Comprehensive Recovery of Multisource Metallurgical Solid Wastes: Coupling Modification and Carbothermal Reduction of Converter Slag and Copper Slag

The recovery of valuable metals in multisource metallurgical slag is conducive to achieve resource recycling and slag utilization. The method of coupling modification and carbothermal reduction of converter slag and copper slag as well as the migration of elements and changes in mineral phases in the process were studied. Based on the element mapping of modified slag, under the interaction of converter and copper slags, Fe₂O₃ and ‘FeO’ could be separated from the relevant structures of the two slags. The reduced metal phase of the modified slag was Fe-Cu-Mn-P crude alloy, and XRD detection of the reduced slags indicated a complex characterization. The factors of the reduction temperature, the modified basicity, and the C/O ratio on the recovery degree of Fe, Cu, Mn, and P were studied, and the optimal technical parameter was determined as 1773 K, 1.0, and 1.0, respectively.