Multi-parameter enhancement of membrane bioreactor process efficiency by biomass selection and selective biomass wasting

摘要

The present invention relates to a process and device for selectively removal of deflocculated sludge below a pre-selected size from a sludge mixed liquor. The invention resides in the concept of removing from the sludge mixed liquor deflocculated sludge. The removal is preferably carried out by a two-step separation providing a fraction comprising sludge flocs, substantially freed from deflocculated sludge, and a fraction containing mostly deflocculated sludge. The fraction comprising sludge flocs is returned into the sludge mixed liquor, while the fraction containing mostly deflocculated sludge is removed from the system.