Patent Application
20170298587
The present invention relates to inflatable structures, and more particularly to an inflatable containment structure, and a method using such inflatable containment structure for recovering hydrocarbons or toxic fluids, or mixtures of both, from a compromised sub-sea structure.
Above-ground inflatable structures/enclosures for sheltering humans and or the contents of such structure and which utilize inflatable supporting beams supporting a flexible skin or sheeting, are generally known.
Commonly-assigned U.S. Pat. No. 9,267,765 teaches one such structure/enclosure which has inflatable supporting beams, which are inflated with air. The structure/enclosure, due to the resilitent flexibility of the inflatable beams, produces a structure/enclosure that is specially adapted for an environment such as a war zone, where the structure/enclosure need be resiliently flexible and not totally rigid to thereby better withstand blast waves emanating from ordinance exploding nearby. Vertical flexible tethermasts assist in securing and tethering the inflatable beams. Such tethermasts may be secured together by horizontal support members. An external fly may further be provided.
U.S. Pat. No. 5,570,544 teaches an air-inflatable frame(s) which provide a structure for supporting an external sheeting, to thereby provide inter alia a supported tent structure. The inflatable frames are provided with restraint members which prevent full extension of the inflatable air beams upon inflation thereof, and serve to cause the inflatable frame to assume a desired predefined polygonal shape of the tent.
EP 0494053 teaches an above-ground semi-cylindrical shed or hanger, such as for sheltering an aircraft during maintenance thereon, such hanger having a plurality of supporting arches consisting of inflatable tubular members. Wind bracing elements, in the form of guy wires 15, 17, are disposed on the outside of the arches. A covering sheet is disposed above the supporting structure formed by the plurality of parallel juxtaposed supporting arches.
U.S. Pat. No. 2,837,101 teaches, in one embodiment thereof (
U.S. Pat. No. 6,019,112 to a Home Greenhouse Kit teaches a greenhouse having a semi-circular housing formed by two layers of flexible sheeting and a plurality of elongated parallel rib channels having inflatable tubes therein which are situated between the two layers. A floor portion forms a base and is connected to the housing portion.
U.S. Pat. No. 5,964,767 to a Chemical, Biological Explosive Containment System teaches a plurality of inflatable air beams having a truncated hexagonal pyramid shape, which may be placed over a bomb, IED, or other explosive device which need be detonated so as to neutralize it. A bomb containment blanket 20 is arranged parabolically within the air beam suspension support structure in a tent-like fashion. The containment blanket 20 is attached to the inflatable support structure with a rope or cord. The bomb containment blanket 20 further possess an access portal 21 to allow hazard mitigation foams to be delivered inside the explosion containment/hazard mitigation region 12 within the bomb containment blanket.
Commonly-assigned U.S. Pat. No. 8,991,104 to a “Method and Apparatus for Distributing a Load about an Air Beam” teaches an air beam supported structure/enclosure, further teaching an air beam sling or hug strap for distributing loads to/from the individual air beams.
Also teaching ways and means for distributing loads to and from air beams, U.S. Pat. No. 7,176,876 teaches an alternative means of coupling to an air beam, using permanently-affixed laceloops, to allow application/distribution of loads thereto.
In addition, it is known to construct, on a seabed floor, a subsea structure of rigid materials surrounding a compromised structure such as a leaking oilwell or pipeline, to collect oil leaking from such structure and by means of tubing pump such collected oil to surface.
The above background information is provided for the purpose of making known information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information, or the reference in the drawings to “prior art” constitutes prior art citable against the present invention.
Disadvantageously, however, as regards the aforementioned undersea structures of rigid materials and construction, due to their rigid and non-deformable nature such are frequently destroyed and/or their containment capacity seriously compromised when they are exposed to transitory but severe undersea pressure waves caused by, typically, undersea earthquakes.
As regards the aforementioned inflatable air beam structures, none of the above art teaches, alone or in combination, in the manner more fully particularized herein, a resiliently deformable structure having a central hub at an apex or crown of such structure and a plurality of elongate inflatable beam members extending radially outwardly and downwardly therefrom, which beam members overly or underly a textile sheet member to thereby support such sheet member in the form an enclosure. Specifically, none of the aforementioned prior art teach or suggest a structure is particularly suitable for use undersea in collecting and recovering leaking fluids from a compromised undersea vessel or structure and further capable of withstanding transitory but nonetheless large pressure forces which may occur in areas of the ocean where, for example, there are large undersea currents and/or large pressure waves generated for example by undersea earthquakes.
Nor do any of such prior art structures suggest the affixing of a riser to a central hub mounted on the crown or apex of the resiliently flexible structure, to allow withdrawing of fluid collected from within such enclosure to be pumped to surface and thus recovered.
Nor for that matter does the prior art suggest or teach a method of being able to deploy a structure subsea which is capable of collecting and recovering leaking fluids to surface, yet still being able to withstand large transitory pressure waves which may be present.
In order to provide a containment structure particularly suited for the uses set out herein, and more particularly inter alia for undersea use in collecting and recovering fluids undersea which are leaking from a compromised sunken oil transport vessel or structure such as leaking oil well or pipeline in harsh environmental conditions, in a first broad embodiment the invention is directed to a containment structure which is not only easily portable and deployable but more importantly is resiliently deformable to withstand large localized disturbances, such as undersea earthquakes, tidal and thermal convection, and the tsunami-type waves and forces generated by such undersea disturbances.
Specifically, not only does the present containment structure to be easily and relatively quickly transported in an uninflated condition and thereafter positioned and inflated about a compromised vessel on a seabed floor, but such containment structure is further capable of being resiliently deformed when exposed to transient pressure forces yet nonetheless retain structural integrity and return to its original and desired shape to thereby serve its intended function.
The ability of the containment structure of the present invention to partially deform is particularly advantageous for a containment structure, as such may not infrequently, particularly in a sub-sea environment, be exposed to transitory pressure waves/forces exerted on one or more sides of such structure. The ability to resiliently deform and thereafter return to its original shape and position above a compromised structure sitting on a seabed floor and allowing the continued collection and pumping to surface of collected leaking fluids is particularly desirous and important feature of the present invention.
Accordingly, in order to realize one or more of the above advantages, the containment structure of the present invention in a broad embodiment comprises:
The shape of the containment structure, namely having a raised central portion at the central hub, such as, for example, a hemisphere, cone, or polyhedron shape and having the center portion at the crown or apex thereof and having an open bottom end, is particularly useful in that such containment structure via its open (underside) base, allows ingress of the leaking fluids (typically escaping from a compromised subsea structure lying on the ocean floor) into the enclosure thereof via the bottom end, and removal of collected fluids via the fluid exit port at the crown or apex.
Advantageously, such shape of the containment structure utilizes a physical property of the leaking fluid(s) from compromised undersea structures (which is typically oil and other hydrocarbons in liquid or gaseous form which are escaping from a ruptured or leaking vessel or undersea structure such as an oilwell or pipeline), namely that such leaking hydrocarbons are typically substantially lighter (i.e. of less density) than the surrounding sea water. Thus in such cases the containment structure shape advantageously further allows the leaking fluids collected therewithin [such fluids, such as oil and gases which all have a lower density than water] to rise to the top (crown or apex) of the enclosure, simultaneously displacing any water and allowing the hydrcarbons to thereafter be removed from the crown/apex of the enclosure substantially free of water, via a riser coupled to a fluid exit port situated in the central hub, and thereafter be pumped to surface.
Specifically, the containment configuration advantageously serves to forcibly separate, due to the force exerted by collected hydrocarbons rising therein, water from fluids flowing into the enclosure by displacing any water within the dome downwardly and away from the riser and toward the bottom open base of the enclosure dome. The (lighter) rising hydrocarbons can then be collected from the crown/apex of the structure without entrained water, thus reducing [and to a substantial extent eliminating, depending on the rate of flow of the first fluid into the hemispherical dome and the rate at which such first fluid is pumped from the dome] undesired seawater being recovered to surface.
The inflatable beam members are typically inflated by a second fluid, typically water, but such second fluid may be air, nitrogen, carbon dioxide, or a mixture of any or all of the foregoing with water, which is pumped or injected into an interior of the inflatable beam members. The second fluid may, but preferably is not, the same as the first fluid, and as indicated above, is preferably water.
Due to the inflatable beam members being constructed of a fixed interior volume, inflation with the second fluid causes the beam members to assume their desired intended shape. Distortion of such beam members from such desired initial shape and fixed interior volume is thereby resisted, due to the maximum volume of the beam member being in its intended, undeflected state/configuration.
Typically, the fluid by which the inflatable beams are inflated, particularly when the resulting containment structure used in subsea applications, is ocean water. Since water, including ocean water, is incompressible, inflation of the beam members may be further accompanied by injection of a gas such as air, carbon dioxide, or nitrogen so as to further pressurize the inflatable beam members. Such injected gas may be entrained with the water when the beam members are being inflated, or may be injected separately before or after inflation with water.
Individual beam members may, in one embodiment of the invention, be provided with a fluid receptacle for injection of the second fluid. Such fluid receptacle is in fluid communication with an interior of a corresponding beam member, and has a fluid coupling to allow temporary communication with a supply hose containing the second fluid. The receptacle may further possesses a one-way valve to allow a supply of pumped fluids to be provided, yet once injected, to be retained within each inflatable beam member. The second fluids being injected may be provided via a mating fluid coupling at a distal end of a fluid supply hose. An undersea vehicle may manipulate a fluid supply hose and couple same to each receptacle on each beam member to successively inflate such beam members when the hemispherical dome structure of the present invention is submersed undersea. Alternatively, the beam members may be inflated at surface, and the resulting hemispherical structure/enclosure thereafter lowered in place over the compromised subsea structure.
Alternatively, however, in a preferred embodiment of the above containment structure of the present invention the central hub further has port means located on the cylindrical outer periphery thereof which is configured to act as a manifold to provide and distribute the second fluid to an interior of at least one, and preferably each, of the inflatable beam members, for inflating such beam members. In a further refinement of such alternative preferred embodiment the port means comprises a plurality of ports corresponding in number to the plurality of inflatable beam members, arranged in spaced relation around the cylindrical outer periphery of the central hub. Each of the plurality of ports are configured to provide a second fluid such as water, air, nitrogen, carbon dioxide, or a mixture thereof to an interior of a corresponding of the plurality of inflatable beam members.
In a further preferred embodiment the port means is coupled to a supply of said fluid and configured to provide said fluid to an interior of said inflatable beam members to thereby inflate said inflatable beam members.
In a further preferred embodiment, the port means comprises a plurality of ports spaced about said cylindrical outer periphery of said central hub, said plurality of ports corresponding in number to said plurality of inflatable beam members and each of said ports coupled to and in fluid communication respectively with a first longitudinal end of corresponding of said plurality of inflatable beam members, said central hub configured to inflate said beam members via said ports when said ports are supplied with said fluid.
Preferrably, in each of the aforesaid embodiments, the central hub is coupled to an elongate fluid supply hose, and the central hub, when supplied with said fluid via said fluid supply hose, is adapted to provide said fluid to an interior of each of said inflatable beam members via said central hub so as to inflate said inflatable beam members. Equally preferably, the central hub may possess a pressure regulator, and the elongate supply hose is an air supply hose. In such embodiment the central hub, when supplied with said air via said air supply hose, is configured to provide air to an interior of each of said inflatable beam members so as to pressurize said inflatable beam members at a uniform pressure.
Inflation of the inflatable beam members, preferably via the ports on the central hub as described above, causes such beam members to become semi-rigid and capable of supporting the textile or fabric containment sheet in the desired shape particularly suited for collecting and trapping low-density leaking fluid centrally within the textile containment sheet.
In a further refinement, the central hub is provided with a plurality one-way valves, each of said plurality of one-way valves allowing flow of said second fluid from within said central hub to a respective of said inflatable beam members, but preventing reverse flow of said second fluid from said inflatable beam members into said central hub.
In a preferred embodiment, the one or more anchor members comprise one or more cast concrete members. In an alternative embodiment, the one or more anchor members may comprise a single, integral, circular member, coupled to the lower portion of the textile fabric sheet and/or the distal ends of each of the inflatable beam members, to thereby ensure the so-formed structure remains tethered immediately above the compromised subsea structure which is leaking fluids.
In a further preferred embodiment, each of the inflatable beam members of the structure are elongate and cylindrical, and are each coupled to the textile containment sheet via points of coupling on a plurality of circumferential strap members disposed along said longitudinal length of each of said inflatable beam members.
In a refinement thereof, the inflatable beam members each have disposed around a portion of a periphery thereof and in spaced-apart relation along said longitudinal length of each, a plurality of circumferential strap members, each inflatable beam member being coupled to said textile containment sheete via a point of coupling on each of said plurality of circumferential strap members thereon.
Other means of coupling the inflatable beam members to the flexible textile or fabric sheet member will now occur to persons of skill in the art, and are accordingly contemplated within the scope of the present invention.
As mentioned above, in a highly-preferred embodiment of the above containment enclosures/structure such further comprises a flexible, hollow, tubular fluid transport riser in fluid communication with an interior of the hemispherical enclosure, configured and of a length sufficient to extend to surface when said containment structure is submerged sub-sea. Such riser allows transport of the collected leaking fluids from the interior of said enclosure to a vessel situated on the ocean surface.
The tubular fluid transport riser is coupled to the central hub and extends upwardly from the central hub. The central hub has an aperture/fluid exit port therein permitting flow of fluid from within said so-formed enclosure through the central hub member and into said riser.
In another broad aspect of the present invention, such invention comprises a method for containing and recovering a first fluid which is leaking or flowing from a compromised sub-sea structure. Such method comprises the steps of:
In a preferred embodiment, such method further comprises the step of attaching one or more anchor members which rest on the ocean floor to said second mutually opposite ends of each inflatable beam member, so as to firmly tether the containment structure above the compromised structure.
The step of attaching said one or more anchor members to said second mutually opposite ends of each of said plurality of inflatable beam members may be conducted at surface and prior to lowering said textile containment sheet, said inflatable beam members, and said central hub member within said body of water to overly at least portions of said compromised sub-sea structure.
Alternatively, the step of attaching the anchor means to the second mutually opposite ends of each inflatable beam member is conducted sub sea, after having lowered the textile containment sheet, the inflatable beam members, and the central hub member within said body of water to at least partially overly the compromised sub-sea structure.
Similarly, the inflatable beam members may be inflated with a fluid at surface and prior lowering said textile containment sheet, said inflatable beam members, and said central hub member within said body of water to overly at least a portion of said compromised sub-sea structure.
Alternatively, the inflatable beam members may be inflated subsea after having lowered said textile containment sheet, said inflatable beam members, and central hub member within said body of water so as to at least partially overly said compromised sub-sea structure, and after having attached said anchor means to said second longitudinal ends of said inflatable beam members.
In one embodiment of the present method, the inflatable beam members are inflated with air, water, or a mixture thereof by a submersible undersea vessel, said undersea vessel configured to supply said air, water, or a mixture thereof to a receptacle on one or more of said inflatable beam members, and supplying said air, water, or mixture thereof to said receptacle to thereby inflate said inflatable beam members.
Alternatively, the individual inflatable beam members may be inflated via coupling a fluid supply hose to the central hub member and using the central hub as a manifold and distributing the second fluid supplied via said fluid supply hose to each of the individual beam members.
The above summary of the structure and method of the present invention does not necessarily describe the entire scope of the present invention. Other aspects, features and advantages of the invention will be apparent to those of ordinary skill in the art upon a proper review of the entire description of the invention as a whole, including the drawings and consideration of the specific embodiments of the invention described in the detailed description.
The following figures depict selected embodiments of the apparatus and method of the present invention. For a full definition of invention, reference is to be had to the specification as a whole, including the Summary of the Invention, the Detailed Description of Some Embodiments, and the claims.
The following Figures are appended, in which:
The containment structure 10 shown in each of
In each of the embodiments shown in
A plurality of elongate, inflatable beam members 25 are provided—first longitudinal ends 26 thereof being arranged circumferentially around outer periphery 20 of hub member 18 and (when inflated) extend radially outwardly and (when tethered to one or more anchor members 32) extend in a downwardly-curved manner from central hub 18.
Inflatable beam members 25 may overlie textile containment sheet 22 as best shown in
Textile containment sheeting 22 is affixed to beam members 25 at discrete points (not shown) or continuously along a longitudinal length 27 of each inflatable beam member 25 (ref.
In the embodiment shown in
Likewise, with regard to the embodiment shown in
Textile containment sheet 22 is preferably impervious or substantially impervious to the (first) fluid being collected therewithin, which as mentioned above, is typically oil and gaseous hydrocarbons. As such hydrocarbons may further contain toxic and acidic gases such as hydrogen sulfide, it is further preferable that such textile containment sheeting be impregnated with waxes or other protective compounds to insulate the fibres thereof from such acidic gases and thereby better resist decomposition thereof. By having the above configuration and manner of construction, beam members 25 when inflated and tethered (in the manner hereinafter explained) are thus able to support textile containment sheet 22 in a downwardly-curved hemispherical dome enclosure shape, having an open bottom side 40.
One or more anchor members 32 are further provided, to allow textile containment sheet 22 and/or beam members to be tethered thereto, via rope, chain, or cables 28, to retain the textile containment sheet 22 and beam members proximate to and in a desired position around and directly above the point of compromise of sub-sea structure 16. Such one or more anchor members 32 may comprise a single unitary structure 32′ of substantial mass, typically but not necessarily of cylindrical in shape, which is adapted to rest on the ground or a sea-bed floor 99, as shown in
Alternatively, one or more anchor members 32 may comprise a plurality of anchor members 32″. In such embodiment one or both of textile containment sheeting 22 and/or one or more beam members 25 may be tethered via tether means 28 such as a rope, chain, or cable member to such anchor members 32″ as shown in
A fluid exit port 130 may be located at the crown or apex of the containment structure 10 and typically located in the central hub 18, for allowing first fluids 12 flowing into the containment structure to rise and displace water downwardly, and thereafter be removed via pumping from such containment structure 10 to surface.
Beam members 25, when inflated with a second fluid 50, typically comprising water or air, and preferably a combination of both. Other gases other than air may be employed, such as carbon dioxide or nitrogen, for the purposes of pressurizing beam members 25 where added resiliency of such beam members is desired. Where containment structure is deployed at greater depths, greater gaseous inflation pressures are needed to withstand greater hydrostatic forces imposed on such beams with increased depths. Advantageously, to a limited extent the increased inflation pressures, particularly if such inflation of beam members is conducted at depth and not at surface, does not necessarily translate into inceased ball thickness of the inflatable beam members, as the increased inflation pressure will be offset by increased hydrostatic forces at depth. When second longitudinal ends 30 of beam members 25 thereof are tethered to anchor members 32, beam members 25 support textile containment sheet 22 in a downwardly-extending shape extending downwardly from said raised central hub 18, to form an enclosure 10 having an open bottom end 40 above compromised undersea structure 16.
In one embodiment, the containment structure 10 comprises a hemispherical dome, as best shown in
To allow inflation of beam members 25, in one embodiment each of said beam members are provided with a separate receptacle 70 for injection of the second fluid 50. Each of receptacles 70 are in fluid communication respectively with an interior of a corresponding of the inflatable beam members 75 and further having a fluid coupling means (not shown), typically a threaded fluid coupling as well known to persons of skill in the art, thereon to allow a supply hose (not shown) to be coupled to receptacle 70 and thereby permit the second fluid 50 to be pumped into each of said inflatable beam members 25. In such embodiment each receptacle 70 thereon further possessing a one-way valve 90 to allow said second fluid, once injected in a respective of said plurality of inflatable beam members 25, to be retained therein and prevented from escaping. Beam members 25 may be inflated at surface by supply of second fluid 50 to each of receptacles 70, or by an undersea submersible vessel individually and successively coupling a supply of said second fluid 50 to each receptacle 70.
More preferably, however, central hub 18 is provided with port means 101 thereon, In this regard, reference is to be had to
To increase structural integrity and avoid loss of second fluids 50 from each beam member 25 in the event one of the individual beam members should spring a leak or be structurally compromised, in a preferred embodiment central hub 18 is provided with a plurality of one-way valves 90, preferably at the location of each of ports 102, as shown schematically in
To facilitate removal of collected first fluids 12 from an interior of containment structure 10, a flexible, hollow, tubular fluid transport riser 120 is typically coupled to exterior surface of central hub 18, so as to receive and allow pumped removal of first fluids 12 via fluid exit port 130 in central hub 18. Central hub 18 is in fluid communication with an interior of containment enclosure 10 via fluid exit port 130. Riser 120 is preferably a flexible hose, and of a length sufficient to extend to surface to surface vessel 17, and allows pumping of first fluid 12 from an interior of said enclosure 10 to said surface.
In a preferred embodiment, inflatable beam members 25 are couple to textile containment sheet 22 by having disposed around a portion of a circumference thereof and in spaced-apart relation along a longitudinal length 27 of each a plurality of circumferential strap members 80. Each inflatable beam member 25 is coupled to textile containment sheet via a point of coupling on each of said plurality of circumferential strap members thereon.
Method for Containing and Recovering Fluids Leaking from a Compromised Subsea Structure
The various manners of operation and methods for containing and recovering fluids leaking from a compromised subsea structure will now be described.
In one embodiment such method comprises the steps of:
In a further embodiment, the step of attaching the one or more anchor members 32 to said second mutually opposite longitudinal ends 30 of each of inflatable beam members 25 is conducted at surface and prior to lowering textile containment sheet 22, inflatable beam members 25, and central hub member 18 within said body of water to overly at least portions of said compromised sub-sea structure 16.
In an alternative further embodiment, the step of attaching the one or more anchor members 32 to the second mutually opposite longitudinal ends 30 of each of inflatable beam members 25 is conducted at depth, and after lowering textile containment sheet 22, inflatable beam members 25, and central hub member 18 within said body of water to overly at least portions of said compromised sub-sea structure 16.
In a further alternative method, inflatable beam members 25 are inflated with second fluid 50 at surface and prior lowering textile containment sheet 22, inflatable beam members 25, and central hub member 18 within the body of water.
In a further alternative method, inflatable beam members 25 are inflated subsea after having lowered textile containment sheet 22, inflatable beam members 25, and central hub member 18 within the body of water so as to at least partially overly said compromised sub-sea structure 16, and after having attached anchor means 32 to the second longitudinal ends of inflatable beam members 25. Such embodiment is particularly advantageous when employed with a central hub 18 having ports 102 thereon coupled to and in fluid communication with first longitudinal ends and having fluid inlet spigot 71 thereon coupled to a fluid supply hose supplying second fluid 50. In such manner beam members 25 may be inflated and containment structure 10 erected upon fluid supply hose supplying second fluids 50 from surface.
In the embodiment where instead the central hub member 18 is not provided with ports and instead each of beam members 25 are provided with a receptacle 25 for receiving second fluids 50, the method may comprise utilizing an undersea submersible vessel (not shown) which is configured to allow supply of second fluid 50 to the receptacles 70.
Use of examples in the specification, including examples of terms, is for illustrative purposes only and is not intended to limit the scope and meaning of the embodiments of the invention set out and described in the disclosure. Numeric ranges are inclusive of the numbers defining the range. In the specification, the word “comprising” is used as an open-ended term, substantially equivalent to the phrase “including, but not limited to,” and the word “comprises” has a corresponding meaning.
The scope of the claims should not be limited by the preferred embodiments set forth in the foregoing examples, but should be given the broadest interpretation consistent with the description as a whole, and the claims are not to be limited to the preferred or exemplified embodiments of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2927192 | Apr 2016 | CA | national |
