Membrane filter cleansing process

Abstract

Immersed hollow-fiber membrane filtration systems sometimes encounter process problems as a result of solids accumulation in and around the hollow fibers. The solids can accumulate to the point where they begin to dewater and form a mud like substance known as sludge. In some embodiments of the invention there is provided a process for substantially preventing the accumulation of sludge build-up on membrane fibers and/or cleansing membrane fibers that have been fouled by a substantial sludge build-up. Many of these embodiments involve aerating a membrane tank in which the membrane fibers are immersed after the water level has been reduced to near the level of solids accumulation. In some embodiments of the invention, the energy released by bursting bubbles at the liquid-air interface is employed to prevent fouling of membrane fibers and/or cleanse fouled membrane fibers.

Dependencies are inferred from the claim text.