Electromembrane process with pulsed electric field

Electromembrane process yields can be enhanced by using pulsed electric field. Electrodialysis experiments carried out on brackish water solutions show that the same level of desalination can be reached faster under pulsed field conditions. A model based on the Nernst–Planck equations is developed to explain this behavior.

Current density Membrane pd t (time) Fig. 1. Time dependence for the concentration profiles in the depletion layer C(x,t). has been realized. pH and conductivities have been followed during the process. The same study has been performed with a reconstituted Tunisian brakish water to produce a fresh one (Fig. 2). In order to increase the performance of the electrodialysis process we applied a pulsed electric field with different duty cycle. We compare conductivity variation in the pulse mode with In this work we present a transport model based on the Nernst–Planck equation, which is used for the study of pulsed wave shape influence on the concentration polarization phenomenon. Optimisation of parameters (shape and duration) have been found. The results will show the improvement brought by the pulsed electric field electrodialysis: lowering of the concentration polarization phenomenon, less scaling, and sometimes fouling: lowering of the energy consumption.