Patent ID: 7704393

Claim:
A hollow fiber membrane module comprising: a plurality of bundles of hollow fiber membranes for water treatment resulting from a pressure difference, each hollow fiber membrane having a top ends end, and wherein a coating film based on a water-insoluble material is coated on the outer circumference of the hollow fiber membranes; a collector fixing bottom ends of the bundles of hollow fiber membranes; a housing placed over the collector with a predetermined gap therebetween and surrounding the bundles of hollow fiber membranes, the housing having a waste water inlet hole at a bottom end facing the collector, wherein a top end of the waste water inlet hole is placed at a plane higher than the top end of the coating film; dividers provided inside the housing and positioned between the bundles of hollow fiber membranes to partition the bundles of hollow fiber membranes; a treated-water tube installed at a center of the bundles of hollow fiber membranes and extended inside the collector, the treated-water tube having a bottom treated-water inlet hole communicating with inner passages of the hollow fiber membranes and a top treated-water outlet hole to exhaust treated-water; an air tube externally surrounding the treated-water tube with a predetermined gap therebetween and having a top air inlet hole to receive air and a bottom air outlet hole to exhaust air, with the bottom air outlet hole placed over the collector; and a diffuser placed between the collector and the waste water inlet hole and surrounding the bottom air outlet hole and the bundles of hollow fiber membranes, the diffuser receiving air from the bottom air outlet hole and diffusing air bubbles to all the bundles of hollow fiber membranes partitioned by the dividers.