Cleaning techniques of dynamic membranes

The feasibility of cleaning dynamic membranes without causing deleterious effects to their performance was investigated. The primary membrane used throughout the investigation was made of multifilament woven polyester, while the dynamic membrane was formed from a precipitate of manganese dioxide (MnO2). Acid cleaning, cleaning with lap water, air scouring and an off-on mechanism were investigated as cleaning mechanisms with dynamic membranes. The investigation showed the difficulty of keeping dynamic membranes intact without altering their performance. This was attributed to switching off the circulation pump of the experimental set-up, which caused some parts of the dynamic membrane to be dislodged. The study suggests complete removal of the dynamic membrane and cleaning the primary membrane to its initial conditions. This was achieved easily and efficiently by brushing the outside surface of the woven polyester primary membrane. (C) 1997 Elsevier Science B.V.