Development and Introduction of Contemporary Technology of Gold Cyanide Leaching From Gravitational Concentrates

The problem of improving the efficiency of processing of rich gold-bearing concentrates is considered. A review and the critical analysis of existing ways of processing concentrates is provided. Special attention is paid to cyanide leaching that is a priority way of processing gold-bearing concentrates in gold-extraction plants using a cyanide cycle. As applied to the gravitational concentrate of Berezovsky Mine, measures are developed aimed at accelerating leaching of coarse gold. Features of gold dissolution using oxidizing agents as an alternative to oxygen are studied: hydrogen and calcium peroxides, and potassium bromate. Research and laboratory verification of technology of gold cyanide leaching with chemical activation of the process are performed. Based on research results, an operational section has been planned and introduced for processing of rich gold-bearing concentrates at the Berezovsky Mine enterprise. With the use of hydrogen peroxide compared with traditional conditions, the leaching rate for gold increases by a factor of 1.5–2. With an initial content in concentrates of 100–500 g/ton under comparable conditions, the content in tailings decreases from 10–15 to 1–3 g/ton. Commercial operation of the technology developed shows that gold extraction from concentrates reaches 98–99%, and at the same time loss of gold with dump tailings is reduced by 4 kg a year.