Gold beneficiation
Refractory gold resources can generally be divided into three main types:
The first type is high arsenic, carbon, and sulfur type gold ore. In this type, the arsenic content is more than 3%, the carbon content is 1-2%, and the sulfur content is 5-6%. Using the conventional cyanide gold extraction process, the gold leaching rate is It is generally 20-50%, and a large amount of Na2CN is consumed. When enriched by flotation technology, although a higher gold concentrate grade can be obtained, the concentrate contains high levels of harmful elements such as arsenic, carbon, and antimony. It will have an impact on the next step of gold extraction process.
The second type is gold-containing ores in which gold is wrapped in gangue minerals and harmful impurities in fine particles and microscopic forms. In this type, the metal sulfide content is small, about 1-2%, and is embedded in the gangue minerals. The fine gold particles in the crystals account for 20-30%. Conventional cyanide extraction or flotation enrichment methods are used to extract gold, but the gold recovery rate is very low.
The third type is gold ore with a close relationship between gold, arsenic and sulfur. Its characteristic is that arsenic and sulfur are the main carrier minerals of gold, and the arsenic content is medium. The gold leaching index of this type of ore using a single cyanide gold extraction process is relatively low. If gold is enriched by flotation, a higher recovery rate can be obtained, but it is difficult to sell because it contains excessive arsenic.
mining technology
chemical selection
1. Gold mineralization and separation
The chemical beneficiation methods of gold mines mainly include warm water method and cyanide method. The mixed method is relatively old and suitable for coarse-grained single gold. However, it is relatively polluting and has been gradually replaced by wisdom. There are two cyanidation methods, stirring cyanidation and percolation cyanidation.
2. Chemical and gold selection equipment
The chemical method is used to select gold ore, mainly the atmosphere method. The equipment used includes zinc powder exchange device, leaching stirring tank, etc. The zinc powder replacement device is a device that replaces gold mud from the leachate with zinc powder.
The leaching stirring tank is a device for stirring the slurry. When the ore particle size is below 200 mesh and the solution concentration is below 45%, a suspension can be formed to increase the concentration of dissolved gold in the adsorption tank and accelerate the leaching time.
Post time: Jan-10-2024
