ACID OXIDATION PRESSURE LEACH OF SULPHIDE LOCKED GOLD ORE, THEN CYANIDATION OF SEPARATED AU-BEARING SOLIDS

摘要

A process for treating refractory ores combines pressure oxidation treatment of the ore with cyanidation and carbon-in-pulp recovery. Pressure oxidation is carried out under acidic conditions, at elevated temperatures and pressure. Before cyanidation, the oxidized slurry is subjected to a multiple stage washing operation to remove excess acid and heavy metals generated during the pressure oxidation. Such heavy metal removal lowers the subsequent cyanide usage and makes the process more economical. Cyanidation is carried out in a conventional manner, and it has been found that carbon-in-pulp recovery leads to greatly enhanced recovery of gold when compared to other conventional methods, such as zinc precipitation.