Patent ID: 6248226
Filing Date: 2001-06-19
Classification: B01D,B01J,C02F

Abstract:
A process for producing deionized water by eletrodeionization wherein an anion exchange material and a cation exchange material are filled between cation exchange membranes and anion exchange membranes to form ion depletion compartments, concentration compartments are provided on both sides of said ion depletion compartments with said cation exchange membranes or said anion exchange membranes therebetween, and said ion depletion compartments and said concentration compartments are disposed between an anode and a cathode, and wherein feed water is flowed into said ion depletion compartments with application of a voltage while flowing concentrating water into said concentration compartments to remove impurity ions in feed water for production of deionized water; wherein the feed water and the concentrating water are flowed into said ion depletion compartments and said concentration compartments, respectively, in such a way that the direction of flow of feed water being fed into said ion depletion compartments is opposite to the direction of flow of concentrating water being fed into said concentration compartments, and wherein the feed water flowed into said ion depletion compartments is first passed through respective anion exchange material layers.