METHOD OF PROCESSING OXIDE RAW MATERIAL CONTAINING NONFERROUS METALS Russian patent published in 1998 - IPC

FIELD: nonferrous metallurgy. SUBSTANCE: method can be, in particular, used to isolate nonferrous metals from slags, slurries, cakes, and clinkers by performing their reductive melting. Oxide raw material containing nonferrous metals is melted in presence of metal smelt and carbon-containing reducing agent. Process is carried out in constant-current electric furnace containing metal and foamed slag oxide melts using consumable carbon hollow or solid electrodes. One or several single-pole electrodes are immersed into bottom metal melt and carbon-containing reducing agent in gas-carrier stream is supplied through canals of these electrodes. Amount of supplied agent ensures level of carbon in metal melt within the range of 0.05 to 5 wt %, while maintaining value of product of concentrations of carbon in metal melt and carbon in slag melt within the range of 12 to 80 (wt%)². Temperature of process ranges from 1250 to 1650 C. As carbon- containing reducing agent, solid and liquid carbon substances and, as gas carrier, air, nitrogen, natural gas, or natural gas-air conversion products are used. A part of carbon-containing reducing agent is introduced by directly charging it onto bath of foamed slag oxide melt. EFFECT: increased rate and degree of nonferrous metal reduction, reduced power consumption, and improved purity of isolated metals. 7 cl, 2 tbl, 3 ex