We distinguish between fat separators and coalescence separators. The first type of separators is used wherever fat is insoluble in water and occurs in the form of sticky clods that are difficult to decompose, deposited on the walls of pipes. This results in unpleasant smell, corrosion of equipment and clogging of pipelines. This type of equipment is installed close to the source of contamination, e.g. at the outlet of sewage from the kitchen. Coalescence separators are used to purify rainwater and process oil derivatives, solids and suspensions.