Soil washing

The operating principle of our soil washing systems is to concentrate pollutants to a small mass fraction, which is then separated so that the majority of the feed material can be recycled.

As the pollutants are usually located on the surface of each individual grain or particle, they must first be broken down and then separated by abrasion.

For this purpose, the coarse impurities such as wood, plastic or plant residues are first separated from the minerals and in the next step the lumps of clay or strongly adhering components are dissolved by a washing drum or a sword wash. The particles are then separated into different grain sizes (sands and gravels) and subjected to separate density separation. Depending on the grain size, different devices are used for this purpose, such as DMS, Jig or Sorting spirals. The cleaned products are dewatered separately and stored temporarily for reuse or reintroduction.

As the contamination is concentrated in the wash water or in the finest sludge at the end of the washing process, it is particularly important to keep this proportion as low as possible. Separation with high-performance cyclones to ~ 15 µm and subsequent sludge thickening using clarifier thickeners and dewatering using chamber filter presses or centrifuges has proven successful here. At the end, the wash water is purified, for example using activated carbon filters or further chemical treatment, and fed back into the process.