Wisconsin Administrative Code
Department of Natural Resources
NR 400-499 - Environmental Protection - Air Pollution Control
Chapter NR 440 - Standards of performance for new stationary sources
Subchapter II - Standards of Performance
Section NR 440.43 - Ferroalloy production facilities

(a) The provisions of this section are applicable to the following affected facilities: electric submerged arc furnaces which produce silicon metal, ferrosilicon, calcium silicon, silicomanganese zirconium, ferrochrome silicon, silvery iron, high-carbon ferrochrome, charge chrome, standard ferromanganese, silicomanganese, ferromanganese silicon or calcium carbide; and dust-handling equipment.

(b) Any facility under par. (a) that commences construction or modification after October 21, 1974, is subject to the requirements of this section.

(a) "Blowing tap" means any tap in which an evolution of gas forces or projects jets of flame or metal sparks beyond the ladle, runner or collection hood.

(b) "Calcium carbide" means material containing 70 to 85% calcium carbide by weight.

(c) "Calcium silicon" means that alloy as defined by ASTM A495-94, incorporated by reference in s. NR 440.17(2) (a) 6.

(d) "Capture system" means the equipment (including hoods, ducts, fans, dampers, etc.) used to capture or transport particulate matter generated by an affected electric submerged arc furnace to the control device.

(e) "Charge chrome" means that alloy containing 52 to 70% by weight chromium, 5 to 8% by weight carbon, and 3 to 6% by weight silicon.

(f) "Control device" means the air pollution control equipment used to remove particulate matter generated by an electric submerged arc furnace from an effluent gas stream.

(g) "Dust-handling equipment" means any equipment used to handle particulate matter collected by the air pollution control device (and located at or near such device) serving any electric submerged arc furnace subject to this section.

(h) "Electric submerged arc furnace" means any furnace wherein electrical energy is converted to heat energy by transmission of current between electrodes partially submerged in the furnace charge.

(i) "Ferrochrome silicon" means that alloy as defined by ASTM A482-93, incorporated by reference in s. NR 440.17(2) (a) 4.

(j) "Ferromanganese silicon" means that alloy containing 63 to 66% by weight manganese, 28 to 32% by weight silicon, and a maximum of 0.08% by weight carbon.

(k) "Ferrosilicon" means that alloy as defined by ASTM A100-93, incorporated by reference in s. NR 440.17(2) (a) 2., grades A, B, C, D and E which contains 50 or more percent by weight silicon.

(L) "Furnace charge" means any material introduced into the electric submerged arc furnace, and may consist of, but is not limited to, ores, slag, carbonaceous material and limestone.

(m) "Furnace cycle" means the time period from completion of a furnace product tap to the completion of the next consecutive product tap.

(n) "Furnace power input" means the resistive electrical power consumption of an electric submerged arc furnace as measured in kilowatts.

(o) "High-carbon ferrochrome" means that alloy as defined by ASTM A101-93, incorporated by reference in s. NR 440.17(2) (a) 3., grades HC1 through HC6.

(p) "Product change" means any change in the composition of the furnace charge that would cause the electric submerged arc furnace to become subject to a different mass standard applicable under this section.

(q) "Silicomanganese" means that alloy as defined by ASTM A483-74 (reapproved 1988), incorporated by reference in s. NR 440.17(2) (a) 5.

(r) "Silicomanganese zirconium" means that alloy containing 60 to 65% by weight silicon, 1.5 to 2.5% by weight calcium, 5 to 7% by weight zirconium, 0.75 to 1.25% by weight aluminum, 5 to 7% by weight manganese, and 2 to 3% by weight barium.

(s) "Silicon metal" means any silicon alloy containing more than 96% silicon by weight.

(t) "Silvery iron" means any ferrosilicon, as defined by ASTM A100-93 incorporated by reference in s. NR 440.17(2) (a) 2., which contains less than 30% silicon.

(u) "Slag" means the more or less completely fused and vitrified matter separated during the reduction of a metal from its ore.

(v) "Standard ferromanganese" means that alloy as defined by ASTM A99-82 (reapproved 1987), incorporated by reference in s. NR 440.17(2) (a) 1.

(w) "Tapping" means the removal of slag or product from the electric submerged arc furnace under normal operating conditions such as removal of metal under normal pressure and movement by gravity down the spout into the ladle.

(x) "Tapping period" means the time duration from initiation of the process of opening the tap hole until plugging of the tap hole is complete.

(y) "Tapping station" means that general area where molten product or slag is removed from the electric submerged arc furnace.

(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 from any electric submerged arc furnace any gases which:

(b) 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 from any dust-handling equipment any gases which exhibit 10% opacity or greater.

(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 from any electric submerged arc furnace any gases which contain, on a dry basis, 20 or greater volume % of carbon monoxide. Combustion of such gases under conditions acceptable to the department constitutes compliance with this subsection. Acceptable conditions include, but are not limited to, flaring of gases or use of gases as fuel for other processes.

(a) The owner or operator subject to the provisions of this section shall install, calibrate, maintain and operate a continuous monitoring system for measurement of the opacity of emissions discharged into the atmosphere from control devices.

(b) For the purpose of reports required under s. NR 440.07(3), the owner or operator shall report as excess emissions all 6-minute periods in which the average opacity is 15% or greater.

(c) The owner or operator subject to the provisions of this section shall submit a written report of any product change to the department. Reports of product changes shall be postmarked not later than 30 days after implementation of the product change.

(a) The owner or operator of any electric submerged arc furnace subject to the provisions of this section shall maintain daily records of the following information:

(b) The owner or operator subject to the provisions of this section shall install, calibrate, maintain and operate a device to measure and continuously record the furnace power input. The furnace power input may be measured at the output or input side of the transformer. The device must have an accuracy of "5% over its operating range.

(c) The owner or operator subject to the provisions of this section shall install, calibrate and maintain a monitoring device that continuously measures and records the volumetric flow rate through each separately ducted hood of the capture system, except as provided under par. (e). The owner or operator of an electric submerged arc furnace that is equipped with a water cooled cover which is designed to contain and prevent escape of the generated gas and particulate matter shall monitor only the volumetric flow rate through the capture system for control of emissions from the tapping station. The owner or operator may install monitoring devices in any appropriate location in the exhaust duct such that reproducible flow rate monitoring will result. The flow rate monitoring device shall have an accuracy of "10% over its normal operating range and shall be calibrated according to the manufacturer's instructions. The department may require the owner or operator to demonstrate the accuracy of the monitoring device relative to Methods 1 and 2 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17.

(d) When performance tests are conducted under the provisions of s. NR 440.08 to demonstrate compliance with the standards under sub. (3) (a) 4. and 5., the volumetric flow rate through each separately ducted hood of the capture system shall be determined using the monitoring device required under par. (c). The volumetric flow rates shall be determined for furnace power input levels at 50 and 100% of the nominal rated capacity of the electric submerged arc furnace. At all times the electric submerged arc furnace is operated, the owner or operator shall maintain the volumetric flow rate at or above the appropriate levels for that furnace power input level determined during the most recent performance test. If emissions due to tapping are captured and ducted separately from emissions of the electric submerged arc furnace, during each tapping period the owner or operator shall maintain the exhaust flow rates through the capture system over the tapping station at or above the levels established during the most recent performance test. Operation at lower flow rates may be considered by the department to be unacceptable operation and maintenance of the affected facility. The owner or operator may request that these flow rates be reestablished by conducting new performance tests under s. NR 440.08.

(e) The owner or operator may as an alternative to par. (c) determine the volumetric flow rate through each fan of the capture system from the fan power consumption, pressure drop across the fan and the fan performance curve. Only data specific to the operation of the affected electric submerged arc furnace shall be acceptable for demonstration of compliance with the requirements of this paragraph. The owner or operator shall maintain on file a permanent record of the fan performance curve (prepared for a specific temperature) and shall:

(f) The volumetric flow rate through each fan of the capture system shall be determined from the fan power consumption, fan pressure drop, and fan performance curve specified under par. (e), during any performance test required under s. NR 440.08 to demonstrate compliance with the standards under sub. (3) (a) 4. and 5. The owner or operator shall determine the volumetric flow rate at a representative temperature for furnace power input levels of 50 and 100% of the nominal rated capacity of the electric submerged arc furnace. At all times the electric submerged arc furnace is operated, the owner or operator shall maintain the fan power consumption and fan pressure drop at levels such that the volumetric flow rate is at or above the levels established during the most recent performance test for that furnace power input level. If emissions due to tapping are captured and ducted separately from emissions of the electric submerged arc furnace, during each tapping period the owner or operator shall maintain the fan power consumption and fan pressure drop at levels such that the volumetric flow rate is at or above the levels established during the most recent performance test. Operation at lower flow rates may be considered by the department to be unacceptable operation and maintenance of the affected facility. The owner or operator may request that these flow rates be reestablished by conducting new performance tests under s. NR 440.08. The department may require the owner or operator to verify the fan performance curve by monitoring necessary fan operating parameters and determining the gas volume moved relative to Methods 1 and 2 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17.

(g) All monitoring devices required under pars. (c) and (e) shall be checked for calibration annually in accordance with the procedures under s. NR 440.13(2).

(a) During any performance test required in s. NR 440.08, the owner or operator may not allow gaseous diluents to be added to the effluent gas stream after the fabric in an open pressurized fabric filter collector unless the total gas volume flow from the collector is accurately determined and considered in the determination of emissions.

(b) 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).

(c) The owner or operator shall determine compliance with the particulate matter standards in sub. (3) as follows:

(d) During the particulate matter run, the maximum open hood area, in hoods with segmented or otherwise moveable sides, under which the process is expected to be operated and remain in compliance with all standards shall be recorded. Any future operation of the hooding system with open areas in excess of the maximum is not permitted.

(e) To comply with sub. (6) (d) or (f), the owner or operator shall use the monitoring devices in sub. (6) (c) or (e) to make the required measurements as determined during the performance test.