Trommel is a rotating cylinder with holes that acts like a classifier, allowing only gold materials to pass through the holes, while the large materials go out of the machine.
It is used for mining operations of all sizes, but the main purpose is to separate gold by removing large pebbles, boulders and rocks.
The procedure starts when the gold bearing material enters the rotating drum. The rotating drum is mainly constructed of screen material, which allows the smaller gravel to fall freely into the sluice box.
The combination of rotating drum and high-pressure water enables the machine to break any dirt and clay inside the rotating drum. This action continues until the material is broken into small gold bearing pieces that can exit the gold trommel through the cylinder holes.(Robinson, 2014).
As the gold bearing material gets run through the drum, the smaller particles are able to flow through the screen material with which the drum is made, and then the material proceeds to the sluice box or even other systems of operation. The larger rocks run all the way through the trommel and are discarded(Nuggets, 2018).
The trommel itself does not separate out the gold. It is simply used to help separate and classify out the material for further process. On larger operations, the trommel is generally incorporated into an entire wash plant setup, so that the smaller material that drops through the trommel is run through is simple sluice system to capture the heaviest materials and discharge the lighter sands(How Does a Gold Trommel Work? Basic Mining Equipment Building, n.d.).
Why do you think it’s important to remove large rocks before trying to extract gold from gravel? Share your thoughts!
