Moored Wellhead Effluent Capture and Concrete Application Apparatus

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

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FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

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SEQUENCE LISTING OR TABLES

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BACKGROUND OF THE INVENTION

Field Of Invention

The present invention relates to the containment or recovery of liquids and gases erupting from a blown out oil well with emphasis on the containment method and apparatus used to secure a blowing wellhead or fissure in the sea floor and the conveyance of the hydrocarbons to the sea surface.

Insurmountable environmental damages, loss of natural resources and the loss of life are historic results of underwater oil well blowouts. The environmental impacts of such disastrous spills are noted through the loss of tourism and the use of fisheries, to the devastation of species and their habitat.

The companies financially responsible for the cleanup of the spills encounter enormous expenditures as a result of the attempted environmental cleanup and the litigations that represent the affected people and industries. The suspension of drilling operations and the tightening of regulations for drilling further exacerbates the finances of the responsible companies. Furthermore, the loss of the hydrocarbons which are not recovered for production further impacts the financial stability of the company due to lost revenue. As a result, a once thriving company which once provided financial security to many communities may become jeopardized, or worse, insolvent.

Therefore, it is the primary object of this invention to provide a new and improved effluent entrapment means for subsea blowouts. This invention addresses the issue of avoidable catastrophic environmental disasters as a result of wellhead blowouts by the capture of the hydrocarbons for use in post blowout conditions and improvement of the current drilling process technology by the addition of redundant systems and the offering of new features in non-blown out subsea installments.

An inverted open bottomed pressure vessel, the capture vessel, of dimensions to encompass subsea equipment, has a hole cut in the top to accept a vertical cylinder, mechanically attached to the center, with ample diameter through which the original well pipe can easily manipulate. Similarly, an outer dome, the vacuum vessel, of larger radius, has a hole cut to accept mechanical attachment through which the centerline vertical cylinder penetrates. Above the vacuum vessel, a cylinder is attached at an angle to the side of the center, vertical cylinder. The upper end of the center cylinder has a head with a hatch which can be remotely closed. The upper end to the auxiliary cylinder is topped with an auxiliary elbow, arranged such that acceptance of another pipe from a rig is possible, and a remotely controlled valve. Alternate topping arrangements to the auxiliary pipe are an alignment cone for remote aligning, threaded fitting, or pipe swaging apparatus.

The base of each vessel terminates on the same horizontal plane, and, as required, typical radial and concentric bulkheads are fit between the two dome vessels. Each bulkhead is fitted with air and fluid holes so that the flow of air, fluids, or concrete is not impeded. Extending below the plane and mechanically attached to each dome are cylinders with vertical axis and of corresponding radius. At the dome to cylinder joints, or as close to as practicable, a compression bar is placed on the outside surfaces of cylinders, parallel to the horizontal plane.

In addition to typical wellhead equipment, the following are added: gauges, cameras, lights, a hydraulic or pneumatic system, rams and actuators, necessary controls and wireless circuitry or tethers, a vacuum pump and required valves and equipment.

In use of the preferred embodiments, a tug, anchor handling offshore supply vessel, or a rig crane, with the apparatus hatch open and required tethers connected, lower the apparatus onto the existing pipe and into the water, using it as a guide to the wellhead. New pipe can be attached to the auxiliary pipe flange for a tandem pipe attachment/decent operation. A light and camera inspect the damaged pipe for obstructing defects during the decent. Once the above apparatus is in place above the blowing wellhead the decent is stopped and a remote robot removes the pipe from the damaged blowout preventer. Once removed, the apparatus is lowered around the blowout preventer and the pipe is pulled through the hatch. At this time, a vacuum is pulled on the space between the outer and inner vessels by evacuating water. This force pulls the cylindrical sections of the apparatus into the seabed to a depth of the compression bar at the dome to cylinder joints. With the vacuum remaining and verified by gauges, the hatch can be closed by remote control or robot sending the hydrocarbons into the auxiliary cylinder. If the auxiliary cylinder is not plumbed with pipe, the valve may be required to be open during the closing of the hatch to allow the effluent to escape.

BACKGROUND OF THE INVENTION

Objects and Advantages

Accordingly, besides the objects and advantages of the Method and Apparatus as described in my above patent, several objects and advantages of the present invention are:

• • a. The addition of the evacuation vessel to the original effluent containment arrangement, which has anchors at small tether angles to the horizontal plane, is that larger vertical forces from the fluid flow of the hydrocarbon can be overcome.
  • b. The integration of the hatch allows the exact placement of the apparatus assuming the original pipe remains tethered to the wellhead.
  • c. The pulling of the apparatus into the seabed effectively seals the wellhead allowing for 100% operable condition. Without containment vessel seal to the seabed a fraction of the hydrocarbons would escape.
  • d. Integration of existing or new pipes with several options as to how the connection may be made: threaded, or swage connection with a conical guidance system.
  • e. Remotely controlled hatch and vacuum devices allow for long-term operations without the need for a standby robot.
  • f. The addition of concrete into the space between the two vessels through an additional valve allows for long-term wellhead encasement solutions.
  • g. Cylindrical sections and compression rings add structural integrity, aid in the ease of deployment, and allow for ample safety factors for deep water wellheads.
  • h. Cameras and lights allow for troubleshooting, and aid in deployment.
  • i. The addition of adding structurally reinforced concrete in excavated cavities to encase subsea wellhead equipment or provide adequate foundations for such structures is aided by a lifting and securing device, excavation equipment, and concrete placement valves for use in new installations or expansions.
  • j. An additional evacuation valve connecting an auxiliary containment vessel to the capture vessel allows for the capture of effluent.

SUMMARY

In accordance with the present invention the Moored Wellhead Effluent Capture and Concrete Application Apparatus, is comprised of a capture vessel, an evacuation vessel, vertical chimney with dogged hatch, auxiliary chimney with shutoff valve, alignment cone and pipe receptacle, concrete fill nozzles with shutoff valves to the evacuation and capture vessels, hydraulic or pneumatic equipment and bulkheads as required, cameras, lights and support equipment as necessary, tether as necessary, instrumentation and required controls, and vacuum nozzle and support equipment. The successful construction and deployment of the apparatus allows for more successful capture of effluent and securing of the wellhead, and offers safer wellhead operation and encasement process of the drill pipe below the seabed.

DRAWINGS

Figures

FIG. 1 shows the elevation view of the apparatus with open hatch before the cutting of the original pipe and after the pulling of seawater from the evacuation vessel to lower the apparatus into the seabed in both the blown out and non-blown out configurations.

FIG. 2 shows the elevation view of the apparatus after the cutting of the original pipe, with closed hatch and after the installation of the new pipe in the blown out configuration.

FIG. 3 shows the plan view of the apparatus with closed hatch after the installation of the new pipe.

FIG. 4 shows the plan view of the apparatus with open hatch in the non-blowout installation.

FIG. 5 shows the elevation view of the auxiliary configuration of the apparatus with closed hatch pipe seal, lifting and securing device, excavation equipment, and effluent valve after the pulling of seawater from the evacuation vessel to lower the apparatus into the seabed in non-blown out configuration.

DRAWINGS

Reference Numerals

• 11 capture vessel dome
• 12 capture vessel cylinder
• 13 capture vessel compression bar
• 14 evacuation vessel dome
• 15 evacuation vessel cylinder
• 16 evacuation vessel compression bar
• 17 evacuation vessel bracket
• 18 radial bulkhead
• 19 concentric bulkhead
• 20 chimney cylinder
• 21 chimney head
• 22 hinged, dogged hatch
• 23 auxiliary chimney cylinder
• 24 auxiliary chimney shutoff valve
• 25 auxiliary chimney guide cone
• 26 auxiliary chimney receiving flange
• 27 evacuation and fill valve
• 28 control room watertight bulkheads
• 29 mechanical equipment
• 30 capture vessel concrete fill valve
• 31 evacuation vessel concrete fill valve
• 32 camera, light, and mounting bracket assembly
• 33 pressure sensor
• 34 original pipe
• 35 new pipe
• 36 drilled hole
• 37 concrete
• 38 subsea equipment
• 39 ballast
• 40 seabed
• 41 hatch to pipe seal
• 42 lift and securing device
• 43 effluent valve
• 44 excavation equipment

DETAILED DESCRIPTION

Preferred Embodiment—FIGS. 1 Through 3

The preferred embodiment of the present invention, Moored Wellhead Effluent Capture and Concrete Application Apparatus, is shown in FIG. 1, elevation, before the original pipe 34 is removed from the subsea equipment 38 in order to allow for the effluent to be diverted from the original pipe 34 to new pipe 35, as shown in FIGS. 2 and 3, elevation and plan, respectively. The capture vessel dome 11 is mechanically connected to capture vessel cylinder 12 forming an impervious connection resilient to high pressures. The capture vessel compression bar 13 rests on seabed 40 and is mechanically connected to capture vessel cylinder 12 or capture vessel dome 11 to assist in structural integrity. The evacuation vessel dome 14 and evacuation vessel cylinder 15 are mechanically connected forming an impervious connection resilient to high pressures. To assist in structural integrity and the resting of the Apparatus on the seabed 40, evacuation vessel compression bar 16 and evacuation vessel bracket 17 are mechanically connected to evacuation vessel dome 14 or evacuation vessel cylinder 15. To further assist in dealing with large hydrostatic and dynamic forces, radial bulkhead 18 and concentric bulkhead 19 are mechanically connected to capture vessel dome 11 and evacuation vessel dome 14. The chimney cylinder 20 is mechanically connected by an impervious joint at the top of capture vessel dome 11 and evacuation vessel dome 14 where holes are cut in capture vessel dome 11 and evacuation vessel dome 14 for the passage of chimney cylinder 20. Resting atop chimney cylinder 20 is the chimney head 21 mechanically connected by an impervious joint. Above the chimney head 21 is the hinged, dogged hatch 22 through which the original pipe 34 passes when open and is mechanically connected with an impervious joint to chimney head 21. Mechanically attached with an impervious connection in series to chimney cylinder 20 are auxiliary chimney cylinder 23, auxiliary chimney shutoff valve 24, auxiliary chimney guide cone 25 and auxiliary chimney receiving flange 26 for the redirection of effluent to a new pipe 35 once the original pipe 34 is disconnected to subsea equipment 38 and hinged, dogged hatch 22 is closed. Mechanically attached with an impervious connection to evacuation vessel dome 14 is evacuation and fill valve 27 for use to evacuate fluids from evacuation vessel dome 14 by mechanical equipment 29 in the control room watertight bulkheads 28 mechanically connected with an impervious connection to the Apparatus. Mechanically attached with an impervious connection to capture vessel dome 11 is capture vessel concrete fill valve 30, and the connection to evacuation vessel dome 14 is made with the evacuation vessel concrete fill valve 31. The camera, light, and mounting bracket assembly 32 is rigidly connected to the Apparatus at strategic locations. Similarly, pressure sensors 33 are placed at strategic locations for troubleshooting. Additionally, ballast 39 is placed on the Apparatus to assist in the capture vessel cylinder 12 and evacuation vessel cylinder 15 in making a good seal with the seabed 40 upon impact with said seabed 40.

Operation—FIGS. 1 Through 3

The operation of the preferred embodiment of the present invention, Moored Wellhead Effluent Capture and Concrete Application Apparatus, is shown in FIG. 1, elevation before the original pipe 34 is removed from the subsea equipment 38. The Apparatus deployment is from a workboat or oilrig crane via tether to contain blown out subsea equipment 38. The hinged, dogged hatch 22 is opened to allow the original pipe 34 is to be guided through the open bottom and to pass through the hinged, dogged hatch 22 while lowering the Apparatus. The Apparatus is then lowered into the water with capture vessel concrete fill valve 30 and evacuation vessel concrete fill valve 31 open to allow air to escape from the open bottom Apparatus. Once submerged, capture vessel concrete fill valve 30 and evacuation vessel concrete fill valve 31 are now closed in preparation of the encasement of the subsea equipment 38. A new pipe 35 may or may not be attached during the descent of the Apparatus and auxiliary chimney shutoff valve 24 should be open. The Apparatus then descends to the seabed 40 while being guided by the original pipe 34 where the subsea equipment 38 becomes encased by capture vessel cylinder 12 and the effluent becomes guided through chimney cylinder 20, chimney head 21, and then hinged, dogged hatch 22. Once the Apparatus is on the seabed 40 the evacuation and fill valve 27 evacuates water from the void space between capture vessel cylinder 12 and evacuation vessel cylinder 15 causing the hydrostatic pressure within the void to become less than the hydrostatic pressure head of the water above the evacuation vessel dome 14 resulting a net vertical force in the downward direction pushing the capture vessel cylinder 12 and evacuation vessel cylinder 15 into the seabed 40 until capture vessel compression bar 13 and evacuation vessel compression bar 16 are on seabed 40 and the subsea equipment 38 is encased inside of capture vessel dome 11. At this time the robot can remove the original pipe 34 from subsea equipment 38, causing the effluent to become more volatile, and the robot assisted or automatic closing of hinged, dogged hatch 22 can take place as shown in FIGS. 2 and 3, elevation and plan, respectively. Once the hinged, dogged hatch 22 is closed the effluent is then diverted to the auxiliary chimney cylinder 23 and to the new pipe 35.

Operation of Alternate Embodiments—FIGS. 1, 4, and 5

An alternate use of the invention is to deploy the Apparatus as in the preferred embodiment above before a blowout occurs from subsea equipment 38 or a drilled hole 36. Typically, the use would be such as shown in FIGS. 1 and 4, elevation and plan. In the event of such an occurrence, the procedure in the preferred embodiment could then be continued as in the preferred embodiment to capture any flowing hydrocarbons from subsea equipment 38 or drilled hole 36.

In addition to the auxiliary function of encasing the subsea equipment 38 in the event of a post-installation blowout, concrete 37 could be pumped into drilled hole 36 through capture vessel concrete fill valve 30, encasing new pipe 35. In the event of failed subsea equipment 38, concrete 37 could be pumped to fill the capture vessel dome 11, sealing off the subsea equipment 38 leak. The auxiliary configuration of FIG. 5 offers the means for deploying structural reinforcement by using lift and securing device 42. Furthermore, the lift and securing device 42 aids in the use of subsea excavation equipment 44.

Furthermore, the addition of a hatch to pipe seal 41, and an effluent valve 43 connected via a conduit to a an auxiliary containment vessel, the auxiliary apparatus configuration of FIG. 5, elevation, could capture smaller amounts of effluent while still offering the protection of the auxiliary chimney assembly for use in connecting an additional capture pipe.

The addition of the apparatus to existing and new wells makes the typical drilling operations safer and less prone to spills due to redundant systems, the ability to effectively deploy structurally reinforced encasement concrete and effluent capture technology.

ADVANTAGES

From the description above, a number of advantages of the Moored Wellhead Effluent Capture and Concrete Application Apparatus are:

• • a. The capture and containment of effluent as a result of a blown out wellhead or subsea equipment becomes more certain and reliable in the event of unstable seismic or pressure circumstances when the containment vessel, and the attached piping, are adequately moored to the seabed.
  • b. The Apparatus allows for the production of hydrocarbons to resume, once the system is fully installed and tested over a blowout, until redundant blowout systems can be installed or another well is drilled.
  • c. Concrete can be pumped into the void space between the two domes through the concrete valve effectively creating a more permanent structure.
  • d. In the event of the desired long term abandonment of the wellhead, concrete can be pumped through another valve into the capture dome sealing off the entire wellhead.
  • e. In new wells concrete can be pumped into the drilled hole encasing the well pipe reducing the affects of blowouts and the likelihood of oil spills.
  • f. Hole structural reinforcement can be deployed from the lifting and securing device as well as excavation equipment. As a result, larger reinforced foundations can be constructed for subsea and wellhead installations as well as offering additional means for excavation and access below these foundations.
  • g. Reversible vacuum pump and valve allow for the increase or decrease of pressure inside the void space under the evacuation dome resulting in a lift or descent of the apparatus.
  • h. By installing the Apparatus before the well goes into service auxiliary environmental protection and safety is offered by providing the ability to divert effluent emanating from blown out subsea equipment into the secondary manifold by disconnecting the original piping and closing the vertical manifold hatch.
  • i. In the auxiliary installation the addition of a pipe hatch seal to drill pipe, and an effluent valve attached to containment vessel via a conduit could serve as an additional measure against environmental containment.
  • j. With the installation of the auxiliary configuration, using a multitude of nested vessels, the auxiliary stack pipe connecting the capture vessel could serve as a secondary product conduit in tandem with the main central product conduit, thus serving as a separation pressure vessel.

CONCLUSION, RAMIFICATIONS, AND SCOPE

If offshore drilling is to advance in depth, volume, and is becoming more accepted in seismically and environmentally sensitive regions of the world, reliability of the equipment and the processes in which the industry relies upon will have to become less prone to catastrophic results due to the failure of any key component.