Current through August 26, 2024
(1) APPLICABILITY
AND DESIGNATION OF AFFECTED FACILITY.
(a) The
affected facilities in primary aluminum reduction plants to which this section
applies are potroom groups and anode bake plants.
(b) Except as provided in par. (c), any
affected facility under par. (a) that commences construction or modification
after October 23, 1974, is subject to the requirements of this section.
(c) An owner or operator of an
affected facility under par. (a) may elect to comply with the requirements of
this section or the requirements of 40 CFR part 63 .
(2) DEFINITIONS. As used in this section,
terms not defined in this subsection have the meanings given in s.
NR 440.02.
(a)
"Aluminum equivalent" means an amount of aluminum which can be produced from a
Mg of anodes produced by an anode bake plant as determined by sub. (6) (b) 4.
b.
(b) "Anode bake plant" means a
facility which produces carbon anodes for use in a primary aluminum reduction
plant.
(c) "Potroom" means a
building unit which houses a group of electrolytic cells in which aluminum is
produced.
(d) "Potroom group" means
an uncontrolled potroom, a potroom which is controlled individually, or a group
of potrooms or potroom segments ducted to a common control system.
(e) "Primary aluminum reduction plant" means
any facility manufacturing aluminum by electrolytic reduction.
(f) "Primary control system" means an air
pollution control system designed to remove gaseous and particulate fluorides
from exhaust gases which are captured at the cell.
(g) "Roof monitor" means that portion of the
roof of a potroom where gases not captured at the cell exit from the
potroom.
(h) "Total fluorides"
means elemental fluorine and all fluoride compounds as measured by reference
methods specified in sub. (6) or by equivalent or alternative
methods.
(3) STANDARDS
FOR FLUORIDES.
(a) On and after the date on
which the initial performance test required to be conducted by s.
NR 440.08 is
completed, no owner or operator subject to the provisions of this section may
cause to be discharged into the atmosphere from any affected facility any gases
containing total fluorides, as measured according to sub. (6), in excess of:
1. 1.0 kg/Mg (2.0 lb/ton) of aluminum
produced for potroom groups at Soderberg plants, except that emissions betwee n
1.0 kg/Mg and 1.3 kg/Mg (2.6 lb/ton) shall be considered in compliance if the
owner or operator demonstrates that exemplary operation and maintenance
procedures were used with respect to the emission control system and that
proper control equipment was operating at the affected facility during the
performance tests;
2. 0.95 kg/Mg
(1.9 lb/ton) of aluminum produced for potroom groups at prebake plants, except
that emissions betwee n 0.95 kg/Mg and 1.25 kg/Mg (2.5 lb/ton) shall be
considered in compliance if the owner or operator demonstrates that exemplary
operation and maintenance procedures were used with respect to the emission
control system and that proper control equipment was operating at the affected
facility during the performance test; and
3. 0.050 kg/Mg (0.10 lb/ton) of aluminum
equivalent for anode bake plants.
(b) Within 30 days of any performance test
which reveals emissions which fall between the 1.0 kg/Mg and 1.3 kg/Mg levels
in par. (a) 1. or between to 0.95 kg/Mg and 1.25 kg/Mg levels in par. (a) 2.,
the owner or operator shall submit a report to the department indicating
whether all necessary control devices were on-line and operating properly
during the performance test, describing the operating and maintenance
procedures followed, and setting forth any explanation for the excess
emissions.
(4) STANDARD
FOR VISIBLE EMISSIONS.
(a) On and after the
date on which the performance test required to be conducted by s.
NR 440.08 is
completed, no owner or operator subject to the provisions of this section may
cause to be discharged into the atmosphere:
1. From any potroom group any gases which
exhibit 10% opacity or greater, or
2. From any anode bake plant any gases which
exhibit 20% opacity or greater.
(5) MONITORING OF OPERATIONS.
(a) The owner or operator of any affected
facility subject to the provisions of this section shall install, calibrate,
maintain and operate monitoring devices which can be used to determine daily
the weight of aluminum and anode produced. The weighing devices shall have an
accuracy of " 5% over their operating range.
(b) The owner or operator of any affected
facility shall maintain a record of daily production rates of aluminum and
anodes, raw material feed rates, and cell or potline voltages.
(c) Following the initial performance test as
required under s.
NR 440.08(1), an owner or operator shall
conduct a performance test at least once each month during the life of the
affected facility, except when malfunctions prevent representative sampling, as
provided under s.
NR 440.08(3). The owner or operator
shall give the department at least 15 days advance notice of each test. The
department may require additional testing under ch. NR 439.
Note: Under
40 CFR
60.195(b), an owner or
operator may petition the administrator to establish an alternate testing
requirement that requires testing less frequently than once each month for a
primary control system or an anode bake plant if it can be shown that their
emissions have low variability during day-to-day operations. The alternative
testing requirement must be published in the federal register and include a
testing schedule and, in the case of a primary control system, the method to be
used to determine primary control system emissions for the purpose of
performance tests.
(6) TEST METHODS AND PROCEDURES.
(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).
(b) The owner or operator shall determine
compliance with the total fluorides and visible emission standards in subs. (3)
and (4) as follows:
1. The emission rate (Ep)
of total fluorides from potroom groups shall be computed for each run using the
following equation:
Ep = [(Cs Qsd)1 + (Cs Qsd)2]/(PK)
where:
Ep is the emission rate of total fluorides from a potroom
group, kg/Mg (lb/ton)
Cs is the concentration of total fluorides, mg/dscm
(gr/dscf)
Qsd is the volumetric flow rate of effluent gas, dscm/hr
(dscf/hr)
P is the aluminum production rate, Mg/hr (ton/hr)
K is the conversion factor, 106 mg/kg (7000 gr/lb)
1 is the subscript for primary control system effluent gas
2 is the subscript for secondary control system or roof
monitor effluent gas
2.
The emission rate (Eb) of total fluorides from anode bake plants shall be
computed for each run using the following equation:
Eb = (Cs Qsd)/(P eK)
where:
Eb is the emission rate of total fluorides, kg/Mg (lb/ton)
of aluminum equivalent
Cs is the concentration of total fluorides, mg/dscm
(gr/dscf)
Qsd is the volumetric flow rate of effluent gas, dscm/hr
(dscf/hr)
Pe is the aluminum equivalent for anode production rate,
Mg/hr (ton/hr)
K is the conversion factor, 106 mg/kg (7000 gr/lb)
3. Method 13A or 13B shall be used
for ducts or stacks and Method 14 for roof monitors not employing stacks or
pollutant collection systems, to determine the total fluorides concentration
(Cs) and volumetric flow rate (Qsd) of the effluent gas. The sampling time and
sample volume for each run shall be at least 8 hours and 6.80 dscm (240 dscf)
for potroom groups and at least 4 hours and 3.40 dscm (120 dscf) for anode bake
plants.
4. The monitoring devices
of sub. (5) (a) shall be used to determine the daily weight of aluminum and
anode produced.
a. The aluminum production
rate (P) shall be determined by dividing 720 hours into the weight of aluminum
tapped from the affected facility during a period of 30 days before and
including the final run of a performance test.
b. The aluminum equivalent production rate
(Pe) for anodes shall be determined as 2 times the average weight of anode
produced during a representative oven cycle divided by the cycle time. An owner
or operator may establish a multiplication factor other than 2 by submitting
production records of the amount of aluminum produced and the concurrent weight
of anodes consumed by the potrooms.
5. Method 9 and the procedures in s.
NR 440.11 shall be used to determine opacity.
