铜渣组分含量对渣锍高温沉降分离效果的影响

Influence of slag contents on sedimentation separation of slag and matte at high temperature

本文利用高温沉降实验对FeO-SiO2-Fe3O4-CaO-Al2O3-MgO系中不同组分含量以及温度对铜渣、铜锍分离效果的影响进行研究,同时利用热力学计算软件FactSage结合含固相熔渣的黏度、密度计算公式,对不同渣型炉渣的黏度和密度进行计算,进而研究其对渣锍分离效果的影响。结果表明,当炉渣黏度大于0.5 Pa·s时,黏度升高对渣锍分离有着十分不利的影响。当炉渣各组分控制在SiO2/Fe比(w(SiO2)/w(Fe))0.82%~0.97%、w(CaO)0~6.2%、w(Al2O3)2%~7%、w(MgO)0~1.25%和w(Fe3O4)0~10%,且沉降温度在1230℃以上时,熔渣具有良好的流动性,其密度也在理想的范围内,沉降后渣中的含铜量低于1%。由沉降后渣的矿相分析表明,难以沉降的铜物相主要为呈点状分布的微米级黄铜矿和少量大粒径的辉铜矿。

In this work, the influences of contents of slag component and smelting temperature on the slag/matte separation efficiency were studied in FeO-SiO2-Fe3O4-CaO-Al2O3-MgO system, using high temperature sedimentation experiments. The viscosity and density at different contents of slag component were calculated using FactSage thermodynamic software, cooperated with the formula for the viscosity and density of solid-containing slag, to investigate their effects on the slag/matte separation. The results show that when the viscosity of slag is higher than 0.5 Pa·s, the further increase of viscosity has an extremely adverse effect on the slag/matte separation. When the compositions of slag are SiO2/Fe ratio of 0.82%-0.97, w(CaO) of 0-6.2%, w(Al2O3) of 2%-7%, w(MgO) of 0-1.25%, w(Fe3O4) of 0-10%, and sedimentation temperature is above 1230 ℃, the molten slag shows good liquidity and its density is also in the ideal range, and the content of copper in the sedimentation slag can be lower than 1%. The mineralogical analysis for the sedimentation slag indicates that the copper loss in slag is primarily the punctiform chalcopyrite at micron scale and small amounts of larger-particle chalcocite.