PAC Addition for MBR Start up in Micro-polluted Water Treatment

In order to improve membrane reactor （MBR） performance for micro-polluted surface water treatment in start-up phase, removals of nitrogen and organlc matters especially synthetic organic matters by MBR and a simultaneous application of powdered activated carbon （PAC） with MBR （PAC-MBR） using flat sheet inembrane are investigated. The results confirm that MBR treatment can be effective for the removal of organic matters including trace organics. The added PAC can improve contaminant removal efficiency especially in the beginning of operation when MBR cannot effectively remove contaminants and effluent satisfying quality standards is obtained. Moreover, the removal efficiency of target trace synthetic organics is investigated and the removal mechanism is discussed. Biodegradation by microorganism, rejection by filtration of membrane with biofilm and adsorption all contribute to the removal performance. Furthermore, volatile organic compounds can be removed by aeration. The filtration process is confirmed important for natural organic matters （NOM） removal in both MBR and PAC-MBR systems. Combining with PAC, the MBR can remove all fractions of NOM while the single MBR can hardly reduce fulvic or humic acid in water even during the steady operation.