Patent ID: 6939719

Claim:
An apparatus for measuring local streaming potential of a membrane for monitoring the progress of membrane fouling in the course of filtration of a hollow-fiber membrane, wherein said apparatus comprises a feed tank to reserve feed solution in a state of colloidal suspension; a delivery pump to deliver said feed solution through a feed line; a membrane module with a plurality of hollow-fibers through which said feed solution is introduced from said feed line and released through an exit line; at least one electrode installed externally of a hollow-fiber located at the inlet of the membrane module; at least one electrode installed inside the hollow-fiber located at the inlet of the membrane module; at least one electrode installed externally of a hollow-fiber located at the outlet of the membrane module; at least one electrode installed inside the hollow-fiber located at the outlet of the membrane module; a means to measure physical properties of said feed solution being introduced into a membrane module; a pressure meter that measures the transmembrane pressure difference both at the inlet and outlet of a membrane module; a flow-control valve in said exit line used to adjust the transmembrane pressure difference; a means to display and record data obtained from the above-mentioned measuring devices; and a means to calculate the value of zeta potential (ζ) of a hollow-fiber membrane.