This disclosure relates to the field of containment systems for liquid storage facilities and in particular a portable containment system for temporary use.
Protection of the environment from spilled hazardous liquids such as contaminated water or the like is provided by containment structures. In a typical situation the hazardous liquid is located in a primary vessel or container, and then the containment structure surrounds the primary vessel and contains any liquid that might spill from the primary vessel.
Such a containment structure is disclosed for example in U.S. Pat. No. 5,689,920 to Hallsten which describes a modular containment system where a series of berm members are interlocked together to form a desired containment perimeter. A liner of flexible plastic material is laid over the containment area, and extends up over the top of the perimeter structure and is secured to the top of the perimeter structure. U.S. Pat. No. 8,636,445 to Williams and U.S. Pat. No. 7,614,825 to Kroger disclose similar containment structures with portable frame sections supporting a liner.
Often such containment structures are required for temporary use. The containment structure is set up at a work site, for example a petroleum well, and then the primary vessel is placed inside the containment structure. Often the primary vessel will be a tanker trailer on wheels such as disclosed by Williams, thus requiring the containment structure to have a wall that can be erected after the trailer is driven into the structure.
U.S. Pat. Nos. 5,762,233 and 6,880,720 to Van Romer disclose a portable containment structure where leg assemblies support the edges of the liner vertically to form a containment area within the vertical edges of the liner. The leg assemblies are shown in various forms inside and outside the containment area, and have a first vertical leg attached to the edge of the liner. A second inclined leg is hinged to the top of the first leg and is movable from a folded position, generally flat against the first leg, to an operating position supporting the first leg in the vertical position. A third leg is hinged to the bottom of the second leg, and maintains the second leg in the inclined position.
The present disclosure provides a portable containment system that overcomes problems in the prior art.
In a first embodiment the present disclosure provides a portable containment system for transporting to a desired location for temporary deployment on a surface. The system comprises a flexible liner sheet with first and second side edge portions and first and second end edge portions. A plurality of side leg assemblies is attached to the side edge portions of the liner sheet, and a plurality of end leg assemblies is attached to the end edge portions of the liner sheet, each leg assembly consisting of two legs connected by a fabric hinge and movable from a collapsed transport position where the legs of each leg assembly lie substantially flat against the liner sheet, to an upright operating position where bottom ends of the legs rest on the surface separated by a base distance, and the legs slope upward toward each other to form a triangle. The corresponding edge portion of the liner sheet is attached to the leg assemblies in proximity to a top of the triangle. The bottom ends of the leg assemblies on each edge of the liner sheet are connected to a flexible leg sheet configured such that when the bottom ends of the legs are separated by the base distance, the leg sheet is tight between the bottom ends of the legs, and such that the leg assemblies are substantially evenly spaced along each edge portion of the liner sheet when the leg sheet is tight.
Moving all the side and end leg assemblies to the operating position supports the edge portions of the liner sheet in a raised position sloping upward from the surface at an angle less than about 75 degrees, such that a containment area is formed inside the sloping edge portions of the liner sheet.
In a second embodiment the present disclosure provides a method of providing a temporary containment system for a tanker vehicle on a surface at a work site. The method comprises providing a flexible liner sheet with first and second side edge portions and first and second end edge portions; attaching a plurality of side leg assemblies to the side edge portions of the liner sheet, and attaching a plurality of end leg assemblies to the end edge portions of the liner sheet, each leg assembly consisting of two legs connected by a fabric hinge and movable from a collapsed transport position where the legs of each leg assembly lie substantially flat against the liner sheet, to an upright operating position; wherein the bottom ends of the leg assemblies on each edge portion of the liner sheet are connected to a flexible leg sheet configured such that when the bottom ends of the legs are separated by a base distance, the leg sheet is tight between the bottom ends of the legs, and such that the leg assemblies are substantially evenly spaced along each edge portion of the liner sheet when the leg sheet is tight; folding the liner sheet, leg sheet, and leg assemblies to form a folded liner sheet; transporting the folded liner sheet to a desired location, and unfolding the liner sheet to a working position on the surface; moving the tanker vehicle onto the liner sheet between the side and end edge portions thereof; moving the leg assemblies to the operating position where bottom ends of the legs rest on the surface separated by the base distance, and the legs slope upward toward each other to form a triangle, and wherein the corresponding edge portion of the liner sheet is attached to the leg assemblies in proximity to a top of the triangle, such that the edge portions of the liner sheet are in a raised position sloping upward from the surface at an angle less than about 75 degrees and form a containment area inside the sloping edge portions of the liner sheet.
The leg assemblies of the disclosed containment system have only two legs, both of which are sloped in the operating position to provide stability and support for the edge portions of the liner sheet in the raised position. The system is economical to manufacture, and convenient to deploy, fold for transport, and transport.
While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where:
A plurality of side leg assemblies 9A are attached to the side edge portions 5 of the liner sheet 3, and a plurality of end leg assemblies 9B are attached to the end edge portions 7. Each leg assembly consists of two legs 11 connected by a fabric hinge 13 as schematically illustrated in
The legs 11 are movable from a collapsed transport position, where the support leg 11B is shown in phantom lines in
The bottom ends of the leg assemblies 9 on each edge portion 5, 7 of the liner sheet 3 are connected to a flexible leg sheet 17 configured such that when the bottom ends of the legs 11 are separated by the base distance BD, the leg sheet 17 is tight between the bottom ends of the legs 11, and such that the leg assemblies 9 are substantially evenly spaced along each edge portion 5, 7 of the liner sheet 3 when the leg sheet 17 is pulled tight. Moving all the side and end leg assemblies 9 to the operating position supports the edge portions 5, 7 of the liner sheet 3 in a raised position sloping upward from the surface 15 at an angle N less than about 75 degrees, such that a containment area is formed inside the sloping edge portions 5, 7 of the liner sheet 3. In the illustrated system 1 the edge portions 5, 7 of the liner sheet 3 slope upward from the surface 15 at an angle N of about 70 degrees.
Thus the presently disclosed containment system 1 uses a leg assembly 9 that has only two legs 11, instead of three as is known in the art. The sheet legs 11A slope at an angle downward from vertical, in contrast to the prior art systems where the walls of the containment area are substantially vertical. The weight of the edge portions 5, 7 of the liner sheet 3 rests on the sloping sheet legs 11A, which in turn are supported by the opposite sloping support legs 11B. The connection of the bottom of the legs 11 by the tight leg sheet 17 prevents the bottom of the support leg from sliding away, and the structure is stable when empty, and when filled with liquid, the weight of the liquid is likewise supported on the sloping sheet legs 11A.
In the illustrated system 1, the sheet legs 11A and support legs 11B are enclosed in fabric leg pockets 19, as seen in
Although it is contemplated that the edge portions 5, 7 of the liner sheet 3 could be fastened to the leg assemblies 9 only at the top of the sheet leg, as schematically illustrated by the connection point 21 in
With the sheet leg pockets 19A fastened along their length to the edge portions 5, 7, and the leg pockets 19 fastened to the leg sheet 17, and the leg sheet 17 fastened to the liner sheet 3, and given the flexible nature of the liner and leg sheets 3, 17, all the parts of the system 1 are connected in their proper orientation when the sheets 3, 17 are pulled tight.
The system 1 can thus be folded by moving the legs 11A, 11B of each leg assembly 9 to the collapsed transport position of
For example a flexible suspension tape 23 is schematically illustrated in
For transport on a vehicle mounted roller, the liner sheet 3 can be folded for transport to a folded position shown in
The side edge portions 5A and 5B and attached side leg assemblies 9A are folded to the center of the liner sheet 3 through the steps schematically illustrated in
The illustrated roller 33 comprises a plurality of right and left spokes 39 extending radially from the rotational axis RA of the roller 33, and a cross bar 41 connecting a mid-point of each right spoke 39 with a mid-point of a corresponding left spoke 39, such that the folded liner sheet 3F lies on the cross bars 39 as seen in
The present disclosure provides a method of providing a temporary containment system for a tanker vehicle 29 on a surface 15 at a work site. The method comprises providing a flexible liner sheet 3 with first and second side edge portions 5A, 5B and first and second end edge portions 7A, 7B; attaching a plurality of side leg assemblies 9A to the side edge portions 5A, 5B of the liner sheet, and attaching a plurality of end leg assemblies 9B to the end edge portions 7A, 7B of the liner sheet, wherein the bottom ends of the leg assemblies 9 on each edge portion 5, 7 of the liner sheet 3 are connected to a flexible leg sheet 17; folding the liner sheet 9, leg sheet 17, and leg assemblies 9 to form a folded liner sheet 3F; transporting the folded liner sheet 3F to a desired location, and unfolding the liner sheet to a working position on the surface; moving the tanker vehicle 29 onto the liner sheet 3 between the side and end edge portions 5, 7 thereof; and then moving the leg assemblies 9 to the operating position, conveniently by pulling the leg sheet 17 away from the liner sheet 3, such that the edge portions 5, 7 of the liner sheet 3 are in the raised position sloping upward from the surface at an angle less than about 75 degrees and form a containment area inside the sloping edge portions 5, 7 of the liner sheet 3, with the tanker vehicle inside the containment area of the containment system 1 as seen in
The disclosed containment system is economical to manufacture, requiring only two legs for each leg assembly. The simplified system 1 is also convenient to install, fold, and transport.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all such suitable changes or modifications in structure or operation which may be resorted to are intended to fall within the scope of the claimed invention.