Sea vessel docking station

Abstract

A system and method in which a buoyant central docking station captures, lifts and couples one or more other sea vessels is disclosed, wherein a flexible, modularized production system is quickly realized on a cost effective basis. The capabilities of a number of older, less expensive, readily available vessels are combined to achieve an effective FPSO substitute that allows lower producing fields to be explored and produced in a profitable manner. The time horizon between initiation and consummation of field operations is reduced, and older vessels that might otherwise be scrapped or retired are again made useful and seaworthy in a safe and profitable exploration and production environment.

Description

STATEMENT OF RELATED CASES [0001] The present application claims the benefit of prior provisional application No. 60 / 695,727, filed Jun. 29, 2005.BACKGROUND OF THE INVENTION [0002] The present invention relates generally to offshore oil and gas exploration and production systems, and in a specific, non-limiting embodiment, to a system and method of capturing, lifting and coupling a plurality of sea vessels using a centralized wet docking station, so that relative deck sizes are effectively increased, and equipment packages and other facilities are exchanged between the decks of captured vessels in a stable and efficient manner. BACKGROUND OF THE INVENTION [0003] Innumerable systems and methods have been employed in efforts to find and recover hydrocarbon reserves around the world. At first, such efforts were limited to land operations involving simple but effective drilling methods that satisfactorily recovered reserves from large, productive fields. As the number of known producing...

AI Technical Summary

Benefits of technology

"The patent describes a wet docking station for exploring and producing offshore energy sites. The station includes a buoyant central docking station and an adjustable buoyancy chamber to control its buoyancy. It also has at least one subordinate docking station to capture and lift sea vessels. The technical effect of this invention is to provide a more efficient and flexible way to explore and produce energy from offshore sites."

Problems solved by technology

At first, such efforts were limited to land operations involving simple but effective drilling methods that satisfactorily recovered reserves from large, productive fields.

Initially, deepwater exploration and production efforts consisted of expensive, large scale drilling operations supported by tanker storage and transportation systems, due primarily to the fact that most offshore drilling sites are associated with difficult and hazardous sea conditions, and thus large scale operations provided the most stable and cost-effective manner in which to search for and recover hydrocarbon reserves.

A major drawback to the large-scale paradigm, however, is that explorers and producers have little financial incentive to work smaller reserves, since potential financial recovery is generally offset by the lengthy delay between exploration and production (approximately 3 to 10 years), and by the large capital investment required for conventional platforms and related drilling, production and transportation equipment.

Moreover, complex regulatory controls and industry-wide risk aversion have led to standardization, leaving operators with few opportunities to significantly alter the prevailing paradigm.

As a result, offshore drilling operations have traditionally been burdened with long delays between investment and profit, excessive cost overruns, and slow, inflexible recovery strategies dictated by the operational environment.

However, since lognormal distributions of recoverable reserves tend to be spread over a large number of small fields, each of which yield less than would normally be required in order to justify the expense of a conventional large-scale operation, most such regions have to date been underexplored and underproduced relative to their potential.

Consequently, many potentially productive smaller fields have already been discovered, but remain undeveloped due to economic considerations.

Currently, most deep water exploration and production operations are facilitated by means of a large, expensive floating production and storage offtake (FPSO) vessel, which is used to arrange and store essentially all of the facilities and equipment packages likely to be required aboard a single ship, with lesser vessels being employed only in support roles for purposes such as transporting crews back and forth from shore, delivery of new or replacement equipment packages, etc.

For example, a modern FPSO can take as long as eight to ten years from start-up to completion before it can be used at sea, and the total cost associated with manufacturing the vessel can run in excess of one billion dollars.

Moreover, since an FPSO is so large and expensive to manufacture, only very large field operations (e.g., those producing about 50,000 barrels a day or more) will economically justify an operator's investment in such a vessel.

Consequently, a great many lesser fields (for example, fields have the capacity to yield only about 10,000 barrels a day) are known by explorers to contain reserves, but are not being worked by producers because the cost of production using an FPSO would exceed the profits that could be obtained from recoverable reserves.

The Wiking system is deficient, however, in that it is useful “only for small vessels,” lacks the buoyant capacity to capture and lift vessels of any significant size and weight (which is, of course, a critical aspect of any modern exploration and production system), and utterly fails to contemplate the coupling of multiple deck surfaces in order to form a larger, unified deck from which exploration and production operations can be carried out.

Similarly, U.S. Pat. No. 6,336,419 to Breivik discloses a barge having one or more docking stations formed at either end in which captive ships can be docked, but fails to appreciate the advantages of lifting and coupling two or more vessels so that their respective deck surfaces are combined into a larger, unitary surface from which exploration and production operations can be carried out with maximum efficiency and safety.

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