Study On Treatment Of Domestic Wastewater By Membrane Bioreactor & Sequencing Membrane Bioreactor

In this thesis, wastewater treatment by membrane bioreactor and sequencing membrane bioreactor was investigated. The results are as follows.A membrane bioreactor was applied to treat domestic wastewater. Pollutant was removed by high concentration sludge and the rejection of hollow fiber membrane in the reactor. The pollutant removal performance was investigated at different aeration fluxes and HRTs. The results showed that excellent pollutant removal could be obtained when HRT was 13.3h, the ratio of air and waste wastewater was 58:1. When HRT was 8h, the ratio of air and wastewater was 55:1, nitrification was carried out and the removal efficient of dissolved phosphate was low.Hollow fiber membrane had rejection with COD but had no rejection with NH3-N.During this experiment, the membrane flux decreased. Washing by air to reduce the decreasing of membrane flux.A sequencing membrane bioreactor was also applied to treat domestic wastewater. Pollutant was removed by suspended sludge and bio-film in the reactor and the pollutant removal performance was investigated at different ratios of air and wastewater. The results showed that when HRT was 6h, SRT was 53d, the ratio of air and wastewater was 20:1, the removal efficiencies of COD and NH3-N were high. The removal efficient of dissolved phosphate was low. Dynamic kinetics on the reaction of COD and NH3-N was also investigated.