Abstract:Based on characteristics of high-silicon and low-iron content in a copper oxide concentrate, influence of basicity and FeO content on slag morphology, melting point, density, viscosity and electrical conductivity was investigated by reduction melting experiment in a high-temperature muffle furnace. The results show that this system slag mainly exists in glassy phase of calcium silicate, with Mg, Al and Fe dispersed in it. With increase of basicity from 0.2 to 0.6, melting point and density of slag drop first and rise later, viscosity rises first and drops later, and conductivity shows an rising trend. However, with increase of FeO content from 6% to 10%, melting point and viscosity of slag show a dropping trend, and density and conductivity show a rising trend. The suitable basicity of this system slag is about 0.5, and FeO addition should be less than 6%. Melting temperature is of <1 250 ℃, viscosity is of <2 Pa?s (1 400 ℃), and density is of 2.6~3.0 g/cm3. Thus, grade of crude copper is 96.5% with copper yield of 98% above.