The gold washing equipment mainly uses the washing and infiltration of water to expand and disperse the clay, so as to realize the separation of t soil and gold. Common gold washing equipment mainly includes the followings.
Spiral Washing Machine
The spiral washing machine is suitable for the cleaning of gold ore with high mud content. It uses the buoyancy of water to separate dust and impurities from placer gold. After the agitation of the spiral blade, the purpose of filtering water to remove impurities, lifting and conveying is achieved. And in the process of lifting, the mixing work is also carried out, so that the sand is evenly stirred, and there is no distinction between fine and coarse sand. The spiral washing machine has the characteristics of long spiral body, good sealing system, simple structure, large processing capacity, convenient maintenance, low water content and low mud content in sand production.
Trommel Screen
Trommel screen is widely used in all kinds of hard - to - wash bulk ore. It can divide the washed material into +40mm and -40mm products. The -40mm product can be further scrubbed by the double spiral groove washing machine, and the material can be divided into +2mm and -2mm two-level products, and the washing efficiency can reach about 98%. This combination is the most effective method for refractory ores at present.
Groove Washing Machine
The groove washing machine is widely used for washing various easy-to-wash and difficult-to-wash ores. More than 20% mud content in the ore will block the crusher and chute. Groove washing machine can screw stirring and scrubbing ore with mud content of more than 20% to achieve the purpose of separating gold from mud. The cleaned gold ore is discharged from the discharge port, and the muddy water is discharged from the tailings end.
Jig
The jig stratifies the mineral particles of different specific gravity according to specific gravity, the minerals with small specific gravity are located in the upper layer, and the minerals with large specific gravity are located in the lower layer. The layered materials are discharged separately by the action of machinery and water flow. Jig has the advantages of simple operation and large processing capacity, and has good application effect in roughing gold ore.
Shaking Table
The shaker mainly uses the transmission mechanism to drive the bed surface for longitudinal reciprocating motion. In the reciprocating process, the ore particles are subjected to the layering action perpendicular to the bed surface and the layering action parallel to the bed surface, so that materials of different particle sizes are discharged from the interval of the bed surface to achieve separation. It is suitable for processing gold minerals with finer particle size.
Spiral Chute
Spiral chute is a beneficiation equipment that uses inclined water flow for separation. Under the action of water flow, the ore particles settle in different areas of the tank according to their specific gravity. Mineral particles with a small specific gravity are carried away by the water flow, leaving behind the particles with a large specific gravity. The spiral chute is suitable for processing fine-grained gold ore with low mud content, and the ore particle size is between 0.03~0.6mm.
The washing and dressing of gold mines are not accomplished overnight, it needs reasonable processes and steps.
Screening
Alluvial gold mine often contains large gravel, which will affect the efficiency of alluvial gold washing and damage the equipment of the gold washing plant. Therefore, the first process of the gold washing plant is to screen the gravel in the gold ore. During the screening process, the soil on the gravel surface needs to be washed with water to ensure that the soil is flushed under the screen.
Desliming
The effect of large gravel on gold washing plant has been removed after coarse screening. The second process is desliming, which is to fully dilute the gold and soil in the placer through water washing and mechanical scrubbing, so as to prevent the gold from being wrapped in the soil, so that the gold can be freed. Cylinder washing machine or spiral washing machine is often used to deal with placer gold with high mud content, and drum washing machine is often used to wash gold with low mud content.
Gravity Separation
Gravity separation is the most common method to process alluvial gold, and the equipment used are chute, jig, shaking table, centrifuge, and so on. Among them, chutes and jigs are often used for roughing operations, and shaking tables and centrifuges are mainly used for concentration operations.
Concentration
The main methods of alluvial gold concentration are gravity separation and amalgamation. Gravity separation method is to use shaking table or centrifuge to enrich and purify the coarse concentrate in jig and chute in the next step. The shaker can obtain the final high-purity gold powder, but the loss rate is high. The enrichment of the centrifuge is relatively large, but pure gold cannot be obtained. Therefore, some mines still choose the amalgamation method in the concentration process of placer gold mines. However, due to its serious environmental pollution, it was gradually stopped by the environmental protection department.
