Wis. Admin. Code Department of Natural Resources NR 463.12

Current through October 28, 2024

Section NR 463.12 - Definitions

For terms not defined in this section, the definitions contained in chs. NR 400 and 460 apply to the terms in this subchapter, with definitions in ch. NR 460 taking priority over definitions in ch. NR 400. If this section defines a term which is also defined in ch. NR 400 or 460, the definition in this section applies in this subchapter. In this subchapter:

(1) "Add-on air pollution control device" means equipment installed on a process vent that reduces the quantity of a pollutant that is emitted to the air.

(2) "Afterburner" means an air pollution control device that uses controlled flame combustion to convert combustible materials to noncombustible gases; also known as an incinerator or a thermal oxidizer.

(3) "Aluminum scrap" means fragments of aluminum stock removed during manufacturing, manufactured aluminum articles or parts rejected or discarded and useful only as material for reprocessing, and waste and discarded material made of aluminum.

(4) "Aluminum scrap shredder" means a unit that crushes, grinds or breaks aluminum scrap into a more uniform size prior to processing or charging to a scrap dryer, delacquering kiln, decoating kiln or furnace. A bale breaker is not an aluminum scrap shredder.

(5) "Bag leak detection system" means an instrument that is capable of monitoring particulate matter loadings in the exhaust of a baghouse in order to detect bag failures. A bag leak detection system may operate on triboelectric, light scattering, light transmittance or other effect to monitor relative particulate matter loadings.

(6) "Chips" means small, uniformly-sized, unpainted pieces of aluminum scrap, typically below 11/4 inches in any dimension, primarily generated by turning, milling, boring and machining of aluminum parts.

(7) "Clean charge" means furnace charge materials, including molten aluminum; T-bar; sow; ingot; billet; pig; alloying elements; aluminum scrap known by the owner or operator to be entirely free of paints, coatings and lubricants; uncoated and unpainted aluminum chips that have been thermally dried or treated by a centrifugal cleaner; aluminum scrap dried at 343 °C (650 °F) or higher; aluminum scrap delacquered and decoated at 482 °C (900 °F) or higher, and runaround scrap.

(8) "Cover flux" means salt added to the surface of molten aluminum in a group 1 or group 2 furnace, without agitation of the molten aluminum, for the purpose of preventing oxidation.

(9) "Customer returns" means any aluminum product which is returned by a customer to the aluminum company that originally manufactured the product prior to resale of the product or further distribution in commerce, and which contains no paint or other solid coatings.

(10) "Dioxins and furans" or "D&F" means tetra-, penta-, hexa- and octachlorinated dibenzo dioxins and furans.

(11) "Dross" means the slags and skimmings from aluminum melting and refining operations consisting of fluxing agents, impurities or oxidized and non-oxidized aluminum, from scrap aluminum charged into the furnace.

(12) "Dross-only furnace" means a furnace, typically of rotary barrel design, dedicated to the reclamation of aluminum from dross formed during melting, holding, fluxing or alloying operations carried out in other process units. Dross and salt flux are the sole feedstocks to this type of furnace.

(13) "Emission unit" means a group 1 furnace or in-line fluxer at a secondary aluminum production facility.

(14) "Fabric filter" means an add-on air pollution control device used to capture particulate matter by filtering gas streams through filter media; also known as a baghouse.

(15) "Feed or charge" means, for a furnace or other process unit that operates in batch mode, the total weight of material, including molten aluminum, T-bar, sow, ingot, other material and alloying agents that enter the furnace during an operating cycle. For a furnace or other process unit that operates continuously, feed or charge means the weight of material, including molten aluminum, T-bar, sow, ingot, other material and alloying agents that enter the process unit within a specified time period, such as a time period equal to the performance test period. The feed or charge for a dross-only furnace includes the total weight of dross and solid flux.

(16) "Fluxing" means refining of molten aluminum to improve product quality, achieve product specifications, or reduce material loss, including the addition of solvents to remove impurities and the injection of gases such as chlorine or chlorine mixtures to remove magnesium (demagging) or hydrogen bubbles (degassing). Fluxing may be performed in the furnace or outside the furnace by an in-line fluxer.

(17) "Furnace hearth" means the combustion zone of a furnace in which the molten metal is contained.

(18) "Group 1 furnace" means a furnace of any design that melts, holds or processes aluminum that contains paint, lubricants, coatings or other foreign materials with or without reactive fluxing or processes clean charge with reactive fluxing.

(19) "Group 2 furnace" means a furnace of any design that melts, holds or processes only clean charge and that performs no fluxing or performs fluxing using only nonreactive, non-HAP-containing, non-HAP-generating gases or agents.

(20) "HCl" means, for the purposes of this subchapter, emissions of hydrogen chloride that serve as a surrogate measure of the total emissions of the HAPs hydrogen chloride, hydrogen fluoride and chlorine.

(21) "In-line fluxer" means a device exterior to a furnace, located in a transfer line from a furnace, used in fluxing molten aluminum; also known as a flux box, degassing box or demagging box.

(22) "Internal scrap" means all aluminum scrap regardless of the level of contamination which originates from castings or extrusions produced by an aluminum die casting facility, aluminum foundry or aluminum extrusion facility, and which remains at all times within the control of the company that produced the castings or extrusions.

(23) "Lime" means calcium oxide or other alkaline reagent.

(24) "Lime-injection" means the continuous addition of lime upstream of a fabric filter.

(25) "Melting and holding furnace" means a group 1 furnace that processes only clean charge, performs melting, holding, and fluxing functions, and does not transfer molten aluminum to or from another furnace except for the purposes of alloy changes, off-specification product drains or maintenance activities.

(26) "Operating cycle" means for a batch process, the period beginning when the feed material is first charged to the operation and ending when all feed material charged to the operation has been processed. For a batch melting and holding furnace process, operating cycle means the period including the charging and melting of scrap aluminum and the fluxing, refining, alloying and tapping of molten aluminum.

(27) "PM" means, for the purposes of this subchapter, emissions of particulate matter that serve as a measure of total particulate emissions and as a surrogate for metal HAPs contained in the particulates, including antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, nickel and selenium.

(28) "Pollution prevention" means source reduction as defined under the Pollution Prevention Act of 1990 (42 USC 13101 to 13109) including equipment or technology modifications, process or procedure modifications, reformulation or redesign of products, substitution of raw materials, and improvements in housekeeping, maintenance, training, or inventory control, and other practices that reduce or eliminate the creation of pollutants through increased efficiency in the use of raw materials, energy, water or other resources or protection of natural resources by conservation.

(29) "Reactive fluxing" means the use of any gas, liquid, or solid flux, other than cover flux, that results in a HAP emission. Argon and nitrogen are not reactive and do not produce HAPs.

(30) "Reconstruction" means the replacement of components of an affected source or emission unit such that the fixed capital cost of the new components exceeds 50% of the fixed capital cost that would be required to construct a comparable new affected source, and it is technologically and economically feasible for the reconstructed source to meet relevant standards established in this subchapter. Replacement of the refractory in a furnace is routine maintenance and is not a reconstruction. The repair and replacement of in-line fluxer components, such as rotors, shafts, burner tubes, refractory or warped steel, is considered to be routine maintenance and is not considered a reconstruction. In-line fluxers are typically removed to a maintenance or repair area and are replaced with repaired units. The replacement of an existing in-line fluxer with a repaired unit is not considered a reconstruction.

(31) "Residence time" means, for an afterburner, the duration of time required for gases to pass through the afterburner combustion zone. Residence time is calculated by dividing the afterburner combustion zone volume in cubic feet by the volumetric flow rate of the gas stream in actual cubic feet per second.

(32) "Rotary dross cooler" means a water-cooled rotary barrel device that accelerates cooling of dross.

(33) "Runaround scrap" means scrap materials generated on-site by aluminum casting, extruding, rolling, scalping, forging, forming, stamping, cutting and trimming operations and that do not contain paint or solid coatings. Uncoated and unpainted aluminum chips generated by turning, boring, milling and similar machining operations may be clean charge if they have been thermally dried or treated by a centrifugal cleaner, but are not considered to be runaround scrap.

(34) "Scrap dryer, delacquering kiln or decoating kiln" means a unit used primarily to remove various organic contaminants such as oil, paint, lacquer, ink, plastic or rubber from aluminum scrap, including used beverage containers, prior to melting.

(35) "Secondary aluminum processing unit" or "SAPU" means one of the following:

(a) An existing SAPU means all existing group 1 furnaces and all existing in-line fluxers within a secondary aluminum production facility. Each existing group 1 furnace or existing in-line fluxer is considered an emission unit within a secondary aluminum processing unit.

(b) A new SAPU means any combination of individual group 1 furnaces and in-line fluxers within a secondary aluminum processing facility which either were constructed or reconstructed after February 11, 1999, or have been permanently redesignated as new emission units pursuant to s. NR 463.13(11). Each of the group 1 furnaces or in-line fluxers within a new SAPU is considered an emission unit within that secondary aluminum processing unit.

(36) "Secondary aluminum production facility" means any establishment using clean charge, aluminum scrap or dross from aluminum production as the raw material and performing one or more of the following processes: scrap shredding, scrap drying, delacquering or decoating, thermal chip drying, recovery of aluminum from dross, in-line fluxing, dross cooling or furnace operations such as melting, holding, sweating, refining, fluxing or alloying. A secondary aluminum production facility may be independent or part of a primary aluminum production facility. For purposes of this subchapter, aluminum die casting facilities, aluminum foundries and aluminum extrusion facilities are not considered to be secondary aluminum production facilities if the only materials they melt are clean charge, customer returns or internal scrap, and if they do not operate sweat furnaces, thermal chip dryers, scrap dryers, delacquering kilns or decoating kilns. The determination of whether a facility is a secondary aluminum production facility is only for purposes of this subchapter and any regulatory requirements which are derived from the applicability of this subchapter, and is separate from any determination which may be made under other environmental laws and regulations, including whether the same facility is a "secondary metal production facility" as that term is used in 42 USC 7479(1) or a "secondary metal production plant" as that term is used in s. NR 405.02(22) (a) 1.

(37) "Sidewell" means an open well adjacent to the hearth of a furnace with connecting arches between the hearth and the open well through which molten aluminum is circulated between the hearth, where heat is applied by burners, and the open well, which is used for charging scrap and solid flux or salt to the furnace, injecting fluxing agents and skimming dross.

(38) "Sweat furnace" means a furnace used exclusively to reclaim aluminum from scrap that contains substantial quantities of iron by using heat to separate the low-melting point aluminum from the scrap while the higher melting-point iron remains in solid form.

(39) "TEQ" means the international method of expressing toxicity equivalents for dioxins and furans as defined in Interim Procedures for Estimating Risks Associated with Exposures to Mixtures of Chlorinated Dibenzo-p-Dioxins and -Dibenzofurans (CDDs and CDFs) and 1989 Update (EPA-625/3-89-016), incorporated by reference in s. NR 484.05(12).

(40) "THC" means total hydrocarbon emissions that also serve as a surrogate for the emissions of organic HAP compounds.

(41) "Thermal chip dryer" means a device that uses heat to evaporate oil or oil and water mixtures from unpainted or uncoated aluminum chips. Pre-heating boxes or other dryers which are used solely to remove water from aluminum scrap are not considered to be thermal chip dryers.

(42) "Three-day, 24-hour rolling average" means daily calculations of the average 24-hour emission rate in lb/ton of feed or charge over the 3 most recent consecutive 24-hour periods, for a secondary aluminum processing unit.

(43) "Total reactive chlorine flux injection rate" means the sum of the total weight of chlorine in the gaseous or liquid reactive flux and the total weight of chlorine in the solid reactive chloride flux, divided by the total weight of feed or charge, as determined by the procedure in s. NR 463.163(16)

Wis. Admin. Code Department of Natural Resources NR 463.12

CR 04-023: cr. Register December 2008 No. 636, eff. 1-1-09.