Abstract:
This specification relates to systems and methods to insulate components of industrial infrastructure, such as tank systems and valve boxes used in association with oil wells. According to some implementations, a system includes a component to contain an outflow associated with industrial infrastructure; a foam arranged to insulate an exterior area associated with the component; a moisture barrier arranged to protect the foam; and a support structure to protect the foam from the weight of the component.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. Pat. No. 9,702,631, issued Jul. 11, 2017, which claims the benefit of priority from U.S. Provisional Application Ser. No. 61/430,540, filed Jan. 6, 2011 and entitled “SYSTEMS AND METHODS TO INSULATE COMPONENTS OF INDUSTRIAL INFRASTRUCTURE”, each of which is hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    This specification relates to systems and methods to insulate components of industrial infrastructure, such as tank systems and valve boxes used in association with oil wells. 
         [0003]    The main problems with insulating materials are moisture saturation and moisture migration. Moisture saturation reduces the effectiveness of the insulation. In extreme cases, moisture causes some insulators to become conductors. In other cases moisture migrates, which can cause a host of other problems such as mold growth and propagation as well as a conduit for bacteria and virus transmission. There is structural degradation issues associated with moisture against metal used in components of industrial infrastructure. 
       SUMMARY 
       [0004]    This specification describes systems and methods to insulate components of industrial infrastructure, such as tank systems and valve boxes used in association with oil wells. 
         [0005]    In general, one or more aspects of the subject matter described in this specification can be embodied in a system that includes a component to contain an outflow associated with industrial infrastructure; a foam arranged to insulate an exterior area associated with the component; a moisture barrier arranged to protect the foam; and a support structure to protect the foam from the weight of the component. 
         [0006]    Particular embodiments of the subject matter described in this specification can be implemented to realize one or more of the following advantages. A polyisocyanurate (PIR) foam and polyurea insulated system for a component (e.g., a tank or a valve box) can prevent the problems associated with traditional insulating materials by making a water proof system as tight as and similar to the way a roofing system keeps moisture from penetrating under layers. The PIR foam can provide excellent performance due to its temperature ratings for hot and cold, as well as its ability to resist fire and smoke propagation. The polyurea can be blended for a combination of UV resistance and elongation properties. Depending on the calculated Coefficient of thermal expansion or contraction for the given component (e.g., a tank or a valve box), the polyurea can be matched up to 600% elongation. The poly can be mixed with the entire pantone chart of pigments giving it the ability to either stand out brightly or be less obvious and blend into its surroundings. Moreover, the component (e.g., a tank or a valve box) may be above ground or below ground. 
         [0007]    Another advantage of the described insulation methods and practices can be a significant reduction of the carbon footprint of industrial infrastructures. The highly effective insulation can reduce the thermal effects, such as heat loss, and can reduce the amount of energy required to keep the contents (e.g., fluids) of the components of industrial infrastructures at operating temperature. 
         [0008]    The details of one or more embodiments of the subject matter described in this specification are set forth below. Other features, aspects, and advantages of the invention will become apparent from the description, the drawings, and the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  shows an example of a pre-insulated tank system. 
           [0010]      FIG. 2 a    shows another example of a pre-insulated tank system. 
           [0011]      FIG. 2 b    shows a detail view of a core tank, insulation layers, support structures, mesh, and coating. 
           [0012]      FIG. 3  shows an example of a pre-insulated tank infrastructure. 
           [0013]      FIG. 4  shows an example of a pre-insulated valve box system. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    PIR Insulated Tank Systems with polyurea moisture barrier exterior: 
         [0015]    As noted above, tanks can be insulated using PIR foam and polyurea preventing undesired thermal effects (e.g., heat loss or heat gain). Some enhanced options for these tanks are the use of a stainless steel heat exchanger located internal to the tank, attached to the tank wall. The insulated tank system is applicable to static tanks such as American Petroleum Institute (API) tanks for fuel and industrial processes, American Society for Testing and Materials (ASTM), National Insulation Association (NIA), or American Society of Mechanical Engineers (ASME) compliant pressure vessels, heaters used in the oil and gas industry, water knock outs, condensate tanks, produced water tanks (e.g., from oil and gas wells) and high paraffin or tar sand oil applications, and food grade storage tanks as well as tanker cars and rail cars. 
         [0016]    For example, in oil and gas wells, produced water can be the result of water being eliminated from product storage tanks and pipelines, which can be contaminated to a level, for example by paraffin oil buggering up the treatment solution, where it cannot be readily re-injected into the ground and therefore must go through a treatment process. The described pre-insulated tank can prevent this contamination by taking advantage of thermo dynamic processes, which separate the paraffin oil, entrained solids, from the fracturing process and salts. The result can be clean water that is ready for re-injection into the ground instead of relying on evaporation. 
         [0017]    The drawings described below show various views of a pre-insulated tank design, a tank external coat banding, and support structure (e.g., dowel rods or stand-offs) close up. Pre-insulated tanks, as shown, are water proof and can be transported. The support structures can be insulated and hold the tank from crushing the insulation (e.g., HiTherm HT-300 or HT-450 from HiTHERM, LLC of Cerritos, Calif.). The coating or outer jacket can be Hi-therm polyurea, a blended base coat of aromatic and a top coat (UV stable) of aliphatic polyurea. 
         [0018]      FIG. 1  shows an example of a pre-insulated tank system  100 . The pre-insulated tank system  100  can include a core tank  110 , a heat exchanger  120 , an insulation layer  130 , a mesh  140 , a coating  150 , and support structures  160 . The core tank  110  can be a standard tank commonly used within the industry (e.g., made out of steel or fiberglass). In some implementations, the inner surface of the core tank  110  can be coated with polyurea (e.g., an aromatic blend that is designed specific to the liquid to be stored in the tank.) The support structures  160  can be attached to the tank, for example by gluing or welding processes, and protrude through the insulation layer  130  until flush with, or slightly elevated (e.g., 80 mil) above, the outer surface of the insulation layer  130 . The measurement unit ‘mil’ or ‘thou’, as used throughout the specification, is a unit of length equal to 0.001 inch (thousandth(s) of an inch). 
         [0019]    These support structures  160  can be insulated stand-offs or dowel rods. The support structures  160  can provide structural integrity to the insulation layer  130  and coating  150 , preventing damage to the insulation layer  130  during transport of the pre-insulated tank system  100 , even at highway speeds or off road deliveries. By integrating the support structures  160 , the core tank  110  can be insulated before shipping, reducing (if not eliminating entirely) any special equipment required for the transport. Also, because the support structures  160  are integrated (e.g., permanently) no re-insulation of the tank may be necessary if the tank is moved, after being installed at one location, to another location. 
         [0020]    Therefore, the insulation layer  130  in combination with support structures  160  can provide a time and cost efficient solution. Moreover, the tanks can be assembled into a tank battery and become operational quickly. 
         [0021]    In some implementations, the support structures  160  can be attached with PIR foam or construction adhesive such as elastomeric polymers. The foam PIR can be applied to the core tank  110 , and a tool can be used to make cut outs in the foam that are slightly smaller than the outer diameter of the support structures  160 . The support structures  160  can be dabbed with a fixadent, and set into place. The support structures  160  can be made from insulating material PIR in a liquid form, lightly expanded to maintain insulating properties and proportional strength characteristics. 
         [0022]    In some implementations, the diameter of the support structures can be 2 inches, but may be increased or decreased based on tank diameter and weight. These support structures can be slightly longer (e.g., 80 mil) than the insulating layer thickness and serve as a depth gauge for the coating process. The coating  150  can completely cover the support structures, ensuring proper coating thickness. The support structures  160  can be integrated independent of the application of a mesh  140 , and may not be visible with or without the mesh. 
         [0023]    As described above, the insulation layer  130  can be PIR foam. The insulation layer  130  is wrapped around the core tank  110 . Any desired thickness or number of layers can be used to create the insulation layer  130 , depending on the requirements of the particular installation. The required thickness of the insulation layer can be determined by heat loss characteristics of the tank system and the desired maintained temperature for a liquid with a defined specific gravity and the specified heat source for British Thermal Units (BTUs). In some implementations, the thickness of the insulation layers can be 2-3 inches. 
         [0024]    In addition, a mesh  140  can be wrapped around the insulation layer  130 . The mesh  140  can hold the insulation layer  130  in place and act as a depth gauge for the coating  150 . The mesh  140  can also act as reinforcement for the insulation layer  130 , for example, to prevent damage to the insulation layer  130  if maintenance personnel step onto the tank surface. The mesh  140  can be industrial netting that is extruded, oriented, or made from various materials depending on the application and strength required, such as polymesh (e.g., polypropylene or polyethylene), cloth, hemp, and in some cases metal. In some implementations, the mesh  140  can be chicken wire mesh as shown in  FIG. 1 . 
         [0025]    The coating  150  can be added around the insulation layer  130  or the mesh  140  and completely cover the pre-insulated tank, including the support structures  160 , in a continuous layer with the least number of breaks (e.g., for fluid flow connections). The coating  150  can protect the insulation layer  130  from exposure to environmental conditions (e.g., water, UV, etc.). As described above, the coating  150  can be Hi-therm polyurea, a blended base coat of aromatic and a top coat (UV stable) of aliphatic polyurea. For example, the base coat can be an aliphatic or blended aromatic 50 mil coat, plus 30-50 mil of an aliphatic top coat to resist UV fading of colored tanks. In some implementations, the thickness of the complete coating  150  can be 80-100 mil or more. In some implementations, the coating  150  can act as a moisture barrier and can be wrapped or sprayed onto the insulation layer  130  or mesh  140 . 
         [0026]    In some implementations, the coating  150  can be added by spray on application, for example, the HiTherm HT-300 and HT-450. Other similar spray foam techniques can also be used in some implementations. For example, PUR or polyurethane foam in sheet stock or spray foam can also be used in some implementations. There are other products in board stock such as phenolic and polyisocyanurate (PIR) foam from Johns Manville of Denver, Colo., or extruded polystyrene foam (XPS) from The DOW Chemical Company of Midland, Mich. (blue or green board) or XPS Pink Board from Ownens Corning of Toledo, Ohio. 
         [0027]    In some implementations, the tank  110  can be equipped with a heat exchanger  120 . The heat exchanger  120  can be a stainless steel heat exchanger, for example, implemented as a spiral flex pipe as shown in  FIG. 1 . The heat exchanger  120  can be added to the interior of the core tank  110  to deliver the amount of heating necessary to keep the liquid contained in the tank  110  at acceptable temperatures. For example, the heat exchanger  120  can be a 63 mm or nearly 2.5″ stainless steel spiral flexible pipe/hose×400 feet long, available from Brugg Pipesystems of US-Rome, Ga., or from Rovanco Pipe Systems of Joliet, Ill. The heat exchanger  120  can start and end at flanges incorporated in the wall of the core tank  110 , usually within about 2 to 4 feet of each other vertically. The integration of the heat exchanger  120  can eliminate the use of standard bayonet style electric heater or gas fire tube heaters and can, for example, replace a burner tube, allowing a mixed fuel source for heating the tank, which includes solar, natural gas (dry gas or wet gas) and other fuels such as low emitting bio-fuels. Moreover, the use of a spiral flex pipe, as opposed to corrugated pipe, can result in less breakage (e.g., from bending) and better heat transfer. Therefore, with the internal heat exchanger  120  described above, tanks can be grouped onto a central heating system and replace individual heaters, which otherwise may be required for each tank. 
         [0028]      FIG. 2 a    shows another example of a pre-insulated tank system  200  and  FIG. 2 b    shows a detail view of the core tank, insulation layer, support structures, mesh, and coating. 
         [0029]    The tank system  200  can include a core tank  210 , heat exchanger  220 , support structures  230 , insulation layers  240 , a mesh  250 , and a coating  260 . The heat exchanger  220  can be attached to the interior of the core tank  210  as described above with respect to  FIG. 1 . The support structure  230  can be stand offs or dowel rods glued or otherwise attached to the outer surface of the core tank  210 . 
         [0030]    In some implementations, the top of the core tank  210  can be arranged in a conical shape. The build process of the top of the tank can be identical to the sides and bottom of the tank. As described above, the core tank  210  can be covered with insulation layers  240  (e.g., PIR foam), a mesh  250  and a contiguous layer of coating  260  (e.g., polyurea.) In some implementations, a heat exchanger  220  can be integrated in the core tank  210  as described above. When used in the oil and gas industry, the integration of the heat exchanger  220  can provide that the top of the tank does not build up with paraffin that can trap gases that may have to be relieved via a roof vent, which may cause a dangerous situation. The use of the heat exchanger  220  can also ensure a proper thermodynamic process causing the liquids heated on the outer surfaces to flow inward towards the middle of the core tank  210 , preventing the collection of paraffin on the tank walls. 
         [0031]    In some implementations, the support structures  230  are arranged in patterns as shown in  FIG. 2  to reduce the number of support structures  230  required and still provide the required structural integrity for transportation of the pre-insulated tank  200 . The support structured  230  can be arranged such that the tank system  200  can be transported in a horizontal position. The size and quantity of the support structures  230  can be determined based on the size and weight of the tank system  200 . 
         [0032]    In some implementations, the support structures  230  extend from the outer surface of the core tank  210  to the outer surface of the insulation layers  240 . Therefore, the length of the support structures  230  can be similar to the thickness of all insulation layers  240  combined. The support structures  230  can be completely covered with the mesh  250  and/or coating  260 , and therefore may not be visible in the final product. 
         [0033]    The insulation layers  240  can be wrapped around the core tank  210  as described above. The desired insulation of the core tank  210  can be achieved by using any desired number of insulation layers and insulation material thicknesses, depending on the particular installation. For example, in  FIG. 2 , the pre-insulated tank system  200  includes two insulation layers  240 . The insulation layers  240  can be PIR foam typically available in sheet stock (e.g., 9-12 inches in width and 3-6 feet tall). In some implementations, the first insulation layer (i.e., inner layer) and the second insulation layer  240  (i.e., outer layer) can be each 1-2 inches thick for a total thickness of 2-4 inches (3 inches is most typical for applications under  200 F.) 
         [0034]    The insulation layers can be structurally reinforced by adding a mesh  250  and protected by adding a coating  260  as described above. As described above, the mesh  250  can be industrial netting, for example polymer (e.g., Industrial Netting Product OF-1581) or metal (e.g., chicken wire) based dependent on the desired strength. In some implementations, the coating  260  can be a polyurea coat, typically 80-100 mil thick, where the coating can be applied in several layers, for example, an inner layer can be aromatic (e.g., 50 mil) and an outer layer can be aliphatic (e.g., 30-50 mil) if color fade is an issue, or the complete layer can be aromatic (e.g., 100 mil) if color fade is not an issue. 
         [0035]      FIG. 3  shows an example of a pre-insulated tank infrastructure  300 . The pre-insulated tank infrastructure  300  can include several pre-insulated tanks  310  (e.g., a tank battery) and a platform  320 . The pre-insulated tanks  310  can be configured as described above, for example, by including a core tank  330 , a heat exchanger  340 , support structures  350 , insulation layers  360 , mesh  370 , and coating  380 . In some implementations, the cores of the pre-insulated tanks  310  can be made of steel, fiberglass, or plastic, and the inside surface of the pre-insulated tanks  310  can be lined with polyurea. The heat exchanger can be a stainless steel flexible tube (e.g., Niroflex or Spiraflex spiraled stainless steel from Brugg Rohrsystem AG of Kleindoettingen, Switzerland). The insulation layers can be PIR foam, such as HT-300 or HT-450, which is typically used in high temperature applications (e.g., when Therminol or other higher temperature transfer fluids are used). 
         [0036]    The platform  320  can include one or more walkways and can be configured to provide access to the pre-insulated tanks  310 , for example, for maintenance purposes. The platform  320  and all of its components can be galvanized to provide resistance to corrosion, particularly in Hydrogen Sulfide (H2S) environments. In some implementations, the platform  320  provides sufficient structural integrity such that the platform  320  is a self supporting and standing walk way and stair system, where attachment to the pre-insulated tanks  310  is not necessary. In some implementations, a safety band around a pre-insulated tank  310  may be attached to the platform  320 , without penetrating the coating  380 . Therefore, the protective coating  380  of the pre-insulated tanks  310  is not unnecessarily protruded by attachment hardware or structures, possibly exposing the insulation layers and core tank to moisture or other environmental conditions. In some implementations, the platform  320  can be installed in 20 foot sections, is mobile with the tank battery, and can be disassembled quickly and reassembled with every move of the tank battery. 
         [0037]    PIR Insulated Valve Box Systems with polyurea moisture barrier exterior: 
         [0038]    As noted above, valve boxes can be insulated using PIR foam and polyurea, preventing undesired thermal effects (e.g., heat loss or heat gain). These valve boxes can perform on average 300% more efficiently than non-PIR large pipe valve boxes. Moreover, some enhanced options for the valve box is the use of a leak detection system located internal to the valve box, with a solar battery charger alarm system attached to the valve box wall. This can send a contact closure to a relay turning on a pole mounted light-emitting diode (LED) light indicator all the way to a wireless modem sending a signal to a secure web server allowing an email to be sent or a text to a cell phone or pager. 
         [0039]    The insulated valve box system is applicable to valve boxes such as API valve boxes for fuel and industrial processes, food process technology, biotech, pharmaceuticals, hydronic heating and cooling system systems and other thermal process applications. Pre-insulated heat traced valve boxes, as described, are water proof and can be transported without risking damage to the insulation material. Moreover, pre-insulated valve boxes can be light weight and can be safely opened and closed (e.g., by one person) preventing entrapment in a confined space and significantly reducing the risk of bodily injury. 
         [0040]      FIG. 4  shows an example of a pre-insulated valve box system  400 . The insulated valve box system can include a valve box top  410 , a valve box bottom  420 , carrier pipes  430 , heat trace pipes  440 , pipe insulation layers  450 , outer pipe jacket  460 , and a fluid capture bag  470 . In some implementations, the valve box top  410  and valve box bottom  420  can be made from solid PIR layers (e.g., 3 inches thick or more) and can be covered with mesh and coating (e.g., polyurea) as described above with respect to tank systems. In some implementations, the valve box top  410  and valve box bottom  420  and/or the pipe insulation layers  450 , can be reinforced with a mesh similar to the tank system described above with respect to  FIGS. 1 and 2 . 
         [0041]    The carrier pipes  430  can be used for fluid and gas transfer, for example, in food processing, hydronic heating, hydraulic fracturing fluid or frac fluid, and petroleum products such as high paraffin oils. In some implementations, the carrier pipes can be made of cross-linked polyethylene (PEX), steel, or fiberglass. The heat trace pipes  440  can be used to transfer fluid at desired temperatures to provide heating or cooling for the carrier pipes  430 . The carrier pipes  430  and heat trace pipes  440  can be covered by pipe insulation layer  450 . The pipe insulation layers  450  can be made of PIR (e.g., HT-300 or HT-450.) The outer pipe jacket  460  can cover the pipe insulation layers  450 . In some implementations, the outer pipe jacket  460  can be made from galvanized steel, PVC, polyethylene, or polyurea. 
         [0042]    The fluid capture bag  470  can be integrated into the pre-insulated valve box system  400  to catch leaks that may occur, for example, when the valves or pipes in the valve box are worked on. A drain in a low point of the valve box system  400  can direct spilled fluids to the fluid capture bag  470 . In some implementations, the fluid capture bag  470  can be configured to collect sunlight to keep the collected liquids warm during the day. A quick disconnect can be implemented, such that replacement of the fluid capture bag  470  can be quickly performed as necessary. A clear top layer in the valve box top  410  can be integrated, for example, to allow maintenance personnel to observe fluids collecting in the valve box system and assess whether servicing may be required. 
         [0043]    While this specification contains many implementation details, these should not be construed as limitations on the scope of the invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments of the invention. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination. 
         [0044]    Thus, although particular embodiments of the invention have been described, other embodiments would be apparent to one of ordinary skill in the art and are within the scope of the following claims.