Abstract:
A compact inline filtering and sterilization system for liquids such as water for residential, commercial, hospital, laboratory, pharmaceutical, and other industrial use utilizes standard media filtration coupled with pulsed white light to sterilize. The unit uses a flow meter at the inlet to detect the flow of the liquid, and directs the untreated liquid first through a filter cartridge, and then through a pathway to be sterilized before exiting the device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority to Application Ser. No. 60/511,057, filed Oct. 14, 2003, which is incorporated herein by reference. 
     
    
     BACKGROUND  
       [0002]     This invention relates to the field of liquid filtering and deactivating pathogens.  
       SUMMARY  
       [0003]     A device as described here can be built as a compact inline filtering and sterilization system for liquids such as water for residential, commercial, hospital, laboratory, pharmaceutical, and other industrial use. The unit utilizes standard media filtration coupled with pulsed white light to sterilize. In preferred embodiments, the unit uses a flow meter at the inlet to detect the flow of the liquid, and directs the untreated liquid first through an “off the shelf” filter cartridge, and then directs the liquid through a precise pathway to be sterilized before exiting the device.  
         [0004]     The pulsing of intense white light is proven highly effective as an instantaneous sterilization technology to kill bacteria, viruses, spores, molds, fungi, and other microorganisms which either are not trapped by or have grown through a filtration system. Fouling of the flash lamp is minimized by the design of the precise and turbulent liquid pathway, creating a self cleaning effect to the lamp and treatment chamber surfaces. The system can be made in a relatively inexpensive manner. The pulses of white light are created by a flash lamp powered by a capacitor driven generator source which is mounted onto the filtration/treatment chamber body and installed in line to a water system for original construction or as a retrofit. A shut-off valve is provided at both the inlet and outlet to block the flow of the liquid during maintenance and filter replacement. The filter is removable without the need for special tools or detailed instruction. Other features and advantages will become apparent from the following detailed description, drawings, and claims.  
         [0005]     The objectives and advantages of this invention are to provide an affordable, compact, highly effective filtration and sterilization device, although some aspects of the invention would not necessarily require that all these advantages be met. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  is a partial cross-sectional, partial side view of an embodiment of an inline filtering system. 
     
    
     DETAILED DESCRIPTION  
       [0007]     In one embodiment, a filtration and sterilizing system  10  is mounted in line of a water (or other liquid) source  12  and has three main components: a body  14  that functions essentially as an adapter to the water line  12 , a full spectrum pulsed light lamp system  16  removably connected to the body unit; and a filtration housing  18  removably connected to body  14 .  
         [0008]     As shown in  FIG. 1 , body  14  has a water inlet  20  for untreated water and a water outlet  22  for treated water. The inlet and outlet can be co-linear to allow body  14  to be installed in line of a water line, either as part of new construction or as part of a retrofitted addition to an existing water line. A valve  24  can be provided on the inlet side to shut off the water for maintaining the system. Body  14  can be sized appropriately to accommodate different sized water lines.  
         [0009]     Full spectrum pulsed light lamp system  16  can be inserted into body  14  in such a manner that it can be removed as desired and needed, but is held rigidly when inserted, e.g., with a threaded compression nut to hold and seal it in place. The lamp  25  has power connections outside of the liquid path providing an intrinsically safe system and ease of maintenance. The lamp preferably only requires power input at one end, although it may be provided at both ends with some modifications, such as an electrical contact at the far end of the device. Lamp  25  is powered by a well defined lamp control and energy generator system  30  that would include a pulsed energy source consisting of capacitors to create high energy, short duration pulses, and timing circuitry for controlling the frequency of the pulses. The lamp is preferably straight and extends along a direction perpendicular to the water line, but it could have any suitable shape.  
         [0010]     Filtration unit  18  is removably connected to body  14 , preferably with threads  32  and a shoulder  34  that contacts and seals at the body  14 . The outer housing  42  of this unit can be formed of polymer or stainless steel and is cylindrical in shape, with a bore defined by a standard size filter cartridge. The inner treatment chamber  52  extending perpendicular to the water line for accepting lamp  25 , a protective quartz tube  56  and additional space to define a treatment chamber  36  in which water flows from bottom to top of the treatment chamber. Filtration unit  18  includes an annular filter  40  that can be a ribbon or wound filter and can be carbon-impregnated for removing chlorine and other undesired chemical impurities and particulates from the water.  
         [0011]     As shown in  FIG. 1 , water enters through the water inlet  12  and passes through an L-shaped conduit  44  into an outer annular region  46  between filter  40  and housing  42 . The water passes radially inwardly through the filter to an annular region  50  between the filter core  52  and the treatment chamber housing  58  and travels downwardly in the axial direction (upward and downward are used here only for reference, and there is no requirement that it be up or down against gravity). The water passes to a lowermost portion of unit  18  where there are openings  56  in the treatment chamber to allow the water to pass through  36  between the treatment chamber wall  58  and the lamp assembly  25 , which would typically have a quartz or glass housing  57  and a xenon flash lamp  25 . As the water passes through treatment chamber  58 , it is subjected to multiple pulses of full spectrum pulsed white light that will treat and sterilize the water. The inner surface of treatment chamber  57  facing lamp  25  is polished to provide a reflective surface yielding a compound treatment affect with each flash of pulsed light. The treated water then passes back out through water outlet  22  and to the water line. The size of the openings to the treatment chamber and the size of the treatment chamber can be set as desired, but are small enough to insure that the water receives a minimum number of pulses as it passes through the system.  
         [0012]     The system is provided with a flow meter  60  which senses the flow of water to instantaneously activate the flash lamp. Lamp control system  30  energizes the lamp to provide pulses. When the flow of water stops, the pulsed light lamp will turn off after a number of additional pulses.  
         [0013]     With this system, the water can be filtered and then treated with sterilizing pulses of intense white light before the water is dispensed. As used here, “white light” refers to the fact that the light has far UV, near UV, visible, and infrared components, e.g., 200 nm to 1000 nm. The design is such that the filter cartridges  46  are easily replaced by twisting off the housing  18  from the body  14 . A user could remove the filter and clean out the inside of the filtration housing conveniently. Separately, the treatment chamber  57  could be removed and the lamp&#39;s protective tube be cleaned or replaced without having to remove the filtration unit out of line.  
         [0014]     The size of the filtration unit is preferably on the order of several inches in diameter and about 6-18 inches in length, although larger or smaller sizes can be used, depending on the application. For household type uses, the system can preferably be mounted under a sink.  
         [0015]     Appropriate gaskets and seals, such as o-rings, can also be provided. Exemplary parameters include: pulse duration of 1-1000 microseconds measured at ⅓ peak valve; and energy per pulse of 1-2000 J.  
         [0016]     Having described embodiments herein, it should be ap0parent that modifications can be made without departing from the scope of the invention as defined by the appended claims. While this description has focused on the household use of water, this can be used for laboratory, pharmaceutical and other industrial liquid applications. While the light source is described as white light and while an exemplary wavelength range is provided, the type of light source and range of wavelengths can vary. Pulsed intense white light is believed useful for deactivating or sterilizing substantially all pathogens. Variations of the spectrum matrix within the lamp output may be used to target a specific or selected pathogen, or to kill or deactivate pathogens to a desired degree or threshold. In short, many of the benefits of the structure may be realized independent of the type of lamp or light that is used. While the lamp system is shown as removably connected to the body/adapter, it could be removably connected to the filter housing.