Boiling coolant ozone generator

• US 4,411,756 A
• Filed: 03/31/1983
• Issued: 10/25/1983
• Est. Priority Date: 03/31/1983
• Status: Expired due to Fees

• Current Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Bennett, Douglas L., Amoss, Donald C.
• Primary Examiner(s): Niebling, John F.
• Application Number:
  US06/481,026
• Time in Patent Office: 208 Days
• Field of Search: 204/176, 422/186.18, 422/186.19, 422/186.2
• US Class Current: 204/176
• CPC Class Codes: B01J 19/088 giving rise to electric discharges for heating purposes H05B7/00; for the production of ozone C01B13/11, H01T19/00
• CPC Class Codes: B01J 2219/0849 Corona pulse discharge
• CPC Class Codes: C01B 13/11 by electric discharge
• CPC Class Codes: C01B 2201/10 Dischargers used for production of ozone
• CPC Class Codes: C01B 2201/24 Composition of the electrodes
• CPC Class Codes: C01B 2201/34 Composition of the dielectrics
• CPC Class Codes: C01B 2201/70 Cooling of the discharger; Means for making cooling unnecessary
• CPC Class Codes: C01B 2201/74 by liquid
• CPC Class Codes: C02F 1/78 with ozone C02F1/4672 takes precedence
• CPC Class Codes: F28D 15/02 in which the medium condenses and evaporates, e.g. heat pipes heat pipes used in solar heat collectors F24S10/95; in radiators F28D1/0226; in nuclear reactors G21C15/257

Abstract

An ozone generator is set forth wherein the production of ozone is increased by the more efficient cooling of the generator electrodes and therefore the discharge gap where the ozone forms. The cooling is effected by the use of a boiling coolant fluid which has a high heat transfer capacity. Additionally the electrode structure is made more rigid for increased life in the presence of boiling cooling fluid. A method of ozone preparation is also set forth. Alternately cooling can be enhanced by the introduction of a gas into the coolant to enhance coolant turbulence without boiling the coolant.

Claims

1. In an apparatus for producing ozone from an oxygen-containing gas by corona discharge, comprising two spaced electrodes supplied by a high voltage, and means for cooling the ozone by contacting an electrode with a coolant, the improvement comprising means for effecting the boiling of the coolant utilizing the heat in the generator whereby the resulting boiling coolant fluid contacts at least one electrode in heat exchange communication so as to enhance the heat transfer capability and to extend the life of the apparatus.

2. The apparatus according to claim 1 wherein a dielectric material is interposed between the electrodes.

3. The apparatus according to claim 2 wherein said means for cooling includes a boiling coolant fluid which contacts both electrodes.

4. The apparatus according to claim 3 wherein said electrodes have a tubular configuration and are disposed concentrically within a container which forms a cooling fluid chamber with an inner cooling zone which is interior to the inner concentric electrode and an outer cooling zone which is exterior to the outer electrode.

5. The apparatus according to claim 4 wherein said chamber comprises means for recycling the boiling coolant fluid.

6. The apparatus according to claim 5 wherein said recycling means comprises a thermo siphon consisting of a condenser for condensing the vapor of said boiling coolant fluid and a return path for said condensed coolant.

7. The apparatus according to claim 5 wherein said recycling means includes a pump that recirculates condensed coolant to the electrodes.

8. The apparatus according to claim 1 further comprising a tube concentrically positioned between said outer electrode and said container to form an annular baffle which prevents the reduction of the effective dielectric strength of the coolant outside the baffle.

9. The apparatus according to claim 4 wherein said outer electrode and said dielectric material comprise a glass lined stainless steel pipe.

10. The apparatus according to claim 9 wherein said pipe has a minimum wall thickness of 0.01 inches.

11. The apparatus according to claim 4 wherein said inner electrode comprises a stainless steel pipe lined with said dielectric material.

12. The apparatus according to claim 4 wherein said inner electrode comprises an aluminum pipe lined with said dielectric material.

13. The apparatus according to claim 4 wherein said boiling coolant fluid comprises a fluorocarbon.

14. The apparatus according to claim 4 wherein the means for effecting boiling comprises electrodes having a rough surface in contact with said boiling coolant fluid.

15. The apparatus according to claim 1 wherein the means for effecting boiling comprises apparatus including a heater at the lower region of at least one electrode.

16. The apparatus according to claim 1 wherein at least one electrode comprises the source of heat to cause the coolant to boil.

17. In a method for producing ozone in an ozone generator comprising generating ozone from an oxygen-containing gas by corona discharge between two spaced electrodes and cooling the ozone by contacting an electrode with a coolant, the improvement for providing an enhanced heat transfer capability and resulting improved ozone production efficiency comprising cooling said ozone by contacting at least one electrode in heat exchange communication with a boiling coolant fluid whereby the heat in the generator causes the coolant to boil.

18. The method of claim 17 wherein a dielectric material is interposed between said electrodes.

19. The method of claim 17 wherein the vapor of the boiling coolant fluid is condensed and recycled past the electrodes.

20. The method of claim 19 wherein the coolant fluid is recycled by the thermo-siphon effect.

21. The method of claim 17 wherein both electrodes are contacted with the boiling coolant fluid.

22. The method of claim 17, wherein the coolant is a fluorocarbon.

23. The method of claim 19 wherein the condensed coolant fluid is recycled by a pump.

24. The method of claim 17 wherein the heat generated by ozone production causes the coolant to boil.

25. The method of claim 17 wherein the heat of at least one electrode causes the coolant to boil.

26. The method of claim 17 wherein the heat causing the coolant to boil is supplied at least in part from an auxiliary heater.

27. In an apparatus for producing ozone from an oxygen-containing gas by corona discharge, comprising two spaced electrodes supplied by a high voltage, and means for cooling the ozone by contacting an electrode with a coolant, the improvement comprising means for creating bubbles in the coolant utilizing a gas whereby the resulting two phase coolant fluid contacts at least one electrode in heat exchange communication so as to enhance the heat transfer capability and to extend the life of the apparatus.

28. The apparatus of claim 27 wherein said means for creating bubbles in the coolant comprises a nozzle which discharges a gas into the coolant.

29. In a method for producing ozone in an ozone generator comprising generating ozone from an oxygen-containing gas by corona discharge between two spaced electrodes and cooling the ozone by contacting an electrode with a coolant, the improvement for providing an enhanced heat transfer capability and resulting improved ozone production efficiency comprising cooling said ozone by contacting at least one electrode in heat exchange communication with a two phase coolant fluid whereby a gas introduced into the generator causes the coolant to have increased turbulence.