This article introduces working principle of gold wash plant, it is for extract gold from placer gold mining or alluvial gold mining plant.
Trommel wash plant working principle
A trommel is composed of a slightly-inclined rotating metal tube (the ‘scrubber section’) with a screen at its discharge end. Lifter bars, sometimes in the form of bolted in angle iron, are attached to the interior of the scrubber section. The ore is fed into the elevated end of the trommel. Water, often under pressure, is provided to the scrubber and screen sections and the combination of water and mechanical action frees the valuable minerals from the ore. The mineral bearing ore that passes through the screen is then further concentrated in smaller devices such as sluices and jigs. The larger pieces of ore that do not pass through the screen can be carried to a waste stack by a conveyor.
Detailed steps of gold wash plant procedure
Before entering hopper of trommel, raw materials are sent to the grizzly to separate large rocks, if any. After materials enter the trommel hopper, often with high pressure water pipe around the hopper to help feeding, the materials will be fully washed at the first section scrubber part, materials will be fully turned and separated inside drum. There are blades inside the drum for breaking clay, then materials enters to double drum trommel. Deya designs and produces trommel with double drums, inside drum is welded by steel bars diameter 30mm to 50mm depends on size of the trommel. This drum is to separate gravels to protect outside drum. Outside drum with screen mesh, normally 5 mm or 8 mm depends on the gold particle size potentially contained. Large rocks are separated to end of the trommel, while slurry with gold particles flow to bottom of the trommel for further process to extract gold. In brief, above steps as follows:
- By excavators or wheel loaders for feeding the minerals to the hopper, if large rocks, add grizzly to separate them before entering hopper.
- By the help of high pressure water, materials enters scrubber part, the drum with blades break the hard clay(attached video from deya client’s feedback).
- Gold trommel screen with double sieves and high pressure water splash bars for screening and separating
- Oversize ores to be be discharged as tailing at the end of trommel, if contain large size gold, a jigger machine is needed(attached video from deya client’s feedback).
- Undersize ore slurry will be directed to centrifugal concentrator for fine gold recovery
- Vibrating sluice or fixed sluice box with plastic mat for coarse gold recovery
- Gold shaking table(attached video from deya client’s feedback) or panning for fine concentration.
- Multiple slurry pumps for supplying water
- Diesel generator set for supplying power to the whole wash plant, if no electricity
- Controlling cabin with buttons to control all the equipment
- Mobile base and wheels with towing mechanism to provide full mobility, easy to move from site to site
Typical way of process diagram for reference