Comparison of gold recovery from refractory gold ore by different processes

A certain low grade gold ore is characterized by complexity in ore's property, difficulty in mineral processing and very strict requirement for environment protection. After years of research from laboratory test, pilot test to industrial test, a new biooxidation with high efficiency has been developed. The aim of the present investigation was to compare biooxidation and roasting as pretreatment process of a refractory gold-bearing pyrite, in order to increase the gold recovery during the subsequent conventional cyanidation. Experimental results have shown the technical feasibility of the biooxidative pretreatment prior to conventional leaching. A quite good metallurgical performance is achieved in commercial operation with environment-friendly result.