Flow-through oxygenator

• US RE47,092 E1
• Filed: 03/30/2016
• Issued: 10/23/2018
• Est. Priority Date: 02/22/2002
• Status: Expired due to Term

• Current Assignee: Oxygenator Water Technologies, Inc.
• Original Assignee: Oxygenator Water Technologies, Inc.
• Inventors: Senkiw, James Andrew
• Primary Examiner(s): JASTRZAB, KRISANNE MARIE
• Application Number:
  US15/085,741
• Time in Patent Office: 937 Days
• CPC Class Codes: A01G 31/00 Soilless cultivation, e.g. hydroponics growth substrates therefor A01G24/00; cultivation of seaweed A01G33/00
• CPC Class Codes: A01G 31/02 Special apparatus therefor self-acting watering devices A01G27/00
• CPC Class Codes: A01K 63/042 Introducing gases into the water, e.g. aerators, air pumps
• CPC Class Codes: C02F 1/46104 Devices therefor; Their operating or servicing
• CPC Class Codes: C02F 1/46109 Electrodes
• CPC Class Codes: C02F 1/4672 by electrooxydation
• CPC Class Codes: C02F 1/68 by addition of specified substances, e.g. trace elements, for ameliorating potable water medicinal water A61K
• CPC Class Codes: C02F 1/727 using pure oxygen or oxygen rich gas
• CPC Class Codes: C02F 2001/46133 characterised by the material
• CPC Class Codes: C02F 2001/46138 Electrodes comprising a substrate and a coating
• 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 2001/46157 Perforated or foraminous electrodes
• CPC Class Codes: C02F 2201/4612 Controlling or monitoring
• CPC Class Codes: C02F 2201/4615 Time
• CPC Class Codes: C02F 2209/02 Temperature
• CPC Class Codes: C02F 2209/44 Time
• CPC Class Codes: C02F 2303/26 Reducing the size of particles, liquid droplets or bubbles, e.g. by crushing, grinding, spraying, creation of microbubbles or nanobubbles
• CPC Class Codes: C02F 3/26 using pure oxygen or oxygen-rich gas
• CPC Class Codes: C02F 7/00 Aeration of stretches of water
• CPC Class Codes: C25B 1/04 by electrolysis of water
• CPC Class Codes: C25B 15/02 : Process control or regulation
• CPC Class Codes: C25B 9/06 : Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof
• CPC Class Codes: Y02E 60/366 : by electrolysis of water
• CPC Class Codes: Y02P 60/216 : Aquaponics or hydroponics
• CPC Class Codes: Y02W 10/15 : Aerobic processes

Abstract

An oxygen emitter which is an electrolytic cell is disclosed. When the anode and cathode are separated by a critical distance, very small microbubbles and nanobubbles of oxygen are generated. The very small oxygen bubbles remain in suspension, forming a solution supersaturated in oxygen. A flow-through model for oxygenating flowing water is disclosed. The use of supersaturated water for enhancing the growth of plants is disclosed. Methods for applying supersaturated water to plants manually, by drip irrigation or in hydroponic culture are described. The treatment of waste water by raising the dissolved oxygen with the use of an oxygen emitter is disclosed.

Claims

1. A method for treating waste water comprising;

providing a flow-through oxygenator comprising an emitter for electrolytic generation of microbubbles of oxygen comprising an anode separated at a critical distance from a cathode and a power source all in electrical communication with each other,

placing the emitter within a conduit; and

passing waste water through the conduit.

2. An emitter for electrolytic generation of microbubbles of oxygen in an aqueous medium comprising:

an anode separated at a critical distance from a cathode, a nonconductive spacer maintaining the separation of the anode and cathode, the nonconductive spacer having a spacer thickness between 0.005 to 0.050 inches such that the critical distance is less than 0.060 inches and a power source all in electrical communication with each other, wherein the critical distance results in the formation of oxygen bubbles having a bubble diameter less than 0.0006 inches, said oxygen bubbles being incapable of breaking the surface tension of the aqueous medium such that said aqueous medium is supersaturated with oxygen.

3. The emitter of claim 2, wherein the anode is a metal or a metallic oxide or a combination of a metal and a metallic oxide.

4. The emitter of claim 2, wherein the anode is platinum and iridium oxide on a support.

5. The emitter of claim 2, wherein the cathode is a metal or metallic oxide or a combination of a metal and a metallic oxide.

6. The emitter of claim 2, wherein the critical distance is 0.005 to 0.060 inches.

7. The emitter of claim 2, comprising a plurality of anodes separated at the critical distance from a plurality of cathodes.

8. A method for oxygenating a non-native habitat for temporarily keeping aquatic animals, comprising:

inserting the emitter of claim 2 into the aqueous medium, the non-native habitat comprising an aquarium, a bait bucket or a live well.

9. A method for lowering the biologic oxygen demand of polluted water comprising:

passing the polluted water through a vessel containing the emitter of claim 2.

10. A supersaturated aqueous product formed with the emitter of claim 2, the supersaturated aqueous product having an approximately neutral pH.

11. The emitter of claim 2, further comprising a timer control.

12. The emitter of claim 2, wherein the anode and cathode are arranged such that the emitter assumes a funnel or pyramidal shaped emitter.

13. A method for treating water comprising:

providing a flow-through oxygenator comprising an emitter for electrolytic generation of bubbles of oxygen, the emitter including;

a tubular housing having a water inlet, a water outlet, and a longitudinal water flow axis from the inlet to the outlet;

at least two electrodes comprising a first electrode and a second electrode, the first and second electrodes being positioned in the tubular housing, the first electrode opposing and separated from the second electrode by a distance of between 0.005 inches to 0.140 inches within the tubular housing;

each electrode of the emitter is positioned so that substantially all points midway between all opposing electrodes are closer to a surface of the tubular housing than to a center point within the tubular housing and so that at least some water may flow from the water inlet to the water outlet without passing through a space between electrodes of opposite polarity separated by a distance of between 0.005 inches to 0.140 inches;

a power source in electrical communication with the electrodes, the power source configured to deliver a voltage to the electrodes, the voltage being less than or equal to 28.3 volts, the power source being configured to deliver a current to the electrodes, the current being less than or equal to 12.8 amps;

passing water through the tubular housing while electrical current is applied to the electrodes producing oxygen in said water via electrolysis.

14. The method of claim 13 wherein the tubular housing includes an inward-facing surface that runs parallel to the longitudinal axis;

wherein the first and second electrodes extend in a direction that is parallel to the longitudinal axis.

15. The method of claim 13 wherein the tubular housing includes an inward-facing surface that runs parallel to the longitudinal axis;

wherein the first and second electrodes extend in a direction parallel to the longitudinal axis; and

wherein each electrode of the emitter is positioned closer to the inward-facing surface than to the longitudinal axis at the center of the tubular housing.

16. The method of claim 13 wherein at least one of the electrodes is a stainless steel mesh or screen.

17. The method of claim 13 wherein the first and second electrodes are positioned away from a longitudinal center axis of the tubular housing and maintain an unobstructed passageway parallel to the center axis, the passageway running longitudinally for at least the length of the first and second electrodes positioned within the tubular housing.

18. The method of claim 17 wherein the unobstructed passageway includes the center axis and is multiple times wider than the distance separating the opposing first and second electrodes within the tubular housing.

19. The method of claim 17 wherein the first and second electrodes comprise an outside electrode and an inside electrode,

wherein the first and second electrodes extend in a longitudinal direction parallel to the longitudinal axis and an inward-facing surface of the tubular housing, the outside and inside electrodes being outside and inside electrodes respectively in that the first and second electrodes are positioned relative to each other so that the outside electrode is closer to an outer wall of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal axis at the center of the tubular housing than the outside electrode is,

wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward facing surface of the tubular housing that is substantially less than a cross-sectional area of the unobstructed passageway.

20. The method of claim 13 wherein the first and second electrodes are positioned away from a longitudinal center axis of the tubular housing and maintain an unobstructed passageway parallel to and including the center axis, the passageway running for at least the length of the first and second electrodes positioned within the housing;

wherein the first and second electrodes comprise an outside electrode and an inside electrode;

wherein the first and second electrodes extend in a longitudinal direction parallel to the longitudinal axis and an inward-facing surface of the tubular housing;

the outside and inside electrodes being outside and inside electrodes respectively in that the first and second electrodes are positioned relative to each other so that the outside electrode is closer to an outer wall of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal axis at the center of the tubular housing than the outside electrode is;

wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward facing surface of the tubular housing that is substantially less than a cross-sectional area of the unobstructed passageway; and

wherein the tubular housing of the emitter is round.

21. The method of claim 19 wherein said inward-facing surface is a concave surface.

22. The method of claim 13 further including at least one conductor coupled to one of the first and second electrodes, the at least one conductor exiting a wall of the housing in a radial direction relative to the longitudinal axis of the housing.

23. The method of claim 13 wherein the oxygen produced comprises microbubbles.

24. The method of claim 13 wherein the power source delivers a current to the electrodes at a ratio of 1.75 amps or less per 3 square inches of active electrode.

25. The method of claim 13 wherein the first electrode includes a first anode element and the second electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

26. The method of claim 13 wherein the oxygen produced comprises nanobubbles.

27. An emitter for electrolytic generation of bubbles of oxygen in water, the emitter comprising:

a tubular housing defining an oxygenation chamber and having a water inlet, a water outlet, a longitudinal water flow axis from the inlet to the outlet, and an inward-facing surface that runs parallel to the water flow axis and defines at least in part the oxygenation chamber;

at least two electrodes comprising an outside electrode and an inside electrode, the outside and inside electrodes being positioned in the oxygenation chamber, said outside and inside electrodes extending in a direction that is parallel to the longitudinal axis, the outside electrode opposing and separated from the inside electrode by a distance of between 0.005 inches to 0.140 inches within the chamber,

wherein the position and size of each electrode within the chamber defines a cross-section of the chamber that has a water flow area within the oxygenation chamber through which water may flow without passing between electrodes of opposite polarity that are separated by a distance of between 0.005 inches to 0.140 inches, wherein the water flow area is greater than an area at the cross-section equal to the total area between electrodes of opposite polarity that are separated by a distance of between 0.005 inches to 0.140 inches,

wherein at least a portion of the outside electrode positioned in the chamber is closer to the inward-facing surface of the oxygenation chamber than to a longitudinal center axis of the oxygenation chamber; and

a power source in electrical communication with the outside and inside electrodes, the power source configured to deliver a voltage to the outside and inside electrodes, the voltage being less than or equal to 28.3 volts, the power source being configured to deliver a current to the outside and inside electrodes, the current being less than or equal to 12.8 amps.

28. The emitter of claim 27 wherein each electrode is positioned closer to the inward-facing surface of the chamber than to the longitudinal center axis of the oxygenation chamber.

29. The emitter of claim 27 wherein the outside and inside electrodes are positioned away from the longitudinal center axis of the tubular housing and maintain an unobstructed passageway parallel to the center axis, the passageway running longitudinally for at least the length of the outside and inside electrodes positioned within the chamber.

30. The emitter of claim 29 wherein the unobstructed passageway includes the center axis and is multiple times wider than the distance separating the opposing inner and outer electrodes within the chamber.

31. The emitter of claim 30 wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward-facing surface of the chamber that is substantially less than a cross-sectional area of said unobstructed passageway.

32. The emitter of claim 27 comprising at least one conductor coupled to one of the outside and inside electrodes, the at least one conductor exiting a wall of the housing in a radial direction relative to the longitudinal center axis of the housing.

33. The emitter of claim 27 wherein the power source is configured to deliver a current to the electrodes at a ratio of 1.75 amps or less per 3 square inches of active electrode.

34. The emitter of claim 27 wherein the outer electrode includes a first anode element and the inner electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

35. A method for treating water comprising:

providing a flow-through oxygenator comprising an emitter for electrolytic generation of bubbles of oxygen, the emitter including;

a tubular housing defining an oxygenation chamber and having a water inlet, and a water outlet;

at least two electrodes comprising a first electrode and a second electrode, the first and second electrodes being positioned in the oxygenation chamber, the first electrode opposing and separated from the second electrode by a distance of between 0.005 inches to 0.140 inches, a portion of at least one of the first and second electrodes being in contact with at least one wall of the tubular housing, said wall defining at least in part the oxygenation chamber, wherein each electrode is positioned within the oxygenation chamber so that a cross section of the oxygenation chamber includes a water flow area that allows water to avoid passing between electrodes separated by 0.005 inches to 0.140 inches;

a power source in electrical communication with the first and second electrodes, the power source configured to deliver a voltage to the first and second electrodes, the voltage being less than or equal to 28.3 volts, the power source being configured to deliver a current to the first and second electrodes, the current being less than or equal to 12.8 amps;

passing water through the tubular housing while electrical current is applied to the first and second electrodes to produce oxygen in said water via electrolysis.

36. The method of claim 35 wherein the tubular housing has a longitudinal center axis and an inward-facing surface that runs parallel to the longitudinal center axis;

and

wherein each electrode of the emitter is positioned so that substantially all points midway between all opposing electrodes inside the chamber are closer to said inwardly-facing surface than to the longitudinal center axis.

37. The method of claim 35 wherein the chamber has a longitudinal center axis and an inward-facing surface that runs parallel to the longitudinal axis,

wherein the first and second electrodes extend in a direction that is parallel to the longitudinal axis.

38. The method of claim 37 wherein each electrode of the emitter is positioned closer to the inward-facing surface of the chamber than to the longitudinal center axis of the oxygenation chamber.

39. The method of claim 35 wherein the at least one electrode in contact with a wall of the tubular housing is in contact with a curved wall of the tubular housing.

40. The method of claim 35 wherein the outside and inside electrodes are positioned away from a longitudinal center axis of the tubular housing and maintain an unobstructed passageway parallel to the center axis, the passageway running longitudinally for at least the length of the outside and inside electrodes positioned within the chamber.

41. The method of claim 40 wherein the unobstructed passageway includes the center axis and is multiple times wider than the distance separating the opposing first and second electrodes within the chamber.

42. The method of claim 40 wherein the chamber has an inward-facing surface that runs parallel to the longitudinal axis;

wherein the first and second electrodes being outside and inside electrodes respectively in that the first and second electrodes are positioned relative to each other so that the outside electrode is closer to an outer wall of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal axis at the center of the tubular housing than the outside electrode is; and

wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward facing surface of the tubular housing that is substantially less than a cross-sectional area of the unobstructed passageway.

43. The method of claim 35 wherein the emitter includes at least one conductor coupled to one of the first and second electrodes, the at least one conductor exiting a wall of the housing in a radial direction relative to a longitudinal axis of the housing.

44. The method of claim 35 wherein the oxygen produced comprises microbubbles.

45. The method of claim 35 wherein the power source delivers a current to the electrodes at a ratio of 1.75 amps or less per 3 square inches of active electrode.

46. The method of claim 35 wherein the first electrode includes a first anode element and the second electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

47. The method of claim 35 wherein the oxygen produced comprises nanobubbles.

48. A method for treating water comprising:

providing a flow-through oxygenator comprising an emitter for electrolytic generation of bubbles of oxygen, the emitter including;

a tubular housing defining an oxygenation chamber, said housing having an inward-facing surface that defines at least in part the oxygenation chamber, the tubular housing having a water inlet, and a water outlet;

at least two electrodes comprising an outside electrode and an inside electrode, the outside and inside electrodes being positioned in the oxygenation chamber, said outside and inside electrodes extending in a direction that runs parallel to the inward-facing surface, the outside and inside electrodes being outside and inside electrodes respectively in that the outside and inside electrodes are positioned relative to each other so that the outside electrode is closer to the inward-facing surface of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal center axis than the outside electrode is, the outside electrode opposing and separated from the inside electrode by a distance of between 0.005 inches to 0.140 inches within the chamber;

wherein each electrode of the emitter is positioned closer to the inward-facing surface of the chamber than to a midpoint of the tubular housing and so that at least some water may flow through an unobstructed passageway from the water inlet to the water outlet without passing through a space between electrodes of opposite polarity separated by a distance of between 0.005 inches to 0.140 inches;

passing water through the oxygenation chamber while applying electrical current to the electrodes to produce oxygen in said water via electrolysis.

49. The method of claim 48 wherein the tubular housing defines a longitudinal center axis that lies in the oxygenation chamber and wherein the unobstructed passageway includes the longitudinal center axis.

50. The method of claim 48 wherein at least one of the outside and inside electrodes is in contact with at least one wall of the tubular housing, said wall defining at least in part the oxygenation chamber.

51. The method of claim 50 wherein the at least one electrode in contact with a wall of the tubular housing is in contact with a curved wall of the tubular housing.

52. The method of claim 48 wherein the unobstructed passageway is multiple times wider than the distance separating the opposing inner and outer electrodes within the chamber.

53. The method of claim 52 wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward-facing surface of the chamber that is substantially less than a cross-sectional area of said unobstructed passageway.

54. The method of claim 53 wherein said inward-facing surface is a concave surface.

55. The method of claim 48 wherein the emitter includes at least one conductor coupled to one of the outside and inside electrodes, the at least one conductor exiting a wall of the housing in a radial direction relative to a longitudinal center axis of the housing.

56. The method of claim 48 wherein the oxygen produced comprises microbubbles of oxygen.

57. The method of claim 48 wherein the electrical current is applied to the electrodes at a ratio of 1.75 amps or less per 3 square inches of active electrode.

58. The method of claim 48 wherein the outside electrode includes a first anode element and the inside electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

59. The method of claim 48 wherein the oxygen produced comprises nanobubbles of oxygen.

60. An emitter for electrolytic generation of bubbles of oxygen in water, the emitter comprising:

a tubular oxygenation chamber, said chamber having an outer wall that runs parallel to a longitudinal center axis of the chamber, said chamber having a water inlet and a water outlet,

at least two electrodes comprising an outside electrode and an inside electrode, the outside and inside electrodes being positioned in the oxygenation chamber, the outside and inside electrodes being outside and inside electrodes respectively in that the electrodes are positioned relative to each other so that the outside electrode is closer to the outer wall of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal center axis than the outside electrode is, the outside electrode opposing and separated from the inside electrode by a distance of between 0.005 inches to 0.140 inches;

the at least two electrodes being positioned away from the center axis and maintaining a longitudinal, unobstructed passageway parallel to and including the center axis that runs for at least the length of the at least two electrodes positioned within the chamber, the unobstructed passageway having a substantially uniform cross-sectional area along that length, the at least two electrodes being positioned so that water may flow from the water inlet to the water outlet without passing through a space between electrodes of opposite polarity separated by a distance of between 0.005 inches to 0.140 inches;

wherein the outside electrode defines a cross-sectional area between the outside electrode and the outer wall of the chamber that is substantially less than said cross-sectional area of the unobstructed passageway.

61. The emitter of claim 60 wherein at least one of the outside and inside electrodes is in contact with at least one wall of the tubular oxygenation chamber.

62. The emitter of claim 61 wherein the at least one electrode in contact with a wall of the tubular oxygenation chamber is in contact with the outer wall, and wherein the outer wall is a curved wall of the oxygenation chamber.

63. The emitter of claim 60 wherein the unobstructed passageway is multiple times wider than the distance separating the opposing outside and inside electrodes within the chamber.

64. The emitter of claim 60 wherein said outer wall includes an inwardly-facing concave surface.

65. The emitter of claim 60 comprising at least one conductor coupled to one of the outside and inside electrodes, the at least one conductor exiting a wall of the chamber in a radial direction relative to the longitudinal center axis of the chamber.

66. The emitter of claim 60 wherein the outside electrode includes a first anode element and the inside electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

67. A method for treating water comprising:

providing a flow-through oxygenator comprising an emitter for electrolytic generation of bubbles of oxygen, the emitter including;

a tubular housing defining an oxygenation chamber and having a water inlet, a water outlet, a longitudinal water flow axis from the inlet to the outlet, and an inward-facing surface that runs parallel to the water flow axis and defines at least in part the oxygenation chamber;

at least two electrodes comprising an outside electrode and an inside electrode, the outside and inside electrodes being positioned in the oxygenation chamber, said outside and inside electrodes extending in a direction that is parallel to the longitudinal axis, the outside electrode opposing and separated from the inside electrode by a distance of between 0.005 inches to 0.140 inches within the chamber,

wherein the position and size of each electrode within the chamber defines a cross-section of the chamber that has a water flow area within the oxygenation chamber through which water may flow without passing between electrodes of opposite polarity that are separated by a distance of between 0.005 inches to 0.140 inches, wherein the water flow area is greater than an area at the cross-section equal to the total area between electrodes of opposite polarity that are separated by a distance of between 0.005 inches to 0.140 inches; and

a power source in electrical communication with the outside and inside electrodes, the power source configured to deliver a voltage to the outside and inside electrodes, the voltage being less than or equal to 28.3 volts, the power source being configured to deliver a current to the outside and inside electrodes, the current being less than or equal to 12.8 amps;

passing water through the oxygenation chamber while electrical current is applied to the outside and inside electrodes within the chamber to produce oxygen in said water via electrolysis.

68. The method of claim 67 wherein each electrode of the emitter is positioned closer to the inward-facing surface of the chamber than to a longitudinal center axis of the oxygenation chamber.

69. The method of claim 67 wherein the outside and inside electrodes of the emitter is positioned away from a longitudinal center axis of the tubular housing and maintain an unobstructed passageway parallel to the longitudinal center axis, the passageway running longitudinally for at least the length of the outside and inside electrodes within the chamber.

70. The method of claim 69 wherein the unobstructed passageway includes the longitudinal center axis and is multiple times wider than the distance separating the opposing inner and outer electrodes within the chamber.

71. The method of claim 70 wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward-facing surface of the chamber that is substantially less than a cross-sectional area of said unobstructed passageway.

72. The method of claim 67 wherein the emitter includes at least one conductor coupled to one of the outside and inside electrodes, the at least one conductor exiting a wall of the housing in a radial direction relative to a longitudinal center axis of the housing.

73. The method of claim 67 wherein the oxygen produced comprises nanobubbles.

74. The method of claim 67 wherein the power source delivers a current to the outside and inside electrodes at a ratio of 1.75 amps or less per 3 square inches of active electrode.

75. The method of claim 67 wherein the outside electrode includes a first anode element and the inside electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

76. The method of claim 75 wherein the oxygen produced comprises nanobubbles.

77. A method for treating water comprising:

providing a flow-through oxygenator comprising an emitter for electrolytic generation of bubbles of oxygen, the emitter including;

a tubular oxygenation chamber, said chamber having an outer wall that runs parallel to a longitudinal center axis of the chamber, said chamber having a water inlet and a water outlet;

at least two electrodes comprising an outside electrode and an inside electrode, the outside and inside electrodes being positioned in the oxygenation chamber, the outside and inside electrodes being outside and inside electrodes respectively in that the outside and inside electrodes are positioned relative to each other so that the outside electrode is closer to the outer wall of the chamber than the inside electrode is and so that the inside electrode is closer to the longitudinal center axis than the outside electrode is, the outside electrode opposing and separated from the inside electrode by a distance of between 0.005 inches to 0.140 inches;

the at least two electrodes of the emitter being positioned away from the longitudinal center axis and maintaining a longitudinal, unobstructed passageway parallel to and including the longitudinal center axis that runs for at least the length of the at least two electrodes positioned within the chamber, the unobstructed passageway having a substantially uniform cross-sectional area along that length, the at least two electrodes of the emitter being positioned so that water may flow from the water inlet to the water outlet without passing through a space between electrodes of opposite polarity separated by a distance of between 0.005 inches to 0.140 inches;

wherein the outside electrode defines a cross-sectional area between the outside electrode and the outer wall of the chamber that is substantially less than said cross-sectional area of the unobstructed passageway; and

passing water through the oxygenation chamber while applying electrical current to the outside and inside electrodes to produce oxygen in said water via electrolysis.

78. The method of claim 77 wherein at least one of the outside and inside electrodes is in contact with at least one wall of the tubular oxygenation chamber.

79. The method of claim 78 wherein the at least one electrode in contact with a wall of the tubular oxygenation chamber is in contact with the outer wall, and wherein the outer wall is a curved wall of the oxygenation chamber.

80. The method of claim 77 wherein the unobstructed passageway is multiple times wider than the distance separating the opposing outside and inside electrodes within the chamber.

81. The method of claim 77 wherein said outer wall includes an inwardly-facing concave surface.

82. The method of claim 77 wherein the emitter includes at least one conductor coupled to one of the outside and inside electrodes, the at least one conductor exiting a wall of the chamber in a radial direction relative to the longitudinal center axis of the chamber.

83. The method of claim 77 wherein the outside electrode includes a first anode element and the inside electrode includes a first cathode element, and wherein the emitter includes a second anode element non-parallel to the first anode element, and wherein the emitter includes a second cathode element non-parallel to the first cathode element.

84. The method of claim 83 wherein the oxygen produced comprises nanobubbles of oxygen.