Sewage purification system - exposing effluent to oxygen or air supply over part of its circulation path

摘要

A sewage purification system uses an oval basin with a middle partition in which the sewage circulates. The effluent is exposed at one or more sections of its path to a supply of air or of oxygen and remains for the rest of its path exposed to the free atmosphere. This combines an economical utilisation of oxygen with an optimum purification efficiency and an adaptability to fluctuating working conditions.