Abstract:
A method of producing a hydrated firefighting composition includes providing a fire fighting gel concentrate at a predetermined gel flow rate, providing a hydrating liquid at a predetermined liquid flow rate, controlling the gel flow rate and the liquid flow rate based on one another, and combining the firefighting gel concentrate and the hydrated liquid to produce a hydrated firefighting composition.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to U.S. Provisional Application Ser. No. 60/660,121, filed Mar. 9, 2005, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates generally to firefighting systems and more particularly to a method and apparatus to facilitate firefighting.  
         [0003]     Fires can only exist if three elements are present: heat, fuel, and oxygen. In wildland firefighting, fires are extinguished by removing fuel from the fire. Generally, a fire extinguishing agent is applied from the air to coat unburned fuels on the ground with a material generically called Long Term Retardant.  
         [0004]     At least one known Long Term Retardant includes a powdered material and/or a concentrated base material that is mixed with water to a desired consistency. The known Long Term Retardant is then stored in tanks for loading on the aircraft. The aircraft then drops the Long Term Retardant on unburned fuels in the path of an advancing wildland fire with the intent of starving the fire of fuel.  
         [0005]     More specifically, at least one known Long Term Retardant includes a clay-based material that, when mixed with water, forms a slurry. When the clay-based Long Term Retardant is dropped from an aircraft, it coats ground fuels with a film of wet fire clay that dries very quickly. If the fire reaches the coated fuels before the Long Term Retardant dries, it is effective. However, if the clay-based Long Term Retardant dries before it coats the ground fuel, the clay-based Long Term Retardant is only marginally effective in resisting direct flame impingement.  
         [0006]     Moreover, at least one known Long Term Retardant includes a gel concentrate, also referred to as a “water enhancer”, that absorbs water molecules and holds them in suspension inside a polymer bubble. When used as a Long Term Retardant and dropped from aircraft, the poly-drops of water attach themselves to unburned fuels. However, gel concentrates do not readily mix with water. More specifically, when known gel concentrates are mixed with water, a phenomenon called gel-block occurs, resulting in a heterogeneous mixture. Therefore, severe agitation must be instituted to complete the mixing process. The known gel-based Long Term Retardant is then stored for up to 24 hours while maximum hydration is achieved. If underhydrated gel-based Long Term Retardant is applied to wildland fires it may not perform as expected and additionally could create an environmental remediation problem.  
       BRIEF DESCRIPTION OF THE INVENTION  
       [0007]     In one aspect, a method is provided of producing a hydrated firefighting composition that comprises providing a fire fighting gel concentrate at a predetermined gel flow rate, providing a hydrating liquid at a predetermined liquid flow rate, controlling one of the gel flow rate and the liquid flow rate based on the other of the gel flow rate and the liquid flow rate, and combining the firefighting gel concentrate and the hydrated liquid to produce a hydrated firefighting composition.  
         [0008]     In another aspect, a system is provided that includes a blending stage having an inlet and a discharge. A hydrating liquid and a gel concentrate enter the blending stage at the inlet as a heterogeneous solution and continuously flow from the inlet to the discharge without storage in the blending stage.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is an exemplary system for producing a hydrated firefighting composition;  
         [0010]      FIG. 2  is a schematic illustration of a mixing station;  
         [0011]      FIG. 3  is a schematic illustration of an optional mixing station; and  
         [0012]      FIG. 4  is a second exemplary system for producing a hydrated firefighting composition. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]      FIG. 1  is a system  10  for producing a hydrated firefighting composition  12 . System  10  includes a first storage unit  20  and a first pumping module  22  coupled in flow communication with the first storage unit  20 . A second pumping module  32  is coupled in flow communication with a second storage unit  30 . A third pumping module  42  is coupled in flow communication with a third storage unit  40 . System  10  also includes a manifold  50  that is coupled in flow communication with first pumping module  22 , second pumping module  32 , and third pumping module  42 , respectively, and a blending and/or mixing stage  52  that is coupled in flow communication with manifold  50 .  
         [0014]     First storage unit  20  is utilized to store a predetermined quantity of firefighting gel concentrate  60 , second storage unit  30  is utilized to store a predetermined quantity of a hydrating fluid  62 , and third storage unit  40  is utilized to store a predetermined quantity of colorant  64 .  
         [0015]     First pumping module  22  includes a pump  70  (for example, but not limited to, a variable speed pump) having an inlet or suction side  72  that is coupled in flow communication with first storage unit  20 , an outlet or discharge side  74 , that is coupled in flow communication with manifold  50 , and a control system  76  that may be utilized to vary the output of pump  70 . The pump  70  channels firefighting gel concentrate  60  from first storage unit  20  to manifold  50 .  
         [0016]     Second pumping module  32  includes a pump  80  having an inlet or suction side  82  that is coupled in flow communication with second storage unit  30 , an outlet or discharge side  84 , that is coupled in flow communication with manifold  50 , and a control system  86  that may be utilized to vary the output of pump  80 . The pump  80  channels hydrating fluid  62  from second storage unit  30  to manifold  50 .  
         [0017]     Third pumping module  42  includes a pump  90  having an inlet, or suction side  92  that is coupled in flow communication with third storage unit  40 , an outlet, or discharge side  94 , that is coupled in flow communication with manifold  50 , and a control system  96  that may be utilized to vary the output of pump  90 . The pump  90  channels colorant  64  from third storage unit  40  to manifold  50 . Although only a single colorant storage unit  40  is shown, it should be realized that system  10  may include a plurality of colorant storage units  40 , each including a different colorant  64 , to facilitate injecting a plurality of colorants, either simultaneously or separately, into manifold  50 .  
         [0018]     Each control system  76 ,  86 , and  96  may include a respective computing module  100 ,  102 , and  104 , that is configured to receive at least one input and vary the output of the respective pump  70 ,  80  and  90  based on the received input. In the exemplary embodiment, computing modules  100 ,  102 , and  104 , are each configured to activate and/or deactivate respective pumps  70 ,  80 , and/or  90 . Optionally, the flows of water, colorant and gel may be controlled by opening, closing, and/or varying a valve, orifice, or the like. The computing modules  100 ,  102 , and  104  execute instructions stored in firmware (not shown). Computing modules  100 ,  102 , and  104  are each programmed to perform functions described herein. As used herein, the term computing module is not limited to just those integrated circuits referred to in the art as computers, but broadly refers to, microprocessors, microcontrollers, microcomputers, programmable logic controllers, application specific integrated circuits, and other programmable circuits, and these terms are used interchangeably herein.  
         [0019]     System  10  also includes a mixing station  110  to facilitate mixing and/or blending materials discharged from first storage unit  20 , second storage unit  30  and/or third storage unit  40  to produce a fully hydrated firefighting composition  12 . More specifically, the water is encapsulated by the gel to facilitate reducing evaporation. The term “fully hydrated” as used herein is defined as when at least 85% of the hydrating liquid is encapsulated in the gel concentrate. As such, when 98% of the hydrating liquid is encapsulated in the gel concentrate, the composition is fully hydrated.  
         [0020]     In one embodiment, shown in  FIG. 2 , mixing station  110  includes a static mixer  52  having an inlet  114  coupled in flow communication with manifold  50  and an outlet  116 . Static mixer  52  includes a series of geometric mixing elements and/or baffles  118  that are fixed within an outer casing  120 . In operation, static mixer  52  utilizes the energy of the flow stream to mix two or more fluids channeled therethrough. Although the exemplary embodiment includes a static mixer  52  to facilitate mixing the fluids channeled therethrough, it should be realized that various other devices such as a dynamic mixer, shown in  FIG. 3 , i.e. a spinning propeller in a hollow tube, may also be utilized to mix the various fluids.  
         [0021]     Optionally, mixing station  110  includes a dynamic static mixer  53  shown in  FIG. 3 , having an inlet  15  coupled in flow communication with manifold  50  and an outlet  117 . Static mixer  53  includes at least one movable mixing element  119 , such as an auger for example that are coupled within an outer casing  121 . In operation, static mixer  53  utilizes mixing elements  119  to mix two or more fluids channeled therethrough.  
         [0022]     Referring again to  FIG. 1 , system  10  also includes a plurality of sensing elements and/or transducers to facilitate monitoring and/or controlling the flowrate and/or pressure of the materials discharged from storage units  20 ,  30 , and  40 , respectively. Specifically, a first pressure sensor  150 , a first flow sensor  152 , and a first temperature sensor  154  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from first pumping module  22 . A second pressure sensor  160 , a second flow sensor  162 , and a second temperature sensor  164  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from second pumping module  32 . A third pressure sensor  170 , a third flow sensor  172 , and a third temperature sensor  174  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from third pumping module  22 .  
         [0023]     System  10  also includes a first regulating assembly  180  that, in the exemplary embodiment, is coupled to a control panel  182 . The regulating assembly  180  controls the quantity of materials discharged from first pumping module  22 , Optionally, the first regulating assembly  180  may be coupled to first pumping module  22 . The first regulating assembly  180  may constitute a manual valve that transmits a signal to computing module  100  to facilitate regulating the quantity of firefighting gel concentrate  60  that is discharged from first pumping module  22  into manifold  50  and then mixed with hydrating fluid  62  and/or colorant  64 . In another embodiment, first regulating assembly  180  may be an electronic input device configured to receive an operator input indicative of the desired quantity of firefighting gel concentrate  60  to be discharged from first pumping module  22  into manifold  50 .  
         [0024]     A second regulating assembly  190  controls the quantity of materials discharged from third pumping module  42 . The second regulating assembly  190  is coupled to control panel  182 . Optionally, second regulating assembly  190  may be coupled to third pumping module  42 . The second regulating assembly  190  may be a manual valve that transmits a signal to computing module  104  to facilitate regulating the quantity of colorant  64  that is discharged from third pumping module  42  into manifold  50  and then mixed with hydrating fluid  62  and/or firefighting gel concentrate  60 . In another embodiment, second regulating assembly  190  may be an electronic input device configured to receive an operator input indicative of the desired quantity of colorant  64  to be discharged from third pumping module  42  into manifold  50 .  
         [0025]     A portable platform  200  is provided that permits system  10  to be transported and/or moved to various locations. For example, system  10  may be coupled to a trailer assembly such that system  10  can be transported to an aircraft, for example, wherein system  10  can operated to facilitate discharging hydrated firefighting composition  12  into the waiting aircraft. Additionally, portable platform  200  may be either permanently or temporarily installed on, or coupled to, a vehicle and driven to the aircraft.  
         [0026]     In operation, first storage unit  20  is filled to a predetermined capacity with a firefighting gel concentrate  60 . In the exemplary embodiment, firefighting gel concentrate  60  is a polymer gel concentrate such as, but not limited to, AFG Firewall™ distributed by Ansul Canada Ltd. The first storage unit  20  may be selectively sized to store several gallons of firefighting gel concentrate  60 . Second storage unit  30  is filled to a predetermined capacity with a hydrating fluid  62 , such as fresh water. In the exemplary embodiment, second storage unit  30  is selectively sized to store several gallons of freshwater. Third storage unit  40  is filled to a predetermined capacity with a colorant  64 . In the exemplary embodiment, colorant  64  is one of a known colorant dyes that can be utilized to change the color of hydrated firefighting composition  12  from a first, or uncolored shade, to a second or colorized shade. Color enables an operator to visually observe surfaces in which hydrated firefighting composition  12  has been previously applied. As stated previously herein, colorant  64  may be selected from a wide variety of colors that are pre-selected based on the terrain in which firefighting composition  12  is to be applied.  
         [0027]     System  10  is then transported to a receiving vehicle (not shown) and is coupled to the receiving vehicle using a hose for example. A discharge valve  202  is then opened to discharge hydrated firefighting composition  12  to the receiving vehicle.  
         [0028]     In operation, system  10  is configurable to produce a fully hydrated firefighting composition  12  that includes a predetermined percentage of firefighting gel concentrate  60 , a predetermined percentage of hydrating fluid  62 , and a predetermined percentage of colorant  64 . Accordingly, to operate system  10 , the operator inputs a desired firefighting gel concentration setting into computing module  100 . For example, the operator may select a gel concentration that, in the exemplary embodiment, is between approximately 0.5% and approximately 3.0% of the total volume of firefighting composition  12  produced by system  10 . Optionally, the operator may select a gel concentration that is greater than 3% of the total volume of firefighting composition  12  produced by system  10 . Additionally, the operator may select a colorant  64  concentration that, in the exemplary embodiment, is between approximately 0.1% and approximately 1.0% of the total volume of firefighting composition  12  produced by system  10 . Optionally, the operator may select a colorant  64  concentration that is greater than 1% of the total volume of firefighting composition  12  produced by system  10 .  
         [0029]     After the selected concentrations of gel concentrate  60  and colorant  64  have been entered, system  10  is initialized to produce hydrated firefighting composition  12 . More specifically, second pump  80  is initialized to discharge hydrating fluid  62  from storage unit  30  into manifold  50 . In the exemplary embodiment, second pump  80  is configured to discharge hydrating fluid  62  into manifold  50  at approximately four hundred gallons per minute (GPM). Computing modules  100  and  104  each receive inputs from pressure sensor  160 , flow sensor  162 , and temperature sensor  164 . Computing module  104  then energizes pump  90  to facilitate colorant  64  into manifold  50  based on either the temperature, pressure, or flowrate of hydrating fluid  62  being discharged through manifold  50 . For example, if second pump  80  is discharging approximately four-hundred GPM through manifold  50 , and an operator has selected a fully hydrated firefighting composition  12  that includes approximately 1.0% colorant  64  per volume produced, computing module  104  will energize pump  90  such that pump  90  discharges approximately four GPM of colorant  64  into manifold  50 . Additionally, if the operator has selected a fully hydrated firefighting composition  12  that includes approximately 3.0% gel concentrate  60  per volume of fully hydrated firefighting composition  12  produced, computing module  100  will energize pump  70  such that pump  70  discharges approximately twelve GPM of gel concentrate  60  into manifold  50 .  
         [0030]     As explained previously herein, gel concentrate  60 , hydrating fluid  62 , and colorant  64  initially form a heterogeneous composition within manifold  50 . The heterogeneous composition is then channeled through manifold  50  and into static mixer  52  wherein the heterogeneous composition is mixed and/or blended to form fully hydrated firefighting composition  12 . More specifically, static mixer  52  facilitates blending or mixing the heterogeneous composition without storage within static mixer  52 . Thus, the heterogeneous composition is channeled through static mixer input  114 , mixed within static mixer  52  without storage, and discharged from static mixer discharge  116  as a fully blended, homogeneous firefighting composition  12  that is also fully hydrated when discharged from static mixer  52 .  
         [0031]     The term homogeneous is not limited to an ideal solution or mixture, but instead, as used throughout, is intended to include substantially homogeneous compositions. Moreover, a gel composition shall be fully hydrated so long as the viscosity of the gel composition remains, for a predetermined period of time, within a desired or operating range usable for its intended purpose. By way of example only, a gel composition shall be considered fully hydrated if the viscosity does not substantially vary by more than 15% within a six hour period, vary by more than 20% within a twelve hour period, or vary by more than 25% within a twenty-four hour period, following discharge of the gel composition from the system  10 .  
         [0032]      FIG. 4  is another exemplary system  300  for producing a hydrated firefighting composition  12 . System  300  is substantially similar to system  10 , shown in  FIG. 1 , and components in system  300  that are identical to components of system  10  are identified in  FIG. 4  using the same reference numerals used in  FIG. 1 . Accordingly, system  300  includes a first storage unit  20  and first pumping module  22  coupled in flow communication with the first storage unit  20 . A second pumping module  32  is coupled in flow communication with a second storage unit  30 . A third pumping module  42  is coupled in flow communication with a third storage unit  40 . System  300  also includes a manifold  50  that is coupled in flow communication with first pumping module  22 , second pumping module  32 , and third pumping module  42 , respectively, and a blending and/or mixing stage  52  that is coupled in flow communication with manifold  50 . First storage unit  20  is utilized to store a predetermined quantity of firefighting gel concentrate  60 , second storage unit  30  is utilized to store a predetermined quantity of a hydrating fluid  62 , and third storage unit  40  is utilized to store a predetermined quantity of colorant  64 .  
         [0033]     First pumping module  22  includes a pump  70  having an inlet or suction side  72  that is coupled in flow communication with first storage unit  20 , an outlet or discharge side  74 , that is coupled in flow communication with manifold  50 , and a control system  76  that is utilized to vary the output of pump  70 . The pump  70  is sized to channel firefighting gel concentrate  60  from first storage unit  20  to manifold  50 .  
         [0034]     Second pumping module  32  includes a pump  80  having an inlet or suction side  82  that is coupled in flow communication with second storage unit  30 , an outlet or discharge side  84 , that is coupled in flow communication with manifold  50 , and a control system  86  that is utilized to vary the output of pump  80 . The pump  80  is sized to channel hydrating fluid  62  from second storage unit  30  to manifold  50 .  
         [0035]     Third pumping module  42  includes a pump  90  having an inlet, or suction side  92  that is coupled in flow communication with third storage unit  40 , an outlet, or discharge side  94 , that is coupled in flow communication with manifold  50 , and a control system  96  that is utilized to vary the output of pump  90 . The pump  90  is sized to channel colorant  64  from third storage unit  40  to manifold  50 . Although only a single colorant storage unit  40  is shown, it should be realized that system  300  may include a plurality of colorant storage units  40 , each including a different colorant  64 , to facilitate injecting a plurality of colorants, either simultaneously or separately, into manifold  50 .  
         [0036]     System  300  also includes a single computing module  310  that is configured to receive at least one input and to vary the output of at least one of pumps  70 ,  80  and  90  based on the received input. The computing module  310  either activates or deactivates a respective pump  70 ,  80 , and/or  90  based on the received input from a keyboard  312 , for example. Computing module  310  may execute instructions stored in firmware (not shown). Computing module  310  is programmed to perform functions described herein. As used herein, the term computing module is not limited to just those integrated circuits referred to in the art as computers, but broadly refers to, microprocessors, microcontrollers, microcomputers, programmable logic controllers, application specific integrated circuits, and other programmable circuits, and these terms are used interchangeably herein.  
         [0037]     System  300  also includes a mixing station  110  to facilitate mixing and/or blending materials discharged from first storage unit  20 , second storage unit  30  and/or third storage unit  40  to produce a fully hydrated firefighting composition  12 . The mixing station  110  includes a static mixer  52  having an inlet  114  coupled in flow communication with manifold  50  and an outlet  116 . Static mixer  52  includes a series of geometric mixing elements and/or baffles  118  that are fixed within an outer casing  120 . In operation, static mixer  52  utilizes the energy of the flow stream to mix two or more fluids channeled therethrough.  
         [0038]     System  300  also includes a plurality of sensing elements and/or transducers to facilitate monitoring and/or controlling the flowrate and/or pressure of the materials discharged from storage units  20 ,  30 , and  40 , respectively. Specifically, a first pressure sensor  150 , a first flow sensor  152 , and a first temperature sensor  154  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from first pumping module  22 . A second pressure sensor  160 , a second flow sensor  162 , and a second temperature sensor  164  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from second pumping module  32 . A third pressure sensor  170 , a third flow sensor  172 , and a third temperature sensor  174  are configured to sense the pressure, flow, and temperature, respectively, of the material discharged from third pumping module  22 .  
         [0039]     In operation, first storage unit  20  is filled to a predetermined capacity with a firefighting gel concentrate  60 . In the exemplary embodiment, firefighting gel concentrate  60  is a polymer gel concentrate such as, but not limited to, AFG Firewall™ distributed by Ansul Canada. The first storage unit  20  may be selectively sized to store several gallons of firefighting gel concentrate  60 . Second storage unit  30  is filled to a predetermined capacity with a hydrating fluid  62 , such as fresh water. In the exemplary embodiment, second storage unit  30  is selectively sized to store several gallons of freshwater. Third storage unit  40  is filled to a predetermined capacity with a colorant  64 . In the exemplary embodiment, colorant  64  is one of a known colorant dyes that can be utilized change the color of hydrated firefighting composition  12  from a first, or uncolored shade, to a second or colorized shade.  
         [0040]     System  300  is configurable to produce a fully hydrated firefighting composition  12  that includes a predetermined percentage of firefighting gel concentrate  60 , a predetermined percentage of hydrating fluid  62 , and a predetermined percentage of colorant  64 . Accordingly, to operate system  300 , the operator inputs a desired firefighting gel concentration setting into computing module  310 . For example, the operator may select a gel concentration that, in the exemplary embodiment, is between approximately 0.5% and approximately 3.0% of the total volume of firefighting composition  12  produced by system  300 . Additionally, the operator may select a colorant  64  concentration that, in the exemplary embodiment, is between approximately 0.1% and approximately 1.0% of the total volume of firefighting composition  12  produced by system  300 .  
         [0041]     After the selected concentrations of gel concentrate  60  and colorant  64  have been entered, system  300  is initialized to produce hydrated firefighting composition  12 . More specifically, second pump  80  is initialized to discharge hydrating fluid  62  from storage unit  30  into manifold  50 . In the exemplary embodiment, second pump  80  is configured to discharge hydrating fluid  62  into manifold  50  at approximately four hundred gallons per minute. Computing module  310  receives inputs from pressure sensor  160 , flow sensor  162 , and temperature sensor  164 . Computing module  310  then energizes pump  90  to facilitate colorant  64  into manifold  50  based on either the temperature, pressure, or flowrate of hydrating fluid  62  being discharged through manifold  50 . For example, if second pump  80  is discharging approximately four-hundred GPM through manifold  50 , and an operator has selected a fully hydrated firefighting composition  12  that includes approximately 1.0% colorant  64  per volume produced, computing module  310  will energize pump  90  such that pump  90  discharges approximately four GPM of colorant  64  into manifold  50 . Additionally, if the operator has selected a fully hydrated firefighting composition  12  that includes approximately 3.0% gel concentrate  60  per volume of fully hydrated firefighting composition  12  produced, computing module  310  will energize pump  70  such that pump  70  discharges approximately twelve GPM of gel concentrate  60  into manifold  50 .  
         [0042]     As explained previously herein, gel concentrate  60 , hydrating fluid  62 , and colorant  64  initially form a heterogeneous composition within manifold  50 . The heterogeneous composition is then channeled through manifold  50  and into static mixer  52  wherein the heterogeneous composition is mixed and/or blended to form fully hydrated firefighting composition  12 . More specifically, static mixer  52  facilitates blending or mixing the heterogeneous composition without storage within static mixer  52 . Thus, the heterogeneous composition is channeled through static mixer input  114 , mixed within static mixer  52  without storage, and discharged from static mixer discharge  116  as a fully blended, homogeneous firefighting composition  12  that is also fully hydrated when discharged from static mixer  52 .  
         [0043]     Described herein is a method and systems that may be utilized to produce a fully hydrated firefighting composition that does not require storage prior to being utilized to fight fires. The systems described herein are configured to receive an operator input indicative of the quantity of firefighting composition to produce, the percentage of gel concentrate within the firefighting composition, and the percentage of colorant within the firefighting composition. The computing module automatically, operates a plurality of pumping modules to channel the heterogeneous solution formed by the hydrating fluid, the gel concentrate, and the colorant to a mixing station. The mixing station is then utilized to fully mix the heterogeneous composition to produce a fully hydrated or homogeneous firefighting composition.  
         [0044]     More specifically, a pump supplies freshwater to a manifold. Detecting the freshwater flowstream, a microprocessor causes a colorant to be injected into the flow. As the flow continues, a second microprocessor again measures the flow and proportionally causes a chosen amount of gel concentrate to be injected into the stream. The heterogeneous gel concentrate and water solution move downstream and enter the multiple stage static or dynamic mixer wherein the heterogeneous solution is combined to form a homogeneous fully hydrated gel solution of the requested color, wherein the viscosity does not substantially vary by more than 25% within a twenty-four hour period following discharge of the gel composition from the system.  
         [0045]     Moreover, by utilizing a microprocessor to control the injection rates for both color and gel concentrate, the blending process will allow Long Term Gel Retardant to be produced in various viscosities and colors as desired by the end-user in a single step, instant, and continuous process without any storage of the product within the static mixer. Accordingly, the storage requirement for known firefighting compositions is eliminated, and thus creating retardant inventory that may not be needed is eliminated by eliminating the storage requirement that is required in a two-step process.  
         [0046]     A hydro-mechanical system may also be used. For example, water pressure/flow in the pipes can be used to cause a proportioner to actuate a piston to inject concentrate into the flow of the water.  
         [0047]     While the invention has been described in terms of various. specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.