Flow-through oxygenator

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.

The invention claimed is: 
     
       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. An emitter for electrolytic generation of bubbles of oxygen in water, the emitter comprising:
 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 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;   the power source being operable to deliver electrical current to the electrodes while water flows through the tubular housing and is in contact with the electrodes to produce oxygen in said water via electrolysis.    
     
     
       14. The emitter of claim 13 wherein the tubular housing includes an inward-facing surface that runs parallel to the longitudinal axis;
 wherein the electrodes extend in a direction that is parallel to the longitudinal axis; and   wherein at least one of the first and second electrodes is positioned in the tubular housing closer to the inward-facing surface than said distance separating the electrodes.    
     
     
       15. The emitter of claim 13 wherein the tubular housing includes an inward-facing surface that runs parallel to the longitudinal axis;
 wherein said 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 emitter of claim 13 wherein at least one of the electrodes is a stainless steel mesh or screen.  
     
     
       17. The emitter of claim 13 wherein the 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 one of the electrodes positioned within the tubular housing.  
     
     
       18. The emitter 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 emitter 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 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 less than a cross-sectional area of the unobstructed passageway.  
     
     
       20. The emitter of claim 13 wherein the 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 one of the 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 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 less than a cross-sectional area of the unobstructed passageway; and   wherein the tubular housing of the emitter is round.    
     
     
       21. The emitter of claim 19 wherein said inward-facing surface is a concave surface.  
     
     
       22. The emitter of claim 13 further including first and second conductors coupled to the first and second electrodes respectively, the first conductor exiting a wall of the housing in a radial direction relative to the longitudinal axis of the housing, the second conductor exiting a wall of the housing in a radial direction relative to the longitudinal axis of the housing.  
     
     
       23. The emitter 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.  
     
     
       24. The emitter of claim 13 wherein the at least two electrodes includes a first anode electrode portion that is nonparallel to a second anode electrode portion, the first and second anode electrode portions each being parallel to respective opposing cathode electrode portions.  
     
     
       25. 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 and 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 said distance separating the inside electrode from the outside electrode; and   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;   the power source being operable to deliver electrical current to the electrodes while water flows through the chamber of the tubular housing and is in contact with the electrodes to produce oxygen in said water via electrolysis.    
     
     
       26. The emitter of claim 25 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.  
     
     
       27. The emitter of claim 25 wherein the 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 one of the electrodes positioned within the chamber.  
     
     
       28. The emitter of claim 27 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.  
     
     
       29. The emitter of claim 28 wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward-facing surface of the chamber that is less than a cross-sectional area of said unobstructed passageway.  
     
     
       30. The emitter of claim 25 further including first and second conductors coupled to the outside and inside electrodes respectively, the first conductor exiting a wall of the housing in a radial direction relative to a longitudinal center axis of the housing, the second conductor exiting a wall of the housing in a radial direction relative to a longitudinal center axis of the housing.  
     
     
       31. The emitter of claim 25 wherein the oxygen produced comprises nanobubbles.  
     
     
       32. The emitter of claim 25 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.  
     
     
       33. The emitter of claim 25 wherein the at least two electrodes includes a first anode electrode portion that is nonparallel to a second anode electrode portion, the first and second anode electrode portions each being parallel to respective opposing cathode electrode portions.  
     
     
       34. 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, 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, said portion being a portion that opposes the other of the first and second electrodes, 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 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;   the power source being operable to deliver electrical current to the electrodes while water flows through the tubular housing and is in contact with the electrodes to produce oxygen in said water via electrolysis.    
     
     
       35. The emitter of claim 34 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 all points midway between all opposing electrodes inside the chamber are closer to said inwardly-facing surface than to the longitudinal center axis.    
     
     
       36. The emitter of claim 34 wherein the chamber has a longitudinal center axis and an inward-facing surface that runs parallel to the longitudinal axis, wherein the electrodes extend in a direction that is parallel to the longitudinal axis, and wherein at least one of the first and second electrodes is positioned in the chamber closer to the inward-facing surface than said distance separating the electrodes.  
     
     
       37. The emitter of claim 36 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.  
     
     
       38. The emitter of claim 34 wherein the electrode in contact with a wall of the tubular housing is in contact with a curved wall of the tubular housing.  
     
     
       39. The emitter of claim 34 wherein the 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 one of the electrodes positioned within the chamber.  
     
     
       40. The emitter of claim 39 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.  
     
     
       41. The emitter of claim 39 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 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 less than a cross-sectional area of the unobstructed passageway.    
     
     
       42. The emitter of claim 34 further including first and second conductors coupled to the first and second electrodes respectively, the first conductor exiting a wall of the housing in a radial direction relative to a longitudinal axis of the housing, the second conductor exiting a wall of the housing in a radial direction relative to the longitudinal axis of the housing.  
     
     
       43. The emitter of claim 34 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.  
     
     
       44. The emitter of claim 34 wherein the at least two electrodes includes a first anode electrode portion that is nonparallel to a second anode electrode portion, the first and second anode electrode portions each being parallel to respective opposing cathode electrode portions.  
     
     
       45. An emitter for electrolytic generation of bubbles of oxygen in an aqueous medium comprising:
 a tubular housing defining an oxygenation chamber, and having an inward-facing surface that defines at least in part the oxygenation chamber, 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 and 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 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.    
     
     
       46. The emitter of claim 45 wherein at least one of the inside and outside electrodes is positioned in the chamber closer to the inward-facing surface than said distance separating the electrodes, and wherein the tubular housing defines a longitudinal center axis that lies in the oxygenation chamber and wherein the unobstructed passageway includes the longitudinal center.  
     
     
       47. The emitter of claim 45 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.  
     
     
       48. The emitter of claim 47 wherein the electrode in contact with a wall of the tubular housing is in contact with a curved wall of the tubular housing.  
     
     
       49. The emitter of claim 45 wherein the unobstructed passageway is multiple times wider than the distance separating the opposing inner and outer electrodes within the chamber.  
     
     
       50. The emitter of claim 49 wherein the outside electrode defines a cross-sectional area between the outside electrode and the inward-facing surface of the chamber that is less than a cross-sectional area of said unobstructed passageway.  
     
     
       51. The emitter of claim 50 wherein said inward-facing surface is a concave surface.  
     
     
       52. The emitter of claim 45 further including first and second conductors coupled to the outside and inside electrodes respectively, the first conductor exiting a wall of the housing in a radial direction relative to a longitudinal center axis of the housing, the second conductor exiting a wall of the housing in a radial direction relative to the longitudinal center axis of the housing.  
     
     
       53. The emitter of claim 45 coupled to a power source 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.  
     
     
       54. The emitter of claim 45 wherein the at least two electrodes includes a first anode electrode portion that is nonparallel to a second anode electrode portion, the first and second anode electrode portions each being parallel to respective opposing cathode electrode portions.  
     
     
       55. An emitter for electrolytic generation of bubbles of oxygen in an aqueous medium comprising:
 a tubular housing defining an oxygenation chamber, said housing having an outer wall that runs parallel to a longitudinal center axis of the housing, said 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, 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 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 one of the electrodes positioned within the chamber, the unobstructed passageway having a uniform cross-sectional area along that length, the 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 less than said cross-sectional area of the unobstructed passageway.    
     
     
       56. The emitter of claim 55 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.  
     
     
       57. The emitter of claim 56 wherein the electrode in contact with a wall of the tubular housing is in contact with the outer wall which is a curved wall of the tubular housing.  
     
     
       58. The emitter of claim 55 wherein the unobstructed passageway is multiple times wider than the distance separating the opposing outside and inside electrodes within the chamber.  
     
     
       59. The emitter of claim 55 wherein said outer wall includes an inwardly-facing concave surface.  
     
     
       60. The emitter of claim 55 further including first and second conductors coupled to the outside and inside electrodes respectively, the first conductor exiting a wall of the housing in a radial direction relative to the longitudinal center axis of the housing, the second conductor exiting a wall of the housing in a radial direction relative to the longitudinal center axis of the housing.  
     
     
       61. The emitter of claim 55 wherein the at least two electrodes includes a first anode electrode portion that is nonparallel to a second anode electrode portion, the first and second anode electrode portions each being parallel to respective opposing cathode electrode portions.