Washing trommel, or trommel washer, or washing drum, is a type of screening equipment that is extensively used in the mining industry. It is a cylindrical tube that cleans a particular material (gold in most cases) by removing the unnecessary compounds. The washing trommel is most commonly used for mining applications. There are several trommel models on the market, and every trommel is used for a specific application. The medium-sized trommels are used for lighter jobs, while the larger-sized washing trommels for commercial mining. There is even a portable washing trommel that is exclusively used for gold extraction.
The first trommel was invented many years ago by the Ancient Greeks. It was used for pulling water out of the river Nile and later it was widely used for removing water out of ships. The early trommel was also used as a hand pump. Today, most trommels use the same working principle which was developed many years ago. The washing trommels that work by using the Archimedes method, are most commonly used for washing machine parts and for gold extraction.
This unique mining machine is designed with a purpose to efficiently clean materials from unneeded compounds by applying high pressure water. The process takes place into the drum of the washing trommel. The washing trommel comes with blades inside the drum for more effective cleaning. The friction that is created between the granulometries when the material is tossed, dissolves all the adhered impurities. The washing process of the washing trommel ends by rinsing the final material with clean water.
The large washing trommels which are used for commercial mining are generally used for washing fine compounds from gravel, coal and iron ore. The Archimedes washing trommel can be adjusted with a screw inside the drum, featuring threads or ridges. The threads are specifically positioned to allow pieces of gold or machine parts to be cleaned and extracted easily. As the materials pass through the threads downwards, they are being washed and separated. In the cylinder, there are special lifters which lift and mix the materials in the washing process.
In some washing trommels, the angle is set upwards. When the drum is spinning, the threads carry the material upwards. As the material is traveling, it is being sprayed with specific cleaning fluids for dirt and grease removal. The cleaning fluids efficiently remove any dirt, gravel or other unnecessary compound from the material. Then, the removed dirt or gravel is thrown from the trommel.