The iron in water quenched copper-containing slag was recovering with the process composed of property modification by low-temperature strengthening reduction and high temperature melting. Based on thermodynamic analysis, the effects of reducing agent and additives on the process of modification by strengthening reduction were systematically studied and analyzed in theory. Research shows that adjusting the basicity of slag and changing the slag composition can improve the kinetics of the reduction reaction, as well as destroy the dense structure of Fe—O—Si, resulting in the iron compounds converted into metallic iron. Meanwhile, CaO was combined with SiO2 to form CaO·SiO2 and iron particles were aggregated into larger grains, realizing the property modification by reduction, which resulted in an initial separation between iron and silicon, being beneficial to the subsequent process of high temperature melting. With the optimized process parameters, including reduction at the temperature of 1 250 ℃ for 30 min, with C/O ratio of 1. 5, alkalinity of 0.6, and content of Al2 O3 slag at 13%, the metalized pellets can be obtained with the metallization ratio at 88.43%, which is beneficial to the subsequent high-temperature melting process.%采用低温强化还原改性-高温熔分工艺回收水淬铜渣中的铁. 在热力学分析基础上,系统研究了还原剂和添加剂对强化还原改性过程的影响并进行了理论分析. 研究表明,调整炉渣碱度和改变炉渣物相组成,改善了还原反应动力学条件,破坏了Fe—O—Si的致密结构,将化合态的铁转变为单质形式的金属铁,同时CaO与SiO2 结合形成CaO·SiO2 ,铁颗粒聚集成较大晶粒,起到了还原改性的效果,初步实现了铁硅分离,为后续高温熔分过程创造了条件. 铜渣强化还原改性的优化工艺参数为:还原温度1 250 ℃,时间30 min,C/O比1.5,碱度0.6,炉渣Al2O3 含量13%,在此条件下,获得金属化率为88.43%的金属化球团,有利于后续高温熔分工艺的进行.
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