| 摘要 |
PROBLEM TO BE SOLVED: To provide a membrane separation apparatus the filtration performance of which is recovered surely and satisfactorily by cleaning a separation membrane used for filtering organic matter-containing water and to provide a membrane separation method. SOLUTION: When a membrane module 3 is cleaned by a liquid chemical, a pump 2 is stopped, valves 2a, 4a are closed, a valve 7 is open, a pump 9 is operated, a valve 11 or 15 is open and a pump 12 or 16 is operated. As a result, the filtrate and acid or alkali in a filtrate tank 5 are supplied to the secondary side 3b of the membrane module 3 through a pipeline 4, infiltrated into the separation membrane in the opposite direction and discharged from a pipeline 10 as waste backwashing water. A concentration sensor 13 of organic matter is arranged in a raw water tank 1 and the value detected by the concentration sensor is input to a controller 14. When the membrane module is cleaned by the liquid chemical, the concentration of the liquid chemical and/or a cleaning frequency of the membrane module by the liquid chemical are controlled according to the concentration of organic matter in the water to be treated. COPYRIGHT: (C)2007,JPO&INPIT
|
