Physical wrapped gold is a kind of refractory gold mine. Nowadays, gold is not only an international reserve asset and decorative supplies, but also has applications in many high-tech fields, such as electronic technology, aerospace technology and so on. With the increasing demand for gold, there are few easy gold mines. So how to deal with refractory gold ore has become an important topic. Next, I will introduce the treatment method of wrapped gold for you.
Physically wrapped gold is a kind of refractory gold ore. even after fine grinding, the refractory gold ore can not achieve effective cyanide leaching of gold. According to the mineral characteristics, it can be divided into sulfide ore, carbonated ore and hoofed ore.
There are three main reasons why such gold ores are difficult to cyanide leach:
1. Gold is mostly wrapped in associated and gangue minerals with fine particles;
2. The associated metal sulfide reacts with cyanide;
3. Conductor minerals lead to passivation of cathodic dissolution reaction of gold.
Cyanidation is an important modern wet gold extraction method. 80% of the world's gold output is produced by cyanidation. Although the high toxicity of cyanide has prompted researchers in various countries to develop non cyanide gold extraction methods, cyanidation is still a very effective gold extraction technology at present!
In view of the mineral characteristics of refractory gold ores, which are difficult to be extracted by direct and single means, scholars at home and abroad have explored a series of methods to improve the gold leaching rate by pretreatment of refractory gold ores on the basis of cyanidation. Therefore, pretreatment is an important means to treat refractory gold in parcels. Common pretreatment methods are as follows:
Roasting method
Roasting oxidation method is a traditional method to treat refractory gold ores, including traditional oxidation roasting, rich nutrient roasting, microwave roasting and so on. In essence, the refractory concentrate is roasted to oxidize the sulfide wrapped around the fine-grained gold, exposing or partially exposing the fine-grained gold, so as to improve the gold leaching rate. This method is simple to operate and has strong adaptability to raw materials, but the toxic gases such as arsenic and sulfur produced in the roasting process will increase the environmental protection pressure of enterprises.
Wet chemical method
In recent years, wet chemical method has become one of the pretreatment technologies widely concerned. In this method, a strong oxidant is added to the pulp system under normal pressure to oxidize the sulfide and carbon in the ore, so that the fine gold in it is exposed and dissociated. This method has low treatment cost and simple equipment, but it has high requirements for minerals and process conditions. In recent years, people have developed a variety of pretreatment processes. Due to their unique technical characteristics and adaptability, suitable pretreatment processes should be selected for the treatment of refractory gold according to the characteristics of ore minerals.
Alkali leaching method
If the gold concentrate contains a certain amount of antimony. Oxidation Roasting Pretreatment of gold concentrate alone can significantly reduce the content of arsenic in gold concentrate and weaken the influence of arsenic on gold leaching rate, but it can not eliminate the influence of antimony on gold leaching rate. Therefore, in order to eliminate the influence of antimony, the gold concentrate can be pretreated by alkali leaching first, and the influence of alkali leaching time and xa2s concentration on antimony removal rate can be investigated by single factor experimental method.
After beneficiation tests, determining the nature of wrapped gold, selecting one or more of the above methods for pretreatment, and then extracting gold by all slime cyanidation is an important means to deal with refractory gold ores such as wrapped gold.
