PROCESSING OF TECHNOGENIC WASTE FROM THE MINING AND METALLURGICAL COMPLEX BY BIOLEACHING

The study considers technogenic waste from the mining and metallurgical complex of the Republic of Kazakhstan as a promising secondary source of non-ferrous and rare metals. The object of investigation was copper ore tailings from the Balkhash Concentration Plant, characterized by a silicate matrix (Si ≈ 36%) and the presence of residual amounts of Cu (≈0.32%) and Zn (≈0.77%). A comprehensive analysis of their chemical, granulometric, and physicochemical composition was carried out using the ICP-OES method. The processes of raw material preparation, including crushing, grinding, and classification, were studied, and the grinding conditions were optimized. It was shown that reducing the particle size to < 40 µm is a critical factor for enhancing leaching efficiency. An integrated processing technology combining microfluidic separation and bioleaching is proposed. It was established that microfluidic separation provides selective concentration of copper up to 0.52-0.58% in the target fraction with a recovery of 70-75%. Bioleaching under optimal conditions (pH 1.8-1.9; T ≈ 31-32 °C) ensures copper recovery up to 60-63% and zinc recovery up to 55-58%. The obtained results confirm the potential of bioleaching for the integrated processing of technogenic waste and the reduction of its environmental impact.

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