铜火法精炼炉高砷铜烟尘的低温真空蒸发预脱砷

Pre-removal of arsenic from high arsenic-copper fly ash in copper pyrorefining furnace by low-temperature vacuum evaporation

以铜火法精炼炉高砷铜烟尘为原料,采用低温真空蒸发法对烟尘中As进行预脱除处理。通过XRD、ICP-OES、SEM等分析手段分别对烟尘和蒸发产物的物相、化学成分和形貌等进行了分析,探讨了蒸发温度、残压、蒸发时间等对As及其他金属脱除率的影响。结果表明:在蒸发温度400℃、残压100 Pa、蒸发时间50 min的优化工艺条件下,在保证其他金属尽可能不被蒸发的同时,As的去除率可达61.50%;蒸发物为纯度较高(95.86%)的立方晶型As_(2)O_(3),可作为初级As_(2)O_(3)产品使用;其他有价金属在蒸发残渣中得到富集,便于后续的废酸浸出工艺回收。

The high arsenic copper fly ash from copper prefining furnace was treated by low-temperature vacuum evaporation method for As pre-removal.The phase,chemical composition and morphology of the fly ash and evaporation products were characterized by XRD,ICP-OES and SEM,and the factors affecting the removal rate of As and other metals were studied,such as evaporation temperature,residual pressure,and evaporation time.The results show that:Under the optimized process conditions of evaporation temperature 400℃,residual pressure 100 Pa and evaporation time 50 min,the removal rate of As can reach 61.50%while ensuring that other metals are not evaporated as much as possible;The evaporant is cubic type As_(2)O_(3) with higher purity(95.86%),which can be used as primary As_(2)O_(3) product;Other valuable metals are enriched in the evaporation residue,which is convenient for subsequent recovery by waste acid leaching process.