Since its introduction in the 1960s, electrodialysis (ED) technology has been adopted for a wide range of industrial applications, and today it is the second-most widely used membrane desalination technology.

The traditional technology involves applying a direct-current electric field to flux positive ions across cation exchange membranes in one direction, and negative ions through anion exchange membranes in the opposite direction.

More recently, it has benefited from an innovation that helps to keep the membranes cleaner by allowing the polarity of electrodes and hydraulic channels to “reverse.”

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