Fluoride removal from brackish water by electrodialysis

Studies have been conducted to reduce fluorine by electrodialysis from a brackish water containing 3000 ppm of total dissolved solids (TDS) and 3 ppm of fluoride. Two methods have been proposed and described to minimize the precipitation risks of the bivalent salts in the concentrate compartment. Measurements indicate that after electrodialysis, the targets concerning the quality of produced water were all achieved. The method without chemical pretreatment seems more simple to conduct and more adapted to environmental requirements than the method with pretreatment. From these studies it is demonstrated that electrodialysis is a reasonable process for removing fluoride from brackish water.