PLATFORM FOR CONTROLLED CONTAINMENT OF HYDROCARBONS

• US 20130084136A1
• Filed: 01/27/2011
• Published: 04/04/2013
• Est. Priority Date: 01/28/2010
• Status: Active Grant

• Current Assignee: Odfjell Drilling Technology Ltd. (Odfjell Drilling AS)
• Original Assignee: Odfjell Drilling Technology Ltd. (Odfjell Drilling AS)
• Inventors: Gudmestad, Ove Tobias, Albriktsen, Per, Losnedal, Frode, Farestveit, Robert, Skeie, Geir Morten
• Granted Patent: US 9,506,211 B2
• Time in Patent Office: Days
• US Class Current: 405/204
• CPC Class Codes: E02B 17/00 Artificial islands mounted on piles or like supports, e.g. platforms on raisable legs or offshore constructions; Construction methods therefor construction methods for floating platforms B63B75/00; anchoring floating platforms B63B21/00; floating platforms, e.g. anchored, B63B35/44; underwater reservoirs B65D88/78
• CPC Class Codes: E02B 17/0021 against ice-loads
• CPC Class Codes: E02B 17/02 placed by lowering the supporting construction to the bottom, e.g. with subsequent fixing thereto
• CPC Class Codes: E02B 2017/0043 Placing the offshore structure on a pre-installed foundation structure
• CPC Class Codes: E02B 2017/0052 Removal or dismantling of offshore structures from their offshore location
• CPC Class Codes: E02B 2017/0069 Gravity structures
• CPC Class Codes: E02B 2017/0086 Large footings connecting several legs or serving as a reservoir for the storage of oil or gas
• CPC Class Codes: E21B 43/0122 Collecting oil or the like from a submerged leakage cleaning or keeping clear the surface of open water from oil or the like E02B15/04
• CPC Class Codes: Y02A 20/204 Keeping clear the surface of open water from oil spills

Abstract

The invention relates to a concept for controlled containment of oil and condensate and possibly other types of liquids and chemicals in constructions as a possible failure of the conventional prior art barriers used in offshore petroleum exploration and production activities, intended for use at several water depths. The concept comprises a support structure (10) and a deck structure (14) positioned on top of the support structure (10), from where drilling may be performed, and where possible spillage of hydrocarbons from the drilling or production activities, in case of failure of the conventional barriers, will be contained and directed in a controlled manner to collecting storage tanks (46) integrated in the support structure (10).

Claims

1. Platform for controlled containment of oil and condensate and possible other types of liquids and chemicals in the platform in case of a failure of the barriers used in the offshore petroleum industry, intended to be used on varying water depths, characterized in that the platform comprises a supporting structure and a deck superstructure positioned on top of the support structure, from where drilling may be performed, and where hydrocarbons which possibly is leaked from the drilling operation caused by failure of the conventional barriers, is contained and directed to collecting tanks which form an integrated part of the support structure, the platform comprising a base structure intended to rest on the seabed, and a number of separate buoyancy bodies placed on top of each other and interlocked, resting on the base structure by means of the weight of the buoyancy bodies, the buoyancy bodies also being interlocked to the base structure by means of vertically tensioned cables evenly arranged around the periphery of the platform, and a plurality of mooring cables anchored to the sea bed at large distance from the platform, the mooring cables being connected to the platform via fairleads and winches.

2. Platform according to claim 1, wherein the vertically tensioned cables at one end are connected to the base structure and at the opposite ends connected to winches on the deck structure via fairleads.

3. Platform according to claim 1, wherein the base structure is fixed to the seabed by means of a plurality of piles or conductor tubes, pressed and cemented seep down into the seabed.

4. Platform according to claim 3, wherein the fixing point for the vertically tensioned cables coincide with the upper ends of the piles or conductor tubes.

5. Platform according to claim 1, wherein locking tie rods movably arranged in conductor ducts and extending across a joint between two consecutive platform sections are used, each locking tie rod at its upper and lower end being provided with locking surfaces co-functioning with corresponding locking surfaces in the conductor ducts, the locking effect being provided by rotating the locking tie rod with respect to the duct.

6. Platform according to claim 1, wherein the various construction elements forming the supporting structure comprises of independent units which may be maneuvered independently, mainly by towing and ballasting.

7. Platform according to claim 1, wherein the various construction elements forming the supporting structure may be assembled by means of guiding means or dowels and corresponding openings or recesses in the elements position over or below the guiding means or dowels.

8. Platform according to claim 1, wherein all elements forming the support structure, are provided with vertical openings (drilling shafts) extending in aligned manner through the platform, for positioning of wells and well recesses in the lower part of the basis structure, and further with drilling equipment positioned on top of the deck structure.

9. Platform according to claim 1, wherein the drilling shafts are configured so that the joints during assembling is sealed such that watertight integrity for the shafts are established.

10. Platform according to claim 1, wherein a cutoff valve is positioned in the base structure as an extra barrier for a high pressure riser, the riser being terminated at deck level by a blowout preventer (BOP) and a valve assembly.