Method and apparatus for treating materials using electrodeless lamps

Abstract

The output wavelengths of an electrodeless lamp are controlled by passing a fluid over the surface of the lamp to control its temperature. The stabilized temperature prevents thermal runaway of the lamp and stabilizes the output wavelengths of the lamp. When the fluid passing over the lamp is water, the lamp can be used for sanitary treatment of the water. The treatment can be enhanced by shaping the electrodeless lamp to provide maximally effective water treatment.

1 . A water purification system for making potable water comprising:
 an electrodeless lamp excited by an energy source outside the lamp;   a layer of water that is to be treated flowing over the surface of the lamp to expose the water to the output radiation of the lamp; and   temperature control of the lamp using the flowing water to maintain the temperature of the lamp for controlling the wavelength of the lamp output to germicidally treat the water flowing over the lamp.   
     
     
         2 . The water purification system of  claim 1  wherein the energy source transmits energy to the electrodeless lamp passing through the layer of water that is streaming over the surface of the lamp. 
     
     
         3 . A water purification apparatus for actinically treating water for potability comprising:
 a tubular manifold having a closed end and an open end;   an electrodeless lamp having an annular shape with a central channel for passing water through the channel, the lamp mounted inside the manifold to allow water to pass over the outside of the lamp and through the channel of the lamp;   a header attached to the open end of the manifold having a water inlet, a water outlet and a seal at the end of the lamp adjacent the header to prevent water passing through the channel from mixing with water passing over the outside of the lamp, the apparatus allowing water to pass through the manifold such that it flows through both a space between the outside of the lamp and the inside of the manifold and through the channel of the lamp; and   an energizing source external to the lamp for exciting the lamp to radiate ultraviolet light.   
     
     
         4 . The apparatus of  claim 3  comprising using the apparatus for treating fluids other than water for purposes other than water purification. 
     
     
         5 . The apparatus of  claim 3  further comprising apparatus for controlling the temperature of the water and the flow rate of the water through the manifold to control the output wavelengths of radiation from the lamp. 
     
     
         6 . The apparatus of  claim 3  wherein the electrodeless lamp is filled with a mixture of gases comprising argon and mercury. 
     
     
         7 . The apparatus of  claim 3  wherein a controller is used to control the temperature of the fluid passing over the lamp in combination with the power input to the lamp to keep the lamp output at germicidal wavelengths. 
     
     
         8 . The apparatus of  claim 3  wherein the electrodeless lamp is regulated to provide output radiation at from about 240 nanometers wavelength to about 265 nanometers wavelength. 
     
     
         9 . The apparatus of  claim 3  maintaining the thickness of the space between the outside of the lamp and the inside of the manifold to less than about 0.25 inch.