MEMBRANE FILTRATION MODULE CLEANING METHOD, MEMBRANE FILTRATION APPARATUS, AND CHEMICAL-USED CLEANING APPARATUS

摘要

PROBLEM TO BE SOLVED: To recover the filtration performance of a membrane filtration module to be lowered by the material fouled on the membrane filtration module. SOLUTION: The pressure of the raw water side of the membrane filtration module is reduced to be lower than the atmospheric one and then is rapidly increased to be equal to or higher than the atmospheric one. After the pressure is returned to the atmospheric one, the membrane filtration module is cleaned by elevating and lowering the level of washing water or a liquid chemical several times while scrubbing with air. At that time, the filtrate side of the membrane filtration module is filled with the air of the atmospheric pressure or higher. As a result, the fouled material can be easily peeled off and the cleaning effect can be improved by the expansion and rapid contraction of air bubbles. COPYRIGHT: (C)2003,JPO