Effects of pulsed electric fields on membrane fouling in electrodialysis of NaCl solution containing humate

Fouling of ion exchange membranes is one of the major problems during electrodialysis (ED) operation. Effects of pulsed electric fields on membrane fouling in electrodialysis were studied with NaCl solution containing humate. The performances were evaluated using various frequencies of electric pulses. In desalting of NaCl solution with humate as a foulant, the optimum frequency was found to be 100 Hz in terms of conductivity and cell resistance changes. A membrane fouling index for electrodialysis (EDMFI) is proposed as a quantitative measure of the membrane fouling tendency of electrodialysis processes. (C) 2002 Elsevier Science BY. All rights reserved.