A method for the direct selective selection of a desired low sludge index in continuous activated sludge processes

摘要

A process for the treatment of waste water in continuous activated sludge treatment plants with at least one basin of a biological clarification stage and a secondary clarifier with a feed, characterized by a) taking off the settling and / or settled sludge fraction with high sludge index as surplus sludge, from at least one edge region of the secondary settling tank, which feeds the B) introducing the remaining sludge fraction depositing and / or settling in the region of the feed into at least one basin of a clarifier upstream of the secondary clarifier, c) determining the sludge index in the at least one biological clarifier bed, d ) Repeat steps a) to c) until a predetermined low sludge index is reached in the at least one biological treatment stage.