Abstract:
A method and apparatus for water remediation in general and particularly, for killing bacteria, algae and other microorganisms in water used to fracture-stimulate oil and gas wells and using a coagulant and/or a flocculant for removing the dead microorganisms. A biocide is first introduced into a pit or tank containing the water to be treated and after the microorganisms are dead, the flocculent is added to the biocide-treated water to remove the dead microorganisms. Sequential introduction of the biocide and flocculant into the water to be treated may be accomplished by a number of techniques and after each biocide application the water is tested to determine the remaining living microorganism concentration. The clarity of the treated water is then determined after removal of the dead microorganisms from the water using the flocculant. Recycle and circulation pumps are used in combination with treatment tanks, stationary and movable booms and other equipment to sequentially introduce the biocide and the flocculant into the pit or tank and diffuse these chemicals in the water.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0001]    Water used to fracture-stimulate oil and gas wells is typically characterized by fresh water which may be brought to the well area by truck or pipe or from a water source on location. The water may also include saltwater and/or other chemicals, such as clay stabilizers, corrosion inhibitors, friction reducers and gelling agents. Prior to and in the course of use, and while standing in the pit, tank or like reservoir or container, the water becomes contaminated with bacteria, algae and other microorganisms which degrade fracturing visosifiers, cause corrosion and plug flow paths in the producing reservoir. Accordingly, it is desirable to remove the bacteria, algae and microorganisms from the fracture-stimulate water in order to minimize operational problems associated with well treatment. 
       SUMMARY OF THE INVENTION 
       [0002]    This invention relates to the treatment and remediation of various water and particularly, water used to fracture-stimulate oil and gas wells, by initially treating the water (typically water or water compositions) with a biocide which is specific to the bacteria, algae or microorganisms (hereinafter called microorganisms) in the water, to kill the microorganisms. Once the microorganism kill is determined by testing the biocide-treated water, the water is treated with a coagulant, flocculant or flocculants to induce precipitation of the microorganisms in the pit, tank or other water container, clarify the water and present a substantially clear treatment water. A number of different types of equipment can be utilized to achieve the respective biocide/flocculant infusion into the water to be treated, including circulation pumps; mixing containers which receive a stream of the water to be treated and first, the biocide and later the flocculant; stationary and movable booms which serve as spargers to distribute the treated water uniformly in a pit; and associated equipment. The biocide and flocculant additives can be sequentially added to and diffused in water to be remediated in a treatment vessel, pit or tank by dumping the additives in the vessel, pit or tank or directly in the water flow line by use of one or more mixers or a hopper and auger combination or a venturi and hopper apparatus and by pumping and other techniques disclosed herein and known to those skilled in the art. Testing of the biocide-treated water is typically effected by tests known to those skilled in the art for determining the microorganism kill and the efficiency of removal of these dead microorganisms by a flocculant or coagulant is typically determined by procedures such as ajar test. Depending upon the results of the jar test, more flocculant or coagulant may be added to further remove microorganisms killed by the biocide. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    The invention will be better understood by reference to the accompanying drawings, wherein: 
           [0004]      FIG. 1  is a schematic of a typical water remediation apparatus or system of this invention, which includes a submerged boom provided with openings for introducing a treated water into a pit containing a body of water to be treated and a recycle pump and a mixing tank, wherein water to be treated is recycled or recirculated by the pump from the pit, through the mixing tank and back into the pit through the boom, to first diffuse the biocide additive and later a flocculant or coagulant additive into the pit water; 
           [0005]      FIG. 2  is a schematic of a mixing tank and an auger and hopper system for introducing biocide or a flocculant into water to make a pumpable concentrate in a mixing tank; 
           [0006]      FIG. 3  is a schematic of a mixing tank and a venturi and hopper system for first introducing biocide or a flocculent into water to make a pumpable concentrate in a mixing tank; 
           [0007]      FIG. 4  is a schematic of a mixing tank and a treatment pump for first pumping biocide or a coagulant from a drum or respective drums into the water in the mixing tank to make a pumpable concentrate; 
           [0008]      FIG. 5  is a schematic of a mixing tank fitted with a venturi and hopper combination for pneumatically feeding a biocide or flocculant from the hopper into the mixing tank to create a chemically concentrated water solution; 
           [0009]      FIG. 6  is a schematic of a pit containing water to be treated, a submerged boom and a recycle pump connected to the boom and to a venturi and hopper combination for first introducing a biocide additive and then a flocculant or coagulant additive into the pit water through the submerged boom by operation of the venturi; 
           [0010]      FIG. 7  is a schematic of a recycle pump, mixer and pit for introducing untreated or partially-treated water from the pit into a movable boom after adding biocide and flocculant/coagulant additives into the water, wherein the boom can be moved from one end of the pit to the other, to disperse the resulting chemically-concentrated solution into all areas of the pit; 
           [0011]      FIG. 8  is a schematic of a mixer, recycle pump and a circulation pump positioned near a pit containing water to be treated and a boom immersed in the water, wherein the recycle pump circulates untreated or partially-treated water from the pit to a point of infusion of a biocide and flocculant/coagulant, through the boom and back into the pit and the circulation pump circulates the water in the pit; 
           [0012]      FIG. 9  is a schematic of a pair of mixers in association with a pit or tank, wherein the additive biocide and flocculant or coagulant are introduced directly into the mixers in a water stream flowing through the mixers into the pit or tank; 
           [0013]      FIG. 10  is a schematic of a mixer in association with a pit or tank containing water to be treated, wherein the additive biocide and flocculant or coagulant are introduced directly into a mixer in a water stream flowing from a tank truck through the mixer into the pit or tank; 
           [0014]      FIG. 11  is a schematic of a mobile mixing truck and separate mixer in association with a pit or tank, wherein the additive biocide and flocculant are introduced from a solution in the mobile mixer and then through another mixer in a water stream flowing from the mobile mixer mobile through the second mixer into the storage pit or tank; 
           [0015]      FIG. 12  is a schematic of a pit or tank from which water is pumped through a first mixer for first receiving a biocide and/or a flocculant or coagulant and to a second mixer for receiving additional biocide and/or flocculant, as needed and then directly to the well or to a tank; 
           [0016]      FIG. 13  is a schematic of a bulk biocide and flocculant or coagulant container, truck or the like for sequential use and fitted with an air or water access for sequentially forcing the contents of the container into a pit containing water to be treated by introduction of the air or gas stream into the container; 
           [0017]      FIG. 14  is a schematic of a pit fitted with a mixer and a sprayer, sprinkler or sparger system containing sparger nozzles or openings for circulating untreated or partially-treated water from a pit or reservoir through a mixer, where a biocide or flocculant coagulant is added, and then through the sparger and back into the storage pit by a recycle pump and further circulating the water using an optional secondary circulation pump provided to circulate the pit and diffuse the biocide and flocculant/coagulant additives into the water; and 
           [0018]      FIG. 15  is a schematic of a pit fitted with a mixer and a spray head or a nozzle connected to the discharge line of a recycle pump for circulating untreated or partially treated water from a storage pit back into the pit using the spray head or nozzle, with an optional secondary circulation pump provided to further circulate the pit and diffuse the biocide and flocculant/coagulant additives into the water. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0019]    Referring initially to  FIG. 1  of the drawings, in one embodiment of the invention the water used to fracture-stimulate oil and gas wells is located in a pit  29  and is generally designated by reference numeral  30  as pit water, reference numeral  30   a  as circulated, chemically partially-concentrated water and reference numeral  31  as chemically super-concentrated water. Both the chemically partially-concentrated water and chemically super-concentrated water have varying concentrations of either or both of the biocide and flocculent or coagulant additives designated by reference numeral  35 . A boom  24  typically includes several lengths of boom pipe  25  of selected size, typically connected by quick disconnect or threaded pipe connectors  71   a  and is typically submerged in the pit water  30  and maintained in the submerged condition by boom floats  27 . Each length of the boom pipe  25  is provided with spaced-apart pipe nozzles or openings  26  and one end of a boom hose  32  is connected to the boom  24  at a pipe hose connection  25   b . The opposite end of the boom  24  from the pipe hose connection  25   b  is typically closed by a pipe cap  25   a . The opposite end of the boom hose  32  from the pipe hose connection  25   b  is connected to a pump discharge line  23 , typically at a boom hose connection  33 . The pump discharge line  23  is connected at one end to the recycle pump discharge  15  of a recycle pump  13 , while the opposite end of the pump discharge line  23  is attached to a tank intake hose  12   b , typically at a tank intake hose connection  12   c . The opposite end of the tank intake hose  12   b  is typically connected to a tank intake line valve  12   a , which also connects to a tank intake line  12 , fitted in the bottom of the typical cylindrical wall  2  of a mixing tank  1 , having a tank bottom  3 . A tank suction pipe  4  is submerged in a quantity of chemically super-concentrated water  31  contained in the mixing tank  1 , and the tank suction pipe  4  typically includes a telescoping suction pipe  6 , slidably fitted in a fixed suction pipe  5 , to vary the outward flow of the chemically super-concentrated water  31  from the mixing tank  1 , through a tank suction line  7 , connected to the fixed suction pipe  5  of the tank suction pipe  4 . A tank suction line valve  8  is fitted in the tank suction line  7  and is connected to one end of a tank recycle hose  9 , typically at a tank recycle hose connection  10 . The opposite end of the tank recycle hose  9  is fitted to a tank recycle hose nipple  11 , typically at a second tank recycle hose connection  10  and the tank recycle hose nipple  11  is, in turn, connected to a recycle pump suction line  17  that terminates at the recycle pump suction  14  of the recycle pump  13 . A typically gasoline recycle pump motor  16  drives the recycle pump  13 . A suction connecting segment  20  contains a recycle pump suction line valve  19  and has one end connected to the recycle pump suction line  17  and the opposite end attached to a pit suction hose  22 , typically by recycle pump suction line hose connection  18  and segment hose connection  21 , respectively. The opposite end of the pit suction hose  22  is immersed in the pit water  30  located in the pit  29 . Accordingly, additives  35 , which may typically be a powder, granule or a liquid, are introduced into the mixing tank  1 , either directly by dumping or through an additive intake line  36  and stirred, either mechanically as hereinafter further described, or by hand, using a paddle  2   a.    
         [0020]    According to the above described embodiment of the invention, the first additive  35  is initially introduced into the mixing tank  1  to define the chemically super-concentrated water  31 , as a biocide designed to kill specific bacteria, algae and other microorganisms located in the pit water  30 . The biocide or biocides are initially tested on the bacteria, algae and other microorganisms (hereinafter called microorganisms) and a specific biocide or biocides is chosen for introduction into the mixing tank  1 . Other chemicals can also be added to the chemically super-concentrated water  31  to adjust the PH or otherwise alter the physical characteristics of the chemically super-concentrated water  31  to enhance the effect of the biocide(s), as hereinafter described. When the chosen biocide or biocides is introduced into the mixing tank  1 , the recycle pump suction line valve  19 , tank suction line valve  8  and tank intake line valve  12   a  are opened, the recycle pump  13  is energized and the chemically super-concentrated water  31  in the mixing tank  1  is pumped through the telescoping suction pipe  6  and fixed suction pipe  5  of the tank suction pipe  4 . From this point it is pumped through the tank suction line valve  8  from the tank suction line  7 , into the recycle pump suction line  17  and then into the recycle pump suction  14  of the recycle pump  13 . Chemically partially-concentrated water  30   a  is then pumped from the recycle pump discharge  15  through the pump discharge line  23  and this stream is split into a first stream flowing through the boom hose  32  and a second stream flowing through the intake hose  12   b  and back through the tank intake line valve  12   a , into the mixing tank  1 . The stream of chemically partially-concentrated water  30   a  flows through the boom hose  32  and is directed through the pipe hose connection  25   b  on one end of the boom  24  and dispersed into the pit water  30  in the pit  29 , through the spaced-apart pipe nozzles or openings  26  in the connected segments of the boom pipe  25 . Accordingly, the pit water  30  becomes mixed, diffused and infused with chemically partially-concentrated water  30   a , which has been diluted from chemically super-concentrated water  31  from the mixing tank  1  to the chemically partially-concentrated water  30   a.  This recirculation continuously raises the chemical concentration of the pit water  30  which is circulated back to the recycle pump  13  through the pit suction hose  22 . The pit suction hose  22  is connected to one end of the suction connecting segment  20 , which receives the recycle pump suction line valve  19 , and the opposite end of the suction connecting segment  20  terminates in the recycle pump suction  14  of the recycle pump  13 . Continued circulation of the mixed biocide additive  35  and the chemically super-concentrated water  31  in this manner insures that the pit water  30  will ultimately be fully infused with and treated by the biocide additive  35  and the microorganisms located in the pit water  30  killed by the biocide. 
         [0021]    In the second phase of the invention, after sufficient time is allowed for the selected biocide or biocides to kill the microorganisms in the pit water  30  in the pit  29  as heretofore described, the water is tested to determine the remaining concentration of live microorganisms, if any. After the desired microorganism kill is determined, a flocculant or coagulant (hereinafter called flocculant) is added as an additional additive  35 . The flocculant additive  35  is typically introduced into the mixing tank  1  through the additive line  36  in the same manner as the biocide(s) and is mixed in the mixing tank  1 , typically using a mechanical mixer  37  or a paddle  2   a , as described above with respect to the biocide mixing procedure. The chemically super-concentrated water  31  which now includes the flocculant and the dead microorganisms killed by the biocide, is then introduced into the supply of pit water  30  in the pit  29  through the tank suction pipe  4 , the tank recycle hose  9 , the recycle pump suction line  17 , the recycle pump  13 , the pump discharge line  23  and the boom hose  32 , in the manner described above with respect to the biocide treatment. The flocculant is thus introduced into the pit water  30  in the pit  29  through the boom hose  32 , the boom  24  and the pipe openings  26 . The flocculant is continually added to the pit water  30  in the pit  29  until the proper concentration is achieved by circulating the increasingly concentrated pit water  30  through the pit suction hose  22 , the suction connecting segment  20 , the recycle pump suction line  17  and into the recycled pump suction  14  of the recycle pump  13 . If necessary, an additional type of flocculant can be added, typically in the manner described above. The flocculant serves to precipitate the microorganisms killed by the biocide treatment to the bottom of the pit  29  and clarify the flocculated and biocide-treated pit water  30 , typically to facilitate use of the clarified pit water as a fracture-stimulant medium for oil and gas wells (not illustrated) in the course of pumping the water downhole in the well according to conventional techniques. The clarity of the flocculated and biocide-treated pit water  30  is tested after application of the flocculant to determine whether additional flocculation is necessary. The diffusion and infusion of both the biocide and flocculant additives into the pit water  30  is aided by natural convections of the water due to environmental heating and cooling. 
         [0022]    Referring now to  FIG. 2  of the drawings, it will be appreciated by those skilled in the art that both the biocide and the flocculant additives  35  may be sequentially introduced into the mixing tank  1  by various techniques. Typical of these techniques is the use of an auger  43 , extending from a hopper  42  and including an auger motor  44 , attached to the auger  43  for rotating the auger flutes inside a casing. A typically dry biocide additive  35  is initially introduced into the hopper  42  and is fed from the hopper  42  through the auger  43 , driven by an auger motor  44 . The biocide additive  35  is thus introduced in a desired quantity into the mixing tank  1  at the terminal or discharge end of the auger  43  positioned over the mixing tank  1  and is mixed in the chemically super-concentrated water  31  in the mixing tank  1  as heretofore described. The resulting chemically super-concentrated water  31  is then caused to flow from the mixing tank  1  through the recycle pump  13  illustrated in  FIG. 1  and from there into the pit water  30  in the pit  29 , further illustrated in  FIG. 1 . The pit water  30  is then pumped to the recycle pump  13 , through the pit suction hose  22 , as described above with respect to  FIG. 1  of the drawings. As further illustrated in  FIG. 2 , a mechanical mixer  37  may be positioned such that the mixer shaft  39  and mixer blades  40  extend into the chemically super-concentrated water  31  and the mixer motor  38  is activated to rotate the mixer blades  40  at a selected speed and diffuse and blend the biocide additive  35  into the chemically super-concentrated water  31  in the mixing tank  1 . After sufficient time is allowed for killing of the various microorganisms located in the pit water  30  and the chemically super-concentrated pit water  31  by the biocide additive  35 , and after a test or tests confirm the desired microorganism kill, a flocculant additive  35  is added to the hopper  42  and is distributed by means of the auger  43  into the mixing tank  1  for mixing with the chemically super-concentrated water  31 , typically by operation of the mechanical mixer  37 . The resulting chemically super-concentrated water  31  is then diluted with water from the pit  29  and a portion of this chemically partially-concentrated water  30   a  is returned to the mixing tank  1 , while the rest of the water is circulated to the pit  29 , using the recycle pump  13  and the boom  24 , as described above with respect to  FIG. 1  of the drawings. As further described above with respect to  FIG. 1  of the drawings, the now flocculated and biocide-treated pit water  30  is tested for clarity to determine whether additional flocculation is necessary. 
         [0023]    Referring now to  FIG. 3  of the drawings, in another embodiment of the invention the biocide and the flocculant additives  35  can be added in sequence to a hopper  42 , which is mounted on a venturi  45 , wherein air, water or an alternative fluid can be introduced into the venturi  45  and the resulting zone of low pressure formed in the venturi  45  facilitates an initial flow or movement of liquid or powdered biocide additive  35  and later, a flocculent additive  35 , through the water outlet stream  47  and into the mixing tank  1 . As in the case of the other embodiments in the invention, it will be appreciated that the biocide additive  35  is first added to the hopper  42  and dispensed into the mixing tank  1  to create the chemically super-concentrated water  31 , using the venturi  45 . The flocculant additive  35  is later added to the hopper  42  and is dispensed into the mixing tank  1  through the venturi  45  after additional time has elapsed to insure that the desired concentration of microorganisms located in the biocide-treated pit water  30  are dead. The resulting chemically super-concentrated water  31  is then diluted with water from the pit  29  and a portion is returned to the mixing tank  1  while the rest is circulated to the pit  29  using the recycle pump  13  and the boom  24 , as described above with respect to  FIG. 1  of the drawings. Testing of the flocculated and biocide-treated pit water  30  is effected as described above with respect to  FIGS. 1 and 2  of the drawings. 
         [0024]    As illustrated in  FIG. 4  of the drawings in another embodiment of the invention, the mixing tank  1  and mechanical mixer  37  combination illustrated in  FIGS. 2 and 3  is utilized in connection with a treatment pump  48 , fitted with a treatment suction hose  55 , that extends from the treatment pump suction  49  to a treatment container hose  57 , typically at a treatment suction hose connection  56 . The treatment container hose  57  extends to a treatment container  58 , such as a drum, for containing a biocide or flocculant additive. The biocide and later, the flocculant additive located in the treatment container(s)  58  is pumped through the treatment container hose  57  and the treatment suction hose  55  and the pump  48  and through a treatment pump discharge  50  and a treatment pump discharge line  51 , connected to a treatment discharge hose  52 , typically at a treatment discharge connection  53 . The biocide and flocculant elements or additives are sequentially introduced into the mixing tank  1  at selected time intervals to first treat the pit water  30  and kill the microorganisms and then flocculate the dead microorganisms, after the additives have been thoroughly mixed and diffused with the pit water  30 . Recirculation of the now flocculated and treated pit water  30  through a pit  29 , using a recycle pump  13  and boom  24  is typically accomplished as described above with respect to  FIG. 1  of the drawings. A typically gasoline pump motor  54  drives the treatment pump  48 , as further illustrated in  FIG. 4 . 
         [0025]    As illustrated in  FIG. 5  of the drawings, in another embodiment of the invention a mixing tank  1  is illustrated, having a typically cylindrical wall  2  and a tank bottom  3 . The mixing tank  1  is fitted with a mechanical mixer  37 , having a mixer shaft  39  and blades  40  extending into a quantity of chemically super-concentrated water  31  in the mixing tank  1 . A tank suction pipe  4  is also provided in the mixing tank  1  and is submerged in the chemically super-concentrated water  31 , wherein a telescoping suction pipe  6  is slidably fitted in a fixed suction pipe  5  to adjust the rate of flow of chemically super-concentrated water  31  through the tank suction pipe  4  and into the recycle pump suction  14  of a recycle pump  13  ( illustrated in  FIG. 1 ). Referring again to  FIG. 1 , a portion of the chemically partially-concentrated pit water  30   a  is circulated back into the mixing tank  1  as it is discharged from the recycle pump discharge  15 , through the tank intake hose  12   b  and the tank intake line valve  12   a , into the bottom of the mixing tank  1 . A biocide and later, a flocculant, are typically sequentially introduced to the mixing tank  1  as successive additives  35 , by fluidizing the additive  35  with an air stream, typically inside a pressurized treatment container  58  ( FIG. 13 ) so that the additive  35  can be transported by pressure over the chemically super-concentrated water  31  in the mixing tank  1 . When the resulting chemically super-concentrated water  31  is treated with the biocide and has been circulated back to the tank or pit as described with respect to  FIG. 1  of the drawings, a flocculant additive  35  is introduced into the treatment container  58  ( FIG. 13 ) and is similarly directed into the chemically super-concentrated water  31  in the mixing tank  1 , also by operation of the typically air or gas flowing through the gas inlet line  46  and the treatment container nipple  59  ( FIG. 13 ). 
         [0026]    Referring now to  FIG. 6  of the drawings, in still another embodiment of the invention a venturi  45  is added to the pump discharge line  23  extending from the recycle pump discharge  15  of a recycle pump  13 . The venturi  45  is connected to a water outlet line  47 , attached to a boom hose  32 , typically by a venturi connection  45   a . The opposite end of the boom hose  32  is attached to one end of the boom  24  at a pipe hose connection  25   b , for introduction of a biocide and later, a flocculant additive  35 , into the hopper  42 , through an additive line  36 . As in the embodiments described above with respect to  FIG. 1 , the initial additive  35  is a biocide for killing the microorganisms in the pit water  30  and later after testing the biocide-treated pit water  30  a flocculant additive  35  is introduced for precipitating the dead microorganisms and clarifying the flocculated treated pit water  30  to a tested degree of clarity. A recycle pump suction line  17  extends from the recycle pump suction  14  of the recycle pump  13  to a segment hose connection  21 , which attaches a pit suction hose  22  to the recycle pump suction line  17 . The opposite end of the pit suction hose  22  extends into the pit water  30  in the pit  29 , where the boom  24  is submerged in the pit water  30 , typically using boom floats  27 . Accordingly, when it is desired to introduce a biocide additive  35  into the pit water  30  and the pit  29 , the typically powdered, pelletized or granulated biocide additive  35  is initially introduced into the additive line  36 , and from there into the hopper  42 , where it flows with the pit water  30  (pumped from the pit  29  through the pit suction hose  22  and recycle pump suction line  17 , through the recycle pump  13  into the pump discharge line  23 ) and through the venturi  45 , through the boom hose  32  and the boom  24 , as chemically partially-concentrated water  30   a . Mixing of the biocide additive  35  with the pit water  30  is thus accomplished without the use of the mixing tank  1  illustrated in  FIGS. 1-5  of the drawings. When a sufficient quantity of biocide additive  35  is provided in the pit water  30  to sufficiently treat the pit water  30  and kill the microorganisms therein, a flocculant additive  35  is pumped or introduced into the additive line  36  and the hopper  42 , for distribution by means of the venturi  45  in the same manner as the biocide previously introduced into the pit water  30 . The flocculant additive  35  in the pit water  30  precipitates the dead microorganisms and clarifies the flocculated and biocide-treated pit water  30  for more efficient use in the fracturing operation. 
         [0027]    Referring now to  FIG. 7  of the drawings, in still another embodiment of the invention a pit  29  is fitted with a boom harness  28 , extending from a boom  24  and provided with a boom control line  28   a , which extends from the boom  24  around a first boom pulley  28   b  and from the first boom pulley  28   b  to a second boom pulley  28   b  located at the opposite side of the pit and from there across the pit  29 , back to the boom harness  28 . This mechanical arrangement facilitates movement of the boom  24 , either in a submerged condition as illustrated in  FIGS. 1 and 6  or on the surface of the pit water  30  located in the pit  29 , by tension applied to the boom control line  28   a , to more evenly distribute biocide and later flocculant additives  35  from the mixer  37 , through the boom  24  and the pipe openings  26  in the boom pipe  25  and into the pit water  30 . Recirculation of the pit water  30  is typically accomplished using a recycle pump  13 , which discharges the pit water  30  through a pump discharge line  23 , typically connected to a boom hose  32  by a boom hose connection  33 . The pit water  30  is pumped from the pit  29  through a pit suction hose  22  having one end connected to a recycle pump suction line  17  (typically at a recycle pump suction line hose connection  18 ) that extends to the recycle pump suction  14  of the recycle pump  13 . The opposite end of the pit suction hose  22  is immersed in the pit water  30  in the pit  29 . 
         [0028]    Accordingly, a biocide additive  35  can be initially introduced into the pit water  30  using a mixer  37  of any chosen design and the chemically partially-concentrated water  30   a  then pumped through the boom  24  to diffuse and disperse the biocide therein, using the recycle pump  13  and boom  24 , as illustrated in  FIG. 6 . The boom  24  is typically moved at a desired rate from one end of the pit  29  to the other using the boom harness  28  and the boom control line  28   a , extended around the oppositely-disposed, spaced-apart boom pulleys  28   b . After laboratory tests confirm that the microorganisms in the biocide-treated pit water  30  are dead, a flocculent additive  35  is introduced into the biocide-treated pit water  30  in any desired manner, but typically using the mixer  37  or any of the techniques described herein, to define a flocculated and biocide-treated pit water  30 . 
         [0029]    Referring now to  FIG. 8  of the drawings, in another embodiment of the invention a recycle pump  13  can be provided near a pit  29  containing a quantity of pit water  30  as described with respect to  FIG. 7 , while a circulation pump  13   a  is typically also located near the pit  29 , for thoroughly circulating and mixing the pit water  30 , which is first treated with a biocide additive  35  and later a flocculant additive  35 , typically introduced therein using a mixer  37 , as described above with respect to  FIG. 7 . The recycle pump  13  is typically provided with a pump discharge line  23 , connected to a boom hose  32 , which is connected to the mixer  32 , typically using a boom hose connection  33  and the extending end of the boom hose  32  is secured to one end of a boom  24 , typically using a pipe hose connection  25   b , as described above. As further described above, the boom  24  is typically submerged or floating on the body of pit water  30  and is typically constructed of segments of boom pipe  25  joined at pipe connectors  71   a,  which may be quick-disconnect or threaded pipe connectors, as desired. A pit suction hose  22  has one end immersed in the pit water  30  in the pit  29  and the opposite end connected to a recycle pump suction line  17 , typically at a recycle pump suction line hose connection  18 . Accordingly, the recycle pump suction line  17  extends to the recycle pump suction  14 , while the pump discharge line  23  extends from recycle pump discharge  15  of the recycle pump  13 , to pump and circulate the pit water  30  from the pit  29  through the pit suction hose  22  and the recycle pump suction line  17 , recycle pump  13 , pump discharge line  23  and the boom hose  32  and back into the reservoir of pit water  30 , through the pipe openings  26  in the boom pipe  25  of the boom  24 , to diffuse the respective biocide and flocculent additives into the resulting flocculated and biocide-treated pit water  30 , as described above with respect to  FIG. 7  of the drawings. 
         [0030]    In like manner, the circulation pump  13   a  pumps the pit water  30  through a second pit suction hose  22  located therein, and through a circulation pump suction line connection  18   a  and a circulation pump suction line  17   a , into the circulation pump suction  14   a  and from the circulation pump discharge  15   a  of the circulation pump  13   a . The circulated pit water  30  then flows through a second pump discharge line  23  and into the reservoir of pit water  30 , through a pit discharge hose  34 . The flocculated and biocide-treated pit water  30  is therefore also circulated in the pit  29  using the circulation pump  13   a . Accordingly, mixing and diffusion of the biocide and later the flocculant in the pit water  30  is thus achieved by the recycle pump  13 , boom  24  and a first pit suction hose  22 , as well as the circulation pump  13   a , using the pit discharge hose  34  and a second pit suction hose  22 . Testing of the flocculated and biocide-treated pit water  30  for biocide kill and flocculation efficiency, respectively, of the microorganisms in the pit water is effected as detailed herein. 
         [0031]    Referring now to  FIG. 9  of the drawings, it will be appreciated by those skilled in the art that in a still further embodiment of the invention, water of desired quality from a selected source can be pumped to a first mixer  37  of selected design and a biocide additive  35  initially added to the mixer  37  as heretofore described, for distribution to a second mixer  37 . A flocculent additive  35  is then added to the biocide-treated water in the second mixer  37 , and the flocculated and biocide-treated water is directed into a pit  29  or a tank, typically through a treatment discharge hose  52 . A pump (not illustrated) is typically used for this purpose. It will be further understood that the pit  29  can be replaced by a tank such as a frac tank, holding tank or other container for receiving and storing the treated water. An additional mixer or mixers  37  of selected design can be added to the treatment system for adding additional biocide and/or flocculent additives  35 , as deemed necessary. 
         [0032]    Referring now to  FIG. 10  of the drawings, in another embodiment of the invention a tank truck  65  has a truck tank  65   a  which carries a supply of water and is connected to a mixer  37 , typically by a tank discharge line  67 . If the water in the truck tank  65   a  has not previously been treated with a biocide and/or a flocculant additive  35 , or if additional biocide and/or flocculant is needed, a biocide additive  35  and/or flocculant additive  35  are sequentially introduced into the mixer and the resulting treated water mixture is directed through a treatment discharge hose  52  into a pit or a tank  29 . Under circumstances where the water from the truck tank  65   a  has not been previously treated with a biocide and/or flocculant or has only been partially so treated, and after a sufficient quantity of the biocide additive  35  is introduced into the mixer  37  and then pumped into the pit or tank  29 , sufficient time is allowed for the biocide to kill the microorganisms in the water which has been treated. The flocculant additive  35  is then introduced into the mixer  37 , mixed with the incoming water and discharged through the treatment discharge hose  52  into the pit or tank  29 , to further treat the biocide-treated water, precipitate the dead microorganisms and clarify the concentrated flocculated biocide-treated water. The water is typically pumped from the tank truck  65  into the mixer  37  and the pit or tank  29  by a pump (not illustrated) which may be mounted on the tank truck  65 . 
         [0033]    As illustrated in  FIG. 11  of the drawings, in a still further embodiment, a similar procedure can be used to treat a quantity of water of varying quality using a mixing truck  66  having a mixing tank  66   a,  which is filled with biocide and/or flocculant-treated water, which water is introduced into a mixer  37 , typically through a tank discharge line  67 . Successive charges of a flocculant additive  35  are typically sequentially introduced into the mixer  37  as needed and then into a pit or tank  29  via a treatment discharge hose  52 , for clarifying the water in the pit or tank  29  in the manner detailed above with respect to  FIG. 10  of the drawings. A pump (not illustrated) typically located on the mixing truck  66  may typically be used to pump the concentrated flocculated and biocide-treated water through the mixer  37 , into the pit or tank  29 . 
         [0034]    Referring now to  FIG. 12  of the drawings, in another embodiment of the invention a pit or tank  29  containing a quantity of untreated or biocide and/or flocculant-treated water typically used to fracture-stimulate oil and gas wells is coupled to a first mixer  37  through a tank discharge line  67  and a biocide and/or flocculant additive  35  is initially introduced as needed, into the first mixer  37  and mixed with the water from the pit or tank  29 . The resulting treated water mixture is typically pumped by a pump  13  to a second mixer  37 , where additional biocide and/or flocculant additive  35  may be added, if necessary. The flocculated biocide-treated water is then pumped through a treatment discharge hose  52 , either directly to a well in a well service fracture operation (not illustrated) or to a discharge recipient such as a storage tank  69 . As in the case of the embodiments heretofore described, the pump  13  is typically characterized by a pump suction  14  which receives the initially treated water from the first mixer  37  through the recycle pump suction line  17  and a pump discharge  15 , which discharges the water into the second mixer  37  through a pump discharge line  23 . Moreover, the treated water is first tested after application of the biocide additive  35  and second after the flocculant additive  35  is added, to determine the microorganism kill and water clarity, respectively, as described above. Alternatively, the biocide can be first added to the first mixer  37  and the incoming water from the pit or tank  29  and the flocculant added at a later time to the second mixer  37 . 
         [0035]    Referring now to  FIG. 13  of the drawings, in yet another embodiment, a body of pit water  30 , located in a pit  29  or in a tank or the like is remediated by initial introduction of a biocide chemical from a treatment container  58 , through a treatment discharge hose  52  attached to a treatment container nipple  59 , extending from the drum or treatment container  58  and typically coupled to the treatment discharge hose  52  by a treatment discharge connection  53 . Air or gas may be introduced into the treatment container  58  through a typically gas inlet line  46  to force the typically dry biocide in the treatment container  58  through the treatment discharge hose  52  and into the pit water  30 . Alternatively, the treatment container  58  may be positioned above the pit  29  as illustrated, to facilitate a gravity feed of the biocide when the biocide is a liquid. After the desired kill of microorganisms located in the pit water  30  is effected by the biocide and this kill typically is confirmed by testing the biocide-treated water  30 , a flocculant component may be either added to the treatment container  58  or to a second treatment container  58  containing a dry flocculant and connected to the treatment discharge hose  52 . A quantity of air or gas  46  is introduced into the treatment container  58  to force the dry flocculent through the treatment discharge hose  52  and into the biocide-treated pit water  30 . As in the case of liquid biocide treatment, if the flocculant is also a liquid, the liquid flow of flocculant from the treatment container  58  to the pit  29  may be by gravity. 
         [0036]    Referring now to  FIG. 14  of the drawings, in another embodiment of the invention a sparger  70  is positioned on three sides of a pit  29  and includes multiple sparger pipes  71 , joined by pipe connectors  71  a and elbows  74 , which may be quick-disconnect pipe connectors or threaded pipe connectors, as desired. Pipe nozzles or openings  72  are provided in spaced-apart relationship with respect to each other in the sparger pipes  71 , facing the pit  29  and one end of a boom hose  32  is connected to the sparger  70 , typically at a pipe hose connection  25   b . A mixer  37  of selected design is typically connected to the boom hose  32 . The opposite end of the boom hose  32  is typically connected to the pump discharge line  23  of a recycle pump discharge  15  on a recycle pump  13 , typically at a tank intake hose connection  12   c . The recycle pump  13  is fitted with a recycle pump suction  14  that receives one end of a recycle pump line  17 , the opposite end of which is connected to a pit suction hose  22 , typically by means of a recycle pump suction line hose connection  18 . The free end of the pit suction hose  22  is adapted for immersion in a quantity of pit water  30  which has either been treated with a biocide, typically in the manner disclosed herein, in the pit  29 , or by using the mixer  37 . In the latter case, a biocide additive  35  is added to the mixer  37  by any convenient method and typically by methods heretofore described. Operation of the recycle pump  13  causes pit water  30  to flow through the pit suction hose  22 , the recycle pump suction line  17 , the recycle pump  13  and from the recycle pump  13 , through the pump discharge line  23  and the boom hose  32 , through the sparger  70  and back into the pit  29 , through the respective pipe nozzles or openings  72 , as chemically partially-concentrated water  30   a . A gasoline motor  16  typically drives the recycle pump  13  and a circulation pump  13   a . In one aspect of this embodiment of the invention, the circulation pump  13   a  is provided to circulate the pit  29  and includes a pit suction hose  22 , having one end immersed in the pit water  30  and the opposite end connected by a circulation pump suction line connection  18   a  to a circulation pump suction line  17   a , which terminates at the circulation pump suction  14   a  of the circulation pump  13   a . The pit water  30  pumped through the pit suction hose  22  and the circulation pump suction line  17   a  is also pumped back into the pit  29  through the circulation pump discharge  15   a  and the pump discharge line  23 , as pit water  30 . After testing of the biocide-treated pit water  30  indicates a desirable kill of microorganisms, a flocculent is typically added to the mixer  37  and the biocide-treated and circulated pit water  30  as an additional additive  35  (or directly to the pit water  30 ) to flocculate the dead microorganisms and clarify the resulting concentrated flocculated biocide-treated pit water  30 . This water clarity is determined by testing, typically by the commonly used jar test. Diffusion and thorough infusion of both the biocide and flocculating additives  35  in the pit water  30  is typically achieved by using the recycle pump  13  and the circulation pump  13   a . The sparger  70  can be positioned on only one side or end of the pit  29 , along the entire or a portion of that end or side of the pit  29 . 
         [0037]    As illustrated in  FIG. 15  of the drawings, in another embodiment of the invention a pit  29  contains a quantity of pit water  30  which is first treated in any convenient manner, but typically by adding a biocide additive  35  using a mixer  37 . Later, after the microorganisms in the biocide-treated pit water have been killed by the biocide, a flocculant additive  35  is added. Initial mixing of the respective biocide and flocculant additives  35  with the pit water  30  is typically accomplished by the mixer  37  and diffusion of the additives  35  in the chemically partially-concentrated water  30   a  is effected, in part, by a recycle pump  13  having a pump discharge line  23  connected to a boom hose  32 , typically using a tank intake hose connection  12   c . The mixer  37  is typically connected to the boom hose  32 . The opposite end of the boom hose  32  is connected to a pipe hose connection  25   b  and a spray head  73  is attached to the pipe hose connection  25   b , to facilitate spraying of the chemically partially-concentrated water  30   a  back into the pit water  30  in the pit  29 . Continued circulation of the pit water  30  through the recycle pump  13  is accomplished by a pit suction hose  22 , having one end immersed in the pit water  30  and the opposite end connected to one end of a recycle pump suction line  17 , typically by a recycle pump suction line hose connection  18 . The opposite end of the recycle pump suction line  17  terminates at the recycle pump suction  14  of the recycle pump  13 . 
         [0038]    In a typical aspect of this embodiment of the invention a circulation pump  13   a  is provided for circulating the pit  29  and includes a pump discharge line  23  that communicates with the pit water  30  and with the circulation pump discharge  15   a  of the circulation pump  13   a . One end of a pit suction hose  22  is immersed in the pit water  30  and the opposite end is attached to a circulation pump suction line  17   a , which terminates at the circulating pump suction  14   a  and is typically connected to the pit suction hose  22  by a hose connection  18   a . A gasoline motor  16  typically drives both the recycle pump  13  and the circulation pump  13   a.    
         [0039]    It will be appreciated by those skilled in the art that the fracture-stimulation water which may be treated according to the method of this invention is typically characterized by either fresh water which may be brought in by truck or pipeline, or from a water well or a source on location, or saltwater, which may be produced saltwater or water made salty by additives such as potassium chloride, sodium chloride, calcium chloride or other salts mixed with these components. Still other chemicals may be added to the “frac water” according to the stimulation needs in question and these may include such chemicals as clay stabilizers, corrosion inhibitors, friction reducers and gelling agents known to those skilled in the art. Moreover, typical fracture-stimulation water storage receptacles may include earthen or lined pits, as well as tanks, including mobile frac tanks permanent tanks and the like. 
         [0040]    Moreover, substantially any water supply, including lake and pond water and well water, in non-exclusive particular, can be treated by the method of this invention according to the above disclosure. Accordingly, the water clarity and quality of these and other water sources can be improved under circumstances where this clarity and quality are reduced by the presence of microorganisms. 
         [0041]    Biocides typically used in the water remediation method of this invention include powdered bromine; liquid or powdered or granular isothiazolin; liquid THPS (tetrakis (hydroxymethyl) phosphonium sulfate) powdered bronopol; powdered or granular DBNPA (dibromo-3-nitrilopropionamide) and chlorine, which may include chlorine gas, calcium hypochlorite, typically provided as granules, and sodium hypochorite, typically supplied as a liquid) and other commercially available biocides approved by the EPA. Other treatment chemicals that may be used in the invention to alter the PH and other characteristics of the water to be treated prior to treatment by the biocide are muratic, sulfuric and dry acids, as well as sodium carbonate and caustic soda, in non-exclusive particular. 
         [0042]    Typical flocculants which may be used to flocculate the dead microorganisms killed by the biocide or biocide initially introduced into the water to be treated include anionic, non-ionic and cationic inorganic coagulant/flocculants such as aluminum sulfate, ferric chloride, ferric sulphate, polyaluminum chloride, aluminum chloride, polyaluminum hydroxychloride, aluminum chlorohydrate; ferrousulfatemonohydrate and hydrated lime, in non-exclusive particular. Organic polymers for use may typically include cationic, ionic and non-ionic chemicals such as polyacrylamide, polyamines and polydadmacs, in non-exclusive particular. 
         [0043]    It is understood that additional steps other than settling or floating of the dead microorganisms, can be taken, including filtration and combinations of these methods, as desired or necessary. Moreover, the various mixers  37  may include the illustrated auger  43  and venturi  45 , both in combination with a hopper  42 , as well as other mixing devices such as tub mixers and the like, which are known to those skilled in the art. 
         [0044]    While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.