REFRACTORY GOLD LIBERATION BY ULTRAFINE GRINDING AND ATMOSPHERIC OXIDATION

摘要

The paper deals with the problem of refractory gold-containing sulphide material processing. It is shown that such methods for fine gold liberation as autoclave oxidation, roasting or bacterial oxidation are characterized by a number of essential disadvantages, where the main ones are - considerable expenses for ore treatment and big environmental impact. The authors suggest an alternative method for gold liberation, which is based on LeachOx technology, and represents a combination of ultra fine grinding process with the consequent atmospheric oxidation and leaching. The theoretical justification of atmospheric oxidation was carried out, in the result of this the mechanism and the degree of sulphide minerals' oxidation was found out, the dependence of gold dissolution speed on the slurry content in liquid phase produced by grinding and oxidation was identified. The experimental data and results of pilot-plant testing are given and the most effective grinding and atmospheric oxidation mode is selected on this basis. The performed complex of research works allowed using the provided technology at the gold processing plant having capacity of 8 min. tons of ore per year.