MEMBRANE FILTERING METHOD AND MEMBRANE FILTERING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a membrane filtering method of high energy efficiency in the membrane filtering method for removing impurities contained in treated water by making the water penetrate through a membrane. SOLUTION: In the case that a filtering pressure is low (in the case of YES in S03), the water to be treated is filtered while elevating the filtering pressure on the basis of the filtering speed (S09). When the filtering pressure becomes higher (NO in S03), the water to be treated is filtered while reducing the filtering speed on the basis of the filtering pressure (S05). Then, when the filtering flow rate becomes lower than a set flow rate (YES in S04), the membrane surface is washed (S08).