Continuous-stirring of a Granular Sludge Immersed Membrane Bioreactor for Treating Food Wastewater

Liyu Peng, Zhihong Ma, Baoning Zhu, Haijia Su

To reduce the membrane fouling in an immersed membrane bioreactor (MBR) during the treatment of food wastewater, an additional continuous stirring was introduced. The results showed that both a better membrane performance and a higher degradation efficiency for food wastewater were obtained. The membrane contributed mostly in concentrating the activated sludge. The bioreactor ensured the degradation of the organic matter. The resistance caused by concentration polarization decreased under continuous–stirring, and the membrane flux reached 14.68 L/h*m², which was 3 times the membrane flux under non-stirring condition. The COD removal and the ammonia nitrogen removal reached 93% and 90%, respectively.