BEHAVIOR OF ZINC IN OXIDE-SULFIDE MELTS

摘要

Studies into the effect of temperature (1200-1300°C), oxygen content of the gaseous phase (50% to 70% by vol.) and the composition of the sulfide melt of Cu - Fe - Zn - S system (40% to 60% Cu and 3% to 8% Zn by weight) on the degree of transfer of zinc to oxide melt under conditions of complete desulfurization have been carried out using methods of integrated thermal analysis and chemical analysis of smelting products. It has been found that depending on the smelting conditions the degree of zinc transfer into oxide melt varies from 61% to 100%. Investigations of zinc sulfide behavior under a layer of slag containing magnetite have shown that zinc sulfide dissolved in the slag is oxidized by magnetite to form zinc oxide and sulfur dioxide. Zinc oxide is reduced by ferrous iron contained in the slag resulting in zinc vapor formation. The constant of zinc evaporation rate from the melt is virtually dependent on the smelting temperature. The experimental results obtained in the process of the investigations have been used for selection of process conditions for pilot-scale tests of smelting of copper-zinc sulfide concentrates in molten bath.