SEWAGE PURIFICATING EQUIPMENT AND METHOD AS WELL AS MULTIPLE-STAGE BIOLOGICAL WATER PURIFICATING SYSTEM

The proposed plant comprises a fill, fill retaining elements and an effluent water inlet system. This inlet system is made up of an air injector and/or water distributor spray heads. A preferred form of the proposed plant has a settling basin with settling and sludge collector sections, fitted with pump and recirculation pipework returning sludge to the effluent water inlet. - The proposed method involves aeration of the effluent water, leading to the decomposition of the organic pollutants. The active sludge is kept moving and part of the settled sludge is recirculated into the aeration space. Air is introduced by spraying the effluent water and recirculated sludge continuously into the aeration space. Sludge is moved downwards by gravity, such that part of the sludge and part of the effluent water are recycled continuously