Full scale case studies of a simplified aerated filter (BAF) for organics and nitrogen removal

The limitation of available land for wastewater treatment facilities has challenged environmental engineers in searching for efficient and effective treatment systems that will minimize space requirements for waste treatment. To meet these requirements, a fixed film biological process using a DeepBed TM filter for aerobic and anoxic treatment was developed. The innovative biotechnology uses sand as the media to which microorganisms attach and as the filter media for solids retention. The unique characteristics of the biosystem combine long sludge age and short hydraulic detention time and provide small footprints for the bioreactor. The novel technology has been successfully practiced for industrial and municipal wastewater treatment in three (3) continents. This article gives details of a US facility to treat coke plant effluent with high ammonia and phenol content, describes a plant in Taiwan for polishing plastic manufacturing wastewater by combining ozone and biofiltration, illustrates nitrogen removal from a semiconductor factory in Korea, and shows the results of a municipal treatment plant in Britain using BAF to pretreat peak loads from the dairy industry.