Effect of sludge concentration on operational characteristics of membrane bioreactor

Sludge concentration in a bio reactor is one of the important parameters for MBR. It influences not only the removal efficiencies of pollutants but also the flux of membrane module. This paper studied the increasing rule of sludge concentration during MBR treating domestic sewage. The result showed that MLVSS and MLSS both increased with time at the initial stages, but after 30 days the value of MLVSS was kept at about 6 200 mg/L,whereas MLSS continues to increase. The ratio of MLVSS/MLSS was decreased gradually from 85% to 63%.The paper simultaneity examined the treatment effects of COD?NH 3 N, TN under different mixed liquor suspended solids and drew the conclusions: the increasing of MLSS is in the favor of improving the removal efficiencies of COD and NH 3 N in a certain range. Finally, the relationship between the flow of membrane and the MLSS concentration was studied and the result is that they are linear minus correlation.