What are the combined sulfide gold beneficiation processes?

15311826613

Welcome to consult Xinhai - customized mineral processing plan

Xinhai can provide you with mineral processing tests, mineral processing process and mineral processing equipment selection, mineral processing plant scheme design and construction drawing design; provide mining mineral processing equipment; provide mineral processing plant construction and equipment installation as well as mine management and operation services.

Consultation 153-1182-6613

15311826613

Click to add WeChat

Get product price

WeChat ID has been copied, add friends, and get manufacturer quotations!

High sulfide gold ore contains a high proportion of sulfide minerals such as pyrite and arsenopyrite, in which the gold grade is relatively low, and the natural gold particle size is fine, usually tightly wrapped by sulfide minerals such as pyrite. The characteristics of this type of ore are that gold and sulfide are closely related, resulting in a low gold recovery rate in the direct leaching process, and high consumption and production costs of gold leaching agents. Therefore, for high sulfide gold mines, direct cyanide leaching is not recommended.

Flotation is a common process for treating gold-containing sulfide mineral ores and is widely used in gold ore dressing plants. It enriches gold into copper, lead, sulfur and other concentrates, and then extracts gold from these concentrates, which can not only achieve the comprehensive utilization of multiple metals, but also improve the recovery rate of gold. For gold ores containing non-ferrous metals in the original ore, flotation is an economical and reasonable process. In order to improve the return on investment, the combined beneficiation process of flotation and other processes can sometimes achieve more impressive results for ores of different properties.

1. Gravity-flotation process

Gravity-flotation process is suitable for ores where gold and sulfides are closely coexisting and gold can only be recovered by smelting, and is also suitable for gold-bearing quartz vein ores with uneven coarse grains. The original ore is flotated to obtain flotation concentrate. However, flotation tailings often contain sulfides associated with the gangue, and the coarse natural gold wrapped in these sulfides is not easy to be recovered by flotation. In order to effectively recover the gold, gravity separation equipment is used to first recover the coarse gold, thereby improving the gold recovery rate of the entire beneficiation process. Common gravity separation equipment includes jigs, shaking tables and spiral chutes.

2. Flotation-concentrate cyanidation process

Floatation-concentrate cyanidation process is often used to treat gold ores containing gold quartz veins and gold-bearing pyrite quartz veins. Usually, xanthate is used as a collector and pine oil is used as a frother to flotate in a weakly alkaline slurry to obtain gold concentrate. Subsequently, the flotation concentrate is leached by cyanide, the gold is dissolved by cyanide, the complex enters the solution, and then replaced with zinc powder to obtain gold mud, and then pure gold is obtained through pyrometallurgy. This process not only reduces the need for fine grinding of all ores, reduces power consumption and infrastructure investment, but also improves the recovery rate of gold.

3. Flotation-roasting-cyanidation process

For the treatment of complex ores such as insoluble gold-arsenic ore, gold-zinc ore and gold-pyrite with particularly high sulfide content, the flotation-roasting-cyanidation process is an effective comprehensive treatment process. When treating flotation concentrates with high arsenic and sulfur content, the cyanide tailings often enrich impurities such as sulfur, iron, and arsenic after flotation, forming high-sulfur and high-arsenic concentrates that are difficult to directly cyanide leached. To this end, these flotation gold concentrates are first oxidized and roasted, which can not only effectively remove arsenic and sulfur, but also make the roasted sand structure loose, which is conducive to the further leaching of gold and silver.

4. Flotation-concentrate thiourea leaching process

The flotation-concentrate thiourea leaching process is mostly suitable for treating vein gold ores with high arsenic, sulfur or carbon content. This process first uses flotation to enrich gold-containing sulfides into concentrates, and then uses thiourea for leaching. Thiourea acid solution has a rapid dissolution ability for gold and silver, and thiourea is less toxic and easy to regenerate. Thiourea leaching is not affected by mineral components such as antimony, arsenic, copper, and sulfur, which often interfere with cyanide gold extraction. Therefore, the thiourea leaching process can effectively extract gold and silver from gold-containing ore that is difficult to process by cyanide. Compared with cyanide gold leaching, the time required for thiourea gold leaching is greatly shortened, thereby improving the efficiency of gold extraction.

There are many types of gold ores, and their applicable beneficiation processes are also different. Therefore, before selecting a beneficiation process, it is necessary to conduct a beneficiation experiment analysis on the ore, and customize a suitable gold ore beneficiation process based on a scientific and reasonable test report. This method can not only improve the extraction efficiency of gold, but also reduce production costs, realize economical and environmentally friendly mining, and thus achieve an ideal recovery rate.