Electrodialysis

Electrodialysis is a membrane separation process that uses an applied electric potential to transport dissolved salt ions across ion-exchange membranes, drawing negatively charged ions toward a positive electrode and positively charged ions toward a negative electrode, so that dissolved salts are concentrated in a separate stream rather than the water itself being removed, as happens in reverse osmosis or distillation. This makes electrodialysis particularly efficient for desalinating water with relatively low salt concentrations, such as brackish water, and the technology's major historical application has been the desalination of brackish water and seawater, especially in Japan. Electrodialysis is now also used in drinking water production, industrial wastewater treatment, food processing, and zero-liquid-discharge systems. No single clean origin date or inventor is established in the source consulted.