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Electric fields, membrane cleaning

In the practical application of electrodialysis there are two main process operation modes. The first one is referred to as the unidirectional electrodialysis and the second as electrodialysis reversal [22]. In a unidirectional operated electrodialysis system the electric field is permanently applied in one direction and the diluate and concentrate cells are also permanently fixed over the period of operation. Unidirectional operated electrodialysis plants are rather sensitive to membrane fouling and scaling and often require a substantial feed-solution pretreatment and stack-cleaning procedures in the form of periodical rinsing of the stack with acid or detergent solutions. The unidirectional operating concept is mainly used today for applications in the... [Pg.100]

Electric fields have been used to clean membranes and to try to prevent the depo on of charged particles onto a membrane surfiice by means of electrophoresis [Bowen Sabani, 1992 Wakeman and Tarleton, 1987]. Tubular metal ndcrofiltnitian membranes are particularly suited for this application a thin metal counter-electrode positioned centrally provides acceptable current distribution. A DC elecbic field is applied to provide a current d sity of 100-200 mA cmT near to the membrane sur ce. Use of a DC field creates gas bubbles at the membrane sui ce that leads to removal of the attached particles [Fairey Microfiltrex, undated]. The membrane is the cathode to prevent oxidation at the membrane sur ce causing chemical attack of the metal. [Pg.391]

Combined ultrasonic and electric fields have been investigated, and a synergistic membrane cleaning effect has reported [Wakeman and Tarleton, 1991]. [Pg.391]


See other pages where Electric fields, membrane cleaning is mentioned: [Pg.377]    [Pg.464]    [Pg.124]    [Pg.660]    [Pg.54]    [Pg.456]    [Pg.2043]    [Pg.1801]    [Pg.40]    [Pg.306]    [Pg.2047]    [Pg.308]    [Pg.405]   
See also in sourсe #XX -- [ Pg.391 ]




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Membrane cleaning

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