Subsea oil collector
A subsea fluid collector is provided, comprising a container having a fluid inlet and a fluid outlet, and a vessel positioning device which is attachable to a submerged vessel leaking oil or other fluids. The container is positioned by the vessel positioning device to receive, through the fluid inlet, a leaking fluid (such as crude oil, gasoline, diesel, or the like) exiting from a fluid leak source on the vessel, and the water residing within the container is displaced as leaking fluid enters the container. The vessel positioning device may be attached or detached from the vessel by divers or remotely using a remotely operated vehicle (ROV). In one embodiment, the container may be guided into position above the leak by a guide cable. Once the container is filled by the leaking fluid, it ascends to the surface of the sea for retrieval and removal of the contents.
This nonprovisional application is based on prior provisional applications, U.S. Ser. No. 60/436,119 filed on Dec. 23, 2002, and U.S. Ser. No. 60/444,028 filed on Jan. 31, 2003.
BACKGROUND OF THE INVENTIONI. Field of the Invention
The present invention relates generally to devices and methods used to contain leaks of oil and other liquids having a specific gravity less than that of water from vessels or other fluid-containing structures below the surface of the ocean or any other body of water.
II. Background and Prior Art
It is well known that oil tankers, barges, and other oil-containing vessels occasionally sustain damage and release the contents of their cargo into the surrounding water. The cargo is typically oil, although other combustible fuels having a specific gravity less than water, such as gasoline, diesel, and kerosene, are often transported in this manner. Because the most common cargo is oil, however, that term will be used exclusively herein with the understanding that it is representative of all fluids having specific gravities less than 1.0. Such leaks sometimes occur when the vessel is still afloat, and in other cases, the vessel sinks to the bottom of the ocean and remains their permanently. In those instances when a vessel sinks, the oil may still be contained within the vessel, but may slowly leak out through the damaged hull or other opening. By virtue of its lower density, the oil will rise to the surface of the water. This accumulation of oil, sometimes referred to as an “oil slick”, is particularly difficult to collect, prompting tremendous efforts over the last several decades to devise equipment and methods to remove the oil from the surface.
Consequently, there is a great need for a system which can be employed to retrieve oil leaking from sunken vessels in a manner which prevents the oil from reaching the surface. Even if the oil-containing vessel is not leaking, the gradual effects of corrosion and ocean currents over the course of time will eventually cause the oil to escape from the vessel. Therefore, it is desirable to have an oil collection system which can also be positioned above a release hole formed into the penetrated hull of the vessel to remove the oil.
SUMMARY OF THE INVENTIONTherefore, one object of the present invention is to provide a subsea oil collector which collects oil from below the surface of the water.
It is also an object of the present invention to provide a subsea oil collector which can be positioned on the hull of a vessel at a select location.
A further object of the present invention is to provide a subsea oil collector which can be retrieved onto surface vessels or emptied in accordance with acceptable methods.
Another object of the present invention is to provide a subsea oil collector which can be guided into place by a remotely operated vehicle (ROV).
Accordingly, a subsea fluid collector is provided, comprising a container having a fluid inlet and a fluid outlet; a vessel positioning device operatively connected to the container; a closure mechanism to close the fluid inlet; and a closure mechanism to close the fluid outlet; wherein the container is positioned by the vessel positioning device to receive, through the fluid inlet, a leaking fluid (such as crude oil, gasoline, diesel, or the like) exiting from a fluid leak source on the vessel, and wherein water, if any, residing within the container is displaced as leaking fluid enters the container. Preferably, the vessel positioning device includes means for attaching to and detaching from the vessel, and is optionally controlled remotely. Also, it is preferable that both the inlet aclosure mechanism and outlet closure mechanism are controlled remotely, or by the volume of fluid collected within the container. In a preferred embodiment, the container has negative buoyancy prior to being filled with the leaked fluid.
In an alternate embodiment, the collector further includes a buoy residing at or near the surface of the water; and a guide cable having a first end operatively attached to the buoy, and a second end operatively attached at or near the fluid leak source; and wherein the container is slidably attached to the guide cable for ascent and descent. Optionally, a speed control means for controlling the speed at which the container slides along the cable is also present. In a further arrangement, the collector further inclues a fluid conduit operatively connected between the fluid outlet on the container and the buoy, wherein the conduit permits transfer of fluid from the container to the buoy.
In another alternate embodiment, the collector further includes a ballast chain and handling wire wherein the container is attached to ballast chain which is in turn attached to a lighter, high tensile, handling wire. The chain provides negative buoyancy to assist the container on its descent. Once the container reaches the ocean bottom, and the ballast chain lays on the ocean bottom, the container can be more easily maneuvered by an ROV with the assistance of the handling wire. The handling wire can be retrieved onto a reel type mechanism to assist the collector with a controlled ascent after it has been filled with fluids.
A method for collecting fluids below the sea is also disclosed, comprising the steps of providing a fluid collection container having a positioning mechanism, a fluid inlet, and a fluid outlet; mounting the container using the positioning device to a submerged vessel having a fluid leak source and positioning the fluid inlet above the leak source; permitting the leaking fluid to enter the container until the container is filled with fluid; closing the fluid inlet; and moving the container to the sea surface where it can be retrieved onto a surface vessel or the fluids can be transferred to a surface vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
Unless otherwise noted herein, all construction materials are fluid impervious, and all attachments between such components are structurally sound. Materials and methods are intended to impart a maximum level of strength and structural rigidity, while keeping the invention as lightweight and easy to use as possible. Certain features which are used in assembling or operating the invention, but which are known to those of ordinary skill in the art and not bearing upon points of novelty, such as screws, bolts, nuts, welds, and other common fasteners, may not be shown for clarity.
In preparation for use of the invention to be described below, a large release hole 11 is cut into one of the tanks on the submerged tanker or other vessel 10 using an ROV (in deep water) or by divers (at depths enabling diver operations). Immediately after the release hole 11 is formed, a closure mechanism is immediately installed on the vessel 10, such as a magnetic cap, valve, or other suitable device capable of substantially sealing the release hole 11, to prevent the premature release of fluids 12 through hole 11.
Turning now to the figures, a preferred embodiment of a subsea oil collector 1 is illustrated in an elevation view in
In the embodiment of
With specific reference to the container 2, inlet 3 may include a closure device or valve 7 which seals the container 2 at that location when closed, and which permits fluid 12 to enter container 2 when open. In typical applications, inlet 3 may range from 24 inches to 36 inches in diameter to accommodate the flow of fluids 12 released from hole 11, although the specific size may vary depending upon the precise needs of the situation. Similarly, outlet 4 also includes a closure device or valve 8 which remains closed as the container 2 is filled with fluid 12, but which can be opened to release the contents of the container 2 when it is retrieved. Both of closure devices 7, 8 may be opened and closed manually by divers or by an ROV, depending upon the depth of the water. Alternatively, either or both of closure devices 7, 8 can be opened or closed responsive to operating conditions or a fill condition of the container 2. For example, inlet closure device 7 may be caused to close by a motor or other common solenoid device upon an electronic signal generated from buoyancy sensors indicating that the container 2 is becoming completely filled with fluid 12.
Once the container 2 is positioned directly above the hole 11 or other leak source, the positioning device 5 is preferably attached to the vessel 10. This task would be performed either by divers at the site or by an ROV depending on the depth. The outlet closure device 8 is closed to seal outlet 4, and fluid 12 rises into the inlet 3 and displaces any water, if any, residing within the container 2. As the volume of fluid 12 increases within the container 2, water is continuously expelled through the inlet 3 until the container 2 is completely filled with fluid 12. Since the density of the oil is less than the density of the water, the oil will float to the top of container 2 while displacing the water to the bottom of container 2 and then out through inlet 3. When the container 2 is filled with fluid 12, the inlet 3 is closed. Next, the positioning device 5 is detached from the vessel 10 in preparation for retrieval of the fluid-filled container 2.
Preferably, the materials of construction of the container 2 and the positioning device 5 are such that the filled container 2 will ascend without assistance due to its increased buoyancy. If desired, additional flotation devices, such as buoyant materials commonly used for deep water marine applications, may also be installed onto the container 2.
With respect to the attachment and detachment of the positioning device 5, the positioning device 5 may also comprise mechanical devices or additional ropes or cables with anchors to ensure that the collector 1 is securely in place over the release hole 11. Alternatively, the positioning device 5 may be detached in response to some other condition, such as by the closing of inlet closure device 7 or by reaching a predetermined volume of fluid 12 within container 2. In either case, it is essential that the anchoring or attachment of the positioning device 5 be sufficiently secure to prevent the premature ascendence of the container 2 due to the increased buoyancy during collection of the fluid 12.
Although not required, the container 2 may be constructed from a tightly woven scrim that is permeable by water but not by the leaking fluid, e.g. crude oil. In this configuration, water can simply be passed through the sides of the container 2 as fluid 12 fills the container 2. Preferably, the top of the container 2 may be formed in the shape of an inverted cone, because the buoyancy forces applied to the top of the container 2 when filled will impart significant stresses to the fabricated container 2. Constructing the top of the container 2 in this manner should serve to minimize such stress and avoid possible tearing.
In
Finally,
In all of the above described embodiments, an offloading pump on board surface vessels 43 may be used to connect to the outlet 4 to pump out fluids 12 within the container 2. The fluids 12 may be pumped into towable bladders or into other barges on site. If necessary, a steam collar may be affixed to the outlet 4 to heat and facilitate offloading of highly viscous fluids 12. Also, the filled container 2 may be towed to land for offloading or transported on a vessel to port for offloading at another site.
Although exemplary embodiments of the present invention have been shown and described, many changes, modifications, and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of the invention. For example, the invention could be adapted to capture oil that rises from naturally occurring oil seeps in the ocean floor, by modifying the mounting device as necessary to attach to sea floor structures.
Claims
1. A subsea fluid collector, comprising:
- (a) a container having a fluid inlet;
- (b) a vessel positioning device connected to said container; and
- wherein said container is positioned by said vessel positioning device to receive, through said fluid inlet, a leaking fluid exiting out of a fluid leak source from a submerged vessel.
2. The subsea fluid collector of claim 1, wherein said inlet includes a closure mechanism adapted to prevent said fluids from escaping said container.
3. The subsea fluid collector of claim 1, wherein said container further includes a fluid outlet and an outlet closure device.
4. The subsea fluid collector of claim 1, wherein said container has negative buoyancy.
5. The subsea fluid collector of claim 1, further including:
- (a) a buoy residing at or near the surface of the water; and
- (b) a guide cable having a first end operatively attached to said buoy, and a second end operatively attached at or near said fluid leak source; and
- wherein said container is slidably attached to said guide cable.
6. The subsea fluid collector of claim 1, further including:
- (a) a floating fluid vessel residing at or near the surface of the water;
- (b) a cable having a first end operatively attached to said floating fluid vessel, and a second end operatively attached to said container; and
- (c) a conduit fluidically connected between said fluid outlet of said container and said floating fluid vessel, adapted to transfer fluids collected within said container into said floating fluid vessel.
7. The subsea fluid collector of claim 5, further including locking means for attaching said container to said submerged vessel.
8. The subsea fluid collector of claim 5, further including speed control means for controlling the speed at which said container slides along said cable.
9. The subsea fluid collector of claim 1, wherein said container includes a fluid outlet, and further including:
- (a) a first surface vessel residing at or near the surface of the water; and
- (b) a cable having a first end operatively attached to said first surface vessel, and a second end operatively attached to said container.
10. The subsea fluid collector of claim 9, wherein said first surface vessel includes an offloading port in fluidic communication with said outlet of said container to receive said fluids collected within said container.
11. The subsea fluid collector of claim 9, further including a second surface vessel having an offloading port in fluidic communication with said outlet of said container to receive said fluids collected within said container.
12. The subsea fluid collector of claim 10, further including surface vessel attachment means for securing said container to said first surface vessel during offloading of said fluids from said container.
13. The subsea fluid collector of claim 11, further including surface vessel attachment means for securing said container to said second surface vessel during offloading of said fluids from said container.
14. The subsea fluid collector of claim 9, wherein said first surface vessel includes means for reeling and unreeling said cable.
15. The subsea fluid collector of claim 1, further including:
- (a) a floating fluid vessel residing at or near the surface of the water; and
- (b) a guide cable having a first end operatively attached to said floating fluid vessel, and a second end operatively attached at or near said fluid leak source; and
- wherein said container is slidably attached to said guide cable.
16. The subsea fluid collector of claim 1, further including:
- (a) a floating fluid vessel residing at or near the surface of the water;
- (b) a ballast device attached to said container; and
- (c) a cable having a first end operatively attached to said floating fluid vessel, and a second end operatively attached to said ballast device.
17. The subsea fluid collector of claim 16, wherein said ballast device is a chain.
18. A method of collecting fluids below the sea, comprising the steps of:
- (a) providing a fluid collection container having a positioning device and a fluid inlet;
- (b) mounting said container using said positioning device to a submerged vessel having a fluid leak source and positioning said fluid inlet above said leak source;
- (c) permitting said leaking fluid to enter said container until said container is filled with said fluid; and
- (d) retrieving said container to a location at or near the surface of the sea.
19. The method of claim 18, wherein said container further includes a fluid outlet.
20. The method of claim 18, further including the step of closing said inlet prior to retrieving said container.
21. The method of claim 18, wherein said step of mounting said container to said submerged vessel includes removably attaching said positioning device to said submerged vessel.
22. The method of claim 18, wherein said step of retrieving said container from the sea includes detaching said positioning device from said submerged vessel.
23. The method of claim 18, wherein said container is slidably attached to a guide cable extending between said submerged vessel and a buoy positioned at or near the surface of the sea.
24. The method of claim 18, wherein said container is slidably attached to a guide cable extending between said submerged vessel and a floating fluid vessel at or near the surface of the sea.
25. The method of claim 18, wherein said container further includes a fluid conduit operatively attached between said container and a floating fluid vessel at or near the surface of the sea, and further including the step of transferring said fluid collected within said container to said floating fluid vessel via said fluid conduit, prior to retrieving said container.
26. The method of claim 18, wherein the step of retrieving said container comprises allowing said container to float to the surface of the sea.
27. The method of claim 18, wherein said container is slidably attached to a cable extending between said submerged vessel and a surface vessel.
28. The method of claim 18, wherein said container is attached to a cable extending from a surface vessel.
29. The method of claim 18, wherein prior to retrieving said container, said outlet of said container is connected to a surface vessel for offloading fluids from said container.
Type: Application
Filed: Dec 23, 2003
Publication Date: Feb 3, 2005
Inventor: Richard Lazes (Cornelius, NC)
Application Number: 10/744,937