The invention lies in the field of secure weather containment systems for chemical tanks of approximately 25 to 500 gallon capacity, and is especially applicable for unmanned sites.
In current practice 25 to 500 gallon chemical tanks with a pump are frequently staged at industrial sites and utilized to pump chemicals upon need. Frequently the sites are unmanned. As indicated in the “prior art” of
The pan is provided so that any spill, as well as run-off rain that picks up chemicals leaking from orifices of the tank or pump, will be collected in the pan. Rain water is of particular concern in these circumstances as the rain that washes over the tank frequently becomes contaminated with leaking chemical. E.g. fittings installed not only on the tank but also around the pump and power lines and supply lines and gauge lines can leak at their seals.
Environmental issues are arising with these chemical tanks handled in accordance with the current practices. The issue is made more pressing when the tanks are located near urban areas and particularly when the tanks are unmanned. As mentioned above, a containment tank has fittings, such as for a chemical supply line and a sensor line, and chemicals can leak at these fittings over time. The pump can also leak chemicals at its seals. Rain washes the chemicals down into the pan, and although the potentially chemically laden rainwater that collects in the pan is in theory to be disposed of using proper procedures, unfortunately a drain in the pan may sometimes simply be pulled and the collected rainwater, contaminated or not, drained into the ground. Further, birds, animals and livestock may drink the contaminated water collected in the pan and become ill.
In particular in the oil and gas industry, and especially in regard to unmanned chemical tanks located near urban areas by such industry, the EPA is requiring tighter controls over the chemical tanks. Thus, it is desirable to improve the containment system for primary chemical tanks, in particular for tanks utilized for supporting pumping applications on pipelines, well heads, refineries and pulp and paper facilities. Most of these locations dictate unmanned operations, where an improved secondary containment system would be valuable to properly prevent all chemical spills and contamination.
One system developed in response to the animal problem mentioned above is illustrated in
U.S. Pat. No. 6,149,026 to Manson teaches a secondary containment tank for enclosing a primary tank, and the inventor offers a remark about a possible provision for enclosing a pump. However, the containment system of Manson makes no provision for the treatment of power and chemical lines in and out of the system, especially as required by a pump, and the structure of the Manson system is unnecessarily expensive vis-à-vis the instant invention. The structure of the secondary and primary vessels of Manson are independent. Each Manson vessel provides self-sufficient, independent support. And the primary vessel has no portion exposed, for maintenance and convenience.
By contrast, the mating and nesting structure of the instant invention provides economies of construction cost and space while containing all leaks and spills from the primary container and the pump. (As “nesting” is used herein, two structures that “nest” when mated together exhibit enhanced structural strength, in excess of either structure alone.) The instant invention is comprised of at least one primary tank (preferably constructed essentially of one piece of plastic and designed to hold fluids such as petroleum products, chemicals or water solvents,) which primary tank sealingly mates with and nests within a secondary containment tank, preferably also constructed essentially of one piece of plastic, with a primary tank portion exposed. The nested construction permits economies of structure, space and cost, not possible with free-standing primary and secondary tanks. Provision is made for containing a pump, including utilizing a gravity feed.
A portion of the primary tank is exposed, preferably a primary tank lid portion. The secondary tank of the instant invention is preferably constructed to provide, in conjunction with portions of one or more primary tanks themselves, at least 110% chemical containment in the case of a primary tank rupture, as well as a containment housing for at least one pump. Fittings for lines are provided in and out of the secondary container above its 10% fluid containment level, to avoid issues of chemical leak at the secondary tank fittings and seals and thus the possible contamination of rainwater thereby.
The primary tank receives structural support and economy of space by significantly nesting within the secondary tank. In a preferred embodiment the secondary tank sealingly secures to and under a top portion of at least one primary tank. This construction permits the top or tops of the primary tank(s) to be accessible. The secondary tank is further designed to house the pumping mechanism(s), thus eliminating the risk of the contamination of rainwater by pump fittings, and preferably provides an access lid, sealingly mated to primary tank and/or the secondary tank portion.
The system of the instant invention significantly encloses at least one primary tank and pumping mechanism within a nested secondary container, protecting the surrounding environment from contamination by rainwater washing over chemicals leaking from fittings associated with either the primary tank or the associated pump as well as from spillage from a primary tank rupture. Preferably a portion of the primary tank(s) are exposed. A preferably unitary secondary tank component, together with primary tank portions, provides at least 110% containment for the primary tank fluids. Secondary tank fittings or openings are located above the 110% containment level of the primary tank liquid. In preferred embodiments rain water is inhibited from entering the secondary containment area by weather tight sealing between the secondary and primary tank(s) and the access lid.
The containment system of the instant invention is particularly useful to hold liquid for pumping applications in pipelines, well heads, refineries and pump and paper facilities. These locations are largely unmanned, and secondary containment is important to prevent chemical contamination of the environment, especially when the facilities closely interface with urban environments. Economies of material and cost and space arise with the nesting structure construction.
The invention includes a system and method for environmental containment for the chemical content of approximately 25 to 500 gallon chemical tanks and associated pumps. The system includes at least one primary tank substantially nested within a secondary tank, the secondary tank and primary tank sealingly mating against penetration by weather, with a portion of the primary tank exposed, preferably a lid portion. The secondary tank is sized to accommodate at least one pump and structured and sized in conjunction with the primary tank(s) to contain at least 110% of the primary tank(s) capacity.
A better understanding of the present invention can be obtained when the following detailed description of the preferred embodiments are considered in conjunction with the following drawings, in which:
The drawings are primarily illustrative. It would be understood that structure may have been simplified and details omitted in order to convey certain aspects of the invention. Scale may be sacrificed to clarity.
Features of containment system 001 include an EPA friendly closed container 002 having an externally visible float level indicator and externally accessible cap. The secondary container 003 has built-in structural ribs and lift handles 017 for convenience. Edges of the secondary container are structured for weather tight seals. Grommetted access holes (
The nipple 009 illustrated in
The lid portions 010 of primary containers 002 could be domed shaped for enhanced water and snow runoff. Access lid 024 on the double-sized secondary container 023 should seal with primary container lid portions 010 in an analogous manner as in the single primary tank secondary container. The weather type rain guard on secondary container 023 should be analogous to the weather type rain guard on secondary container 003. In the double secondary container 023, spaces are provided to position a single pump to run both primary tanks or to position two pumps each to run one primary tank or both pumps to pump chemicals from both tanks.
In operation primary tank 002 is placed within secondary container 003. Primary tank lid 010 sealingly mates with upper edges of secondary container 003. Primary tank 002 contains within it float gage 008. A vented cap 005 sealingly mates with an opening in lid 010. Weatherproof lid 004 is latched by means of latches 006 to sealingly mate against portions of secondary container 003 and primary container 002. Pump motor P/M has been placed inside secondary container 003. Lines connect pump motor PM with a nipple at the bottom of primary container 002. Grommet access holes 014 provide access for data, power, fluid lines and the like through secondary container 003 above the 110% containment line. With such means the pump can be operated in accordance with power and control signals and status of the pump in the tanks can be monitored through information lines. The level of fluid in the primary tank can also be visually monitored from the exterior through the float gauge 008 with the portion 012 extending through the top lid 010 of primary container 002.
The foregoing description of preferred embodiments of the invention is presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise form or embodiment disclosed. The description was selected to best explain the principles of the invention and their practical application to enable others skilled in the art to best utilize the invention in various embodiments. Various modifications as are best suited to the particular use are contemplated. It is intended that the scope of the invention is not to be limited by the specification, but to be defined by the claims set forth below. Since the foregoing disclosure and description of the invention are illustrative and explanatory thereof, various changes in the size, shape, and materials, as well as in the details of the illustrated device may be made without departing from the spirit of the invention. The invention is claimed using terminology that depends upon a historic presumption that recitation of a single element covers one or more, and recitation of two elements covers two or more, and the like. Also, the drawings and illustration herein have not necessarily been produced to scale.
This application is related to, and claims priority to, Provisional Application Ser. No. 61/070,802 filed Mar. 26, 2008 entitled Secure Weather Containment System—Enviro Tank, inventor Kirk D. Claborn.
Number | Date | Country | |
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61070802 | Mar 2008 | US |