Abstract
A practical-scale DHS (Down-flow Hanging Sponge) reactor applied for treatment of the effluent from UASB reactor treating municipal sewage, was converted from 2nd generation (curtain-type sponge media) into 3rd generation (random-packing type sponge media). The process performance of the 3rd generation DHS was evaluated by conducting on-site experiment in India over one year. The DHS reactor exhibited an excellent performance in removal of organic matter and nitrogen at a relatively short HRT of only 0.66 h. Distribution of heterotrophic and autotrophic bacteria along DHS longitudinal was clarified by determining oxygen utilization activity of retained sludge on various different substrates.
