South America has abundant gold placer resources, but the grade of gold in placer gold ore is extremely low. In order to obtain high-grade gold, professional gold beneficiation equipment and professional gold selection process are needed.
The beneficiation workflow of placer gold ore mainly includes grinding, washing, screening, and gravity separation.
Gold placer contains a lot of weathered clay, which wraps the ore, some of which are larger than 100mm in diameter, so it is necessary to crush the ore in advance and grind it into small particles, otherwise, it is easy to be thrown away as a waste rock during the screening process.
After grinding, the ore is washed. The ground ore is also mixed with a lot of fine silt, the particle size is less than 0.1 mm, which will interfere with the real gold during the sorting process, so it must be washed with water, and then use a vibrating screen to screen out about 20-40% of the waste rock.
After that is the highlight of gold beneficiation, because the proportion of gold and sand is quite different, so our ideal gold beneficiation method is the re-selection method.
For mines with a relatively low grade of placer gold, chutes are often used in the roughing stage, jigs are used in the sweeping stage, and amalgam drums or shakers are used in the dressing stage.
a.Spiral Chute
According to the particle size, the spiral chute can be divided into the coarse-grained chute, ore sand chute, and ore slime chute. The main function of the coarse-grained chute is to sort the placer gold ore. The feeding particle size is above 2-3mm, and it can even give 100-200mm ore particles, but it can recover ore particles as small as 0.074mm.
The ore sand chute is suitable for processing 2-0.074mm gold ore, and the ore sludge chute is suitable for processing ore particles below 0.074mm.
b. Centrifugal Gold Concentrator
When the centrifuge rotates at a high speed, it generates a large centrifugal force, which strengthens the dressing process and enables the fine ore particles to be recovered more effectively.
C. Jig Machine
This jig machine is mainly used to deal with small particle size, and the beneficiation particle size range is between 20-0.074mm, which can be used for roughing gold placer.
D. 6S Gold Shaking Table
The shaking table has a stable gold dressing effect and is suitable for processing fine-grained minerals. It is very suitable for the dressing stage of gold mines. The shaking table can be divided into coarse sand bed, fine sand bed, ore mud bed, etc.
The particle size of the gold particles in the coarse sand bed is between 0.5-2mm, the particle size of the gold particles in the fine sand bed is between 0.074-0.5mm, and the particle size of the mud bed is in the range of 0.037-0.074mm.
The above gold dressing equipment used in our placer gold mine in the beneficiation process, the use of different suitable equipment at different stages can make our work more effective.
