Optimizing the operational conditions of a membrane bioreactor used for domestic wastewater treatment

This study evaluated the performance of a sidestream membrane module combined with an aeration system for the treatment of municipal wastewater. To investigate the membrane's behavior and to control fouling, trials in laboratory units were conducted. In these tests, optimal values were established for some operational parameters, such as crossflow velocity, transmembrane pressure and air supply to continuously flush the membrane surface. Air supply improved the behavior of the permeate flux over time. After six hours operation, the stabilized flux was 35 L/m(2) h at a total pressure of 0.40 bar (wastewater pressure of 0.05 bar and airpressure of 0.35 bar) and Reynolds Number of 4,600. All permeate samples analyzed indicated absence of fecal coliform and Escherichia coli.