Electrodeionization (EDI) is the standard method of generating high purity water bypolishing reverse osmosis permeate. The technology utilizes electrical current toremove ionic impurities while continuously regenerating cation and anion exchange resins.
EDI is utilized in all industries that require higher purity water than RO alone can produce including power, pharmaceutical, electronics, laboratories, automotive manufacturing, bottled water and many other industrial applications. There are several commercially available products with identical principles of operation, but differing designs, materials, costs and applications. This paper will review the principles of operation electrodeionization and compare the various commercially available technologies including Ionpure, GE E-Cell, Dow, Qua and Electropure