Filtration (gravel/ sand filters)

Filters are often used in water treatment. In particular, various filtration methods or filter media are available for particle separation, which are based on the principles of the screening effect and surface or depth filtration. Depending on the water quality, filter material and other operating conditions, chemical or biological processes can also play an important role.
Sand (gravel) is often used as a filter medium. The filter systems consist of a container (e.g. made of steel, GRP or concrete), which is filled with filter sand and through which the water to be treated is passed. For this purpose, there is usually a nozzle at the bottom of the filter to retain the filter material when the water passes through. The particles to be separated are deposited in the filter bed / filter sand.
If the sand filters are used for de-icing and demanganing, the water is usually aerated first. As a result of the addition of oxygen, the dissolved iron and manganese compounds are oxidized and converted into insoluble compounds. An iron and manganese sludge is deposited in the filter bed.
  • Particle removal
  • Iron removal, manganese removal