materials and methods
2.1 laboratory scale MBR system
A laboratory scale MBR system was used in this study.
Detailed description of this MBR system is available elsewhere(Tadkaew et al.,2010). The system consisted of a glass reactor,a continous mixer, to air pumps, a pressure sensor, and influent an effluent pumps.Two ZeeWeed-1 (ZW-1) submerged hollow fiber ultrafiltration membrane modules supplied by Zenon Environmental (Ontario, Canada) were used in this set-up.