Tank liner

Description

FIELD OF THE INVENTION

The invention relates generally to chemical tank liners. More specifically it relates to an apparatus and method of use of a flexible tank liner for use in a transportable tank or a stationary tank.

BACKGROUND AND SUMMARY

Tanks can be used to haul or store liquids, including chemicals which may be toxic, non-toxic, caustic, or corrosive. Tanks are usually formed from stainless steel or PVC. Some stainless steel tanks include a fiberglass liner to prevent corrosive polyvinyl chloride chemicals from eating way the stainless steel tank. Fiberglass liners may be difficult to install and do not usually allow for changing the chemicals stored within from one type of chemical to another. PVC tanks lack the structural support provided by a stainless steel tank.

In accordance with one aspect of the present invention, there is provided a tank for storage of fluids, comprising a body, at least one flange, a liner body, an air permeable support structure and a plurality of evacuation members. The body has an outer wall and an inner wall, the inner wall defines an interior region. The at least one flange receives a vacuum source to pressurize the interior region. The liner body has an outer surface, the liner body is positioned within the interior region of the body. The air permeable support structure is positioned between the liner body and body interior region. The plurality of evacuation members are positioned on the inner wall.

In accordance with another aspect of the present invention, there is provided an installation method for a liner in a tank that has a body with an outer wall and an inner wall defining an interior region. The method comprises the steps of providing an evacuation member along the inner wall, positioning the liner within the interior region, and evacuating the air from between the inner wall and the liner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a front side view of a tank attached to a vehicle;

FIG. 1B is a cross section view showing an interior region within the tank without a liner;

FIG. 2 is a cross section view of the tank taken along the line 2-2 of FIG. 1A showing an interior of the tank having a liner, a plurality of evacuation members, and an air permeable support structure;

FIG. 3 is a cross section view similar to FIG. 2 and taken along the line 3-3 of FIG. 1A;

FIG. 4 is a front view of an intersection of the plurality of evacuation members;

FIG. 5 is a cross section view similar to FIG. 2 and taken along the line 5-5 of FIG. 1A;

FIG. 6 is a cross section view similar to FIG. 2 and taken along the line 6-6 of FIG. 1A;

FIG. 7 is a front perspective cutaway view of a portion of an alternative embodiment of a tank showing a plurality of tubing used as a plurality of evacuation members;

FIG. 8 is a front perspective cutaway view of a portion of an alternative embodiment of a tank similar to FIG. 7 only showing a plurality of channels used as a plurality of evacuation members;

FIGS. 9-12 are perspective views illustrating a method of installation of the liner of all the previous embodiments; and

FIG. 13 is a perspective view showing additional components for changing the chemical stored in the tank.

DETAILED DESCRIPTION OF THE DRAWINGS

The embodiments of the present invention described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of the present invention.

Referring now to FIG. 1A, there is shown a tank 10 attached to a vehicle 12 for transport of chemicals or liquids from a first destination to at least a second destination. Tank 10 and vehicle 12 are supported by a plurality of wheels 14. Tank 10 is similar to a conventional tanker trailer including a body 16, a plurality of outer ribs 18, a rear walkway assembly 20, a plurality of flanges 22, an at least one manway 24 and a vacuum flange 26. If no vacuum flange is provided with the tank a flange should be added. The at least one manway 24 could also be an additional flange 22. Vacuum flange 26 is configured to receive a vacuum source for pressurization of body 16. Alternatively, tank 10 could be a stationary tank, a tanker ship, an airplane tanker, or any other conventional tank for transporting fluids.

As shown in FIG. 1A, body 16 includes an outer wall 27 having an outer rear portion 28, an outer central portion 30, and an outer front portion 32. Body 16 further includes an inner wall 34 defining an interior region 36, as shown in FIG. 1B. In one embodiment, body 16 is stainless steel. In other embodiments, body 16 is fiberglass, other steels, metals, or plastic. Additionally, body 16 could be a conventional tank body with a conventional fiberglass liner already in place.

As shown in FIGS. 2-3, tank 10 further includes a liner 38. Liner 38 is configured for placement within interior region 36 and is sized to substantially the same dimensions as the interior region. In alternative embodiments, a plurality of liners is provided of different sizes but their combined size is substantially the same dimension as the interior region.

Liner 38 includes a liner body 40, a plurality of evacuation members 42, and an air permeable support structure 44. In one embodiment, liner body 40 is formed from flexible ¼ inch PVC. In other embodiments, liner body 40 is formed from Kynar® manufactured by Elf Atochem North America, Inc., plastic, or any other flexible material conventionally used in transportation or storage fluids or liquids including chemicals such as bleach, hydrochloric acid (HCl), caustic soda, or any other liquid chemical. Any size liner will work so long as it maintains some level of flexibility. Liner 38 could be formed as a single piece with evacuation members attached by adhesive or welding to liner 38 or integrally formed with liner 38. Additionally, liner body 40 could be a single piece of material formed into the desired shape or it could be multiple pieces welded or adhered together to form the desired shape.

Evacuation members are attached to interior region 36 with a plurality of attachment members (not shown). In one embodiment, attachment members are tape. In other embodiments, attachment members are glue, clips, bolts, staples, screws, or any conventional adhesive material or conventional attachment material. In one embodiment, air permeable support structure 44 is a synthetic wool blanket which extends the length of body 16. In other embodiments, air permeable support structure 44 is wool, cotton, or any other air permeable blanket like structure. Additionally, air permeable support structure 44 could cover all or at least a larger portion of inner wall 34 or could be removed and replaced with additional evacuation members 42.

The plurality of evacuation members 42 include a plurality of longitudinal members 46 configured to run at least in portion of the length of interior region 36 perimeter (see FIG. 2), a plurality of end members 47 located near front portion 32 and rear portion 28 and configured to extend from air permeable support structure 44 to an upper portion 50 of interior region 36, and a plurality of vertical members 48 located approximately at every rib 18 and configured to extend from air permeable support structure 44 to upper portion 50 (see FIG. 3). In one embodiment, the plurality of evacuation members 42 is ¼ inch tubing formed from PVC. In other embodiments, evacuation members 42 are any size tubing such as 1/16 inch to 2 inch tubing. Additionally, any material could be used for the evacuation members such as metal, plastic, or glass. An additional embodiment of evacuation members 42 is described below with reference to FIG. 8.

Referring now to FIGS. 2 and 4, longitudinal members 46 intersect vertical members 48 and end members 47 at a plurality of locations 52 in interior region 36. FIG. 4 shows one such location 52 where one longitudinal member 46 intersects one vertical member 48. As shown in FIG. 4, longitudinal members 46 and vertical members 48 are segmented. The segments of members 46 and 48 form a T-shape where members 46 and 48 intersect at each location 52. An opening 54 is provided at the intersection of members 46 and 48. Opening 54 is a space between ends of segments of each member 46 and 48. Opening 54 allows evacuating air to pull through opening 54 into members 46 and 48 for removal through vacuum flange 26. In other embodiments, opening 54 could be replaced or used along members 46 and 48 if members 46 and 48 were perforated.

A cross section of vacuum flange 26 is shown in FIG. 5. Vacuum flange 26 includes a cover 56, a vacuum flange body 58, and a vacuum opening 60. Vacuum flange body 58 may be a portion of body 16. Vacuum opening 60 is of sufficient size to receive a vacuum hose (not shown) for removing air from between liner body 40 and inner wall 34. Liner body 40 is continuous around vacuum opening 60. As described in detail below, a vacuum is applied through vacuum opening 60 to remove substantially all the air from between inner wall 34 and liner body 40. Vacuum flange body 58 and cover 56 may be attached via bolts, screws, welding, or any other conventional sealing of a flange on a tank. A cross section of manway 24 is shown in FIG. 6. Manway 24 includes an upper portion 66, a manway body 68, a manway opening 70, and a hatch opening 71. Manway body 68 may be a portion of body 16. Upper portion 66 includes a hatch assembly 72 including a hatch 74, a hinge 76, a locking member receiver 78, and a locking member (not shown). The locking member is configured to secure hatch 74 in the closed position. Liner body 40 includes a hatch portion 80, a manway portion 82, and a main body portion 84. Manway portion 82 includes an upper manway portion 86 and a lower manway portion 88. Manway body portion 68 is configured to extend outside manway opening 70. Upper manway portion 86 is configured to extend outside hatch opening 71. Upper manway portion 86 extends manway portion 82 creating an air-tight seal when hatch 74 is in the closed position. Lower manway portion 88 and main body portion 84 provide a seal when upper portion 66 is attached to manway body 6. Manway body 68 and upper portion 66 may be attached via bolts, screws, welding, or any other conventional sealing of an upper portion on a tank. Details of manway 24 can be applied to flanges 22. When referring to flanges 22 a longer flange body portion and different size flange covers or flange openings may be necessary. Additionally, hatch assembly 72 may not be necessary for use with flanges 22.

An alternative embodiment of a tank 10′ is shown in FIG. 7. Tank 10′ is a stationary tank. Tank 10′ is similar to tank 10 of the previous embodiment. Tank 10′ is shown with a manway 24 and may include a plurality of flanges and vacuum flanges not shown. Similar reference numerals are used showing a plurality of evacuation members 42 having a plurality of longitudinal members 46 and a plurality of vertical members 48. No air permeable support structure is provided but one could be used in the stationary tank 10′ embodiment. A liner 40, as described above, is usable with tank 10′. See above for additional description of tank 10 and liner 40, all of which is applicable to tank 10′.

FIG. 8 shows an additional embodiment of a tank 10″. Tank 10″ could be used in either a stationary tank or a transport tank as described above. Tank 10″ is shown with a manway 24 and may include a plurality of flanges and vacuum flanges not shown. Tank 10″ further includes a body 16″. Body 16″ includes an outer wall 100 and an inner wall 102 defining an interior region 104. A plurality of evacuation members 106 are provided within interior region 104. In this embodiment, inner wall 102 is covered with a conventional fiberglass liner. The plurality of evacuation members 106 are formed, etched, or carved into the fiberglass liner to create a similar pattern as the plurality of evacuation members 42 described above with reference to the first embodiment tank 10. A liner (not shown) is then placed within interior region 104 similar to liner 40 described above, only with evacuation members 106 formed into the fiberglass liner. In alternative embodiments, evacuation members 106 could be the same as described above only placed over the fiberglass liner.

A method of installation of liner 40 is illustrated in FIGS. 9-12. As shown in FIG. 9, liner 40 is stored in a folded arrangement or position. To install liner 40, an installer (not shown) spreads air permeable support structure 44 along the bottom surface of interior region 36, see FIG. 2. Next, the installer installs the plurality of evacuation members 46, see description above. Next, liner 40 is inserted through manway 24 while in the folded positioned and unfolded with main body portion 84 and vacuum body portion 64 facing upwards (see FIG. 10). All of the flange portions are removed for simplicity of description of this method. Next, liner 40 is filled with air or a fluid to “pop” the liner into the proper shape. Because liner 40 is cut to the approximate size of interior region 36 it will press against the sides of inner wall 34. An installer pulls or pushes main body portion 84 and vacuum body portion 64 to their positions, as described earlier. All flanges 22 and manway 24 are closed sealed to liner 40. A vacuum is applied through vacuum flange 26 to remove the remaining air from within the interior region 36. As described above, air permeable support structure 44, and the plurality of evacuation members 42 are already installed. When the vacuum is applied through vacuum flange 26 air passes from around liner 40 through the air permeable support structure 44 and the plurality of evacuation members 42. As substantially all of the air is removed from between liner 40 and inner wall 34, the liner seals itself against inner wall 34. Once all the air is removed, vacuum flange 42 is closed and the vacuum is removed. Manway 24 may now be opened. The installer opens manway 24 and inspects that liner 40 is positioned tightly against inner wall 34. With the air removed from between inner wall 34 and liner 40, liner 40 is sealed against inner wall 34 without the use of adhesives. The tank is now ready for use and can receive chemicals and be pressurized similar to normal transportation tanks.

In alterative installation, pieces of the liner material are inserted in the tank. The evacuation members are installed as described above. Next, the liner body is formed inside the tank by welding and cutting the pieces where necessary.

If the liner should fail during use, such as tear, develop a crack, or fail in another way, it may be noticeable by simply checking the manway between uses or after a certain number of uses. A system could be developed to allow easy compliance with Department of Transportation liner requirements. Replacement of liner 40 if necessary by simply removing a defective liner 40 and replacing it with a new liner following the steps described above.

As shown in FIG. 13, a neutralizing tank 200 is provided for use with a pump assembly 202 and tank 10. Pump assembly 202 may be integral with tank 10 or may be a stand alone unit. Neutralizing tank 200 includes a tank body 204, a tank valve 206, a pump valve 208, a tank hose 210, and a pump hose 212. A neutralizing solution 214 is provided within tank body 204. Neutralizing solution 214 is pumped into tank 10 after all fluid is removed from tank 10. Neutralizing solution 214 is sprayed on liner body 40 to neutralize the chemical previously carried in the tank so that a different chemical can be used. Examples of neutralizing solution 214 include Sodium Thio Sulfate to neutralize chlorine and Soda Ash to neutralize most acids. Additional neutralizing solutions known in the art for neutralizing various chemicals are envisioned within the scope of this application.

Preferably, instructions for the assembly, installation, and/or use of tank 10 are provided with tank 10 or otherwise communicated to permit a person or machine to assemble, install and/or use tank 10. Such instructions may include a description of any or all portions of tank 10 and/or any or all of the above-described assembly, installation, and use of tank 10 or components of tank 10. The instructions may be provided on separate papers and/or on the packaging in which tank 10 is sold or shipped. These instructions may also be provided over the Internet or other communication system. Furthermore, the instructions may be embodied as text, pictures, audio, video, or any other medium or method of communicating instructions known to those of ordinary skill in the art. In normal use, tank 10 is filled with a first chemical, the first chemical is transported from a first location to a second location, tank 10 returns to a neutralizing location, any remaining first chemical is removed from tank 10, and neutralizing solution 214 is added. After tank 10 is neutralized, tank 10 is rinsed with water or another inert solution, an a second chemical may be added to tank 10.

While this invention has been described with specific embodiments thereof, alternatives, modifications and variations may be apparent to those skilled in the art. The device could be modified for use in a transmission. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.