Modular electrochemical systems and methods

• US 9,187,350 B2
• Filed: 11/11/2011
• Issued: 11/17/2015
• 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, Yeo, Keng Hoo, Salvo, Lawrence J.
• Primary Examiner(s): Mendez, Zulmariam
• Application Number:
  US13/294,231
• Publication Number:
  US 20120118729A1
• Time in Patent Office: 1,467 Days
• Field of Search: 204/242, 204/267, 204/627
• 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 electrochemical separation system may be modular and may include at least a first modular unit and a second modular unit. Each modular unit may include a cell stack and a frame. The frame may include a manifold system. A flow distribution system in the frame may enhance current efficiency. Spacers positioned between modular units may also enhance current efficiency of the system.

Claims

1. An electrochemical separation system, comprising:

a first electrode;

a second electrode;

a first electrochemical separation modular unit having a first cell stack defining a plurality of alternating depleting compartments and concentrating compartments supported by a first frame, each of the depleting compartments comprising ion exchange membranes constructed and arranged to provide a fluid flow in a first direction, and each of the concentrating compartments comprising ion exchange membranes constructed and arranged to provide a fluid flow in a second direction that is different from the first direction, wherein each of the alternating depleting compartments and concentrating compartments is constructed and arranged to provide a fluid contact of greater than 85% of the surface area of the ion exchange membranes of each of the alternating ion diluting compartments and ion concentrating compartments, the first electrochemical separation modular unit positioned between the first electrode and the second electrode;

a second electrochemical separation modular unit, adjacent to and in cooperation with the first electrochemical separation modular unit, having a second cell stack defining a plurality of alternating depleting compartments and concentrating compartments supported by a second frame, the second electrochemical separation modular unit positioned between the first electrochemical separation modular unit and the second electrode; and

at least one blocking spacer or blocking membrane constructed and arranged to promote multi-pass flow through the plurality of depleting compartments in the system and to redirect a fluid flow through at least one of the first cell stack and the second cell stack.

2. The system of claim 1, wherein the first cell stack is surrounded by the first frame, and wherein the second cell stack is surrounded by the second frame.

3. The system of claim 1, wherein the first and second electrochemical separation modular units are arranged in parallel.

4. The system of claim 1, wherein the first and second electrochemical separation modular units are each of unitary construction.

5. The system of claim 1, wherein the first and second electrochemical separation modular units are removable.

6. The system of claim 1, wherein the first and second frames each includes a manifold system.

7. The system of claim 6, wherein the first and second frames each includes a flow distribution system.

8. The system of claim 1, wherein the first and second electrochemical separation modular units are mounted in a vessel.

9. The system of claim 8, wherein the first and second electrochemical separation modular units are mounted with a bracket assembly in the vessel.

10. The system of claim 8, further comprising a source of water to be treated fluidly connected to an inlet of the vessel.

11. The system of claim 10, wherein the depleting compartments and concentrating compartments each has an inlet in fluid communication with the inlet of the vessel.

12. The system of claim 1, wherein at least one of the depleting compartments and concentrating compartments comprises a flow redistributor.

13. The system of claim 1, wherein the system is configured such that a direction of flow through the depleting compartments is different than a direction of flow through the concentrating compartments.

14. The system of claim 13, wherein the system is configured such that the direction of flow through the depleting compartment is substantially perpendicular to the direction of flow through the concentrating compartments.

18. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned between the first and second electrochemical separation modular units.

19. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned between the first cell stack and the second cell stack.

20. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned within the first electrochemical separation modular unit.

21. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned within the first cell stack.

22. The system of claim 6, wherein the at least one blocking spacer or blocking membrane is configured to direct fluid flow from the manifold systems to the plurality of depleting compartments.

23. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned and configured to direct fluid flow through the plurality of depleting compartments in a second direction opposite to a first direction of fluid flow through the plurality of depleting compartments.

24. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned and configured to direct fluid flow through the plurality of depleting compartments in a serpentine configuration.

25. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is positioned and configured to promote current efficiency in the system.

26. The system of claim 1, wherein the at least one blocking spacer defines substantially no apertures.

27. The system of claim 1, wherein the at least one blocking spacer or blocking membrane is substantially non-conductive and is configured to promote current flow through the first cell stack.

15. A method of assembling a separation system, comprising:

mounting a first electrochemical separation modular unit having a first cell stack defining a plurality of alternating depleting compartments and concentrating compartments surrounded by a first frame in a vessel between a first electrode and a second electrode, each of the depleting compartments comprising ion exchange membranes constructed and arranged to provide a fluid flow in a first direction, each of the concentrating compartments comprising ion exchange membranes constructed and arranged to provide a fluid flow in a second direction that is different from the first direction, wherein each of the alternating depleting compartments and concentrating compartments constructed and arranged to provide a fluid contact of greater than 85% of the surface area of the ion exchange membranes of each of the alternating ion diluting compartments and ion concentrating compartments;

mounting a second electrochemical separation modular unit having a second cell stack defining a plurality of alternating depleting compartments and concentrating compartments surrounded by a second frame in the vessel between the first electrochemical separation modular unit and the second electrode; and

disposing a blocking spacer or a blocking membrane between the first and second electrochemical separation modular units, wherein the blocking spacer or the blocking membrane is constructed and arranged to promote multi-pass flow through the plurality of depleting compartments in the separation system and to redirect a fluid flow through at least one of the first cell stack and the second cell stack.

16. The method of claim 15, further comprising testing performance of each of the first and second electrochemical separation modular units prior to mounting in the vessel.

17. The method of claim 15, further comprising fluidly connecting a source of water to be treated to an inlet of the vessel.