Features of the presence of precious metals in the zinc production clinker

Abstract

The paper considers the features of gold deportments in technogenic raw materials – aged clinker of zinc production at the Belovsky zinc plant (Belovo, Kemerovo Region). The Belovsky plant operated from 1930 to 2003 using zinc concentrates from the Salairsky ore mining and processing plant. After the plant shutdown, clinker dumps were stored at the plant’s mill site and were repeatedly washed with acidic solutions to isolate copper. This form of storage and leaching led to the transformation of precious metal deportments in clinker, which currently makes it difficult to extract gold. The gold content in clinker is at the level of 2–3 g/t, which makes gold recovery profitable. The presence of carbon in clinker complicates the use of known methods of both analytical detection of gold and its recovery. A method is proposed for determining the deportment and content of gold taking into account the fact that gold may be present in the form of free fine gold, as well as gold finely disseminated in iron and its oxides, in sulfide phases, in the quartz-silicate part of clinker and in the carbonaceous phase. It was shown that gold deportments in clinker change depending on the storage conditions and preceding acid treatment, and this affects the choice of the material processing flow chart. The share of gold available for leaching is at least 40 %. The increased associativity of gold with the coal (flotation-active) phase and the sorption activity of coal significantly interfere with the study into the properties of gold deportments in clinker, which requires preliminary carbon removal.