Implementing biofilm carriers into activated sludge process - 15 years of experience

摘要

Seven full-scale hybrid systems have been operating in waste water treatment plants in Southern Germany since the early eighties. The aerobic submerged biofilm technology applied is known as Bio-2-Sludge process. The plants have originally been designed for carbon removal and were modified later on to allow nitrogen removal. For this purpose, the age of the operating sludge had to be raised. This was achieved without any addition of reactor volume by installation of submerged biofilm carriers. The use of the submerged, fixed bed devices results in a very efficient sludge, allowing MLSS of up to 11 g/l. Operational results show both a purification improvement of BOD and ammonia and the existence of simultaneous denitrification. Practical experiences of long-term operations are being reported. (C) 1998 IAWQ. Published by Elsevier Science Ltd [References: 19]