Disinfection and purification of fluids using focused laser radiation

• US 4,265,747 A
• Filed: 05/22/1979
• Issued: 05/05/1981
• Est. Priority Date: 05/22/1979
• Status: Expired due to Term

• Current Assignee: Zimpro Passavant Environment Systems Incorporated
• Original Assignee: Sterling Drug, Inc. (GlaxoSmithKline PLC)
• Inventors: Copa, William M., Gitchel, Wayne B.
• Primary Examiner(s): Hruskoci, Peter A.
• Application Number:
  US06/041,526
• Time in Patent Office: 714 Days
• Field of Search: 204/DIG. 11, 210/18, 210/50, 210/60, 210/63 R, 210/63 Z, 210/64, 210/150, 210/151, 210/192, 210/194, 210/198 R, 210/205, 219/121 LM, 331/DIG. 1, 422/22-24, 422/29, 422/32
• US Class Current: 210/758
• CPC Class Codes: A61L 2/14 Plasma, i.e. ionised gases
• CPC Class Codes: B01J 19/121 Coherent waves, e.g. laser beams lasers per se H01S3/00
• CPC Class Codes: C02F 1/30 by irradiation
• CPC Class Codes: C02F 1/325 Irradiation devices or lamp constructions
• CPC Class Codes: C02F 1/727 using pure oxygen or oxygen rich gas
• CPC Class Codes: C02F 1/78 with ozone C02F1/4672 takes precedence
• CPC Class Codes: C02F 2101/36 containing halogen
• CPC Class Codes: C02F 2201/3226 Units using UV-light emitting lasers
• CPC Class Codes: C02F 2301/024 Turbulent
• CPC Class Codes: C02F 2301/026 Spiral, helicoidal, radial

Abstract

Disinfection of aqueous media contaminated with microorganisms is effected by contacting said media with a gas phase in which a plasma is generated by focused laser radiation. Similarly, wastewaters containing organic susbstances are purified by contacting them with an oxygen-containing gas phase in which a plasma is generated by focused laser radiation which promotes oxidation of the organic substances to innocuous products.

Claims

1. A process for disinfecting an aqueous fluid contaminated with microorganisms, which comprises contacting said fluid with a gas selected from the group consisting of oxygen, nitrogen, argon, helium, neon, carbon dioxide, and a mixture of two or more of said gases in which a continuous plasma is generated by multiple pulses of focused laser radiation said plasma containing ultraviolet light, ions, X-ray, electrons and neutrons, and rapidly transferring said plasma to said aqueous fluid for a time sufficient to disinfect said aqueous fluid.

2. A process according to claim 1 wherein the gas is an oxygen-containing gas.

3. A process according to claim 2 wherein the laser radiation is obtained from a CO₂ laser of 9.2-10.6 μ

m wavelength.

4. A process according to claim 1 wherein the laser radiation, before focusing, has a wavelength in the ultraviolet, visible, or infrared spectral region.

5. A process according to claim 1 in which the plasma is generated in a vortex produced by rapidly stirring the fluid in an enclosed reactor.

6. A process according to claim 1 which is carried out in an enclosed reactor, and in which the fluid is allowed to trickle by gravity down the side walls of said reactor.

7. A process according to claim 1 which is carried out in a cylindrical reactor into which the fluid is tangentially injected so as to cause a swirling thin film of said fluid on the reactor walls.

8. A process according to claim 1 which is carried out in an enclosed reactor into which reactor the fluid is sprayed so as to pass through the plasma.

9. A process for reducing the chemical oxygen demand of a wastewater, which comprises contacting said wastewater with an oxygen-containing gas in which a continuous plasma is generated by multiple pulses of focused laser radiation said plasma containing ultraviolet light, ions, x-ray, electrons, neutrons, and ozone, and rapidly transferring said plasma to said waste-water for a time sufficient to reduce said chemical oxygen demand.

10. A process according to claim 9 in which the chemical oxygen demand is due to the presence of organic substances resistant to biological degradation.

11. A process according to claim 10 in which the organic substances are halogenated compounds.

12. A process according to claim 9 wherein the laser radiation, before focusing, has a wavelength in the ultraviolet, visible, or infrared spectral region.

13. A process according to claim 9 wherein the laser radiation is obtained from a CO₂ laser of 9.2-10.6 μ

m wavelength.

14. A process according to claim 9 in which the plasma is generated in a vortex produced by rapidly stirring the fluid in an enclosed reactor.

15. A process according to claim 9 which is carried out in an enclosed reactor, and in which the fluid is allowed to trickle by gravity down the side walls of said reactor.

16. A process according to claim 9 which is carried out in a cylindrical reactor into which the fluid is tangentially injected so as to cause a swirling thin film of said fluid on the reactor walls.

17. A process according to claim 9 which is carried out in an enclosed reactor into which reactor the fluid is sprayed so as to pass through the plasma.