Environmentally Friendly Pyrometallurgical Scheme for Vacuum Separation of Non-Ferrous Metals from Waste Products in Incineration Plants

Abstract

Residues from the municipal solid waste processed in incineration plants in European countries are an important raw material to obtain valuable components, including non-ferrous metals. State and private companies specializing in the processing of waste incineration slag as products most often receive concentrates of non-ferrous metals, which, on average, contain, in mass. %: 20÷60 Cu; 10÷30 Zn; 5÷15 Pb; ~ 1 Al; ~ 1 Sn; ~ 1 Fe, up to 50 g/t Аu and up to 3,000 g/t Ag. Concentrates are sent for processing to smelters without taking the cost of zinc into account. The paper presents the study on the separation of metallic zinc into a separate product (zinc concentrate) from the collective concentrate of non-ferrous metals by a vacuum-thermal method, the safest from the environmental point of view. The study was performed with non-ferrous metal concentrate of +0.3-0.8 mm in size, containing wt. %: 68.07 - Cu; 12.4 - Zn; 14.78 - Pb; 0.99 - Al; 1.2 - Sn; 0.15 - Fe, up to 2.0 kg/t - Ag. The material was heat treated at 800÷900℃ with the residual pressure in the system of less than 0.13 kPa. Zinc concentrate was obtained, containing more than 96% of the main component. At the same time, the Cu content increased by 14.09% in the residue from the heat-vacuum treatment. Other metals (Pb, Al, Sn) including noble metals were also concentrated in the residue. The results of the study show that it is possible to separate zinc into a separate product from non-ferrous metal concentrates containing more than 10% Zn in the initial material by the proposed method.

Dearsenation of Gold-Bearing Composite Concentrates without Forced Displacement in a Sublimator

“…We have not found analogs of such equipment. All technical solutions have patents from the Republic of Kazakhstan [53][54][55][56].…”