利用铜渣制备铁硫合金的实验研究

Experimental study on preparation of Fe-S alloy from copper slag

火法炼铜过程中产生的铜渣含有较高的有价金属,结合前期实验研究,提出了利用铜渣、硫铁矿和增炭剂混合制备能消除沉降电炉炉结的铁硫合金的新方法。结合工业应用条件,控制碳的加入量使铜渣中的铁橄榄石还原成单质Fe和铁硅比为2.9的共晶体残渣,实现了渣与合金因密度和熔点差异自动分离。结合FeO-SiO2二元系相图,并利用XRD、XRF研究了最佳制备温度、保温时间、碳粒度、碳添加比对铁硫合金密度和残渣铁硅比的影响,分析了铜渣中Fe、Cu、Ni的回收效果。结果表明:最佳制备温度1350℃、保温时间30min、碳粒度小于96μm、碳添加比1.6,此时制备出的铁硫合金满足消除炉结要求,且残渣易分离;铜渣中Fe回收率为33.52%,Cu回收率为95.34%,Ni回收率为100%。

Copper slag produced during the process of copper smelting by fire process contains high valuable metal.Based on previous experimental study,a new method of preparing Fe-S alloy which can eliminate the settling furnace junction by using the mixture of copper slag,pyrite and carbon enhancer is put forward.Combined with the industrial application conditions,the iron olivine in copper slag was reduced to eutectic residue with simple substance Fe and iron-silicon ratio of 2.9 by controlling the amount of carbon,and the automatic separation of slag and alloy due to the difference of density and melting point was realized.Combined with the phase diagram of FeO-SiO2 binary system,the effects of optimum preparation temperature,holding time,carbon particle size and carbon addition ratio on the density of Fe-S alloy and the ratio of residual iron to silicon were studied by XRD and XRF,and the recovery effects of Fe,Cu and Ni in the copper slag were analyzed.The results show that the best preparation temperature is 1350℃,the holding time is 30min,the carbon particle size is less than 96μm,and the carbon addition ratio is 1.6.At this time,the prepared Fe-S alloy meets the requirements of eliminating furnace structure,and the residue is easy to be separated;the recovery of Fe,Cu and Ni in copper slag is 33.52%,95.34% and 100%.