从铜冶炼阳极炉精炼渣中提取铜工艺研究

Study on copper extraction from refining slag of copper smelting anode furnace

采用废酸氧化浸出、CaO焙烧浸出渣、废酸氧化浸出焙砂的火法—湿法联合工艺提取铜冶炼阳极炉精炼渣中的铜。详细研究了废酸直接氧化浸出精炼渣时,浸出温度、液固比、时间、通入空气量对Cu、Fe、As等浸出率的影响,以及焙烧温度、时间、浸出渣与CaO质量比(m(slag)/m(CaO))对Cu、Fe、As等浸出率的影响。结果表明:废酸直接氧化浸出时,浸出温度90℃、液固比9 mL/g、时间4 h、每升溶液通入空气量200 mL/min条件下,Cu、Fe、As的浸出率分别为85.32%、68.41%、44.97%。浸出渣与CaO混合后,在温度800℃、时间4 h、浸出渣与CaO质量比为5.1的条件下进行焙烧,得到的焙砂经过废酸氧化浸出,精炼渣中的Cu、Fe、As的总浸出率分别达98.10%、69.60%、50.48%。

The combination of pyrometallurgy and hydrometallurgy processes, including oxidation leaching by waste acid, CaO roasting leaching slag and oxidation leaching product of roasting by waste acid, were applied to extract copper from the refining slag of copper smelting anode furnace. Detailed studies were conducted on the effects of leaching temperature, liquid-solid ratio, leaching time, and air flow on the leaching rates of Cu,Fe, As, as well as the calcination temperature, time, and mass ratio of leaching slag to CaO(m(slag)/m(CaO)) on the leaching rates of Cu, Fe, As, when waste acide is directly oxidized to leach refining slag. The results show that during the direct oxidation leaching of waste acid, the leaching rates of Cu, Fe and As are respectively 85.32%, 68.41%, and 44.97%, under the conditions of a leaching temperature of 90 ℃, liquid-solid ratio of 9 mL/g, time of 4 h, and air flow per liter of solution of 200 mL/min. After being mixed with CaO, the leaching slag is baked at temperature of 800 ℃, time of 4 h, and the mass ratio of leaching slag and CaO of 5.1. The resulting baked sand is leached by waste acide oxidation, and the total leaching rates of Cu, Fe and As can reach 98.10%, 69.60% and 50.48%, respectively.