What is the placer gold beneficiation process？

Placer gold is divided into channel gold, sedimentary placer gold, and mountain placer gold. What they all have in common is single-separated gold. This kind of gold can be extracted directly without grinding by crushing and ball milling. In the placer gold beneficiation process, production practice shows that ore washing and grading are very critical links. The ore washing is not clean, the metal loss is serious, and the mud mass destroys the sorting operation, resulting in a reduction in recovery rate and gold output. The classification is not good, the coarse and fine grains are mixed, and the sorting effect is not good. On the basis of systematically analyzing the particle size composition of ore and the distribution rate of gold, a feasible ore washing and grading plan should be formulated in combination with the specific conditions of each ore point.

Placer gold usually does not require crushing and grinding. Compared with rock gold mines, it can save a lot of equipment investment and operating costs. The ore preparation work before gold processing is mainly screening, grading and washing. In order to divide the rock into individual particles and completely separate the valuable mineral particles, placer gold mines also need to have crushing operations, but generally do not need a separate process. If the placer gold deposit is mined by hydraulic mining, the rock fragmentation operation is basically completed during the mining process. With other mining methods, rock breaking and grading, and ore washing operations are often carried out in the same equipment (for example, vibrating screens or trommels).

Large pieces of gravel usually do not contain gold. Through grading operations, the ratio of the maximum particle size of placer gold to the minimum particle size of placer gold can reach several thousand times. Metal-free boulders and gravel can be separated, thereby reducing the volume of incoming material considerably.

Crushing operations need to consume a certain amount of power. The larger the material per unit weight, the higher the power consumption. According to the difficulty of material crushing and ore washing, the more viscous the material to be processed, the more power is required. Generally, it can be divided into easy-washable gravel-pebble mineral sands, moderately washable clay-less mineral sands and difficult-washable muddy clay-rich mineral sands.