How do specific water purification methods work?
1 Physical water purification Physical water purification is primarily concerned with filtration techniques. Filtration is a purification instrument to remove solids from liquids. There are several different filtration techniques. A typical filter consists of a tank, the filter media and a controller to enable backflow. Screens Filtration through screens is usually done at the beginning of the water purification process. The shape of the screens depends on the particles that have to be removed. Sand filtration Sand filtration is a frequently used, very robust method to remove suspended solids from water. The filter medium consists of a multiple layer of sand with a variety in size and specific gravity. When water flows through the filter, the suspended solids precipitate in the sand layers as residue and the water, which is reduced in suspended solids, flows out of the filter. When the filters are loaded with particles the flow-direction is reversed, in order to regenerate it. Smaller
