PURPOSE: To prevent the clogging of a membrane to obtain a prescribed infiltration flow rate by installing a counter electrode on the side facing a porous conducting membrane of a vessel so that it may come into contact with an original liquid, connecting a voltage source between the counter electrode and the porous conducting membrane to make the counter electrode a cathode and a to make the porous conducting membrane an anode and performing filtration while impressing weak voltage between both the electrodes.
CONSTITUTION: A filter is provided with a vessel 1 having an original liquid inflow part 6 and a concentrate outflow port 7, and membrane units 2 each having a porous conducting membrane 9 installed inside the vessel 1 and having in filtrate outflow port 8. A counter electrode 3 is arranged on the opposite side to the porous conducting membrane 9 so that it may come into contact with an original liquid. A voltage source 5 connects the counter electrode 3 and the porous conducting membrane 9, and also the counter electrode 3 is made as a cathode and the porous conducting membrane 9 as an anode to perform filtration while impressing weak voltage between both the electrodes. As a result, since a gel layer an a solid layer are formed on the counter electrode, little clogging of the membrane occurs and prescribed flux is obtained. Since clogging of the membrane is little, the pressure of inflow water is lowered to save power.
MIYASAKA KUNIO
SONOMOTO KAZUHIKO
NAKAMURA HIDEKI
