含锌电炉粉尘水浸处理-真空碳热还原工艺

根据国家对绿色冶金的倡导,对如何高效无污染回收含锌电炉粉尘中的金属锌及K、Na元素进行研究,采用水浸预处理回收粉尘中K、Na元素,再进行真空碳热还原回收金属锌。试验结果表明,水浸最佳方案为固液比为1∶10(g/ml)、搅拌速度为300 r/min、水浸时间为70 min。此条件下,K元素浸出率达91.09%,Na元素浸出率达85.68%。通过FactSage 8.0软件模拟真空碳热还原电炉粉尘在不同含碳条件下热力学行为,并结合前期探索试验表明,水浸渣添加质量分数为10%的焦炭、还原温度为950 ℃、保温时间为60 min的条件下进行真空碳热还原试验可有效分离Fe、Zn元素,获得金属锌锭(Zn质量分数为98.15%)及高品质铁精粉(Fe质量分数为61.93%)。

Water leaching treatment-vacuum carbothermic reduction process of zinc-bearing electric furnace dust

Based on the national requirements of green metallurgy, aiming at recycling zinc and K, Na elements in zinc-bearing electric furnace dust efficiently and pollution-freely, water leaching pretreatment was adopt to recover K and Na elements in dust, and vacuum carbothermic reduction was adopt to recover zinc. The experimental results show that the optimal solution for water leaching is solid-liquid ratio of 1∶10 (g/ml), stirring speed of 300 r/min and water leaching time of 70 min. Under this condition, the leaching rates of K and Na are 91.09% and 85.68%, respectively. FactSage 8.0 software was used to simulate the thermodynamic behavior of vacuum carbothermic reduction furnace dust under different carbon distribution conditions. Combined with the preliminary exploration test, the results show that vacuum carbothermic reduction experiment can effectively separate Fe and Zn elements under the conditions of 10% coke added into water leaching slag, reduction temperature of 950 ℃ and holding time of 60 min. The metal zinc ingot (Zn mass fraction is 98.15%) and high quality iron concentrate (Fe mass fraction is 61.93%) are obtained.