Development of a computer simulation program of batch ion-exchange membrane electrodialysis for saline water desalination

A computer simulation program of batch ion-exchange membrane electrodialysis is developed for saline water desalination. For proceeding with the computation, the relationships between the salt concentration in desalting cells, cell voltage and the five electrodialysis parameters are expressed by the equations using the continuous electrodialysis program. A salt solution is supplied to the batch electrodialysis process, and the performance changes with time are computed with an instantaneous open/shut feed operation of a solution taking salt concentration and cell voltage as parameters. A salt solution is supplied to a one-stage and a two-stage batch electrodialysis process and the performance of drinking water production is calculated. From cell pair number and energy consumption, the multi-stage operation is economically disadvantageous compared to the single-stage operation. Limiting current density of an electrodialyzer is expressed by the function including temperature and computed.