Twin-hull offshore structure comprising an interconnecting central deck

Patent metadata

Field	Value
Publication number	US-9950774-B2
Application number	US-201415021958-A
Country	US
Kind code	B2
Filing date	Sep 18, 2014
Priority date	Sep 18, 2013
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A floating hydrocarbon processing/storage structure with a first and second assembly, each including a hull having side walls, one or more storage tanks and a deck structure, a connection structure interconnecting the hulls, processing equipment situated on the deck structures, at least one riser connected to a subsea hydrocarbon well and to the processing equipment and/or storage tanks, with a mooring system connecting the processing/storage structure to the sea bed, each hull including a hull deck structure bridging the side walls, the connection structure including a central deck extending at or near the height of the hull deck structures along at least 70% of the length of the hulls, the central deck supporting at least one of: risers vertically extending from the central deck between the hulls to the sea bed, fluid ducts horizontally supported on the central deck, and at least one drilling/work-over rig or crane.

First claim

The invention claimed is:

1. A floating hydrocarbon processing and storage structure comprising:
a first assembly and a second assembly each comprising a hull having spaced-apart side walls, one or more storage tanks, and a deck structure bridging the side walls;
a connection structure interconnecting the first and second hulls, the connection structure comprising
a central deck extending at or near the height of the hull deck structures along at least along 70% of the length of the hulls,
processing equipment situated on the deck structures, and
at least one hydrocarbon riser extending from the processing equipment or from the storage tanks of the floating hydrocarbon processing and storage structure to a subsea hydrocarbon well; and

a mooring system connecting the floating hydrocarbon processing and storage structure to the sea bed;
a track along an outer side of at least one of the hulls and along the central deck;
movable supports displaceable along each track; and
a lifting member extending between the supports and being displaceable over the respective deck structure.

2. The floating hydrocarbon processing and storage structure according to claim 1 , further comprising:
between the hulls, an intermediate bottom hull part, a bow hull part, an aft hull part, and at least one fluid storage tank comprised within a space between the two hulls underlying the central deck.

3. The floating hydrocarbon processing and storage structure according to claim 2 , wherein the central deck has a width between 0.2 and 0.5 of a width W of the hulls.

4. The floating hydrocarbon processing and storage structure according to claim 2 , wherein at least one of the hulls is provided along an outer wall thereof with an outboard riser supporting structure, supporting a plurality of risers.

5. The floating hydrocarbon processing and storage structure according to claim 2 , wherein the central deck supports one or more of
(i) a plurality of risers vertically extending from the central deck between the hulls to the sea bed, along at least one third of the length of the central deck, and
(ii) one or more of a plurality of risers and pipe elements horizontally supported on the central deck along at least one third of the length of the central deck.

6. The floating hydrocarbon processing and storage structure according to claim 1 , wherein the central deck has a width between 0.2 and 0.5 of a width W of the hulls.

7. The floating hydrocarbon processing and storage structure according to claim 6 , wherein at least one of the hulls is provided along an outer wall thereof with an outboard riser supporting structure, supporting a plurality of risers.

8. The floating hydrocarbon processing and storage structure according to claim 6 , wherein the central deck supports one or more of
(i) a plurality of risers vertically extending from the central deck between the hulls to the sea bed, along at least one third of the length of the central deck, and
(ii) one or more of a plurality of risers and pipe elements horizontally supported on the central deck along at least one third of the length of the central deck.

9. The floating hydrocarbon processing and storage structure according to claim 1 , wherein at least one of the hulls is provided along an outer wall thereof with an outboard riser supporting structure, supporting a plurality of risers.

10. The floating hydrocarbon processing and storage structure according to claim 9 , wherein the central deck supports one or more of
(i) a plurality of risers vertically extending from the central deck between the hulls to the sea bed, along at least one third of the length of the central deck, and
(ii) one or more of a plurality of risers and pipe elements horizontally supported on the central deck along at least one third of the length of the central deck.

11. The floating hydrocarbon processing and storage structure according to claim 1 , wherein the central deck supports one or more of
(i) a plurality of risers vertically extending from the central deck between the hulls to the sea bed, along at least one third of the length of the central deck, and
(ii) one or more of a plurality of risers and pipe elements horizontally supported on the central deck along at least one third of the length of the central deck.

12. The floating hydrocarbon processing and storage structure according to claim 11 , wherein the central deck supports the plurality of risers vertically extending from the central deck between the hulls to the sea bed, along half of a length thereof.

13. The floating hydrocarbon processing and storage structure according to claim 11 , wherein the central deck supports the one or more of the plurality of risers and the pipe elements horizontally supported on the central deck along half of a length thereof.

14. The floating hydrocarbon processing and storage structure according to claim 1 , wherein the mooring system comprises a turret carrying the at least one hydrocarbon riser, and connected to mooring lines that are moored to the sea bed, and
the connection structure comprises a bow deck structure rotatably connected to the turret and connected to the hull deck structures and to the central deck at or near the height of said hull deck structures.

15. The floating hydrocarbon processing and storage structure according to claim 14 , wherein the bow deck structure is connected to the hull deck structures along the combined width of the first and second hulls and the central deck.

16. The floating hydrocarbon processing and storage structure according to claim 15 , wherein the bow deck structure is connected to the hull deck structures along the combined width of the first and second hulls and the central deck.

17. The floating hydrocarbon processing and storage structure according to claim 14 , further comprising a bow structure extending from the bow deck structure to below the water line, and interconnecting with the side walls of the hulls to form a substantially closed bow.

Assignees

• Sbm Schiedam Bv
• Single Buoy Moorings

Inventors

• Brinkel Theodorus Johannes Bernardus
• Van Wijngaarden Willem Cornelis

Classifications

• B63B25/08

  fluid {(constructional features of bunkers B63B11/04; tanks for fuel or the like not forming bunkers B63B17/0027)} · CPC title

• B63B25/12

  closed · CPC title

• B63B1/125

  comprising more than two hulls (B63B1/107 takes precedence) · CPC title

• B63B21/507

  with mooring turrets · CPC title

• B63B35/44 Primary

  Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices {(construction methods for floating offshore platforms B63B75/00)} · CPC title