Complex Electro-Thermal Processing of Kazakhstan's Oxidic Zinc-Containing Ores of Achisay Deposit

摘要

In article the results of researches on electro-fusion of oxidic zinc ore of Achisay deposit in the arc furnace (11.5% of ZnO, 0.6% of PbO, 21.6% of CaO, 21.0% of Fe_2O_3, 5.9% of SiO_2) are presented. Influences of coke, limestone and quartzite on formation of calcium carbide and ferroalloys were determined. Two variants of fusion of furnace charge, consisting of ore, coke, quartzite and from ore, limestone, quartzite, coke were realized. Researches were carried out by a method of rotatable planning of experiments of the second order. On the basis of the executed researches it is established that production of calcium carbide with the greatest liter capacity (170-183 l/kg) is observed from the furnace charge containing 30-44% of coke and 0-11.3% of quartzite from mass of the ore, thus the formed ferroalloy on the content of Si concerns to ferroalloy of marks FS20 and FS25. At production of ferroalloy with the great content of Si (up to 45%) the liter capacity of calcium carbide decreases till 123 l/kg. At change in furnace charge of quantities of quartzite and limestone the production of calcium carbide with liter capacity 210-233.6 l/kg is observed from furnace charge, containing 0-8% of quartzite and 10-30% of limestone from mass of ore: extraction of Si into the alloy is 77-79.5%, and the produced ferroalloy contains up to 29% of Si. Irrespective of furnace charge structure the degree of extraction of Zn and Pb in fume exceeds 99.4-99.5%.