含金砷硫精矿烧渣炼铁富集金的研究

Enriching gold by iron-making from roasting cinder of sulfur concentrate containing gold and arsenic

提出一种处理含金砷硫精矿的新工艺,主要包括焙烧脱除硫砷—烧渣炼铁富集金—电解分离铁金等工序。对其中烧渣炼铁富集金进行实验研究,研究熔炼中C与O质量比与炉渣二元碱度(即CaO与SiO2质量比)、熔炼温度和熔炼时间对铁和金回收率的影响,确定最佳条件及在此条件下所得生铁的化学成分。研究结果表明:在C与O质量比为0.93、炉渣二元碱度为1.0、熔炼温度为1 500℃、熔炼时间为90 min的最佳条件下,铁和金的回收率分别达到97.49%和99.10%,所得生铁中金质量分数为16 g/t,与烧渣金质量分数相比约提高0.63倍,铁质量分数为97.27%,碳质量分数为1.38%。

A new technology, which was composed of three main processes, i.e. roasting to remove sulfur and arsenic, iron smelting from the cinder to enrich gold, and electrolysis to separate iron and gold, was proposed for the treatment of sulfur concentrate containing gold and arsenic. The processes of iron-making by reduction smelting were investigated experimentally. The effects of mass ratio of carbon to oxygen together with slag binary basicity, smelting temperature and smelting time on the recoveries of iron and gold were evaluated, and the optimal conditions were determined. The results show that the optimal conditions are as follows： mass ratio of carbon to oxygen is 0.93, slag binary basicity is 1.0, smelting temperature is 1 500 ℃ and smelting time is 90 min. Under the optimal conditions, the recoveries of iron and gold reach 97.49% and 99.10%, respectively, and the composition of pig iron obtained is analyzed chemically to be as follows： gold 16 g/t, iron 97.27%, and carbon 1.38%. The gold content in the pig iron increases by about 0.63 times than that in the cinder.