Abstract:
An insulative cover for large tanks containing a fluid. The insulative cover utilizes rectangular panels to cover a majority of the fluid surface and trapezoidal or wedge shaped panels to form a ring around the rectangular panels. Each panel utilizes a locking rim to allow the panels to interlock when installed. In this way the rectangular panels cover the main surface but leaves spaces where the rectangular panels do not match with the curvature of the tank. These spaces are covered by the trapezoidal panels.

Description:
PRIORITY/CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This Application claims priority to currently pending U.S. Patent Application No. 61/861,212, which is herein incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The presently disclosed and claimed inventive concepts generally relate to storage tanks, and more particularly to a floating insulative cover. 
       BACKGROUND OF THE INVENTION 
       [0003]    Hydraulic fracturing, “frac&#39;ing,” has become increasingly prevalent as the search and demand for additional fossil fuel sources expands. Frac&#39;ing is the fracturing of underground rock through the use of pressurized liquids. In order to release underground fossil fuels high-pressure fluid, often water mixed with sand and chemicals, is injected into a wellbore to create small fractures in the rock. These fractures allow natural gas, petroleum, and brine to travel to the well and be harvested. 
         [0004]    Frac&#39;ing has become popular due to economic benefits. Through the use of frac&#39;ing, wells are able to produce an increased amount of fossil fuels. This allows additional production without necessitating additional drilling operations, additional derricks or additional platforms. 
         [0005]    The process of frac&#39;ing requires large volumes of fluid, such as water, be available to pressurize the wellbore that extends 20,000 feet beneath the surface of the earth. This fluid is typically stored in large above ground tanks. These tanks are often left uncovered with the fluid within the tank exposed to the environment. The tanks are often at temperatures exceeding 90° F. The open top design results in significant loss of fluid through evaporation and also allows for contamination such as birds falling into the tank. 
       SUMMARY OF THE DISCLOSURE 
       [0006]    Disclosed is an insulation system for covering the surface of a liquid in a tank. The system utilizes rectangular panels which have a top and a bottom side as well as a first, second, third and fourth sides that define the perimeter of the top and bottom sides. The first, second, third and fourth sides have a locking rim which is spaced apart from the edge of the top or bottom side. The locking rim engages with locking rims on adjacent panels. In this manner the panels are locked together horizontally to prevent gaps forming in the insulation cover. 
         [0007]    The tanks used to hold the liquid are generally circular in shape. The use of rectangular panels to cover the surface of the fluid results in spaces being created where the rectangular panels do not match the circular edge of the tank. In order to cover the spaces the insulation system utilizes circumferential panels that have an upper and lower side and an inside and outside edge, and a left and right edge. The inside edge is shorter than the outside edge resulting in the left and right edges not being parallel with each other. The circumferential panels&#39; left edge and right edge have locking room similar to that of the rectangular panels. During installation the circumferential panels are oriented so that the inside edge is toward the center of the tank. This allows the circumferential panels to lock together to form a ring extending around the edge of the tank. Further the outside edge of the circumferential panels can be curved in order to match the curvature of the tank. 
         [0008]    The panels are designed to float on the surface of the liquid rather than being attached to the tank. In order to provide a floating and insulating panel, the panels can be made of various materials. In one embodiment the panels are made of foam and are further covered in a hard plastic cover. This hard plastic cover can be molded to include the locking rims that lock the panels together. The locking rims on rectangular panels can be done in several ways. One way is to have two adjacent locking rims oriented in one direction with the other two locking rims oriented in the opposite direction. In this way the panels will all have the same side up when installed adjacent to each other. The upward locking rims of one panel mate with the downward locking rim of an adjacent panel. Alternatively all of the panels can be manufactured to have locking rims facing the same direction. In this embodiment, adjacent panels will be facing in opposite directions. Additionally various sizes and thicknesses of panels can be used with a preferred embodiment being a panel with between one and two inches of foam covering the hard plastic shell. 
         [0009]    The purpose of the Summary of the Invention is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The Summary of the Invention is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 
         [0010]    Still other features and advantages of the claimed invention will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the descriptions of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of an insulative panel in accordance with an embodiment of the inventive concepts. 
           [0012]      FIG. 2  is a perspective view of an insulative panel in accordance with an embodiment of the inventive concepts. 
           [0013]      FIG. 3  is a view from above a section of the tank prior to complete installation of the insulative system. 
           [0014]      FIG. 4  is a perspective view of an insulative panel in accordance with an embodiment of the inventive concepts. 
           [0015]      FIG. 5  view from above a tank incorporating an insulative panel cover in accordance with an embodiment of the inventive concepts. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]      FIGS. 1-5  illustrate an insulation system for covering liquid in a tank. The insulation system utilizes a series of panels. The first panels used are of rectangular panels  12 . Rectangular panel  12  is illustrated by  FIG. 1  and  FIG. 2 . The rectangular panels  12  have a top side  14  and a bottom side  16 . When installed, top side  14  faces upward while the bottom side  16  rests on top of the liquid surface. Top side  14  and bottom side  16  are defined by perimeter  26  that is defined by first side  18 , second side  20 , third side  22  and fourth side  24 . It is preferable that the panel be rectangular in shape but other polygonal shapes can be utilized. In one embodiment top side  14  can be coated with a reflective material to further enhance the thermodynamic properties of the insulative cover. 
         [0017]    The rectangular panel  12  can be made out of various materials that allow the panel to float on the liquid surface while providing insulative properties. A preferable material is foam. The use of foam results in rectangular panels  12  being light weight and low density allowing for flotation as well as providing insulation. The panel can include a hard plastic cover molded around a core that could be many materials such as foam. The hard plastic cover provides for protection during transport as well as prevents the core material from absorbing any liquid. It would also be possible to replace the foam with other insulative and low density material. Examples of this would be to have the panel hollow or inflatable to provide for an air space within the panel. 
         [0018]    First side  18 , second side  20 , third side  22  and fourth side  24  each have a locking rim  28  extending away from the panel. Locking rim  28  creates a locking channel  30  allowing for the panels to be interlocked with adjacent panels having similar locking rims  28  and locking channels  30 . In the embodiment shown in  FIG. 1  and  FIG. 2 , the locking rims  28  on two adjacent sides are oriented in the same direction. This means that two adjacent locking rims  28  would be oriented downward. Meanwhile, the other two sides would have locking rims  28  oriented in the opposite direction. This results in a locking channel  30  that would interlock with a locking channel  30  of an adjacent panel  12  oriented in the same direction. In this manner each panel can be laid in the same orientation and still result in a floating insulative cover that does not drift apart and form gaps that can defeat the insulative properties of the panel. As an alternative, all of the locking rims  28  can be oriented in the same direction with respect to top side  14  and bottom side  16 . In this embodiment the adjacent panels are reversed such that the top side of first panel is exposed to sunlight while the bottom side of all adjacent panels is exposed to the sunlight. While different sizes can be used, a typical size would be a panel that is 2″ of foam, 1/8″ HDPE plastic laminated to the top and bottom of the foam, and cut into 4′×8′ sheets. The plastic can be bent on the edges to form the locking rim  28  or the locking rim  28  can be molded on during manufacturing. 
         [0019]    As shown in  FIG. 3 , the use of the rectangular panels  12  results in spaces  48  being created near the edge of the tank. These spaces are caused by the insulation panels not perfectly aligning with the curvature of the tank. In order to cover the spaces  48 , circumferential panels  32 , shown in  FIG. 4 , are utilized. The circumferential panels  32  have an upper side  34 , a lower side  36 , an inside edge  38 , an outside edge  40 , a left edge  42  and a right edge  44 . The circumferential panels  32  are located near the edge of the tank and float on top of the rectangular panels  12  that have already been installed. The inside edge  38  is positioned toward the center of the tank while the outside edge  40  is positioned near or on the edge of the tank. Left edge  42  and right edge  44  of circumferential panels  32  have locking rim  28 . The locking rim  28  of circumferential panels  32  can be designed similar to the locking rim  28  used on the rectangular panels  12 . The locking rim  28  of circumferential panels  32  also defines a locking channel  30  which allows one circumferential panel  32  to become engaged with an adjacent circumferential panel  32 . This prevents the circumferential panels  32  from moving apart and allowing for gaps in the insulative cover. In one embodiment the locking rims  28  on a circumferential panel  32  are in opposing directions. In this way, each circumferential panel  32  is placed so that the upper side  34  is facing the sun while the lower side  36  is facing downward the tank. It is also foreseeable that the locking rims  28  will be oriented in the same direction so that on one circumferential panel  32  the upper side  34  is facing the sun while adjacent circumferential panels  32  are placed with the upper side  34  facing into the tank. In creating the rectangular panels  12  and circumferential  32 , the locking rim  28  can be formed as a molded part of the plastic cover. 
         [0020]    In order to accommodate the circular path of the tank wall, inside edge  38  is shorter than outside edge  40 . The shorter length of inside edge  38  compared to the length of outside edge  40  creates a trapezoidal shape for the circumferential panels  32 . When installed, this creates a curving shape that is designed to mimic the curvature of the tank. In one embodiment, outside edge  40  can be curved in order to more specifically align with the edge of the tank. 
         [0021]      FIG. 5  shows a fully installed insulation system  10 .  FIG. 5  shows the rectangular panels  12  having interlocked with each other and circumferential panels  32  also interlocked to form a ring around the edge of the tank. The rectangular panels  12  float on top of the liquid within the tank while the circumferential panels  32  rest on top of the rectangular panels  12 . Circumferential panels  32  do not require fasteners to hold in place but are preferably held in place by friction with the rectangular panels  12 .  FIG. 3  shows a section of tank with the rectangular panels  12  installed. Near the edge of the tank, due to the curvature of the tank wall, spaces  48  are created. These spaces circumferential panels  32  are designed to cover and insulate.