Abstract
The fixed bed submerged filtration is known to take long time to form biofilm on the support media. Purpose of present study is to improve this problem by introducing a quick biofilm forming method described as follows. Activated sludge supplemented with ferromagnetic powder (magnetic activated sludge) was attracted on sheets of plastic magnet support media by magnetic force to form biofilm.
The method reduced time needed only several minutes for the formation of biofilm. Forty three g·m-2 biomass were attracted on the magnet support media by immersing into suspension of magnetic activated sludge. This biofilm was found to remove 80-85% COD from the synthetic waste water (a COD loading of 5.5 g·m-2d-1). The biofilm was not detached from the support media during the experimental period.
The synthetic wastewater was treated sufficiently from the the start-up without increase of biomass in the biofilm. These results suggest that this method is more efficient than usual method.
