Patent ID: 7531091

Claim:
A membrane filter for submerged operation comprising: (a) a frame that can be lower into a liquid to be purified; (b) a plurality of modules disposed next to one another in a row, each module having a foot element attached to the frame, a permeate collection space, a plurality of tubes for a fluid connected to each end of the foot element, and a plurality of hollow fiber membrane bundles cast into the foot element, the hollow fiber membranes in each hollow fiber membrane bundle having an open end in the collection space and being closed off at their other end and terminating inside the liquid to be purified without being clamped in so as to be freely movable, the tubes being oriented vertically and connected with a collection line at the top, and (c) a pluraility of fiber holding devices attached to the tubes for lateral guidance of the hollow fiber membrances, the fiber holding devices comprising U-shaped brackets having a crosspiece and end-side shanks attachable to the tubes, the U-shaped bracket surrounding the hollow fiber membrances of a module on one side in the longitudinal direction and at the ends in front of the tubes due to their shank length being adapted to the face width of the modules, the crosspiece having projections and a profile with depressions, the projections forming compartments that are open on the side that lies opposite the crosspiece and that project into the depressions of the brackets of an adjacent module.