ABSTRACTElectrodialysis is a unit operation which removes ionic species from a solution through the use of an imposed voltage and ion‐selective membranes. The temperature, flow rate, and composition of the feed, and the applied voltage all influence the rate of ionic transport in electrodialysis systems. The effects of the aforementioned process parameters on the performance of an electrodialysis system were investigated using cottage cheese whey as the process feed. Increasing the flow rate proved to be of little value in decreasing the membrane stack resistance for a given run, but it significantly retarded the rate at which the stack resistance increased in repeated runs. The effect of increasing the total solids concentration of the whey without altering the solute composition was to increase the potential rate of demineralization through an increase in conductivity. Prefractionation of the feed by ultrafiltration enhanced the value of the whey solids by increasing the protein concentration and decreasing the ash concentration. However, the electrodialytic process was less efficient in removing the remaining ash in this case than it was in demineralizing other feed
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