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The ISASMELT process is an energy-efficient smelting process that was jointly developed from the 1970s to the 1990s by Mount Isa Mines Limited (a subsidiary of MIM Holdings Limited and now part of Glencore Xstrata plc) and the Australian government’s Commonwealth Scientific and Industrial Research Organisation ("CSIRO"). It has relatively low capital and operating costs for a smelting process. ISASMELT technology has been applied to lead, copper, and nickel smelting, and by 2013 fifteen plants were in operation in ten countries, with another five in various stages of development.〔(List of Isasmelt installations )〕 The installed capacity of the operating plants in 2013 was over 8 million tonnes per year (t/y) of feed materials, with additional capacity to come on line in 2013 and 2014.〔Information provided courtesy of Xstrata Technology〕 Smelters based on the copper ISASMELT process are among the lowest-cost copper smelters in the world.〔J L Bill, T E Briffa, A S Burrows, C R Fountain, D Retallick, J M I Tuppurainen, J S Edwards, and P Partington, "Isasmelt—Mount Isa copper smelter progress update," in: ''Sulfide Smelting 2002'', Eds R L Stephens and H Y Sohn (The Minerals, Metals and Materials Society: Warrendale, Pennsylvania), 2002, 181–193.〕 ==The ISASMELT Furnace== An ISASMELT furnace is an upright-cylindrical shaped steel vessel that is lined with refractory bricks.〔Xstrata Technology, "ISASMELT – High productivity, clean smelting," ISASMELT brochure, 2012. Available from: (Isasmelt brochure ). Accessed 22 April 2013.〕 There is a molten bath of slag, matte or metal (depending on the application) at the bottom of the furnace. A steel lance is lowered into the bath through a hole in the roof of the furnace, and air or oxygen-enriched air that is injected through the lance into the bath causes vigorous agitation of the bath. Mineral concentrates or materials for recycling are dropped into the bath through another hole in the furnace roof or, in some cases, injected down the lance. These feed materials react with the oxygen in the injected gas, resulting in an intensive reaction in a small volume (relative to other smelting technologies). ISASMELT lances contain one or more devices called "swirlers" that cause the injected gas to spin within the lance, forcing it against the lance wall, cooling it. The cooling effect results in a layer of slag "freezing" on the outside of the lance. This layer of solid slag protects the lance from the high temperatures inside the furnace. The tip of the lance that is submerged in the bath eventually wears out, and the worn lance is easily replaced with a new one when necessary. The worn tips are subsequently cut off and a new tip welded onto the lance body before it is returned to the furnace. ISASMELT furnaces typically operate in the range of 1000–1200 °C, depending on the application.〔〔W J Errington, J H Fewings, V P Keran and W T Denholm, "The Isasmelt lead smelting process," ''Transactions of the Institution of Mining and Metallurgy (Section C: Mineral Processing and Extractive Metallurgy)'', 96, (1987), C1–C6.〕 The refractory bricks that form the internal lining of the furnace protect the steel shell from the heat inside the furnace. The products are removed from the furnace through one or more "tap holes" in a process called "tapping". This can be either continuous removal or in batches, with the tap holes being blocked with clay at the end of a tap, and then reopened by drilling or with a thermic lance when it is time for the next tap. The products are allowed to separate in a settling vessel, such as a rotary holding furnace or an electric furnace. While smelting sulfide concentrates, most of the energy needed to heat and melt the feed materials is derived from the reaction of oxygen with the sulfur and iron in the concentrate. However, a small amount of supplemental energy is required. ISASMELT furnaces can use a variety of fuels, including coal, coke, petroleum coke, oil and natural gas. The solid fuel can be added through the top of the furnace with the other feed materials, or it can be injected down the lance. Liquid and gaseous fuels are injected down the lance. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ISASMELT」の詳細全文を読む スポンサード リンク
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