Method of providing a source of potable water

• US 9,138,689 B2
• Filed: 11/11/2011
• Issued: 09/22/2015
• Est. Priority Date: 11/12/2010
• Status: Active Grant

• Current Assignee: Evoqua Water Technologies LLC
• Original Assignee: Evoqua Water Technologies LLC
• Inventors: Liang, Li-Shiang, Gifford, Joseph D., Chan, John K., Salvo, Lawrence J.
• Primary Examiner(s): Hendricks, Keith
• Assistant Examiner(s): Jain, Salil
• Application Number:
  US13/294,266
• Publication Number:
  US 20120118738A1
• Time in Patent Office: 1,411 Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2315/10 Cross-flow filtration
• CPC Class Codes: B01D 61/463 comprising the membrane sequence AC or CA, where C is a cation exchange membrane
• CPC Class Codes: B01D 61/48 having one or more compartments filled with ion-exchange material , e.g. electrodeionisation
• CPC Class Codes: B01D 61/50 Stacks of the plate-and-frame type
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: C02F 1/4693 electrodialysis
• CPC Class Codes: C02F 1/4695 electrodeionisation
• CPC Class Codes: C02F 2201/46 Apparatus for electrochemical processes
• CPC Class Codes: C25B 9/00 Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
• CPC Class Codes: C25B 9/19 with diaphragms
• CPC Class Codes: C25B 9/70 Assemblies comprising two or more cells
• CPC Class Codes: H01F 41/02 for manufacturing cores, coils, or magnets H01F41/14 takes precedence; for dynamo-electric machines H02K15/00
• CPC Class Codes: Y02A 20/124 Water desalination
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor

Abstract

An electrical purification apparatus and methods of making same are disclosed. The electrical purification apparatus may provide for increases in operation efficiencies, for example, with respect to current efficiencies and membrane utilization.

Claims

1. A method of providing a source of potable water, comprising:

providing an electrical purification apparatus, comprising;

a cell stack comprising alternating ion diluting compartments and ion concentrating compartments, each of the ion diluting compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a first direction, and each of the ion concentrating compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a second direction that is different from the first direction;

a housing enclosing the cell stack;

a blocking spacer comprising a screen portion positioned in at least one of the alternating ion diluting compartments and ion concentrating compartments and a solid portion positioned outside of the at least one of the alternating ion depleting compartments and the ion concentrating compartments, the solid portion of the blocking spacer having an edge in contact with the housing

a frame positioned between the housing and the cell stack to provide a first modular unit, the frame constructed and arranged to provide the fluid flows in the first and second directions and to provide a current bypass path having an electrical resistance sufficient to promote current flow through the cell stack;

fluidly connecting a seawater feed stream comprising about 35,000 ppm total dissolved solids to an inlet of the electrical purification apparatus; and

fluidly connecting an outlet of the electrical purification apparatus to a potable point of use.

2. The method of claim 1, wherein the electrical purification apparatus further comprises a second modular unit secured within the housing.

3. The method of claim 2, wherein the electrical purification apparatus is configured to promote multi-pass flow within the electrical purification apparatus.

4. The method of claim 2, wherein the electrical purification apparatus further comprises a blocking spacer positioned between the first modular unit and the second modular unit.

5. The method of claim 1, wherein the electrical purification apparatus further comprises a bracket assembly positioned between the frame and the housing.

6. The method of claim 1, wherein the first direction of fluid flow is perpendicular to the second direction.

7. The method of claim 1, wherein the electrical purification apparatus further comprises a baffle structure within at least one of the alternating ion diluting compartments and ion concentrating compartments.

8. The method of claim 1, wherein at least one of the alternating ion diluting compartments and ion concentrating compartments is constructed and arranged to provide flow distribution within the compartment.

9. The method of claim 1, further comprising passing the seawater feed stream through multiple stages in the electrical purification apparatus to provide the source of potable water.

10. The method of claim 1, wherein the fluid flow in the first direction is a direct fluid flow in the first direction, and the fluid flow in the second direction is a direct fluid flow in the second direction.

11. The method of claim 1, wherein the ion exchange membranes of each of the alternating ion diluting compartments and ion concentrating compartments are secured at a portion of a periphery of the ion exchange membranes.

12. The method of claim 11, wherein the fluid flow in the first direction is a direct fluid flow in the first direction, and the fluid flow in the second direction is a direct fluid flow in the second direction.

14. The electrical purification apparatus of claim 1, wherein the frame is constructed and arranged to provide a current efficiency of at least about 85%.

15. The electrical purification apparatus of claim 1, wherein the frame is constructed and arranged such that the current bypass path has a higher resistance than that of a direct path through the cell stack.

13. A method of facilitating production of potable water from brackish water or seawater, comprising:

providing an electrical purification apparatus, comprising;

a cell stack comprising alternating ion diluting compartments and ion concentrating compartments, each of the ion diluting compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a first direction, and each of the ion concentrating compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a second direction that is different from the first direction;

a housing enclosing the cell stack;

a blocking spacer comprising a screen portion positioned in at least one of the alternating ion diluting compartments and ion concentrating compartments and a solid portion positioned outside of the at least one of the alternating ion depleting compartments and the ion concentrating compartments, the solid portion of the blocking spacer having an edge in contact with the housing; and

a frame positioned between the housing and the cell stack to provide a first modular unit, the frame constructed and arranged to provide the fluid flows in the first and second directions and to provide a current bypass path having an electrical resistance sufficient to promote current flow through the cell stack.

16. A method of providing a source of potable water, comprising:

providing an electrical purification apparatus, comprising;

a cell stack comprising alternating ion diluting compartments and ion concentrating compartments, each of the ion diluting compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a first direction, and each of the ion concentrating compartments comprising ion exchange membranes and constructed and arranged to provide a fluid flow in a second direction that is different from the first direction;

a housing enclosing the cell stack;

a blocking spacer comprising a screen portion positioned in at least one of the alternating ion diluting compartments and ion concentrating compartments and a solid portion positioned outside of the at least one of the alternating ion depleting compartments and the ion concentrating compartments, the solid portion of the blocking spacer having an edge in contact with the housing; and

a frame positioned between the housing and the cell stack to provide a first modular unit, the frame constructed and arranged to provide the fluid flows in the first and second directions and to provide a current bypass path having an electrical resistance sufficient to promote current flow through the cell stack;

fluidly connecting a brackish feed stream comprising from about 1,000 ppm to about 10,000 ppm total dissolved solids to an inlet of the electrical purification apparatus; and

fluidly connecting an outlet of the electrical purification apparatus to a potable point of use.