| Abstract Scope |
Increased low-grade copper concentrates containing impurities such as As, Pb, Zn are used in copper production. In copper smelting and converting processes, a large amount of flue dusts are collected from the waste heat boiler (WHB) and the electrostatic precipitator (ESP). The dusts consisting of Cu, Pb, Zn, As, Fe, Bi, Ag are presented in the forms of sulphate, sulphide and oxide. The complex combination of these minerals makes it difficult to recover the valuable metals from a single lead-reduction process. Different approaches have been compared through experimental studies and thermodynamic calculations to efficiently recover most of the valuable metals and obtain clean slag. It was found that leaching, oxidation and reduction are essential steps to fix arsenic and recover valuable metals. Optimum conditions for high temperature processes of oxidation and reduction have been proposed. Most of the Ag and Bi can be recovered from lead alloy. |