Ultrafiltration and electrodialysis method and apparatus

Abstract From the Canadian patent

A combination electrodialysis method and apparatus comprising ultrafiltration membrane cell pairs interposed between a cation-selective membrane and an ion-nonselective membrane. The solution to be treated is fed to one side of the ultrafiltration membrane cell, a concentrating solution is delivered between the cation-selective and ion-nonselective membranes, and an electric field is applied across the assembly. Cations pass through the ion-selective membranes ions of, both polarities and weakly ionized substances pass through the ultrafiltration membrane which rejects the larger sized particles and molecules and anions pass through the ionselective membrane to maintain electrical balance.