3 Gold Extraction Processes of Arsenic Gold Ore

The gold in arsenic-bearing gold ores is closely symbiotic with arsenic-bearing minerals and pyrite, and gold is wrapped in fine particles, which is also the main reason for the refractory treatment of arsenic-bearing gold ores.

In order to improve the recovery rate of gold, it is necessary to remove arsenic from arsenic gold ores. Common arsenic gold ore beneficiation processes include oxidizing roasting process, pressurized oxidation process and bacterial oxidation process.

Oxidizing Roasting Proces of Arsenic Gold Ore

The principle of the oxidative roasting process is that under high temperature conditions, arsenic and sulfide in the gold ore will react with oxygen to form new oxides, thereby destroying the encapsulation of fine-grained gold, so that the gold is exposed to the cyanide leaching solution to the maximum extent, which can improve the recovery rate of gold.

During the roasting process, a large amount of toxic gases such as sulfur dioxide and arsenic trioxide will be released. Although the sulfide and arsenic produced by roasting can be recovered, a small part of the gas will still be discharged to cause environmental pollution.

The evaporation rate of arsenic in the oxidative roasting method is more than 99%, and the recovery rate of arsenic is 90%.

Pressurized Oxidation Proces of Arsenic Gold Ore

The pressurized oxidation process is to add oxygen to the acidic or alkaline slurry of arsenic-gold ore to oxidize arsenic and sulfur. In this way, the structure of the main gold-carrying minerals such as arsenopyrite and pyrite can be destroyed, and the encapsulated fine-grained gold can be released, providing good process conditions for subsequent cyanidation leaching.

The pressurized oxidation method has a high recovery rate, strong adaptability to arsenic and sulfur grades, and low environmental risks, but the cost is slightly higher.

The recovery rate of arsenic-gold ore treated by this method can be increased from 5-74% to 87-99%.

Bacterial Oxidation Proces of Arsenic Gold Ore

Bacterial oxidation process means that in the process of oxidation, bacteria use iron and sulfur in ore as energy materials to meet their own metabolic needs, so as to achieve the purpose of removing arsenic and desulfurization.

The bacterial oxidation method is simple to operate, has high gold recovery rate and strong adaptability, but has a long treatment period.

The above three methods are commonly used arsenic removal methods for arsenic-containing gold ores.

Among them, the oxidation roasting method is widely used, but the bacterial oxidation method has a better development prospect.

Which treatment method to choose for arsenic gold ore needs to be determined according to the specific mineral composition and ore properties.