METHOD FOR CONTROLLING INJECTION OF FLOCCULANT IN MEMBRANE FILTRATION

摘要

PROBLEM TO BE SOLVED: To provide a method for controlling the injection amount of a flocculant in membrane filtration by which a membrane filtration operation can be performed stably regardless of whether the turbidity of raw water is low or high and the stable quality of the membrane-filtered water can be secured. SOLUTION: The injection amount of the flocculant is controlled according to the value of the chromaticity/turbidity ratio of raw water that is obtained by measuring the turbidity and the chromaticity of the raw water to be membrane-filtered and calculating the value. It is particularly preferable to control the injection amount of the flocculant in proportion to the value of the apparent chromaticity/turbidity ratio of the raw water.