Ural Mining and Metallurgical Company, Verkhnyaya Pyshma, Sverdlovsk Oblast, Russia

A. M. Panshin, Technical Officer

“Chelyabinsk Zinc Plant” JSC, Chelyabinsk, Russia
P. A. Kozlov, Head of Engineering Center, e-mail: pak@zinс.ru
D. A. Ivakin, Head of Technological Bureau of Engineering Center

There are given the results of investigation of thermal conditions of rotating furnace (60,0×4,0 m) during the processing of charge, which contains zinc cake and oxidized zinc-containing raw materials (middlings of non-ferrous and ferrous metallurgy). The calculation of heat balance shows that usage of coke fines, supplied into the Waelz kiln as fuel and reducer, occurs at ~57%. Not burned out coke fines are discharged with the clinker, which requires its additional processing for the carbon recycling. For about 21% of carbon is consumed for extraction of zinc, lead and iron from oxides. The rest amount of carbon (36%) is oxidized directly in the process of interaction with oxygen, which is supplied to the furnace as the part of air blowing. The excess amount of the coke fines is defined practically and can have significant differences during the charges of different content processing and different furnaces usage. The ways of decreasing of the coke fines consumption are based on the selection of charge composition and temperature condition, guaranteeing the material passing through the furnace in the strewing regime, which ensures the efficiency of reducing processes and heat recycling in the furnace. The largest amount of the furnace heat (43.8%) leaves the furnace with gases. The mounting of the waste-heat boiler behind the furnace makes it possible to save the costs for 20% of the charged fuel by means of steam generation. It is also prospective to heat the air, which comes into the furnace during the “dry” cooling of clinker. There is investigated the possibility of decreasing of the fuel consumption, which provides the internal recycling of heat in the furnace. It is possible to use the reaction heat for the heating of air, coming into the furnace by iron oxidizing. Iron is recovered in the furnace by fine cokes carbon in the content of reaction material. Feeding of steam into the furnace makes it possible to do the following operations:
– intensification of iron oxidizing process;
– encouraging of absorption and transportation of the heat, radiated by the heat material into the furnace depth;
– gasification of not burned carbon-containing fuel.
Usage of the high pressure air blowing makes it possible to intensify the oxidizing reactions of distilled metals in the furnace depth. These reactions are the internal source of heat.

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4. Panshin A. M., Leontev L. I., Kozlov P. A., Dyubanov V. G., Zatonskiy A. V., Ivakin D. A. Tekhnologiya pererabotki pyli elektrodugovykh pechey Otkrytogo aktsionernogo obshchestva “Severstal” v velts-komplekse Otkrytogo aktsionernogo obshchestva “Chelyabinskiy tsinkovyy zavod” (Technology of processing of dust of electric arc furnaces of “Severstal” JSC in the Waelz complex of “Chelyabinsk Zinc Plant” JSC). Ekologiya i promyshlennost Rossii — Ecology and industry of Russia. 2012. No. 11.