Wechat QR code
Wechat QR code
15311826613
Click to add WeChatThe gold in high-sulfur and high-arsenic gold ore is mainly contained in sulfide minerals (such as pyrite and arsenopyrite) as encapsulated gold. Directly treating this type of gold concentrate with cyanidation usually has a very low gold leaching rate (less than 5%). This is because the gold is encapsulated by sulfide minerals in microscopic and submicroscopic forms, which prevents the effective contact between the gold particles and the leaching solvent, thereby hindering the leaching of gold. This type of gold ore is a typical difficult-to-treat gold resource.
In order to effectively recover the gold in this type of ore, the ore must be pretreated and then gold leached.
Currently, the common pretreatment methods for difficult-to-select gold are: hot pressure oxidation method, roasting oxidation method, and physical oxidation method.
Hot pressure oxidation method: It is a process of hot pressure gasification in an autoclave using air (or oxygen-enriched). By heating and oxygenating, the crystals of sulfide ore and some gangue minerals are destroyed to expose the encapsulated gold, and then the gold is oxidized and leached to obtain gold concentrate.
Roasting oxidation method: is to aerate at high temperature to decompose the sulfide ore encapsulating gold into porous oxides, thereby exposing the gold and obtaining qualified gold by leaching.
Biological oxidation method: is to use natural microorganisms to select sulfur-loving and iron-loving ore strains, and after adaptive cultivation and domestication, in a suitable environment, use the direct effect of these microbial metabolism or the indirect effect of metabolic products to directly or indirectly oxidize and decompose the sulfide ore matrix, destroy the harmful components such as pyrite and arsenopyrite encapsulating gold, fully expose the gold, and create favorable conditions for subsequent hydrogenation.
The gold ore leaching process usually includes: ore preparation, heap building, infiltration leaching, heap washing and unloading, and gold recovery.
Ore preparation: In the ore preparation stage, the gold-bearing ore mined from the mining site needs to be crushed. The large pieces of ore are fed into the crusher for crushing to obtain small-sized gold-bearing ore, so as to increase the contact area between the ore and the leaching solution and improve the gold leaching rate.
Heap building: This stage is to pile the subsequent gold-bearing ore in a certain shape and size at one time.
Percolation leaching:After the gold-bearing ore is piled up, the leaching agent (such as dilute sodium cyanide solution or other alternative leaching agents) is evenly sprayed on the ore pile through the spray system. The purpose is to perform percolation leaching through the spray system. After the precious liquid is settled and clarified in the rich liquid pool, it is adsorbed by an adsorption tank, and then desorption and electrolysis are performed to obtain gold concentrate.
Washing and unloading:It is necessary to wash the pile in the yard to recover the residual gold and reduce environmental pollution.
The above is the process of leaching gold from high-sulfur and high-arsenic gold ore. If you want to obtain a more ideal leaching rate, you need to carefully control the leaching process, including the concentration of cyanide, pH value, temperature and leaching time, to maximize the recovery of gold and reduce the consumption of chemical reagents. For high-sulfur and high-arsenic gold mines, the leaching process may also need to consider how to effectively remove the effects of arsenic and sulfur to avoid problems in subsequent processes.
Consultation
153-1182-6613
Consult
Message
