Gold ore flotation method is a method with mature production technology and reasonable equipment configuration, which is suitable for gold-bearing sulfide minerals with high floatability. Here we will introduce the gold ore flotation stages and introduce five commonly used gold ore flotation methods.
1. Crushing
The raw gold ore is fed into the jaw crusher by the miner for coarse crushing. The coarsely crushed products are sent to the screening workshop by belt conveyor.
2. Screening
Double-layer vibrating screens are used to divide the coarsely crushed products into three levels. The products on the screen are larger in size and need to be returned to the jaw crusher for continue crushing;
The products of intermediate grade are fed into the cone crusher by the belt conveyor for secondary and fine crushing, and the products are returned to the screening workshop;
The particles of the product under the screen are relatively fine, and it is sent to the powder ore bin without further crushing.
3. Grinding
Classifier and ball mill, or hydrocyclone and ball mill, constitute closed-circuit grinding configuration. The number of grinding stages is determined according to the required product particle size, which can be either one-stage grinding or two-stage grinding. Grid ball mill is used for primary grinding and an overflow ball mill secondary grinding.
4. Flotation
The overflow of the classifier or hydrocyclone enters the agitation tank with flotation agent added. After stirring evenly, the slurry is sent to the flotation machine for flotation.
5. Concentration and filtration
The flotation underflow is transported to the tailings pond through the slurry pump, and the flotation foam product is concentrated and filtered to obtain the final gold concentrate.
1. Flotation + Flotation Concentrate Pyrometallurgy Method
This is the flotation method used by most gold-bearing polymetallic sulfide ores. In the flotation process, gold will enter the copper concentrate or lead concentrate that is closely symbiotic with it. The product is copper-gold concentrate or lead-gold concentrate, and then the copper-gold concentrate, lead-gold concentrate obtained by flotation is sent to a smelter. Gold is finally recovered during the smelting process.
2. Flotation + flotation concentrate cyanidation method
A small amount of concentrate is obtained by flotation of the sulfide ore containing gold quartz veins, and then cyanidation is carried out. The cyanidation process of flotation concentrate does not require fine grinding, so it has some advantages like less power consumption, small plant area and less capital investment.
3. Flotation + concentrate calcination + calcine cyanidation method
Flotation is used to treat insoluble gold-arsenic ore, gold-zinc ore and gold-pyrite with particularly high sulfide content, and calcination is used to remove harmful arsenic, antimony and other elements in the cyanidation process.
4. Flotation + tailings/middling cyanidation + concentrate calcination cyanidation method
It is suitable for separating quartz sulfide ore or gold-bearing pyrite and pyrrhotite ores from gold, pyrrhotite, chalcopyrite and other sulfide minerals.
5. Raw ore cyanidation + cyanidation tailings flotation method
When the cyanidation method cannot completely recover the gold coexisting with the sulfide minerals, the gold recovery rate can be greatly improved by first cyanidation treatment and then flotation process.
