Abstract:
A water treatment apparatus provides treatment of water to remove, for example, hydrogen sulfide and iron, dissolved or dispersed in ground water. The system is provided with water from a conventional well and pump and includes a venturi-type aerating device which may be supplied air by a compressor. The air and water mixture are supplied to a first aerating tank through a spray nozzle which reduces the aerated water flow to a mist of fine droplets. A draw tube adjacent the bottom of the first tank provides the water to a treatment tank which is partially filled with a chemically active filtration media. The treatment tank is also equipped with a draw tube which draws off the treated water at the bottom of the tank and provides it to a third, deaerating tank wherein the air separates from the water and is purged to the atmosphere. Reduction of hydrogen sulfide content from 30 ppm to less than 5 ppm has been achieved.

Description:
CROSS REFERENCE TO CO-PENDING APPLICATION 
     This is a divisional of application Ser. No. 09/159,455 filed Sept. 24, 1998, now U.S. Pat. No. 6,103,108 granted Aug. 15, 2000. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to an apparatus for treating tap water and more specifically to for removing dissolved contaminants such as hydrogen sulfide (H 2 S) and iron from water and thereby improve the taste and potability of the water. 
     Apparatus for removing dissolved hydrogen sulfide and other undesirable dissolved minerals such as iron, is known in the art. For example, U.S. Pat. No. 4,430,228 discloses a process for removing dissolved iron from water utilizing an injector-mixer. The device draws air through a suction inlet into the water flow and includes a diffuser which assists air water mixing. The device also includes a by-pass flow control. 
     U.S. Pat. No. 5,354,459 to Smith discloses a complex apparatus for removing sulfur compounds from water. The apparatus includes a multiple tank arrangement wherein aeration, contaminant removal and deaeration occur. 
     U.S. Pat. No. 5,744,040, in which I am an named inventor, Leaches an apparatus and method for removing dissolved hydrogen sulfide from water which includes a unique manifold positioned within an open end of an atomizing tank. The manifold includes a channel in which air and water containing dissolved hydrogen sulfide are mixed. 
     Given my experience with these and many other water treatment systems, I have concluded that all suffer from certain shortcomings, some more serious than others. For example, some do not provide a necessary level of contaminant removal, others require frequent replacement of the filtration media and still others are overly complex and thus expensive. Accordingly, I have expended further effort to develop improvements in the art of water treatment. The following describes such improvements. 
     SUMMARY OF THE INVENTION 
     A water treatment apparatus provides treatment of water to remove, for example, hydrogen sulfide and iron, dissolved or dispersed in ground water. The system is provided with water from a conventional well and pump and includes a venturi-type aerating device which may be supplied air by a compressor. The air and water mixture are supplied to a first aerating tank through a spray nozzle which reduces the aerated water flow to a mist of fine droplets. A draw tube adjacent the bottom of the first tank provides the water to a treatment tank which is partially filled with a chemically active filtration media. The treatment tank is also equipped with a draw tube which draws off the treated water at the bottom of the tank and provides it to a third, deaerating tank wherein the air separates from the water and is purged to the atmosphere. Reduction of hydrogen sulfide content from 30 ppm to less than 5 ppm has been achieved. For increased water flows or removal of greater concentrations of hydrogen sulfide, the tanks may be doubled-up. 
     Thus, it is an object of the present invention to provide a water treatment system for removing dissolved hydrogen sulfide from water. 
     It is a further object of the present invention to provide an apparatus for removing hydrogen sulfide and other dissolved minerals such as iron from water. 
     It is a still further object of the present invention to provide an apparatus for removing hydrogen sulfide and other substances which may imbue the water with color or an unpleasant taste or odor which is simple to install, economical to use and inexpensive. 
     It is a still further object of the present invention to provide an improved apparatus for removing hydrogen sulfide and other dissolved substances from water which provides improved performance by reducing hydrogen sulfide content from 30 ppm or more to 5 ppm or less. 
     Further objects and advantages of the present invention will become apparent by reference to the following description of the preferred embodiment and appended drawings wherein like reference numbers refer to the same component, element or feature. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic elevational view of water treatment apparatus according to the present invention wherein three water treatment tanks are shown in cross section. 
     FIG. 2 is a full, sectional view of an air injector assembly incorporated in the present invention; 
     FIG. 3 is a full, sectional view of a vent control valve disposed in a third, deaerating tank of the present invention; 
     FIG. 4 is a bottom, plan view of a tank closure for the third, deaerating tank of the present invention; 
     FIG. 5 is a fragmentary side, elevational view of a tank closure and atomizing nozzle utilized in a first aerating tank of the present invention; 
     FIG. 6 is a diagrammatic view of the second, treatment tank and operate/regenerate valve assembly in the operate position; and 
     FIG. 7 is a diagrammatic view of the second, treatment tank and operate/regenerate valve assembly in the regenerate position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, a water treatment apparatus according to the present invention is illustrated and generally designated by the reference number  10 . 
     The apparatus  10  generally includes a plurality of treatment tanks which serially receive and condition tap (potable) water to remove contaminants. The tanks include a first, atomizing or aerating tank assembly  12 , a second, treatment tank assembly  14  and a third, daerating tank assembly  16 . Each of the tank assemblies  12 ,  14  and  16  will be described individually below. A control assembly  18  activates and deactivates the apparatus  10  as will also be described below. 
     The apparatus  10  includes an inlet pipe or conduit  22  which receives water from a conventional water supply system which typically will include a pump and may include a pressurized storage tank (both not illustrated). Water to be treated is supplied to the apparatus  10  through the pipe or conduit  22  at a nominal pressure of 40 to 50 p.s.i., and in any event, in the range of from 30 to 60 p.s.i. A solenoid valve  24  which may be of any construction suitable for water delivery systems operating at the above-recited pressure provide on/off control of the flow of water through the apparatus  10 . 
     The solenoid valve  24  is controlled by a pressure switch  26  which senses the pressure within the third, deaerating tank assembly  16 . The pressure switch  26  may be mounted atop the third, dederating tank assembly  16  or, preferably, achieve sensing communication with the interior of the third tank assembly  16  through a short length of pipe or flexible tubing  28 . The pressure switch  26  is configured to close on a pressure drop and open on a pressure increase. Although the open and close settings of the pressure switch  26  will necessarily be adjusted to conform with the operating and delivery pressures of the particular water supply system into which the apparatus  10  is installed, satisfactory operation has been achieved in many systems when the pressure switch  26  is adjusted to close at about 30 p.s.i. and open at about 50 p.s.i. It will be appreciated that when the pressure switch  26  closes, the solenoid valve  24  opens and supplies water from the conduit or pipe  22  to the apparatus  10  and when the pressure switch  26  opens, electrical energy to the solenoid valve  24  is terminated and it closes, terminating the flow of water into the treatment apparatus  10 . 
     Referring now to FIGS. 1 and 2, when the solenoid valve  24  is open, water is supplied to an air injector assembly  30 . The air injector assembly  30  includes a generally cylindrical housing  32  which defines a threaded inlet passageway  34 . Communicating with the threaded inlet passageway  34  is a first, by-pass passageway  36  and a second, air injection passageway  38 . Intersecting and extending generally radially from the by-pass passageway  36  is an internally threaded port  42 . The port  42  receives a complementary threaded set screw  44  which is aligned with, engages and is connected to a flow control gate or plug  46 . Upon clockwise or counter-clockwise rotation, the set screw  44  translates radially inwardly or outwardly, respectively, and advances or retracts the flow control gate or plug  46 . Preferably, the flow control plug  46  is circular and includes a peripheral groove  48  which receives an O-ring seal  52  therein. The O-ring  52  engages the housing  32  and provides a fluid-tight seal as will be readily appreciated. 
     Clockwise rotation of the set screw  44 , as noted, advances the plug  46  into the by-pass passageway  36 , restricting flow therethrough and vice versa. Increasing restriction of the flow through the by-p)ass passageway  36  thus increases flow through the air injection passageway  38  and vice versa. The appropriate position of the set screw  44  and thus of the plug  46  is that position which provides necessary flow through the air injection passageway  38  to achieve an appropriate quantity per volume of water of injected air to achieve appropriate aeration of the water flowing through the apparatus  10  as will be more fully described below. 
     As noted, the air injector assembly  30  also includes the second, air injection passageway  38  which define a first smaller diameter region  56 , a frusto-conical area  58  wherein the diameter of the air injection passageway  38  increases and a larger diameter region  62 . Extending radially from the frusto-conical region  58  is a venturi port  64 . The venturi port  64  communicates with a larger threaded region  66  which receives a check valve assembly  70 . The check valve assembly  70  includes an axial passageway  72  which receives a plunger  74  which is biased against an O-ring seal  76  by a coil compression spring  78 . When water flows through the air injection passageway  38  and specifically the frusto-conical region  66 , the pressure is reduced in the venturi port  64  and the atmospheric pressure and, more specifically, the pressure difference between that bearing upon the plunger  14  and within the venturi port  64  drives the plunger  74  open, thereby drawing air through the venturi port  64  into the air injection passageway  38 . 
     Typically, it has been found that while the venturi action of the air injector assembly  30  is significant, it does not provide sufficient injection of air into the water flowing through the air injection passageway  38  to achieve the necessary and desired level of water treatment. Accordingly, pressurized air is supplied to the air injection assembly  30  through a pipe or flexible hose  82 . The opposite end of the flexible pipe or hose  82  is connected to the output of and provided with air under pressure by a compressor  84 . The compressor  84  is activated when the pressure switch  26  is closed (low pressure) and deactivated when it is open (high pressure), as noted above. 
     It should be understood that if a source of clean compressed air at about 50 to 55 p.s.i. is available, the compressor  84  may be eliminated and, for example, a solenoid valve (not illustrated) controlled by the pressure switch  26  to provide compressed air to the air injector assembly  30  when the switch  26  is closed may be utilized. The compressor  84  is preferably a diaphragm type pump although any type of air compressor capable of delivering clean, oil free compressed air at a pressure of about 50 to 55 p.s.i. at a volume in the range of generally one to three cubic feet per minute or possibly more depending upon the volume of water to be treated during a given period of time has been found suitable. Again it should be understood that the pressure and flow rates recited herein are those encountered in a typical residential system for treating typically encountered concentrations of contaminants. As noted above, higher flow rates and higher concentrations of contaminants may require additional, i.e., multiple or larger tank assemblies  12 ,  14  and  16 . Additionally, certain installations may operate at higher or lower pressures requiring correspondingly higher or low operating pressures of, for example, the pressure switch  26  and the compressor  84 . 
     Water flow through the air injector assembly  30  and specifically the by-pass passageway  36  and the air injection passageway  38  then recombine at a threaded outlet port  86 . A nipple  88  is received within the outlet, port  86  and communicates with a first threaded can or closure  90  disposed upon the first, atomizing or aerating tank assembly  12 . 
     Turning then to FIGS. 1 and 5, the first aerating or atomizing tank assembly  12  includes the cap or closure  90  having exterior or male threads  92  which engage complementary threads  94  on a tank  96 . An O-ring seal  98  ensures sealing engagement between the closure  90  and the tank  96 . The tank  96  is preferably fiberglass reinforced plastic (FRP) although other materials are also suitable. The cap or closure  90  includes a right angle inlet passageway  102  having a first threaded region  104  into which the nipple  88  or similar fitting is secured. Tho nipple  88  couples the injector assembly  30  to the cap or closure  90 . Tire inlet passageway  102  also includes a threaded outlet port  106  which receives an atomizing nozzle  110 . The atomizing nozzle  110  includes a depending spiral atomizer  112  against which the water and air mixture impinges. The water and air mixture contacts the spiral atomizer  112  and its kinetic energy breaks the flow into fine droplets or mist. The spiral atomizer  112  preferably sprays a uniform full cone of atomized water and air mixture. The nozzle  110  may be like or similar to the HHSJ series of spray nozzles manufactured and sold under the Spiral Jet trademark. The nozzle  110  may be made of polyvinylohloride. 
     The interior of the first atomizing or aerating tank  96  is open or vacant, that is, it is not occupied by any media or any flow directing or redirecting elements. Rather, it provides an enclosed space wherein the air, and more particularly the oxygen, which has been injected into the water in the air injector assembly  30  may achieve intimate contact with the hydrogen sulfide, iron and other substances dissolved in the water. That is, it represents a chamber wherein intimate mixing and contact of the oxygen is achieved with the hydrogen sulfide, iron and other contaminants. With regard to the hydrogen sulfide, a sulfate is formed. 
     A draw tube  116  extends downward from the first cap or closure  90  to within an inch (2.54 cm) of the bottom of the first, aerating tank  96 . Water passing through the atomizing nozzle  110  thus falls to the bottom of the first, aerating tank  96  and is collected by the draw tube  116  and flows upwardly out of the first, aerating tank  96 . The first closure or cap  90  includes an outlet passageway  118  having a threaded region  122  which receives a complementary threaded portion of the draw tube  116  and also includes a threaded outlet port  104  which receives a nipple  126  which carries the partially treated water to the second, treatment tank assembly  14 . 
     Referring now to FIGS. 1,  6  and  7 , the second, water treatment tank assembly  14  includes a cap or closure  130  which is identical in all respects to the cap or closure of the first tank assembly  12 . That is, it includes external or male threads  132  which are complementary to and engage female threads  134  on the mouth of a second, treatment tank  136 . The second, treatment tank is also preferably made of fiberglass reinforced plastic. An O-ring  138  provides a suitable seal between the tank  136  and the closure  130 . The second cap or closure  130  includes an inlet passageway  140  having a threaded portion  142  which receives a complementary threaded portion of a nipple  144  and a threaded outlet port  146  which may simply open into the interior of the second treatment tank  136  or receive a short nipple  148 . The cap or closure  130  also includes an outlet passageway  150  having a threaded portion  152  which receives a complimentarily threaded end portion of a draw tube  154 . At the lower terminus of the draw tube  154  is a slotted riser or sieve screen  156  having openings or passageways preferably smaller than 0.010″ which permit the passage of water but inhibit the passage of particulate material. The outlet passageway  150  of the second cap or closure  130  also includes a threaded region  158  which receives an outlet nipple  160 . 
     The middle region of the treatment tank  136  is filled with a treatment media  162  containing manganese dioxide. Many different materials are suitable such as green sand, Pyrolox manufactured by Texas Mining and Minerals or Filox manufactured by the Matt-son Company. Selection of one of the foregoing treatment media  162  or other media containing manganese dioxide will be guided by considerations of optimum performance in view of the specific water contaminant or combination of contaminants to be removed. A lower region of the treatment tank  136  is filled with a coarse media  164  such as No. 8 garnet. The treatment media  162  forms a loose bond with the hydrogen sulfide molecules and the iron and manganese cations and the water exits the second treatment tank through the draw tube  156  substantially free of the targeted contaminants such as hydrogen sulfide and iron. 
     Associated with the second, treatment tank assembly  14  is an operate/regeriurate control assembly  170  sometimes referred to as a backwash control. The control assembly  170  may be like or similar to the model  163  manufactured by Osmonics/Autotrol Company. The operate/regenerate assembly  170  preferably includes a twenty-four hour timer  172  which controls a multi-port valve  174  having a rotatable or translatable spool or spindle  176 . The timer  172  is configured to reposition the spool or spindle  176  from the position illustrated in FIG. 6 to that illustrated in FIG. 7 for a period of time sufficient to regenerate the treatment media  162  during the night or early morning hours when water use is at a minimum. Thus, the timer may be set to activate the valve spool or spindle  176  at 3:00 a.m. and rotate it from the position illustrated in FIG. 6 to that illustrated in FIG.  7  and then, a fixed period of time later, from 15 to 30 minutes, or more or less depending on the system parameters and usages, return the valve spool or spindle  176  to the position illustrated in FIG.  6 . 
     The valve body  174  includes an operating inlet port  180  which is coupled to the nipple  126  from the first, aerating tank assembly  12 . Adjacent the operating inlet port  180  is an operating outlet port  182  which is coupled to a nipple  184  which leads to the third, deaerating tank assembly  16 . A first tank port  186  communicates with the nipple  144  which is received within the threaded portion  142  of the inlet passageway  140  of the second cap or closure  130 . Similarly, the valve body  174  defines a second tank port  190  which is coupled to the threaded portion  158  of the outlet passageway  150  of the second cap or closure  130  by the nipple  160 . The valve body  174  further defines a regenerate inlet port  194  Which is in communication with a supply of water through a line  196 . Finally, the valve body  174  defines a regenerate outlet port  198  which is in communication with an outlet drain line  202 . 
     When the valve spindle or spool  176  is in the position illustrated in FIG. 6, the flow of aerated water from the nipple  126  enters the operating inlet port  180  and moves through a first passageway  206  in the spindle or spool  116 . The passageway connects the port  180  with the port  186  and the aerated water thus moves through the nipple  144 , through the inlet passageway  140  and into the interior of the second, treatment tank  136 . The aerated water passes through the treatment media  162  where, as noted, the sulfate forms loose bonds with the manganese dioxide treatment media  162 . The water then passes through the coarse media  164 , through the slotted sieve  156 , up the draw tube  154 , out the outlet passageway  150 , through the nipple  160  and into the second tank port  190 . At this time, a second passageway  208  in the spindle or spool  176  connects the second tank port  190  with the operating outlet port  182  and the water flows out the nipple  184 . 
     During the regenerate cycle when the valve spindle or spool  176  has rotated 180°, it is positioned as illustrated in FIG.  1 . Now, flow through the nipple  126 , the ports  180  and  162  and the nipple  184  is terminated. A flow of water enters the nipple  196 , like regenerate inlet port  194 , the first passageway  206  and exits the valve body  174  through the second tank port  190  and the nipple  160 . This rinse or backwash water then passes through the outlet passageway  150 , the draw tube  154 , through the coarse media  164  and upward through the treatment media  162 . This flow strips the sulfate as well as other contaminants from the treatment media  162  and they flow with the water out the inlet passageway  140 , through the nipple  144 , through the first tank port  186 , through the second passageway  208  in the valvo spindle or spool  116 , through the regenerate outlet port  198  and out the drain line  202 . Thus, it will be apparent that depending upon the position of the valve spindle or spool  176 , the assembly  170  fully and automatically selects either the operate mode of the water treatment apparatus  10  as illustrated in FIG. 6 or the regenerate or backwash mode of the water treatment apparatus  10  as illustrated in FIG.  7 . It may also be desirable to provide a third, purge mode of operation which comprehends providing a short period of downward (operating) flow through the treatment media  162  and coarse media  164  which is then provided to the drain line  202  to completely clear the second, treatment tank  136  of all backwash water. 
     Referring now to FIGS. 1 and 4, the third, deaerting tank assembly  16  will now be described. The third, deaerating tank assembly  16  includes a third cap or closure  220  having a threaded portion  222  which is received within a complementary threaded portion  224  of a third tank  226 . The third tank  226  is also preferably made of fiberglass reinforced plastic. An O-ring seal  228  achieves a seal between these components. The third cap or closure  220  includes an inlet port or passageway  232  having threads  234  which are complementary configured and receive the threads on the end of the nipple  184 . The inlet passageway  232  communicates with the interior of the third deaseratiing tank  226 . An outlet passageway  236  includes a threaded region  238  which receives the threaded terminal portion of a draw tube  242 . The draw tube  242  extends approximately to the bottom of the interior of the third, deaerating tank  226 . The outlet passage  236  also includes a threaded region  244  into which is received a complementary threaded end portion or a tube or pipe  246  which delivers treated water to the home or building water distribution system (not illustrated). The third cap or closure  220  also includes a through passageway or pressure port  248  which provides communication between the interior of the third, deaerating tank  226  and the pressure switch  26  through the pipe or tubing  28 . Thus, it will be appreciated that the pressure switch  26  monitors, on a continuous basis, the pressure within the third tank  226 . 
     Lastly, the third cap or closure  220  on the deaerating tank assembly  16  includes a vent port  252 . Preferably, a small, typically flexible, vent line or tube  254  will be utilized and it extend from the vent port  252  to the exterior of the home or building such that any unpleasant odors are released outside rather than inside the building. Disposed within the interior of the third tank  226  and installed in a threaded region  256  of the vent port  252  is a vent control assembly  260 . 
     Referring now to FIGS. 1 and 3, the vent control assembly  260  includes a cylindrical housing  262  which defines an open interior region  264  in communication with the vent port  252  through a nipple  266  or tube preferably Integrally formed with the vent control assembly  260 . At the lower terminus of the body  262  is a stop or plate  268  having a plurality of through apertures  272 . The apertures  272  provide communication between the interior of the tank  26  and the interior  264  of the body  262 . Disposed within the interior  264  is a cylindrical float  274 . The float  274  is buoyant in water and as water rises and falls in the interior of the tank  226 , the apertures  272  allow water to rise and fall within the interior  264  of the body  262 . The float  274  includes a resilient valve plug or piston  276  at its upper terminus. A baffle  278  extends across an upper portion of the chamber  264  and define a single through passageway  288  having a diameter of less than about 0.01625 inch and preferably about 0.010 inch. It will thus be readily appreciated that as the float  274  is raised within the internal chamber  264  such that the valve plug  276  engages the baffle  278 , the passageway  282  is closed. Contrariwise, when the water level within the interior of the third deaerating tank  226  drop sufficiently, the float  274  falls and the port or passageway  282  is opened, thereby allowing air to escape from the interior of the third tank  226  and maintain a desired balance between the volume of the third tank  226  occupied by air and the volume of the third tank  226  occupied by water. 
     The foregoing disclosure is the best mode devised by the inventor for practicing this invention. It is apparent, however, that apparatus incorporating modifications and variations will be obvious to one skilled in the art of water treatment. Inasmuch as the so foregoing disclosure presenting the best mode contemplated by the inventor for carrying out the invention and is intended to enable any person skilled in the pertinent art to practice this invention, it should not be construed to be limited thereby but should be construed to include such aforementioned obvious variations and be limited only by the spirit and scope of the following claims.