Patent ID: 6998044

Claim:
An apparatus for use in purifying water that contains suspended and dissolved solids, comprising: (a) a retentate chamber sized and adapted to receive a selected volume of fluid, (i) said retentate chamber including an inlet adapted to be placed in fluid communication with a source of the water that contains suspended and dissolved solids; (b) a permeate chamber adjacent the retentate chamber and sized and adapted to receive a selected volume of fluid; (c) a filter membrane interposed between the retentate chamber and the permeate chamber, (i) said filter membrane operative when said inlet is in fluid communication with the source (A) to retain in the retentate chamber a majority of the suspended solids thereby to form in the retentate chamber a retentate containing suspended solids, and (B) to pass to the permeate chamber at least some of the dissolved solids thereby to form in the permeate chamber a permeate containing dissolved solids; (d) a diluting chamber sized and adapted to receive a selected volume of said permeate, (i) said diluting chamber including a mixture of at least one cation exchange resin and at least one anion exchange resin disposed therein; (e) a first conduit interconnecting said permeate chamber and said diluting chamber and operative to establish fluid communication therebetween; (f) an outlet communicating with the diluting chamber and operative to receive deionized water therefrom; (g) a cation concentrating chamber adjacent the diluting chamber; (h) a cation-selective membrane interposed between the diluting chamber and the cation-concentrating chamber, (A) said cation-selective membrane operative to retain anions in the diluting chamber and to pass cations into the cation-concentrating chamber; (i) an anion-concentrating chamber adjacent the diluting chamber; (j) an anion-selective membrane interposed between the diluting chamber and the anion-concentrating chamber, (A) said anion-selective membrane operative to retain cations in the diluting chamber and to pass anions into the anion-concentrating chamber; (k) a second conduit communicating with at least one of the retentate chamber, cation-concentrating chamber and anion-concentrating chamber and adapted to receive the suspended and dissolved solids therefrom; (l) at least one cathode and anode operative to create an electric field across said retentate chamber, permeate chamber, diluting chamber, cation-concentrating chamber and anion-concentrating chamber; and (m) wherein said chamber are formed by a plurality of alternating membranes and spacers.