Research on the Biomass and the Backwash Sludge of Biofilter

Biomass change and removal efficiencies of suspended solids (SS) along the process in the filter were investigated. As the normal operation of the biofilter process was often influenced by the blockage, the SS and the particle size of the backwash sludge along the process were also analysed, in order to find at which position the filter is easily blocked and what causes the blockage. The results showed that the bottom of upward flow biofilter had a higher removal efficiency of SS, with the removal rate of over 70%. The biomass and the height of the filter had an obvious regularity and the biomass increased as height of the filter increased, but the biomass at the lower middle of the filter decreased with the increasing height of the filter. At the same time, the SS and the particle size of the backwash sludge along the process in the filter also indicated the similar results.