Study on Technological Process Innovation of Non-Cyanide Leaching

Nowadays, there are many gold leaching processes, and the dominant one is cyanidation, but the virulence of cyanidation seriously endangers the environment and human health. In order to reduce environmental pollution and improve the recovery rate of gold, metallurgical workers put forward a variety of new gold leaching methods, which can be roughly divided into two types: one is to develop pretreatment technology on the basis of traditional cyanidation method; The other is non-cyanide leaching of gold. Based on the existing Non-Cyanide leaching technology, this paper puts forward the process innovation of Non-Cyanide leaching technology, thiourea method and dilute nitric acid pre-oxidation treatment process. The thiourea non-cyanide leaching system was investigated. According to the leaching situation of gold and silver in raw ore, the innovative scheme of gold and silver leaching technology was selected. Compared with other treatment methods, thiourea method and dilute nitric acid pre-oxidation treatment technology overcome the danger of high pressure, and the nitrogen oxide gas produced in the dilute nitric acid oxidation process can be recycled, which basically does not pollute the environment.