Development of Hydrometallurgical Treatment of Steel-making Dust

用硫酸和盐酸对炼钢粉尘进行了浸出，并对其浸出动力学进行了研究。将含锌优质炼钢粉尘粉碎至- 200目，在不同条件下进行金属提取，并对锌、铁、铅的浸出率进行了研究。弱浸条件下，锌的浸出率约为80%，但铁的浸出率低于10%。铁的浸出在很大程度上取决于酸浓度和浸出温度等浸出条件。铅在硫酸中浸出量很小，在盐酸中优先浸出。这可能是由于铅在这些酸中的溶解度不同所致。浸出速率服从对数函数规律，符合体积反应模型的要求。对炼钢粉尘进行了硫酸化焙烧，并对焙烧后的粉尘进行了碱浸。将粉尘置于氧气和二氧化硫混合气体中焙烧，研究其特性变化。当粉尘在600℃的氧气和二氧化硫混合气体中烘烤时，几乎所有的锌都被烧碱溶液浸出。硫酸化焙烧和烧碱浸出可有效地从粉尘中选择性浸出锌和铅。

The leaching of steel-making dust with sulfuric acid and hydrochloric acid has been conducted, and its kinetics has been studied. High grade steel-making dust in zinc were crushed to minus 200 mesh, and treated to extract metals under several conditions, and leaching percentages of zinc, iron and lead were investigated.The extraction degree of iron is less than 10% even when zinc is leached out about 80% by the weak leaching condition. The leaching of iron largely depends on leaching conditions such as acid concentration and leaching temperature. The extraction of lead is very small in the sulfuric acid, while lead is preferentially leached in the hydrochloric acid. This fact may be attributed to the difference of the solubility of lead in these acid. The leaching rate obeys the logarithmic function rule, which is expected to the volume reaction model.Sulfating roasting of steel-making dust has been conducted, and caustic soda leaching of the roasted dust has been done. The dust was roasted in the mixed gas of oxygen and sulfur dioxide, and the characteristic change was investigated.When the dust is roasted at 600℃ in the mixed gas of oxygen and sulfur dioxide, almost all zinc is leached out by caustic soda solution. For selective leaching of zinc and lead from the dust, sulfating roasting and caustic soda leaching is effective.