Subsea deepwater petroleum fluid spill containment

Abstract

A subsea deepwater petroleum fluid spill containment device that can be quickly deployed to the site of a deepwater well blowout or similar eruption of petroleum fluids on or near the ocean floor to be sunk and positioned over the eruption, capture the petroleum fluid preventing it entering and polluting the environment, separate the constituents of oil, water and gas into disparate components subsea and inside of the collection device clean them, deliver the clean produced water to the subsea water and utilizing the hydraulic hydrostatic head pressure of the waters depth, if at least 4500 feet deep, deliver dewatered oil to surface storage with sufficient pressure to eliminate the need for mechanical pumping and the filtered gas at sufficient pressure for storage in a CNG container ship.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the capture and containment in deepwater, subsea, of oil, water and gas in the event of a well blowout, or other such subsea leakage, to prevent the entry of potentially contaminating fluids into the environment.

2. Discussion of Prior Art

Hammett U.S. Pat. No. 4,324,505 describes a type of method and apparatus that can be used to capture petroleum fluids erupting from a well blowout or similar petroleum leak subsea. Emphasis is placed on the placement of a device over the well that will capture fluids erupting from a blowout receiving the full flow of the fluids and delivering them as a mixture, together, to surface support equipment.

Other U.S. patents such as Gonzalez U.S. Pat. No. 6,276,455, Subsea Gas Separating System; Houot U.S. Pat. No. 4,982,794, Apparatus For Oil/Gas Separation At An Underwater Well-Head; Charpentier U.S. Pat. No. 3,875,998, Installation For Separation On The Seabed Of The Effluents From Underwater Oil Wells; and Boyce U.S. Pat. No. 7,487,836, Riserless Modular Subsea Well Intervention Method and Apparatus, teach means and methods of receiving a mixture of petroleum fluids, subsea, and separating them into disparate products such as oil, water and gas, but none teach their application, or anticipate the use, in any form, of the inventions in capturing and containing petroleum fluids, subsea, erupting from a deepwater well blowout or from a similar leakage.

3. Discussion of the Present Invention

My invention teaches a method and apparatus for capturing and containing, subsea, in deepwater, the unexpected outflow of potentially contaminating petroleum fluids such as oil, water and gas erupting from a well blowout or similar leakage. It teaches the configuration and construction of a device that can be quickly deployed, placed over the erupting fluid and commissioned in a manner that will capture and contain all of the fluids and further will do so in a manner whereby the fluids will be separated and cleansed, subsea, within the containment device, and utilizing the hydrostatic head pressure of the deepwater, delivered, separately, to the surface of the deepwater with sufficient pressure for handling and storage of the oil and gas in sea going containment vessels. The lack of any functional method and apparatus of the type taught by my invention being presently available is evidenced by the disastrous amount of contamination that resulted from the blowout of the Macondo deepwater well in the Gulf of Mexico, April 2010, before the blowout could be contained by plugging, while, in the meantime, a vast amount of petroleum fluid erupted into the environment. Further, even though a containment device, as taught by the aforementioned Hammett patent, was hurriedly fabricated, after the blowout had occurred, and deployed, it proved to be incapable of capturing and containing the erupting petroleum fluids.

As evidenced by the lack of a deepwater collection and containment device that can capture and separate, subsea, fluids erupting, in deepwater, upstream and/or away from the BOP and the wellhead, being included as part of the array of equipment that has been recently assembled, under the guidance of the exploration and production companies, in an attempt to prevent disastrous contamination in the event of another deepwater well blowout, and to comply with the government requirement of a method and means for containment of a deepwater well blowout as part of the drilling permit process, there is no method and apparatus, presently available, as taught by my invention.

SUMMARY OF THE INVENTION

It is the objective of the present invention to teach a subsea deepwater petroleum fluid spill collection and containment method and apparatus that will capture and contain, subsea, in deepwater, all of the petroleum fluids erupting from a deepwater well blowout thereby prohibiting the potential contamination of the environment. Further objective is that the apparatus be capable of deployment and commissioning quickly to mitigate the potential pollution that will occur while waiting on the commissioning. Still further objective is to teach a configuration of the apparatus that will capture all of the erupting fluids and separate, within the said apparatus, subsea, the oil, water and gas and cleanse them sufficiently for the produced water to be returned to the sea, and the oil and gas delivered separately, utilizing the hydrostatic head pressure of the deepwater, to surface containment vessels without the application of mechanical pumps. The teaching of this new and most efficient and effective method and means for capturing and processing petroleum fluids erupting from a deepwater well blowout or similar leakage and the uniqueness of the configuration of the apparatus and the novelty of its internal structures and appurtenances will become apparent upon a study of the drawing of the preferred embodiment, and a reading of the description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWING

The drawing is an isometric depiction of the preferred embodiment of the apparatus, illustrating a cylindrical elongated shape and the novel and effective internal structures contained therein, whereby, the new, unique, and efficient method of capturing and containing petroleum fluids erupting, subsea from a deepwater well blowout or similar leakage, to prevent potential pollution of the environment, is accomplished.

DESCRIPTION OF THE INVENTION

Referring to the drawing the apparatus consists of a cylindrical elongated vessel 1 with a vertical centerline constructed from high strength sturdy materials such as carbon steel thick enough to withstand a substantial internal explosion and remain intact and also heavy enough for the weight of said sturdy materials to counterbalance, at least part of, the buoyancy of the lighter than water petroleum fluid that will be captured and contained inside of said apparatus. The said vessel will be substantially open on the bottom 2 and closed on the top 3 and there will be a plurality of partial bulkheads, 4a, 4b, (4c & 4d not shown), and 4e, serving to absorb the force of the erupted flow of said petroleum fluid and impart a horizontal flow pattern for more efficient separation of the oil, water and gas constituents of the said petroleum fluid. There will be a vertical retaining cylinder 5, open on both ends, centered within, and structurally attached near the open bottom of said apparatus for the purpose of directing the bulk of the turbulent erupting fluid flow to the center of said apparatus. The separated water constituent will settle back into the sea via a quiescent annular space 6 formed between the inside wall of said apparatus and the outside wall of said retaining cylinder. There will be an oil outlet conduit 7 located in an upper region of said apparatus, and a gas outlet conduit 8 located on the top closure of said apparatus. There can be a device 9 to extract liquid from the gas constituent prior to its exiting conduit 8 and a coalescing device(s) 10 to assist the separation of the oil and water constituents from one another as said petroleum fluid traverses the horizontal flow path. Other internal appurtenances include an internal gas venting conduit 11, an internal water draining conduit 12, and a bottom stiffener ring 13. There will be a gas/oil interface sensor 14, an oil/water interface sensor 15. Said apparatus may also be equipped with adjustable supporting legs 16 and adjustable supporting stabilizers 17 and include means for adding dead weight to overcome buoyancy and maintain the stability of said structure when it is positioned over said erupting petroleum fluids.

Said apparatus, upon fabrication, can be retained at a coastal location in proximity to the offshore drilling sites and be deployed by floating with the bottom end 2 partially capped while laying on its side and being towed to the location of a subsea deepwater eruption of petroleum fluid. The said apparatus will be uprighted and lowered over the eruption by removing said partial cap and venting air from the top closure 3 to permit the intake of water of sufficient quantity to attain the proper weight for allowing the said apparatus to sink in a vertical position while being guided by a hoisting crane and an underwater camera. The positioning and commissioning of said apparatus may require the temporary release of some pent up energy of the erupting flow of said petroleum fluids through the opening of emergency vent hatches (not shown). Also there may be a means for opening the said emergency hatches to release petroleum fluids if the said apparatus becomes buoyant enough to otherwise float away from the site of the eruption. It is important that the said apparatus be volumetrically large enough to absorb the full energy potential of said erupting petroleum fluid and be able to contain hydrates that are likely to form from the flowing combination of hydrocarbons and water in the presence of high pressure and low temperature without becoming plugged up. There can be included the means for adding heat and or chemical hydrate inhibitors.

In operation the said constituents of the said erupting petroleum fluid will stratify inside of the said apparatus, forming a water phase in the lower region, an oil pad in the central and upper region and a gas pad near the top closure 3. Thereby from the stratified fluid reservoirs the cleansed water will be returned to the sea, the de-watered oil delivered to a tanker or barge and the cleansed gas, compressed by the deepwater hydrostatic head, delivered to a compressed natural gas container ship. Thence, once the said apparatus is in place, positioned over the eruption of said petroleum fluids and commissioned, no pollution should result through the discharge of the said petroleum fluids directly into the sea.

Claims

1. A method of capturing and containing, subsea, petroleum fluid, consisting of a mixture of oil, water and gas, erupting from the blowout of a deepwater well or similar leakage, said method preventing the pollution of the environment by the said petroleum fluid through the construction, deployment and commissioning of a uniquely configured, large cylindrical elongated vertical vessel with a substantially open bottom end and closed top end placed, subsea, directly over the erupting said petroleum fluid so as to capture the oil, water and gas constituents of the said petroleum fluid, inside the said vessel, wherein they are then separated and deposited in stratified sequence comprising a water phase occupying the bottom region, a gas pad extending from the said closed top end down to a level somewhat below the said closed top end and a pad of oil extending from the bottom level of the said gas pad to the top level of the said water phase and including a conduit attached to the said closed top end for delivery of the gas from the vessel and another conduit attached to a side wall of the said vessel in the upper region of the said pad of oil for separate delivery from the said vessel of the said oil, with both the said gas and the said oil being discharged from the said vessel at a substantial pressure created by the hydrostatic hydraulic head pressure of the deepwater communicating to the inside of the vessel through the said substantially open bottom to thereby compress the said stratified fluids inside of the said vessel.

2. The method of claim 1 wherein the said vessel contains a multiplicity of partial bulkheads installed inside, transverse to the flow of the said erupting petroleum fluid for the purpose of slowing the momentum, absorbing the pent up energy, trapping the gas and/or water, and establishing a substantially horizontal flow path inside the said vertical vessel.

3. The method of claim 2 including at least one conduit attached to one or more of the said partial bulkheads for the purpose of transporting said gas, that has been trapped, to the said gas pad and at least one additional conduit attached to one or more said partial bulkheads for the purpose of transporting said water, that has been trapped, to the said water phase.

4. The method of claim 1 wherein there is also a vertical cylindrical retainer device open on both ends structurally supported off the side wall of the said vessel and placed inside of the said vessel and having a diameter smaller than the inside diameter of the said vessel with its lower end near the substantially open bottom end of the said vessel and its upper end a few feet above the said lower end and a stiffener ring attached to the said substantially open bottom end of the said vertical vessel.

5. The method of claim 2 wherein there is also one or more coalescing means operating in conjunction with the said partial bulk heads for the purpose of augmenting the separation process through enlarging the particle size of non-continuous phase fluids which will speed up the gravity separation rate.

6. The method of claim 1 wherein there is also a mist extraction device through which the gas must pass as it exits the said vessel.

7. The method of claim one whereby there is also included sensors to detect the gas/oil interface and thereby control the level of the said gas/oil interface and to detect the oil/water interface and thereby control the water level.

8. The method of claim one and also including adjustable supporting legs and/or adjustable stabilizers whereby the said distance between the subsea floor and the said substantially open bottom end of the said vessel can be adjusted and the stability of the said large cylindrical elongated vertical vessel can be enhanced.

9. The method of claim 1 whereby the said vertical vessel construction will include an automated air and water filling and venting means in order for the said vertical vessel to be stored at a coastal location in proximity to the offshore drilling sites and be deployed relatively quickly to the location of a subsea deepwater eruption by capping the said substantially open bottom end of the said vertical vessel and towing it to the location with the said vessel laying horizontally and with proper ballast by utilizing the said automated air and water filling and venting system, floating horizontal and then by removing the said bottom end cap, right the said vertical vessel by venting air and taking on water to attain the desired lifting weight as the said vessel sinks in the vertical position and, using a lifting crane and underwater cameras, position the said vertical vessel directly over the said eruption, and once in place external dead weight may be added to the said vertical vessel to offset the buoyancy created by the captured petroleum fluids collecting inside and to enhance the overall stability of the said large cylindrical elongated vertical vessel and the said vertical vessel construction may also include several emergency hatches since, as the said vertical vessel is being positioned over the said eruption, it may be necessary to open the said emergency hatches, temporarily, to release pent up energy or in the event the said vertical vessel becomes too buoyant it may be necessary to temporarily vent some of the said gas to keep the said vessel from floating away.

10. Apparatus for the capturing, containing, and processing, subsea, in deepwater, all of the outflow of the potentially contaminating petroleum fluid, consisting of a mixture of oil, water, and gas, erupting from a deepwater well blowout or similar leakage, said apparatus comprised of a large cylindrical vertical vessel, closed on the top end and open on the bottom end, positioned directly above the eruption that is emitting the said oil, water, and gas, said vertical vessel configured to accommodate the steps of separating the oil, water and gas and establishing three disparate strata, one strata on top of the other with a water phase on the bottom, an oil phase in the middle, and a gas phase on top, and including a multiplicity of internal partial bulkheads positioned to establish a horizontal flow pattern as the fluids traverse the vessel flow path, also there are at least two interface sensors one, located at the gas/oil interface, that sends a signal to a flow control valve on the gas discharge conduit causing it to open when the oil/gas interface lowers and another one, located at the oil/water interface that sends a signal to a flow control valve on the oil discharge conduit causing it to open when the oil/water interface lowers and water is discharged through the said bottom opening which also communicates the deepwater hydraulic hydrostatic head pressure as the driving force to deliver the gas and oil separately, the gas at high pressure to a sea going compressed natural gas container ship and the oil at moderate pressure to a sea going tanker or a barge, for storage and commercial sale.

11. The apparatus of claim 10 and including a cylindrical longitudinal retaining ring of smaller diameter than the said vertical vessel diameter and open on both ends with its lower end located near said vertical vessel bottom open end and its upper end a few feet higher than its lower end and said retainer ring centrally suspended within the interior of the said vertical vessel supported by structural members attached to the outside wall of the said retaining ring and the inside wall of the said vertical vessel, and also there can be a means attached in perpendicular transverse relationship to at least one of the said multiplicity of internal partial bulkheads for causing coalescence of the non continuous phase fluid particles to enhance the gravity separation and may also include a mist extracting device through which the said gas must pass when exiting the said vertical vessel and wherein one or more of the said multiplicity of internal partial bulkheads may perform as gas traps and/or water traps one or more internal vertical conduit may extend from the said gas trap into the said vertical vessel said gas space and additionally one or more internal vertical conduit may extend from said water trap into the said water space of said vertical vessel.

12. The apparatus of claim 10 including, attached to the said bottom open end, a structural stiffener ring around the circumference of the inside wall of the said vertical vessel, and attached to the said circumference of the outside wall a multiplicity of adjustable legs and/or adjustable stabilizers and further there may need to be included a means for externally attaching dead weight to anchor the said vertical vessel firmly on the deepwater seabed and there may also be included, as part of the said apparatus, ancillary appurtenances, means for emergency venting of pent up energy and/or said gas to reduce the buoyancy of the said vertical vessel.

13. A device, for capturing petroleum fluids erupting subsea on or near the ocean floor in deep water as associated with a well blowout or similar leakage, comprising: a large cylindrical elongated vertical vessel of sturdy construction with a long cylindrical side wall, a closed top end and open bottom end, and including internally, a multiplicity of horizontally positioned spaced apart partial bulkheads open on only one chord edge, attached to the said side wall of said vertical vessel positioned one above the other with the open end alternating, and also a vertical straight sided elongate cylindrical shape retaining ring of sturdy construction with its diameter smaller than the inside diameter of the said vertical vessel, open on both ends, centered and structurally supported off of the said vertical vessel said inside side wall, with its bottom end at a level close to that of the bottom end of said vertical vessel and its top end a few foot of length above the bottom end, also attached to and penetrating the said closed top end of said vertical vessel a conduit through which fluid can escape and attached to and penetrating the said side wall of said vertical vessel located a few feet of length below the closed top end of said vertical vessel another conduit through which fluid can escape, and also including, integral to the operation of the subject device, at least two electronic interface sensors installed at various locations that can, with the subject device in operation, detect the level of fluids on the inside of said vertical vessel.

14. The device of claim 13 also including a permeable coalescing device, installed in perpendicular relationship between at least two of the said partial bulkheads, traversing the full inside width of the said vertical vessel.

15. The device of claim 13 also including a mist extractor unit installed inside the said vertical vessel in proximity of the said conduit penetrating the said closed top end of said vertical vessel.

16. The device of claim 13 also including one or more vertically oriented conduits attached to and penetrating one or more of the said partial bulk heads, said conduit may provide, when the subject device is operating and its length extends to proximity of the said closed top end, vapor venting, and/or its length extends to proximity of the said open end of the said vertical vessel, water draining.

17. The device of claim 13 may also include a stiffener ring near and attached to the said open end of the said vertical vessel and also a multiplicity of adjustable supporting legs and/or adjustable stabilizing means and may also include means for adding dead weight to the subject device.