Method for preventing the fouling of the active surface of a membrane, said membrane being placed in particular in a module for the purification of waste water

摘要

The treatment of active surface of a filter membrane inserted in a fluid medium from a surface layer forming deposits, comprises arranging a plate or tubular filter membrane in a filter membrane module for sewage clarification. A ball-, tube- or cube shaped plastic form body as abrasion body is moved past in operating state of the filter membrane on the active surface into a direct nitrogen gas-/liquid stream in a forced manner and is in contact with the active surface of the filter membrane. The treatment of active surface of a filter membrane inserted in a fluid medium from a surface layer forming deposits, comprises arranging a plate or tubular filter membrane in a filter membrane module for sewage clarification. A ball-, tube- or cube shaped plastic form body as abrasion body is moved past in operating state of the filter membrane on the active surface into a direct nitrogen gas-/liquid stream in a forced manner and is in contact with the active surface of the filter membrane. Inhibiting surface layer is removed or the formation of the surface layer is prevented by an already available active surface and filtration. The pores of the filter membrane are put or held in the fluid medium in freely manner. A polymer- or ceramic based filter membrane or sintered metal- or porous glass filter membrane is used as a filter membrane. The form body is introduced between two filter membrane plates, which are arranged parallel to one another. The form body has biocidal property and maximum diagonal area of 0.5-2 cm. The surface of the form body is 1.5 times larger than the outside area of the smooth form body. The biological level (2) of a clarification tank, the wastewater in the preclarification or the wastewater supplied from the preclarification or industrial wastewater is used as fluid medium for the clarification of municipal and/or industrial wastewater. The pore diameter of the filter membrane is 500-800 nm. The filter membrane is introduced with a coating, which shows a separating layer that partially contains nanoparticles. An interval is arranged between the filter membrane plates and corresponds to the 3 fold of maximum diagonal area of the form body. The form body is introduced by a guiding device or by a flow cylinder caused by direct gas entry. A guide plate is moved past at the active surface of the filter membrane or directly introduced on the surface of the membrane.