Operation and Fundamentals of Direct Anode Copper Production From Matte

Copper matte converting is an essential process in copper pyrometallurgy. Replacing traditional batch converting in Peirce–Smith converters (PSCs), continuous converting is becoming a new trend. In this work, a thermodynamic modeling of the copper matte continuous converting process was carried out under actual production conditions. There were five phases in the process: copper matte, copper, Cu2O, slag, and gas. To directly produce anode copper, the continuous converting process was divided into an oxidation period and a reduction period. The multiphase transformation during converting was investigated. The thermodynamic equilibria of the Cu–Fe–S–O–Si system in the process were evaluated. The results showed that the maximum S and O content dissolved in copper was approximately 1 wt pct. The copper matte appeared when the P(S2) was higher than 1.58 × 10−6 atm at T = 1523 K. When P(O2) was higher than 9.55 × 10−5 atm, the Cu2O phase was produced at T = 1523 K. During the conversion of Cu2S to Cu2O dissolved in copper, P(O2) significantly increased, P(S2) rapidly decreased, and copper loss in the slag increased. Reducing the residual rate of oxidation slag and controlling the flow rate of natural gas could reduce the oxygen content in the anode copper and improve the grade of the anode copper.