Abstract:
An apparatus for treating frac water may include a vacuum container to support a vacuum, a heating device to heat the vacuum container, a spiral auger to rotate to separate the frac water being positioned within the vacuum container, a condenser to condense the water vapor to liquid water, a second vacuum chamber to receive the liquid water and a storage container to store the liquid water.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to fracturing and more particularly to the purification of a fluid for example water after fracturing. 
       BACKGROUND 
       [0002]    Hydraulic fracturing, often called fracking, fracing or hydrofracking, is the process of initiating and subsequently propagating a fracture in a rock layer, employing the pressure of a fluid as the source of energy. The fracturing, known as a frack job (or frac job), is done from a wellbore drilled into reservoir rock formations, in order to increase the extraction and ultimate recovery rates of oil and natural gas. 
         [0003]    Hydraulic fractures may be natural or man-made and are extended by internal fluid pressure which opens the fracture and causes it to extend through the rock. Natural hydraulic fractures include volcanic dikes, sills and fracturing by ice as in frost weathering. Man-made fluid-driven fractures are formed at depth in a borehole and extend into targeted formations. The fracture width is typically maintained after the injection by introducing a proppant into the injected fluid. Proppant is a material, such as grains of sand, ceramic, or other particulates, that prevent the fractures from closing when the injection is stopped. 
         [0004]    One use of hydraulic fracturing is in stimulating water wells. In that case, the fluid used may be pure water (typically water and a disinfectant such as bleach). 
         [0005]    Frac water may be water and various minerals and debris that results from fracturing. The frat water must be processed to eliminate the minerals and debris so that the substantially pure water may be returned to the environment. 
       SUMMARY 
       [0006]    An apparatus for treating frac water may include a vacuum container to support a vacuum, a heating device to heat the vacuum container, a spiral auger to rotate to separate the frac water being positioned within the vacuum container, a condenser to condense the water vapor to liquid water, a second vacuum chamber to receive the liquid water and a storage container to store the liquid water. 
         [0007]    The vacuum container may maintain a sufficient vacuum to boil water at approximately 100° F. and to form water vapor; 
         [0008]    The vacuum chamber may include a substantially circular cross-section. 
         [0009]    The vacuum chamber may include a input port to receive the frac water. 
         [0010]    The vacuum chamber may include a first output port to discharge the debris. 
         [0011]    The vacuum chamber may include a second output port to discharge the water vapor. 
         [0012]    A first passageway may connect the vacuum chamber and the condenser chamber. 
         [0013]    A second passageway may connect the second vacuum chamber and the condenser chamber. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The invention may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which, like reference numerals identify like elements, and in which: 
           [0015]      FIG. 1  illustrates a side cross-sectional view of the fluid purification device of the present invention; 
           [0016]      FIG. 2  illustrates an end cross-sectional view of the fluid purification device of the present invention; 
           [0017]      FIG. 3  illustrates a flow diagram of the steps of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]      FIG. 1  illustrates a fluid purification device  100  of the present invention which may include a vacuum container  101  which may be substantially an elongated cylinder which may be formed from metal, steel, glass, plastic or other type of material and which may be a hollow cylinder. The vacuum container  101  may define a vacuum cavity  103 . The vacuum container  101  may include a rotatable shaft  105  which may extend through the longitudinal direction of the vacuum container  101  and which may include a spiral auger  107  which may include an auger blade which may be relatively thick and impregnated to include a non-stick surface as well as the trough the auger rest in. The vacuum container  101  may include an input narrow portion  109  which may define a input shoulder  113  and a output narrow portion  111  which may define an output shoulder  115 . O-rings may extend around the interior surface of the input narrow portion  109  and the output narrow portion  111  to provide a seal for the shaft  105  and the spiral auger  107 .  FIG. 1  additionally illustrates a pressure relief valve  149  to relieve the pressure within the vacuum container  101  if the pressure should exceed a predetermined pressure value. 
         [0019]    In operation, a vacuum sufficient to boil water at substantially hundred degrees Fahrenheit is formed within the vacuum cavity  103  and frac fluid which may be frac water enters the input port  119  of the input narrow portion  109 . The rotating shaft  105  rotates the spiral auger  107  to help separate the water from the debris and minerals. Additionally, the vacuum encourages the water to enter the vapor state to encourage the separation from the debris and materials. The debris material and minerals and perhaps some water produced output from the vacuum chamber  101  through the first outlet port  131 . 
         [0020]      FIG. 1  additionally illustrates a second output port  133  which may be positioned at the top of the vacuum container  101  and which may be connected to a first transfer passageway  137  which may be a tube to allow the water vapor which has been vaporized within the vapor container  101  to be transferred to the condenser  135 . The first transfer passageway  137  may be connected to the condenser  135  to transfer the water vapor (steam) from the vacuum container  101  to the condenser  135 . 
         [0021]    The condenser  135  condenses the water vapor to liquid water which now should be substantially pure. The liquid water enters a vacuum chamber  141  by a second transfer passageway  143  which may connect the condenser  135  and the vacuum chamber  141 . The substantially pure water may be transferred from the vacuum chamber  141  to a storage container  145  through a third transfer passageway  147 . The water may be stored in the storage container  145  until needed. 
         [0022]    The pressure inside the vacuum container  101  and the vacuum chamber  141  may be between substantially 0.25 to 2 lbs/inch. The operating temperature of the vacuum container  101  and the vacuum chamber  141  may be between substantially 400 to 500 degrees Fahrenheit. The pressure is equivalent to exposing the frac water to the atmospheric pressure at substantially 50,000 to 80,000 feet above the surface of the earth. At this altitude and correspondingly in the vacuum container  101  and the vacuum chamber  141  water may boil at room temperature and may boil below room temperature. The operating temperature may allow the frac water to flash boil. The agitation of the frac water may compensate for the low pressure within the vacuum container  101  and the vacuum chamber  141  With so little pressure the inside of the vacuum chamber  141  and the vacuum container  101  unit a portion of the heat may need to be transferred by physical contact of the rotating shaft  105 . Since the vacuum may provide insulation, the heating requirements may be reduced. The heat may transfer to the frac water by contact with the rotating shaft  105  and the interior surface of the vacuum container  101 . This apparatus may facilitate the processing of large volumes of frac water at a constant rate. 
         [0023]      FIG. 2  illustrates a fluid purification device  100  of the present invention which may include a vacuum container  101  which may be substantially an elongated cylinder which may be formed from metal, steel, glass, plastic or other type of material and which may be a hollow cylinder. The vacuum container  101  may define a vacuum cavity  103 . The vacuum container  101  may include a rotatable shaft  105  which may extend through the longitudinal direction of the vacuum container  101  and which may include a spiral auger  107  which may include an auger blade which may be relatively thick and impregnated to include a non-stick surface as well as the trough the auger rest in. A splash guard  104  may cooperate with the auger blade in order to limiting the splashing of the fluid. The vacuum container  101  may include an input narrow portion  109  which may define a input shoulder  113  and a output narrow portion  111  which may define an output shoulder  115  (not shown in  FIG. 2 ). O-rings may extend around the interior surface of the input narrow portion  109  and the output narrow portion  111  to provide a seal for the shaft  105  and the spiral auger  107 . A pressure relief valve  149  relieves the pressure within the vacuum container  101  if the pressure should exceed a predetermined pressure value (not shown in  FIG. 2 ).  FIG. 2  illustrates opposing heating devices  102  which may be positioned on opposing sides of the auger  107  which may extend the substantial length of the vacuum container  101  and provide heat to keep the temperature within the vacuum container  101  at approximately 100° plus or minus a range of xxx. The vacuum may be sufficient to cause the liquid water to boil into a vapor state and may fall within the range of xxx atmospheres. 
         [0024]      FIG. 2  additionally illustrates a second output port  133  which may be positioned at the top of the vacuum container  101  and which may be connected to a first transfer passageway  137  which may be a tube to allow the water vapor which has been vaporized within the vapor container  101  to be transferred to the condenser  135 . The first transfer passageway  137  may be connected to the condenser  135  to transfer the water vapor (steam) from the vacuum container  101  to the condenser  135 . 
         [0025]    The condenser  135  condenses the water vapor to liquid water which now should be substantially pure. The liquid water enters a vacuum chamber  141  by a second transfer passageway  143  which may connect the condenser  135  and the vacuum chamber  141 . The substantially pure water may be transferred from the vacuum chamber  141  to a storage container  145  through a third transfer passageway  147 . The water may be stored in the storage container  145  until needed. 
         [0026]      FIG. 3  illustrates the steps of the present invention and illustrates establishing a vacuum in step  301 , separating water from debris in the vacuum in step  303 , condensing the separated water vapor to form a liquid in step  305  and storing the water in step  309 . 
         [0027]    While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed.