Abstract:
A unitary water treatment system for filtering and purifying untreated water is disclosed that has a filtration compartment, a transfer compartment, and a purification compartment. The untreated water flows into the filtration compartment, then into the transfer compartment, and then into the purification compartment. A fill valve is provided at the inlet of the water treatment system; a transfer valve is provided between the transfer and purification compartments; and a drain valve is provide at the exit of the purification compartment. A UV lamp is placed in the center of the purification compartment to expose water trapped in the purification compartment to light in a desired frequency range to kill bacteria and viruses.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority benefit from U.S. provisional patent application 61/558,715 filed 11 Nov. 2011. 
     
    
     FIELD 
       [0002]    The present disclosure relates to a system and method for processing untreated water. 
       BACKGROUND 
       [0003]    A system and method by water can be both filtered and purified in a single unit is desired. 
       SUMMARY 
       [0004]    A unitary water treatment system for filtering and purifying untreated water is disclosed that has a filtration compartment, a transfer compartment, and a purification compartment. The untreated water flows into the filtration compartment, then into the transfer compartment, and then into the purification compartment. A fill valve is provided at the inlet of the water treatment system; a transfer valve is provided between the transfer and purification compartments; and a drain valve is provide at the exit of the purification compartment. A UV lamp is placed in the center of the purification compartment to expose water trapped in the purification compartment to light in a desired frequency range that kills bacteria and viruses. An opacity meter is provided in the top end of the filtration compartment. In some embodiments, an opacity meter is also provided at the bottom end of the filtration compartment. 
         [0005]    An electronic control unit is coupled to electronically controlled valves and opacity sensors. Based on input from the sensors and/or other information, electronically controlled valves can be controlled. 
         [0006]    Also disclosed is a method to control the water treatment system. A pressurized water supply is coupled to the inlet to the water treatment system. Untreated water flows into the filtration compartment that has a filtration media disposed therein. If the fill valve at the inlet of the filtration compartment is a float valve, the valve opens when the level of water in the filtration compartment is less than the set level. When the level hits the set level, the float valve closes. If the fill valve is electrically or mechanically actuated, the valve is opened to allow untreated water to flow into the filtration compartment. During this filling time, the transfer valve is closed. A self test of the opacity sensors may be performed when the filtration compartment is empty. If a fault is determined in either sensor, a fault code is set and operation of the system is discontinued. 
         [0007]    By opening the transfer valve, water flows into the purification compartment. By evaluating the opacity sensor signal, the time at which the sensor is covered with water can be determined so that the transfer valve can be commanded to close. The level of the opacity sensor signal is used to determine how long that UV lamp should be operated to properly kill bacteria and viruses in the water. After the UV lamp has been operated for this period of time, the lamp is turned off and the drain valve is opened to allow the treated water to drain out. A signal from the opacity sensor at the bottom of the purification compartment can be used to determine when the treated water has been emptied. The batch process may be repeated to obtain the desired amount of purified water. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic representation of a water filtration and purification system according to an embodiment of the disclosure; 
           [0009]      FIG. 2  is a cross section of the representation of the embodiment in  FIG. 1 ; and 
           [0010]      FIG. 3  is a flowchart of a method to operate the system of  FIGS. 1 and 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. Those of ordinary skill in the art may recognize similar applications or implementations whether or not explicitly described or illustrated. 
         [0012]    A water treatment system  10  is shown in  FIG. 1  in cross section. System  10  is provided untreated water  12  at entrance  14  in which a fill valve  16  is disposed leading to a filtration compartment  20 , which extends around the periphery of system  10 . Compartment  20  is enclosed by outer wall  18 . Fill valve  16  can be an electrically-operated valve such as a solenoid valve, a float valve which opens and closes based on the level of fluid in the compartment  20 , or a manually operated valve. Untreated water (level of water is shown at  22 ) is contained in compartment  20  as well as filtration media  24 . A wall  26  separates filtration compartment  20  from a transfer compartment  30  An opening in wall  26  near the bottom of system  10  has a screen  32  to contain filtration media  24  within compartment  20 . Transfer compartment  30  is separated from purification compartment  40  by a wall  46 . Wall  46  has an orifice into which a transfer valve  42  is disposed so that the transfer compartment  30  and purification compartment  40  can be selectively fluidly coupled. Purification compartment  40  has a UV lamp  44  centrally located. A reflective coating is provided on the inside surface of wall  46  so that UV light from UV lamp  44  is most effectively used. Also included is an orifice in the bottom of system  10  into which a drain valve  50  is disposed. When valve  50  is open, water  52  exits through exit tube  54 . A vent  56  is fluidly coupled to transfer compartment  30  so that when transfer compartment  30  or filtration compartment  20  are empty, air exits vent  56  to allow water to be admitted into compartments  20  and  30 . In the embodiment shown in  FIG. 1 , there is a gap in the wall near the top of system  10  between transfer compartment  30  and purification compartment  40 . In such an embodiment, vent valve  56  allows air to be removed and air to be introduced into purification compartment  40  such as when purified water is drained out of compartment  40 . If there is no such gap in wall  46 , an additional vent may be provided at the top of purification compartment  40 . 
         [0013]    A cross section that is perpendicular to the view shown in  FIG. 1  is illustrated in  FIG. 2 . The relative volumes of compartments  20 ,  30 , and  40  as implied by the area ratios in  FIG. 2  are just one example and are non-limiting to the present disclosure. Furthermore, the shapes of the compartments can be other than that shown in  FIG. 2 . It may be desirable, however, to have purification compartment  40  be of cylindrical shape with a cylindrical UV light  44  located centrally. With such a configuration, the path of the light is substantially constant from the source to the farthest reaches of the purification compartment. 
         [0014]    Referring again to  FIG. 1 , an electronic control unit (ECU)  70  is provided. An opacity sensor  58  is provided in a wall of the purification compartment  40 . The sensor has both a light source and a light sensor that causes the light from the light source reflects to the light sensor. The inside wall of purification compartment  40  has a reflective coating. The signal from light sensor provides an indication of the opacity of the medium in purification compartment  40 . The signal from opacity sensor  58  is highest when there purification compartment  40  is empty. Thus, opacity sensor  58  can be used to detect when water is in purification compartment  40  up to the level of sensor  58 . Sensor  58  is shown in  FIG. 1  as being below the water level  22  and as pointing toward transfer valve  42 . This is simply for illustration convenience. Instead, sensor  58  is placed at the desired fill level  22 . Furthermore, sensor  58  is placed such that is not in a line of sight with transfer valve  42  for two reasons: to avoid the incoming water during the filling process confounding the determination of compartment  40  being filled. In the embodiment in  FIG. 1 , an opacity sensor  60  is also provided near the bottom of purification compartment  40  to provide an indication that the tank is emptied. In an alternative, the time that is takes to empty purification compartment is determined and closing of drain valve  50  and repeating of the purification cycle is delayed until at least the time to empty the purification compartment has elapsed. 
         [0015]    As described above, valves  16 ,  42 , and  54  are mechanically actuated. Alternatively, they are controlled via ECU  70 . The dash-dot-dot lines in  FIG. 1  indicate an electrical connection between ECU  70  and the various sensors and actuators that are part of the system. 
         [0016]    A method by which system  10  can be controlled is illustrated in a flowchart in  FIG. 3 . The description below starts with system  10  empty, except for having filtration media in filtration compartment  20 . Further, valves  42  and  50  are closed. A pressurized water supply is connected to system  10  in block  100 . The pressurized water supply can be due to a pump from a water reservoir or gravity feed from a water reservoir that is located above system  10 . In block  102 , fill valve  16  is automatically open when fill valve  16  is a float valve. Alternatively, fill valve  16  is opened manually by an operator. In yet another alternative, fill valve  16  is commanded to open under control of ECU  70 . ECU  70  may be acting under control of an operator through control panel  72 . That is, when the pressurized water supply is provided to inlet  14 , the operator may depress a button on control panel  72  indicating that fill valve  16  should be opened. Or in another alternative, if there is a pressure sensor (not shown) on inlet  12 , ECU  70  may command opening of fill valve  16  based on a signal from the pressure sensor. When fill valve  16  is open, water enters through inlet  12  and fills filtration compartment  20  and transfer compartment  30 . Water is shutoff by closing fill valve  16  or by a float associated with fill valve  16 . 
         [0017]    Control passes to block  104  in which opacity sensors  58  and  60  are tested. If two such sensors are provided, as shown in  FIG. 1 , both sensors need to be working to pass control to block  108 . If either of sensors  58  or  60  fail a self test, control passes to block  106  in which the system is stopped and a fault code is set in ECU  70 . An error light on control panel  72  may be set to indicate the problem to the operator. When control passes to block  108 , transfer valve  42  is opened, either manually by an operator or under control by ECU  70 . Filtered water flows into purification compartment  40 . The signal from opacity sensor  58  changes when the air that is in purification compartment  40  is displaced by water. In block  110 , the change in signal is evaluated. When the signal changes, purification compartment  40  is full and control passes to block  112  in which transfer valve  112  is closed. 
         [0018]    In block  114 , a signal from opacity sensor  58  or  60  is used to determine opacity of the filtered water in purification compartment  40 . Time that is required for purification is determined based on the opacity of the water in purification compartment  40 . The UV lamp is turned on and operated for that purification time. Control then passes to block  116  in which drain valve  50  is opened and the purified water is released through exit tube  54 . 
         [0019]    Control passes to block  118  in which it is determined whether purification compartment  40  is empty. If not, control passes back to block  118 . If so, control passes back to block  102 . In one embodiment, exit tube  54  is coupled to a reservoir. If the reservoir becomes full, purification compartment  40  does not empty and the process is interrupted. In some embodiments, control panel  72  has a interrupt button to allow an operator to discontinue the operation of system  10 . 
         [0020]    In some embodiments, a light receptor on opacity sensor  58  or  60  may be used to detect the quality of light from UV lamp  44 . That is, UV lamp  44  is turned on briefly while purification compartment is empty. UV lamp intensity degrades over time. In such embodiments, the purification time is further based on the intensity of the light from UV lamp  44 . When UV lamp  44  intensity is too low to purify the water, a fault code in ECU  70  is set and possibly an error light is illuminated on control panel  72 . 
         [0021]    The filtration materials may be one of the following: sand, pure activated charcoal, silver-impregnanted activated charcoal, zeolite, bronze powder, aquarium wool, and coconut fibers, or a combination thereof. Such things as sand or coconut fibers might be readily available in some location in which purchased materials, such as activated charcoal, are not readily available. 
         [0022]    While the best mode has been described in detail with respect to particular embodiments, those familiar with the art will recognize various alternative designs and embodiments within the scope of the following claims. While various embodiments may have been described as providing advantages or being preferred over other embodiments with respect to one or more desired characteristics, as one skilled in the art is aware, one or more characteristics may be compromised to achieve desired system attributes, which depend on the specific application and implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. The embodiments described herein that are characterized as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications.