NR 440.682(5)(a)(a) If, in the administrator's judgement, an alternative means of emission limitation will achieve a reduction in VOC emissions at least equivalent to the reduction in VOC emissions achieved under any design, equipment, work practice or operational standard, the administrator will publish, in the federal register, a notice permitting the use of that alternative means for the purpose of compliance with that standard. The notice may condition permission on requirements related to the operation and maintenance of the alternative means.
NR 440.682(5)(b)
(b) Any notice under
par. (a) shall be published only after notice and an opportunity for a public hearing.
NR 440.682(5)(c)
(c) The administrator will consider applications under this subsection from either owners or operators of affected facilities, or manufacturers of control equipment.
NR 440.682(5)(d)
(d) The administrator will treat applications under this subsection according to the following criteria, except in cases where he or she concludes that other criteria are appropriate:
NR 440.682(5)(d)1.
1. The applicant shall collect, verify and submit test data, covering a period of at least 12 months, necessary to support the finding in
par. (a).
NR 440.682(5)(d)2.
2. If the applicant is an owner or operator of an affected facility, he or she shall commit in writing to operate and maintain the alternative means so as to achieve a reduction in VOC emissions at least equivalent to the reduction in VOC emissions achieved under the design, equipment, work practice or operational standard.
NR 440.682(6)(a)(a) Each owner or operator subject to the provisions of this section shall comply with the requirements of
pars. (b) and
(c) in addition to the requirements of
s. NR 440.62 (7).
NR 440.682(6)(b)
(b) The following recordkeeping requirements shall apply to pressure relief devices subject to the requirements of
sub. (4) (b) 1.:
NR 440.682(6)(b)1.
1. When each leak is detected as specified in
sub. (4) (b) 2., a weatherproof and readily visible identification, marked with the equipment identification number, shall be attached to the leaking equipment. The identification on the pressure relief device may be removed after it has been repaired.
NR 440.682(6)(b)2.
2. When each leak is detected as specified in
sub. (4) (b) 2., the following information shall be recorded in a log and shall be kept for 2 years in a readily accessible location:
NR 440.682(6)(b)2.a.
a. The instrument and operator identification numbers and the equipment identification number.
NR 440.682(6)(b)2.b.
b. The date the leak was detected and the dates of each attempt to repair the leak.
NR 440.682(6)(b)2.d.
d. “Above 10,000 ppm" if the maximum instrument reading measured by the methods specified in after each repair attempt is 10,000 ppm or greater.
NR 440.682(6)(b)2.e.
e. “Repair delayed" and the reason for the delay if a leak is not repaired within 15 calendar days after discovery of the leak.
NR 440.682(6)(b)2.f.
f. The signature of the owner or operator (or designate) whose decision it was that repair could not be effected without a process shutdown.
NR 440.682(6)(b)2.g.
g. The expected date of successful repair of the leak if a leak is not repaired within 15 days.
NR 440.682(6)(b)2.h.
h. Dates of process unit shutdowns that occur while the equipment is unrepaired.
NR 440.682(6)(c)
(c) An owner or operator shall comply with the following requirement in addition to the requirement of
s. NR 440.62 (10): Information and data used to demonstrate that a reciprocating compressor is in wet gas service to apply for the exemption in
sub. (4) (f) shall be recorded in a log that is kept in a readily accessible location.
NR 440.682(7)(a)(a) Each owner or operator subject to the provisions of this section shall comply with the requirements of
pars. (b) and
(c) in addition to the requirements of
s. NR 440.62 (8).
NR 440.682(7)(b)
(b) An owner or operator shall include the following information in the initial semiannual report in addition to the information required in
s. NR 440.62 (8) (b) 1. to
4.: number of pressure relief devices subject to the requirements of
sub. (4) (b) except for those pressure relief devices designated for no detectable emission under the provision of
s. NR 440.62 (3) (d) 1. and those pressure relief devices complying with
s. NR 440.62 (3) (d) 3.
NR 440.682 History
History: Cr.
Register, September, 1990, No. 417, eff. 10-1-90; am. (4) (b) 3. a.,
Register, July, 1993, No. 451, eff. 8-1-93
; correction in (4) (b) and (d) made under s. 13.93 (2m) (b) 7.,
Register, November, 1999, No. 527;
CR 06-109: am. (3) (f) and (4) (h) 1. and 2. Register May 2008 No. 629, eff. 6-1-08. NR 440.684
NR 440.684 Onshore natural gas processing: SO2 emissions. NR 440.684(1)(1)
Applicability and designation of affected facilities. NR 440.684(1)(a)(a) The provisions of this section are applicable to the following affected facilities that process natural gas: each sweetening unit, and each sweetening unit followed by a sulfur recovery unit.
NR 440.684(1)(b)
(b) Facilities that have a design capacity less than 2 long tons per day (LT/D) of hydrogen sulfide (H
2S) in the acid gas (expressed as sulfur) are required to comply with
sub. (8) (c) but are not required to comply with
subs. (3) to
(7).
NR 440.684(1)(c)
(c) The provisions of this section are applicable to facilities located on land and include facilities located onshore which process natural gas produced from either onshore or offshore wells.
NR 440.684(1)(d)
(d) The provisions of this section apply to each affected facility identified in
par. (a) which commences construction or modification after January 20, 1984.
NR 440.684(1)(e)
(e) The provisions of this section do not apply to sweetening facilities producing acid gas that is completely reinjected into oil-or-gas-bearing geologic strata or that is otherwise not released to the atmosphere.
NR 440.684(2)(a)1.
1. “Acid gas" means a gas stream of hydrogen sulfide (H
2S) and carbon dioxide (CO
2) that has been separated from sour natural gas by a sweetening unit.
NR 440.684(2)(a)2.
2. “Natural gas" means a naturally occurring mixture of a hydrocarbon and nonhydrocarbon gases found in geologic formations beneath the earth's surface. The principal hydrocarbon constituent is methane.
NR 440.684(2)(a)3.
3. “Onshore" means all facilities except those that are located in the territorial seas or on the outercontinental shelf.
NR 440.684(2)(a)4.
4. “Reduced sulfur compounds" means hydrogen sulfide (H
2S), carbonyl sulfide (COS), and carbon disulfide (CS
2).
NR 440.684(2)(a)5.
5. “Sulfur production rate" means the rate of liquid sulfur accumulation from the sulfur recovery unit.
NR 440.684(2)(a)6.
6. “Sulfur recovery unit" means a process device that recovers element sulfur from acid gas.
NR 440.684(2)(a)7.
7. “Sweetening unit" means a process device that separates the H
2S and CO
2 contents from the sour natural gas stream.
NR 440.684(2)(a)8.
8. “Total SO
2 equivalents" means the sum of volumetric or mass concentrations of the sulfur compounds obtained by adding the quantity existing as SO
2 to the quantity of SO
2 that would be obtained if all reduced sulfur compounds were converted to SO
2, ppmv or kg/dscm (lb/dscf).
NR 440.684(2)(b)
(b) As used in this section, all symbols not defined in this subsection have the meanings given them in
s. NR 440.03.
NR 440.684(2)(b)1.
1. “E" is the sulfur emission rate expressed as elemental sulfur in kg/hr (lb/hr), rounded to one decimal place.
NR 440.684(2)(b)2.
2. “R" is the sulfur emission reduction efficiency achieved in percent carried to one decimal place.
NR 440.684(2)(b)3.
3. “S" is the sulfur production rate in kg/hr (lb/hr), rounded to one decimal place.
NR 440.684(2)(b)4.
4. “X" is the sulfur feed rate from the sweetening unit, that is, the H
2S in the acid gas, expressed as sulfur, Mg/d (long ton/day), rounded to one decimal place.
NR 440.684(2)(b)5.
5. “Y" is the sulfur content of the acid gas from the sweetening unit, expressed as mole percent H
2S (dry basis) rounded to one decimal place.
NR 440.684(2)(b)6.
6. “Z" is the minimum required sulfur dioxide (SO
2) emission reduction efficiency, expressed as percent carried to one decimal place. Z
i refers to the reduction efficiency required at the initial performance test. Z
c refers to the reduction efficiency required on a continual basis after compliance with Z
i has been demonstrated.
NR 440.684(3)(a)(a) During the initial performance test required by
s. NR 440.08 (2), each owner or operator shall achieve, at a minimum, an SO
2 emission reduction efficiency (Z
i) to be determined from Table 1 based on the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility.
NR 440.684(3)(b)
(b) After demonstrating compliance with the provisions of
par. (a), the owner or operator shall achieve, at a minimum, an SO
2 emission reduction efficiency (Z
c) to be determined from Table 2 based on the sulfur feed rate (X) and the sulfur content of the acid gas (Y) of the affected facility.
NR 440.684(4)(a)1.1. To determine compliance with the standards for sulfur dioxide specified in
sub. (3) (a), during the initial performance test as required by
s. NR 440.08, the minimum required sulfur dioxide emissions reduction efficiency (Z) is compared to the emission reduction efficiency (R) achieved by the sulfur recovery technology.
NR 440.684(4)(a)1.a.
a. If R is greater than or equal to Z
i, the affected facility is in compliance.
NR 440.684(4)(a)2.
2. Following the initial determination of compliance as required by
s. NR 440.08, any subsequent compliance determinations that may be required by the department shall compare R to Z
c.
NR 440.684(5)(a)(a) In conducting the performance tests required in
s. NR 440.08, the owner or operator shall use as reference methods and procedures the test methods in Appendix A of
40 CFR part 60, incorporated by reference in
s. NR 440.17, or other methods and procedures as specified in this subsection, except as provided in
s. NR 440.08 (2).
NR 440.684(5)(b)
(b) During a performance test required by
s. NR 440.08, the owner or operator shall determine the minimum required reduction efficiencies (Z) of SO
2 emissions as required in
sub. (3) (a) and
(b) as follows:
where:
X is the average sulfur feed rate, Mg/d (long ton/day)
Qa is the average volumetric flow rate of acid gas from sweetening unit, dscm/day (dscf/day)
Y is the average H2S concentration in acid gas feed from sweetening unit, percent by volume, expressed as a decimal
K is (32kg S/kg-mole)/((24.04 dscm/kg-mole)(1000kg S/Mg)) = 1.331 x 10-3 Mg/dscm for metric units, and is (32 lb S/lb-mole)/((385.36 dscf/lb-mole)(2240 lb S/long ton)) = 3.707 x 10-5 long ton/dscf for English units
NR 440.684(5)(b)2.
2. The continuous readings from the process flowmeter shall be used to determine the average volumetric flow rate (Q
a) in dscm/day (dscf/day) of the acid gas from the sweetening unit for each run.
NR 440.684(5)(b)3.
3. The Tutwiler procedure in
sub. (9) or a chromatographic procedure following ASTM E260-96, incorporated by reference in
s. NR 440.17 (2) (a) 75., shall be used to determine the H
2S concentration in the acid gas feed from the sweetening unit. At least one sample per hour, at equally spaced intervals, shall be taken during each 4-hour run. The arithmetic mean of all samples shall be the average H
2S concentration (Y) on a dry basis for the run. By multiplying the result from the Tutwiler procedure by 1.62
10
-3, the units gr/100 scf are converted to volume percent.
NR 440.684(5)(b)4.
4. Using the information from
par. (b) 1. and
3., Tables 1 and 2 shall be used to determine the required initial (Z
i) and continuous (Z
c) reduction efficiencies of SO
2 emissions.
NR 440.684(5)(c)1.
1. The emission reduction efficiency (R) achieved by the sulfur recovery technology shall be computed for each run using the following equation: -
See PDF for diagram 
NR 440.684(5)(c)2.
2. The level indicators or manual soundings shall be used to measure the liquid sulfur accumulation rate in the product storage tanks. Readings taken at the beginning and end of each run, the tank geometry, sulfur density at the storage temperature and sample duration shall be used to determine the sulfur production rate (S) in kg/hr (lb/hr) for each run.
NR 440.684(5)(c)3.
3. The emission rate of sulfur shall be computed for each run as follows:
where:
E is the emission rate of sulfur per run, kg/hr (lb/hr)
Ce is the concentration of sulfur equivalent (SO
2 + reduced sulfur), g/dscm (lb/dscf)
Qsd is the volumetric flow rate of effluent gas, dscm/hr (dscf/hr)
K1 is a conversion factor, 1000 g/kg (7000 gr/lb)
NR 440.684(5)(c)4.
4. The concentration (C
e) of sulfur equivalent shall be the sum of the SO
2 and TRS concentrations, after being converted to sulfur equivalents. For each run and each of the test methods specified in this paragraph, the sampling time shall be at least 4 hours. Method 1 shall be used to select the sampling site. The sampling point in the duct shall be at the centroid of the cross- section if the area is less than 5 m
2 (54 ft
2) or at a point no closer to the walls than 1 m (39 in.) if the cross-sectional area is 5 m
2 (54 ft
2) or more and the centroid is more than 1 m (39 in.) from the wall.
NR 440.684(5)(c)4.a.
a. Method 6 shall be used to determine the SO
2 concentration. Eight samples of 20 minutes each shall be taken at 30-minute intervals. The arithmetic average shall be the concentration for the run. The concentration shall be multiplied by 0.5
10
-3 to convert the results to sulfur equivalent.
NR 440.684(5)(c)4.b.
b. Method 15 shall be used to determine the TRS concentration from reduction-type devices or where the oxygen content of the effluent gas is less than 1.0% by volume. The sampling rate shall be at least 3 liters/min (0.1 ft
3/min) to insure minimum residence time in the sample line. Sixteen samples shall be taken at 15-minute intervals. The arithmetic average of all the samples shall be the concentration for the run. The concentration in ppm reduced sulfur as sulfur shall be multiplied by 1.333
10
-3 to convert the results to sulfur equivalent.
NR 440.684(5)(c)4.c.
c. Method 16A or 15 shall be used to determine the reduced sulfur concentration from oxidation-type devices or where the oxygen content of the effluent gas is greater than 1.0% by volume. Eight samples of 20 minutes each shall be taken at 30-minute intervals. The arithmetic average shall be the concentration for the run. The concentration in ppm reduced sulfur as sulfur shall be multiplied by 1.333
10
-3 to convert the results to sulfur equivalent.
