Electrodialysis is a membrane separation technology, it is under the action of direct current electric field, with the potential difference as the driving force, using the selective permeability of ion exchange membrane, to separate electrolyte ions from the solution, so as to achieve the purpose of desalination, concentration, refining or purification of the solution. In the field of water treatment, the technology was first used for desalination of brackish water, then gradually expanded to seawater desalination, drinking water and industrial pure water treatment.

At present, electrodialysis device is widely used in desalination and desalination of water, concentration of seawater to make salt and refine dairy products.The deacidification and purification of fruit juice and the production of chemical products can also be used for the pretreatment of pure water produced in food, light industry and other industries, as well as high pure water produced in electronics and medicine industries. The primary softening and desalination of boiler feed water desalinates brackish water into drinking water.