and operated with an exit velocity, as determined by the method specified in
subd. 1., equal to or greater than 18.3 m/sec (60 ft/sec) but less than 122 m/sec (400 ft/sec), are allowed if the net heating value of the gas being combusted is greater than 37.3 MJ/scm (1,000 Btu/scf).
NR 460.10(2)(g)3.
3. Steam-assisted and nonassisted flares designed for and operated with an exit velocity, as determined by the method specified in
subd. 1., less than the velocity V
max, as determined by the method specified in this subdivision, but less than 122 m/sec (400 ft/sec) are allowed. The maximum permitted velocity, V
max, for flares complying with this subdivision shall be determined by the following equation: -
See PDF for diagram 
where:
Vmax is the maximum permitted velocity, m/sec
28.8 is a constant
31.7 is a constant
HT is the net heating value as determined in par. (f)
NR 460.10(2)(h)
(h) Air-assisted flares shall be designed and operated with an exit velocity less than the velocity V
max. The maximum permitted velocity, V
max, for air-assisted flares shall be determined by the following equation: -
See PDF for diagram
where:
Vmax is the maximum permitted velocity, m/sec
8.71 is a constant
0.708 is a constant
HT is the net heating value as determined in par. (f)
NR 460.10 History
History: Cr.
Register, March, 1997, No. 495, eff. 4-1-97; am. (2) (f),
Register, November, 1999, No. 527, eff. 12-1-99;
CR 00-175: r. and recr. (2) (f), am. (2) (h)
Register March 2002 No. 555, eff. 4-1-02; corrections in (2) (d) and (g) 1. made under s. 13.93 (2m) (b) 7., Stats.,
Register March 2002 No. 555.
NR 460.11
NR 460.11
Performance track provisions. NR 460.11(1)
(1) Notwithstanding any other requirements in
40 CFR part 63 or
chs. NR 460 to
469, an affected source at any major source or any area source at a performance track member facility, as defined in
s. NR 460.02 (37g), which is subject to regular periodic reporting under any relevant standard, may submit periodic reports at an interval that is twice the length of the regular period specified in the applicable standards provided, that for sources subject to permits under
ch. NR 406 or
407, no interval for any report of the results of any required monitoring may be less frequent than once in every 6 months.
NR 460.11(2)
(2) Notwithstanding any other requirements in
40 CFR part 63 or
chs. NR 460 to
469, the modifications of reporting requirements in
sub. (3) apply to any major source at a performance track member facility, as defined in
s. NR 460.02 (37g), which is subject to requirements under any relevant standard and which has done all of the following:
NR 460.11(2)(a)
(a) Reduced its total HAP emissions to less than 25 tons per year.
NR 460.11(2)(b)
(b) Reduced its emissions of each individual HAP to less than 10 tons per year.
NR 460.11(2)(c)
(c) Reduced emissions of all HAPs covered by each MACT standard to at least the level required for full compliance with the applicable emission standard.
NR 460.11(3)
(3) For affected sources at any area source at a performance track member facility, as defined in
s. NR 460.02 (37g), that meet the requirements of
sub. (2) (c), or for affected sources at any major source that meet the requirements of
sub. (2):
NR 460.11(3)(a)
(a) If the emission standard to which the affected source is subject is based on add-on control technology, and the affected source complies by using add-on control technology, all required reporting elements in the periodic report may be met through an annual certification that the affected source is meeting the emission standard by continuing to use that control technology. The affected source shall continue to meet all relevant monitoring and recordkeeping requirements. The compliance certification shall meet the requirements delineated in Clean Air Act section 114 (a) (3).
NR 460.11(3)(b)
(b) If the emission standard to which the affected source is subject is based on add-on control technology, and the affected source complies by using pollution prevention, all required reporting elements in the periodic report may be met through an annual certification that the affected source is continuing to use pollution prevention to reduce HAP emissions to levels at or below those required by the applicable emission standard. The affected source shall maintain records of all calculations that demonstrate the level of HAP emissions required by the emission standard as well as the level of HAP emissions achieved by the affected source. The affected source shall continue to meet all relevant monitoring and recordkeeping requirements. The compliance certification shall meet the requirements delineated in Clean Air Act section 114 (a) (3).
NR 460.11(3)(c)
(c) If the emission standard to which the affected source is subject is based on pollution prevention, and the affected source complies by using pollution prevention and reduces emissions by an additional 50% or greater than required by the applicable emission standard, all required reporting elements in the periodic report may be met through an annual certification that the affected source is continuing to use pollution prevention to reduce HAP emissions by an additional 50% or greater than required by the applicable emission standard. The affected source shall maintain records of all calculations that demonstrate the level of HAP emissions required by the emission standard as well as the level of HAP emissions achieved by the affected source. The affected source shall continue to meet all relevant monitoring and recordkeeping requirements. The compliance certification shall meet the requirements delineated in Clean Air Act section 114 (a) (3).
NR 460.11(3)(d)
(d) Notwithstanding the provisions of
pars. (a) to
(c), for sources subject to permits under
ch. NR 406 or
407, the results of any required monitoring and recordkeeping shall be reported not less frequently than once in every 6 months.
NR 460.11 History
History: CR 05-039: cr.
Register February 2006 No. 602, eff. 3-1-06.
