Citation:
J. Martin. A new generation of Aerated Filter. 3rd International Meeting On Biological Aerated Filters (BAF3) - 3 March 1999, Cranfield University, UK
Abstract:
The use of the activated sludge process is a very well known technology. It is and has been used
very widely in full scale plants from its first development at the Davyhulme works in
Manchester. However this process becomes very difficult to upgrade or to extend in order to
ensure compliance with either more stringent discharge consent conditions or to achieve the same
quality of discharge where increasing flows are the problem.
This problem of upgrading or extension to existing works led OTV almost twenty years ago to
develop the bio-filter process. This process consists of essentially biological filters operating
either in the down flow or up flow mode, the main benefits of this system being they are compact
in their space requirements, together with their ability to combine both filtration and
aerobic/anaerobic bio degradation. They are used for the removal of suspended solids, COD,
BOD, ammonia (and nitrate) either in the secondary or the tertiary treatment stage, plus with the
use of a precipitating chemical, they can also be used for the removal of phosphates.
