铜冶炼砷灰碳热还原提高脱砷率试验研究

Experimental Research on Increasing Dearsenic Rate by Carbon Thermal Reduction of Arsenic Ash from Copper Smelting

砷灰是某铜冶炼企业生产过程中产生的一种副产物,主要成分为三氧化二砷,由于砷灰中还含有一定量的有价金属,因此需要对砷灰进行脱砷后回收利用。该企业采用回转窑酸化制粒焙烧脱砷工艺,实际生产过程中脱砷率仅为80%,不利于脱砷渣的回收利用。为了提高砷灰的脱砷率,研究采用碳热还原工艺。试验研究了不同工艺参数对砷灰与煤粉混合后脱砷率的影响关系,得到最佳的工艺条件为:焙烧温度600℃,焙烧时间40min,配碳量15%,在此条件下砷灰脱砷率达到了95.08%,提高明显。

Arsenic ash is a by-product produced in the production process of a copper smelting enterprise.The main component is arsenic trioxide.Since arsenic ash also contains a certain amount of valuable metals,it is necessary to recycle the arsenic ash after arsenic removal.The company uses a rotary kiln acidification granulation roasting process to remove arsenic,and the arsenic removal rate in the actual production process is only 80%,which is not conducive to the recycling of arsenic removal slag.In order to improve the arsenic removal rate of arsenic ash,the carbothermal reduction process has been studied.The experiment has studied the influence of different process parameters on the arsenic removal rate after mixing arsenic ash and coal powder.The optimum process conditions were obtained as follows:roasting temperature 600℃,roasting time 40min,15% carbon content.Under these conditions,arsenic ash removal rate reached 95.08%,which significantly improved.