ELECTROCHEMICAL ION EXCHANGE TREATMENT OF FLUIDS

• US 20070108056A1
• Filed: 10/06/2006
• Published: 05/17/2007
• Est. Priority Date: 10/06/2005
• Status: Active Grant

• Current Assignee: Zhejiang Langke Membrane Materials Technology Company Limited
• Original Assignee: Pionetics Corporation
• Inventors: Nyberg, Eric, Holmes, James, Janah, Ashok, Vogdes, Christine
• Granted Patent: US 8,562,803 B2
• Time in Patent Office: Days
• US Class Current: 204/554
• CPC Class Codes: B01D 2311/24 Quality control
• CPC Class Codes: B01D 61/44 Ion-selective electrodialysis
• CPC Class Codes: B01D 61/54 Controlling or regulating
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 1/283 using coal, charred products, or inorganic mixtures containing them
• CPC Class Codes: C02F 1/32 with ultraviolet light
• CPC Class Codes: C02F 1/441 by reverse osmosis
• CPC Class Codes: C02F 1/4602 for prevention or elimination of deposits
• CPC Class Codes: C02F 1/46109 Electrodes
• CPC Class Codes: C02F 1/4672 by electrooxydation
• CPC Class Codes: C02F 1/469 by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis
• CPC Class Codes: C02F 1/4693 electrodialysis
• CPC Class Codes: C02F 1/4695 electrodeionisation
• CPC Class Codes: C02F 2001/422 using anionic exchangers
• CPC Class Codes: C02F 2001/425 using cation exchangers
• CPC Class Codes: C02F 2001/46152 characterised by the shape or form electrodes in particulate form or with conductive or non-conductive particles between them C02F1/46114
• CPC Class Codes: C02F 2201/003 Coaxial constructions, e.g. a cartridge located coaxially within another
• CPC Class Codes: C02F 2201/46115 Electrolytic cell with membranes or diaphragms
• CPC Class Codes: C02F 2201/46125 Electrical variables
• CPC Class Codes: C02F 2201/4613 Inversing polarity
• CPC Class Codes: C02F 2201/46145 : Fluid flow
• CPC Class Codes: C02F 2201/4616 : Power supply
• CPC Class Codes: C02F 2209/02 : Temperature
• CPC Class Codes: C02F 2209/03 : Pressure
• CPC Class Codes: C02F 2209/05 : Conductivity or salinity
• CPC Class Codes: C02F 2209/40 : Liquid flow rate
• CPC Class Codes: C02F 2301/026 : Spiral, helicoidal, radial
• CPC Class Codes: C02F 2301/043 : Treatment of partial or bypass streams
• CPC Class Codes: C02F 2303/04 : Disinfection
• CPC Class Codes: C02F 2303/16 : Regeneration of sorbents, filters
• CPC Class Codes: Y02A 20/124 : Water desalination
• CPC Class Codes: Y02A 20/131 : Reverse-osmosis

Abstract

A fluid treatment apparatus for treating a fluid comprises an electrochemical cell having fluid orifices to receive and release fluid, and a fluid passageway connecting the orifices with a water-splitting ion exchange membrane is exposed to the fluid in the passageway. First and second electrodes are positioned about the membrane. The apparatus also comprises a controller to control and operate a power supply and valve system. The power supply supplies a current to the first and second electrodes at sufficiently high current density to result in bacteriostasis, deactivation, or a reduction in the microorganisms in the fluid. The controller can also operate a set of cells to deionize fluid and regenerate the cells.

Claims

1. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising

(i) a plurality of fluid orifices to receive an input fluid and release an output fluid, the input fluid comprising a first level of active microorganisms;

(ii) first and second electrodes; and

(iii) an ion exchange membrane between the first and second electrodes to treat the input fluid to form the output fluid;

(b) a power supply to apply a current to the first and second electrodes; and

(c) a controller to control the power supply to apply to the first and second electrodes, a current having a current density which is sufficiently high to deactivate the microorganisms in the fluid such that the output fluid comprises a second level of active microorganisms which is less than the first level of active microorganisms in the input fluid.

2. An apparatus according to claim 1 wherein the controller controls the power supply to apply to the first and second electrodes, a current having a current density from about 0.01 to about 20 mA/cm².

3. An apparatus according to claim 1 wherein the first and second levels comprise colony forming units per 100 mL of fluid, and wherein the second level comprises fewer colony forming units per 100 mL of the output fluid than the first level of colony forming units per 100 mL of the input fluid.

4. An apparatus according to claim 3 wherein the current density is sufficiently high to substantially prevent an increase in the colony forming units per 100 mL in the output fluid.

5. An apparatus according to claim 4 wherein the controller controls the power supply to apply to the first and second electrodes, a current having a current density that is sufficiently high to provide an output fluid having a second level of colony forming units per 100 mL that is at least about 90% lower than the first level of colony forming units per 100 mL of the input fluid.

6. An apparatus according to claim 1 wherein the first and second levels of active microorganisms comprise heterotrophe bacteria plate counts.

7. An apparatus according to claim 4 wherein the input fluid comprises a first level of a microorganism comprising a heterotrophe bacteria plate count of at least about 500 Cfu/mL, and wherein the controller sets the current density sufficiently high to provide an output fluid having a heterotrophe bacteria plate count of less than about 450 Cfu/mL.

8. An apparatus according to claim 1 wherein the controller sets the current density sufficiently high to provide an output fluid having at least one log reduction of bacteria plate count for a fluid residence time of at least 0.05 minute.

9. An apparatus according to claim 1 wherein the controller sets the current density sufficiently high to provide an output fluid having at least two log reduction of bacteria plate count.

12. An apparatus according to claim 4 wherein the input fluid comprises a first level of a microorganism comprising a heterotrophe bacteria plate count of at least about 500 Cfu/mL, and wherein the controller sets the current density sufficiently high to provide an output fluid having a heterotrophe bacteria plate count of less than about 450 Cfu/mL.

10. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising

(i) a plurality of fluid orifices to receive an input fluid and release an output fluid, the input fluid comprising a first heterotrophe bacteria plate count, and the output fluid comprising a second heterotrophe bacteria plate count;

(ii) first and second electrodes; and

(iii) an ion exchange membrane between the first and second electrodes to treat the input fluid to form the output fluid, the ion exchange membrane comprising both anion and cation exchange surfaces;

(b) a power supply to apply a current to the first and second electrodes; and

(c) a controller to control the power supply to supply a current to the first and second electrodes to obtain an electric potential drop of at least about 0.05 volts/membrane and that is sufficiently high to substantially prevent an increase in the plate count of the heterotrophe bacteria in the output fluid, so that a second plate count of heterotrophe bacteria in the output fluid is lower than the first plate count of heterotrophe bacteria in the input fluid.

11. An apparatus according to claim 10 comprising applying a current to obtain an electric potential drop of less than about 20 volts/membrane.

13. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising;

(i) fluid orifices to receive input fluid and release output fluid, the input fluid having a first level of a microorganism;

(ii) a water-splitting membrane; and

(iii) first and second electrodes about the water-splitting membrane;

(b) a valve to control the flow of input fluid into a fluid orifice of the electrochemical cell;

(c) a power supply to supply a current to the first and second electrodes; and

(d) a controller to operate the valve to flow the input fluid into a fluid orifice of the electrochemical cell to provide a residence time of the fluid in the cell of at least 0.05 minutes, while controlling the power supply to supply to the first and second electrodes, a current having a current density of from about 0.01 to about 20 mA/cm², and which is sufficiently high to deactivate microorganisms in the input fluid to provide an output fluid having at least one log reduction of microorganisms for the fluid residence time of at least 0.05 minute.

14. A method of treating a fluid having a first level of active microorganisms, in an electrochemical cell comprising a water-splitting membrane between a pair of electrodes, the method comprising:

(a) exposing the fluid to the water-splitting membrane; and

(b) applying a current through the fluid via the pair of electrodes, the current having a sufficiently high current density to deactivate the microorganisms in the input fluid to form an output fluid having a second level of active microorganisms which is less than the first level of active microorganisms.

15. A method of treating an input fluid comprising a first plate count of active heterotrophe bacteria, in an electrochemical cell comprising a pair of electrodes about a water-splitting membrane comprising anion and cation exchange surfaces, and the method comprising:

(a) flowing the input fluid past both the anion and cation exchange surfaces the water-splitting membrane; and

(b) maintaining across the cation and anion exchange surfaces of the water-splitting membrane, an electric potential drop of at least about 0.05 volts/membrane and which is sufficiently high to substantially prevent an increase in the plate count of the heterotrophe bacteria in the output fluid, so that a second plate count of heterotrophe bacteria in the output fluid is less than or equal to the first plate count of heterotrophe bacteria in the input fluid.

16. A method according to claim 15 comprising maintaining an electric potential drop of at least about 20 volts/membrane.

17. A method of treating a fluid comprising active microorganisms in an electrochemical cell comprising a water-splitting membrane between a pair of electrodes, the membrane having anion and cation exchange surfaces, and the method comprising:

(a) flowing a fluid past both anion and cation exchange surfaces of the water-splitting membrane to provide a fluid residence time of at least 0.05 minutes in the electrochemical cell; and

(b) maintaining a current density of at least 0.01 mA/cm² through the cell to substantially prevent an increase of the number of active microorganisms in the fluid.

18. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having fluid orifices, a pair of electrodes, and a water-splitting membrane between the electrodes;

(b) a filter connected to a fluid orifice of the electrochemical cell;

(c) a power supply to supply a current to the electrodes of the cell;

(d) a valve to control the flow of fluid through the fluid orifices of the cell; and

(e) a controller to control the valve and power supply, wherein the controller;

(1) in a fluid deionization stage, operates the valve to flow fluid into a fluid orifice of the cell while controlling the power supply to supply a current to the electrodes to deionize the fluid to form deionized fluid that is released at another fluid orifice; and

(2) in a regeneration stage, operates the valve to provide fluid into a fluid orifice of the cell while controlling the power supply to supply a current to the electrodes to regenerate the ion exchange membrane to form regenerated waste fluid which is released at another orifice.

19. An apparatus according to claim 18 wherein the filter comprises a sediment filter.

20. An apparatus according to claim 19 wherein the sediment filter comprises a cartridge type or bag type filter.

21. An apparatus according to claim 20 wherein the cartridge type filter has a pore structure which will filter out particles having a dimension of at least 5 micron.

22. An apparatus according to claim 20 wherein the sediment filter is also an antimicrobial filter.

23. An apparatus according to claim 18 wherein the filter comprises an activated carbon filter.

24. An apparatus according to claim 18 wherein filter comprises an ion selective media filter.

25. An apparatus according to claim 18 wherein the filter comprises a reverse osmosis filtration cell.

26. An apparatus according to claim 18 further comprising an antimicrobial cell.

27. A method of filtering fluid in an electrochemical cell having a water-splitting membrane between a pair of electrodes, the method comprising:

(a) deionizing the fluid by passing the fluid through the electrochemical cell while supplying a current to the electrodes of the cell to deionize the fluid while deactivating microorganisms in the fluid;

(b) passing the fluid though an activated carbon filter;

(c) passing the fluid through a sediment filter; and

(d) exposing the fluid to ultraviolet radiation.

28. A method of treating a fluid in a fluid treatment apparatus comprising (i) an electrochemical cell comprising fluid orifices, a water-splitting membrane between a pair of electrodes, (ii) a filter connected to a fluid orifice of the electrochemical cell, (iii) a valve to control the flow of fluid through the fluid orifices of the cell, (iv) a power supply to supply a current to the electrodes;

and (v) a controller to control the power supply and valve, the method comprising;

(a) in a fluid treatment cycle,

(i) deionizing the fluid by passing the fluid into a fluid orifice of the cell while supplying a current to the electrodes of the cell to deionize the fluid; and

(ii) flowing the fluid through a reverse osmosis filter; and

(b) in a regeneration cycle, flowing fluid into a fluid orifice of the cell while supplying a current to the electrodes of the cell to regenerate the water-splitting membrane.

29. A fluid treatment apparatus for treating a fluid, the apparatus comprising:

(a) an electrochemical cell comprising

(i) fluid orifices to receive the fluid, the fluid having a first level of active microorganisms;

(ii) first and second electrodes; and

(iii) a water-splitting membrane between the first and second electrodes;

(b) a power supply to supply a current to the first and second electrodes;

(c) a controller to control the power supply to apply to the first and second electrodes, a current having a sufficiently high current density to deactivate microorganisms in the fluid in the electrochemical cell; and

(d) an antimicrobial cell comprising a source of an antimicrobial agent to expose the fluid to an antimicrobial agent.

30. An apparatus according to claim 29 in which the antimicrobial agent comprises at least one of the following:

(1) halide ions;

(2) sodium chloride;

(3) N-halamine;

(4) an oxidizer; and

(5) silver ion.

31. An apparatus according claim 29 wherein the antimicrobial cell is the electrochemical cell, and wherein the electrochemical cell comprises a source of an antibacterial agent.

32. An apparatus according to claim 29 wherein the antimicrobial agent comprises at least one of an antibacterial antiviral, antifungal, antiparasitic, immunotherapeutic, antibiotic and chemotherapeutic agent.

33. An apparatus according to claim 29 wherein the antimicrobial agent is added in a concentration that is sufficiently high to disinfect fluid at a flow rate of at least about 2 L/min.

34. An apparatus according to claim 29 wherein the antimicrobial cell comprises a drip system to add antimicrobial agent to the fluid passing through the cell.

35. An apparatus according to claim 29 in which the antimicrobial agent is incorporated in the water-splitting membrane of the electrochemical cell.

36. A method of treating a fluid to deactivate microorganisms, in an electrochemical cell comprising electrodes about a water-splitting membrane having anion and cation exchange surfaces, the method comprising:

(a) exposing the fluid to the water-splitting membrane while applying a current through the fluid, the current having a sufficiently high current density to deactivate the microorganisms in the fluid; and

(b) exposing the fluid to an antimicrobial agent.

37. A method according to claim 36 wherein (b) comprises adding antimicrobial agent into the fluid.

38. A method according to claim 36 wherein (b) comprises exposing the fluid to a membrane comprising the antimicrobial agent.

104. An apparatus according to claim 37 in which the controller sets the magnitude of the current in response to the temperature signal.

105. An apparatus according to claim 38 in which the controller changes the magnitude of the current by steps of at least about 20%.

39. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, and an ion exchange membrane between a pair of electrodes;

(b) a power supply to supply a current to the electrodes;

(c) a valve to control the flow of fluid through the orifices of the cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into an orifice of the cell while controlling the power supply to supply a current having a current density to the pair of electrodes to form deionized fluid which is released at another orifice; and

(2) in a post deionization cycle, close the valve to substantially stop the flow of fluid into the cell, while continuing to control the power supply to supply a deionization current to the electrodes for a time period.

40. An apparatus according to claim 39 wherein in the post-deionization cycle, the deionization current is applied at a current density of at least about 0.5 mA/cm², and for a time period of less than about 10 minutes.

41. An apparatus according to claim 39 wherein the time period is less than about 5 minutes.

42. An apparatus according to claim 39 wherein in the deionization cycle, the current density supplied to the electrodes is at least about 0.05 mA/cm².

43. An apparatus according to claim 39 wherein in the post-deionization cycle, the current density supplied to the electrodes is less than about 5 mA/cm².

44. A fluid treatment method conducted in an electrochemical cell, the method comprising:

(a) flowing fluid into the cell while maintaining a current in the cell to deionize the fluid;

(b) stopping the flow of fluid into the cell and allowing residual fluid to remain in the cell; and

(c) after stopping the flow of fluid into the cell, continuing to supply a deionization current through the cell for a time period.

45. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a first orifice abutting a cylindrical outer wall, a second orifice abutting a tubular inner wall, a first electrode adjacent to the cylindrical outer wall, a second electrode about the tubular inner wall, and a spiral wound ion exchange membrane between the electrodes;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the orifices of the cell; and

(d) a controller to control the power supply and valve to

(1) in a deionization cycle, flow fluid into the second orifice so that the fluid travels from the tubular inner wall to the cylindrical outer wall to be released at the first orifice, while supplying a current to the electrodes to deionize the fluid; and

(2) in a regeneration cycle, flow fluid into the first orifice so that the fluid travels from the cylindrical outer wall to the tubular inner wall to be released at the second orifice, while supplying a current to the electrodes to regenerate the spiral wrap ion exchange membrane.

46. A fluid treatment method conducted in an electrochemical cell comprising a first orifice abutting a cylindrical outer wall, a second orifice abutting a tubular inner wall, a first electrode adjacent to the cylindrical outer wall, a second electrode about the tubular inner wall, and a spiral wound ion exchange membrane between the electrodes, the method comprising:

(a) a deionization cycle comprising flowing fluid into the second orifice so that the fluid travels from the tubular inner wall to the cylindrical outer wall to be released at the first orifice, while supplying a current to the electrodes to deionize the fluid; and

(b) a regeneration cycle comprising flowing fluid into the first orifice so that the fluid travels from the cylindrical outer wall to the tubular inner wall to be released at the second orifice, while supplying a current to the electrodes to regenerate the spiral wrap ion exchange membrane.

47. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, and an ion exchange membrane between a pair of electrodes;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the orifices of the cell; and

(d) a controller to;

(1) in a fluid deionization cycle, operate the valve to pass fluid into an orifice of the cell while controlling the power supply to supply a current to the electrodes to form deionized fluid that is released at another orifice; and

(2) in a regeneration cycle, operating the valve to provide a timed burst of fluid into an orifice of the cell, the timed burst comprising opening the valve for a time period shorter than the regeneration cycle time, and then closing the valve, while controlling the power supply to supply a current to the electrodes to regenerate the ion exchange membrane to form regenerate fluid which is released at another orifice.

48. An apparatus according to claim 47 wherein in (d) (2) the controller operates the valve to provide a plurality of timed bursts of fluid in the regeneration cycle time.

49. An apparatus according to claim 47 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid for time periods of from about 0.1% to about 80% of the regeneration cycle time.

50. An apparatus according to claim 47 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid for time periods of from about 0.1 to about 40 seconds.

51. An apparatus according to claim 47 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid for different time periods during the regeneration cycle time.

52. An apparatus according to claim 51 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid (i) during a first regeneration stage for time periods of from about 0.1% to about 30% of the regeneration cycle time;

(ii) during a second regeneration stage for about 0.3% to about 80% of the regeneration cycle time; and

(iii) during a third regeneration stage for time periods of from about 0.1% to about 30% of the regeneration cycle time.

53. An apparatus according to claim 51 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid (i) during a first regeneration stage for time periods of from about 0.1 to about 10 seconds;

(ii) during a second regeneration stage for time periods of from about 3 to about 40 seconds; and

(iii) during a third regeneration stage for time periods of from about 0.1 to about 10 seconds.

54. An apparatus according to claim 47 wherein the controller operates the valve to provide timed bursts of fluid during one regeneration stage that is a least about 2 times longer than the time period during another regeneration stage.

55. An apparatus according to claim 47 wherein the controller operates the valve to provide timed bursts of fluid during a last regeneration stage having a time period that is less than about ½

the time period of a preceding or following regeneration stage.

56. An apparatus according to claim 47 wherein in (d) (2) the controller operates the valve to provide timed bursts of fluid during (i) the first regeneration stage which are performed from the commencement of the regeneration cycle until a time of less than about 2 minutes later, (ii) the second regeneration stage is performed for a time of at least about 3 minutes further, and (iii) the third regeneration stage performed for at least about 3 minutes further.

57. An apparatus according to claim 47 further comprising a flow sensor that measures a flow rate through the first cell and sends a flow signal to the controller to operate the valve to set the duration of the timed bursts of fluid.

58. An apparatus according to claim 47 further comprising a second electrochemical cell comprising a housing having a plurality of orifices, a pair of electrodes, and an ion exchange membrane between the electrodes, and

wherein the controller controls the power supply and valve to deionize fluid in the second cell in a deionization cycle and pass the deionized fluid to the orifice of the first cell which is in a regeneration cycle.

59. A method of operating an electrochemical cell comprising a pair of electrodes about an ion exchange membrane, the method comprising:

(a) in a fluid deionization cycle, passing fluid into the cell while powering the electrodes to deionize the fluid to form deionized fluid; and

(b) in a regeneration cycle, providing a timed burst of fluid into the cell while powering the electrodes to regenerate the ion exchange membrane.

60. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, and an ion exchange membrane between a pair of electrodes;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the orifices of the cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into an orifice of the cell while controlling the power supply to supply a current to the electrodes to deionize the fluid to form deionized fluid which is released at another orifice;

(2) in a regeneration cycle, open the valve to flow fluid into an orifice of the cell and control the power supply to;

(i) in a main regeneration step, supply a current having a polarity to the electrodes to regenerate the ion exchange membrane to form regenerate fluid which is released at another orifice; and

(ii) in a post regeneration step, reverse the polarity of the current, whereby the concentration of residual ions in the fluid in the cell is reduced.

61. An apparatus according to claim 60 wherein in the post regeneration step, the controller supplies the current for a time period of at least about 0.5 minutes.

62. An apparatus according to claim 60 wherein at the end of the post regeneration step, the controller terminates the reverse polarity current supplied to the electrodes while maintaining the valve open to allow a volume of fluid to continue to flow into the orifice of the cell, the volume being at least 20% of the cell void volume.

63. A fluid treatment method conducted in an electrochemical cell, the method comprising:

(a) in a deionization cycle, flowing fluid into the cell while passing a current through the fluid to form deionized fluid which is released from the cell;

(b) in a regeneration cycle, flowing fluid into the cell and

(i) in a main regeneration step, passing a current having a polarity through the fluid to regenerate the ion exchange membrane to form regenerate fluid which is released from the cell; and

(ii) in a post regeneration step, reversing the polarity of the current, whereby the concentration of residual ions in the fluid in the cell is reduced.

64. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having inlet and deionized fluid orifices, and an ion exchange membrane between first and second electrodes, the first electrode being adjacent to the inlet orifice and the second electrode adjacent to the deionized fluid orifice;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the inlet and deionized fluid orifices of the cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into the inlet fluid orifice of the cell while controlling the power supply to supply a current having a first positive polarity to the first electrode to deionize the fluid to form deionized fluid which is released at the deionized fluid orifice;

(2) in a regeneration cycle, open the valve to flow fluid into the deionized fluid orifice of the cell while controlling the power supply to supply a current having a first positive polarity to the second electrode to regenerate the ion exchange membrane to form regenerate fluid which is released from the inlet orifice.

65. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having inlet and deionized fluid orifices, and an ion exchange membrane between first and second electrodes, the first electrode being adjacent to the inlet orifice and the second electrode adjacent to the deionized fluid orifice;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the inlet and deionized fluid orifices of the cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into the inlet fluid orifice of the cell while controlling the power supply to supply a current to the first electrode to deionize the fluid to form deionized fluid which is released at the deionized fluid orifice;

(2) in a regeneration cycle, open the valve to flow deionized fluid into the inlet fluid orifice of the cell while controlling the power supply to supply a current having a first positive polarity to the second electrode to regenerate the ion exchange membrane to form regenerate fluid which is released from the deionized fluid orifice.

66. An apparatus according to claim 65 wherein the deionized fluid has a conductivity of less than 50% that of the fluid treated during the deionization cycle.

68. An apparatus according to claim 65 wherein the controller opens the valve to flow deionized fluid into the deionized fluid orifice.

69. An apparatus according to claim 65 wherein the second electrode is maintained at a positive polarity.

70. An apparatus according to claim 65 wherein the time modulated current comprises a first current and a second current, and wherein the first current is greater than the second current.

71. An apparatus according to claim 65 wherein the duty cycle for the first current is larger than that of the second current

67. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having inlet and deionized fluid orifices, and an ion exchange membrane between first and second electrodes, the first electrode being adjacent to the inlet orifice and the second electrode adjacent to the deionized fluid orifice;

(b) a variable voltage supply that provides a time modulated direct current voltage to the electrodes of the cell, the time modulated direct current voltage having a single polarity that remains either positive or negative;

(c) a valve to control the flow of fluid through the inlet and deionized fluid orifices of the cell; and

(d) a controller to, in a regeneration cycle, open the valve to flow fluid into the deionized fluid orifice of the cell while controlling the variable voltage supply to supply a time modulated direct current voltage to the electrodes of the cell.

72. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, and an ion exchange membrane between a pair of electrodes;

(b) a power supply to supply a current to the electrodes;

(c) a valve to control the flow of fluid through the orifices of the cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into an orifice of the cell while controlling the power supply to supply a current having a current density to the pair of electrodes to form deionized fluid which is released at another orifice; and

(2) in a regeneration cycle, open the valve to supply deionized fluid to an orifice while controlling the power supply to supply a modulated regeneration current to the electrodes.

73. A fluid treatment apparatus comprising:

(a) first and second electrochemical cells, each electrochemical cell comprising;

(i) a housing comprising a pair of electrodes;

(ii) a water-splitting membrane between the electrodes; and

(iii) a fluid inlet and a fluid outlet;

(b) a power supply to supply current to the electrodes of the first and second electrochemical cells;

(c) a valve system comprising a plurality of solenoid valves comprising;

(d) a controller to control (i) the power supply to switch the power supply on and off, and regulate a current applied by the power supply to the electrodes of the first and second electrochemical cells, and (ii) controls the plurality of solenoid valves of the valve system to regulate the flow of fluid through the first and second electrochemical cells.

74. An apparatus according to claim 73 comprising at least four solenoid valves.

75. An apparatus according to claim 73 comprising a pipe having a first fork that splits the fluid flowing therethrough to pass the fluid to either of the first and second electrochemical cells, and wherein first solenoid valves are positioned in the pipe between the first fork and each of the electrochemical cells.

76. An apparatus according to claim 73 comprising a pipe having a second fork between the first solenoid valves and the electrochemical cells to allow fluid flowing therethrough to flow to the electrochemical cells or to a drain, and further comprising second solenoids between the second fork and the drain to controls the flow of the fluid to the drain.

77. An apparatus according to claim 73 further comprising a solenoid valve positioned in the pipe leading to the treated fluid outlet.

78. An apparatus according to claim 73 further comprising a fluid flow sensor to measure a flow rate of the fluid passing through the electrochemical cells.

79. An apparatus according to claim 73 wherein the fluid flow sensor comprises a Hall Effect sensor.

80. An apparatus according to claim 73 further comprising a pressure sensor to measure a pressure of the fluid.

81. An apparatus according to claim 73 wherein the pressure sensor to provides a pressure signal to the controller, and wherein the controller switches off operation of the electrochemical cells upon receiving a pressure signal that indicates a sufficiently high pressure.

82. An apparatus according to claim 73 further comprising a fluid holding tank, and wherein the pressure sensor is mounted in the tank to measure a pressure of the fluid in the tank.

83. An apparatus according to claim 73 further comprising at least one of:

(1) a sediment filter to filter particulates out of the fluid;

(2 an activated carbon filter;

(3) an ultraviolet antimicrobial filter; and

(4) a N-halamine cell.

84. An apparatus according to claim 73 further comprising a dosing component with a dosing solenoid valve to periodically or continuously supply a dose of an antimicrobial agent to the fluid.

85. An apparatus according to claim 73 comprising a pair of power supplies.

86. An apparatus according to claim 85 comprising a first power supply connected only to the first electrochemical cell, and a second power supply connected only to the second electrochemical cell.

87. An apparatus according to claim 85 wherein each power supply is capable of outputting a voltage from between about −

300 volts and +300 volts.

88. An apparatus according to claim 85 wherein the first power supply comprises a first output terminal having an always positive polarity, and the second power supply comprises a first output terminal having an always negative polarity.

89. An apparatus according to claim 85 wherein each power supply is independently connected to both the first and second cells and can power either cell in a deionization or regeneration mode.

90. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising

(i) a plurality of fluid orifices to receive an input fluid and release an output fluid;

(ii) a first pair of inner and outer electrodes that are each composed of the same first material;

(iii) a second pair of inner and outer electrodes are each composed of the same second material that is a different material from the first material; and

(iii) an ion exchange membrane between the first and second pairs of inner and outer electrodes to treat the input fluid to form the output fluid; and

(b) a power supply to supply a current to operate the first pair of inner and outer electrodes only as an anode, and the second pair of inner and outer electrode only as a cathode.

91. An apparatus according to claim 90 wherein the first pair of inner and outer electrodes are made from a first material that reduces corrosion of a positive polarity electrode by the ions in the fluid.

92. An apparatus according to claim 90 wherein the first pair of inner and outer electrodes comprise dimensionally stable anodes.

93. An apparatus according to claim 90 wherein the dimensionally stable anodes comprise an electrically conductive substrate with a surface coating.

94. An apparatus according to claim 90 wherein electrically conductive substrate comprise titanium, tantalum, niobium or zirconium.

95. An apparatus according to claim 90 wherein the surface coating comprises platinum, ruthenium, palladium, iridium, rhodium or osmium.

96. An apparatus according to claim 90 wherein the dimensionally stable anodes comprise a titanium with a surface coating comprising ruthenium dioxide.

97. An apparatus according to claim 90 wherein the second pair of inner and outer electrodes are each composed of carbon or stainless steel.

98. An apparatus according to claim 90 wherein the inner electrodes are positioned side by side and have an insulator coating on adjacent portions of each of the inner electrodes, and the outer electrodes are positioned side by side and have an insulator coating on adjacent portions of each of the outer electrodes.

99. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, and an ion exchange membrane between a pair of electrodes;

(b) a power supply to supply a current to the electrodes;

(c) a valve to control the flow of fluid through the orifices of the cell;

(d) a scale inhibitor drip system for dripping a scale inhibitor reagent into the fluid to inhibit scale formation in the electrochemical cell; and

(d) a controller to;

(1) in a deionization cycle, open the valve to flow fluid into an orifice of the cell while controlling the power supply to supply a current having a current density to the pair of electrodes to form deionized fluid which is released at another orifice; and

(2) in a regeneration cycle, open the valve to supply deionized fluid to an orifice while controlling the power supply to supply a modulated regeneration current to the electrodes.

100. An apparatus according to claim 99 wherein the scale inhibitor drip system drips a scale inhibitor reagent into the fluid during the regeneration cycle.

101. An apparatus according to claim 99 wherein scale inhibitor drip system drips a scale inhibitor reagent into the fluid to maintain the fluid at a pH of less than 7.

102. An apparatus according to claim 101 wherein scale inhibitor reagent comprises a phosphate, hydrochloric acid, phosphoric acid, sulfuric acid, citric acid, sulfamic acid or malic acid.

103. A fluid treatment apparatus comprising:

(a) an electrochemical cell comprising a housing having a plurality of orifices, a pair of electrodes, and an ion exchange membrane between the electrodes;

(b) a power supply to supply a current to the electrodes of the cell;

(c) a valve to control the flow of fluid through the orifices of the cell;

(d) a temperature sensor to measure a temperature of the fluid and generate a temperature signal; and

(e) a controller to control the power supply and valve to;

(1) in a deionization cycle, open the valve to flow fluid into an orifice of the cell while controlling the power supply to supply a current to the electrodes to deionize the fluid to form deionized fluid which is released at another orifice;

(2) in a regeneration cycle, open the valve to flow fluid into an orifice of the cell and control the power supply to supply a current to the electrodes to regenerate the ion exchange membrane to form regenerate fluid which is released at another orifice, and

wherein in either or both of the deionization and regeneration cycles, the controller receives the temperature signal and selects the current supplied to the electrodes in relation to the temperature signal.