Cleaning Process Selection and Mechanism of Membrane Pollution in the Membrane Bioreactor

Membrane pollution and its cleaning technology in MBR water treatment process were tested. Membrane of short-term(22d) experiment and membrane of long-term(210d) experiment were cleaned separately by cold water -> hot water -> sodium hypochlorite -> ethanol, membrane fluxes came back to the 94.4% and 70.3% of the new membranes, respectively. Another membrane of long-term(210d) experiment was cleaned with different process by cold water -> hot water -> sodium hypochlorite -> sulfuric acid, membrane flux came back to the 61.4% of the new membrane. The cleaning test of membrane module showed: different cleaning process might bring different cleaning effect. Membrane pollution can be divided into biological pollution, organic pollution and inorganic pollution. They often occur simultaneously, and one kind of pollution can exacerbate another.