铜富氧熔炼生产高品位冰铜过程热力学分析

A Thermodynamic Study of Copper Oxygen-Riched Smelting Process to Produce High-Grade Matte

富氧强化熔炼生产高品位冰铜已成为目前铜冶炼趋势,但由于其工艺特点,产生炉渣中的铜含量约为2%~4%.为了优化铜富氧熔炼工艺,降低冶炼过程铜损失,减少铜渣净化过程的负担,有必要对铜富氧熔炼生产高品位冰铜过程中的反应规律及熔体物理化学变化进行研究,这对铜冶炼具有重要意义.因此,本文以铜精矿为原料,采用Factsage软件针对铜富氧熔炼生产高品位冰铜过程进行热力学模拟.通过理论计算,研究了冰铜品位对熔体物相变化、熔渣中的化学溶解铜含量、尖晶石含量等各组分的影响.计算结果表明,在熔炼温度为1220℃,富氧浓度为73%,冰铜品位低于66%,熔渣中未出现尖晶石相;而随着冰铜品位增加,体系中氧势持续升高,熔渣中开始析出以FeO为主的尖晶石相,严重恶化铜锍在渣中的沉降和聚集条件.冰铜品位超过74%,炉渣中以CuO形式损失的铜将急剧增加,降低了冶炼铜直收率.

The production of high-grade matte by oxygen-enriched smelting has become the current trend in copper smelting,but owing to its process characteristics,the copper content of the generated slag is about 2%-4%.To optimize the copper oxygen-enriched smelting process,reduce the copper loss during smelting and the burden of the slag purification process,it is essential to study the reaction laws and physical and chemical changes in the melt during the production of high-grade matte by oxygen-enriched smelting,which is of great significance for copper smelting.Therefore,in this paper,a thermodynamic simulation of the process of producing high-grade matte by oxygen-enriched smelting was carried out by FactSage Software.Through theoretical calculations,the effect of matte grade on the variation of the physical phase of the melt,the chemical dissolved copper content in the slag,the percentage of spinel and other components were investigated.The calculation results indicated that at a melting temperature of 1220℃and an oxygen concentration of 73%,there was no spinel phase in the slag when the matte grade was lower than 66%.However,as the matte grade increased,the oxygen potential in the system continued to rise,and the FeO-based spinel phase began to precipitate in the slag,which seriously deteriorated the conditions for settling and aggregation of copper in the slag.With the grade of matte above 74%,the copper loss in the slag in the form of CuO will increase sharply,reducing the direct copper yield of the smelting.