An ultra-deep sea offshore oil and gas dry production system and its installation and evacuation method

Abstract

The invention discloses an ultra-deep sea offshore oil and gas dry production system and its installation and evacuation method. The system includes a mobile oil production platform, dry production equipment, an underwater platform, a rigid riser system, a tension mooring system and an underwater wellhead system. The rigid riser system includes a lower rigid riser system and an upper rigid riser system. In the present invention, the ultra-deep sea production platform is designed as a mobile oil production platform and an underwater platform. Since the underwater platform bears the weight of the lower rigid riser system, the requirement of heavy production risers on the mobile oil production platform is reduced. The mobile oil production platform in the present invention realizes the expanded application of the shallow sea mobile oil production platform in the ultra-deep sea. Compared with the current ultra-deep sea oil production platform, the structure is simple and the construction cost is reduced. The mobile oil production platform in the present invention is installed on the underwater platform, so the complex mooring positioning system required by the current ultra-deep sea oil production platform is avoided.

Description

technical field [0001] The invention relates to an offshore oil and gas development technology, in particular to an offshore oil and gas dry production system for working in an ultra-deep sea environment and an installation and evacuation method thereof. Background technique [0002] The oil and gas resources in the South China Sea are extremely rich, and my country's oil and gas development in the ultra-deep sea area (water depth greater than 1,500 meters) in the South China Sea is still in its infancy. [0003] At present, the Chinese patent (patent number: ZL201110441883.6) discloses a new type of ultra-deep water oil and gas field engineering development system, which is mainly composed of a single riser support buoy and underwater oil production equipment, and can be used in shallow water (within 300 meters of water depth) The underwater oil production equipment is installed on the tension moored submerged buoy to realize the development of ultra-deep water oil and gas ...

AI Technical Summary

Problems solved by technology

[0004] First, because the system still uses an underwater production system, the cost of installation, use, and maintenance is high;

[0005] Second, due to the limited space on the upper deck of the submerged buoys of the system, these submerged production systems cannot be properly arranged on the buoys

[0007] First, since the system is located on an underwater platform at a depth of 100 to 400 meters underwater, the underwater wellhead cabin needs to withstand huge hydrostatic pressure;

[0008] Second, the underwater wellhead cabin is large in size, and each underwater well completion device requires a subsea wellhead cabin, so it is not conducive to the arrangement on the underwater platform;

[0009] Third, the system uses many instruments, complex structure and high cost

[0011] First, in current production practice, available dry oil and gas development equipment is limited to tension leg platforms and single column platforms;

[0012] Second, the ultra-deep sea catastrophic marine environment elements have high requirements for the design of dry oil and gas development equipment;

[0013] Third, limited by the depth of ultra-deep water, the high cost of the mooring system of the tension leg platform has become the main limiting factor for its development into ultra-deep water

The construction of the single-column platform is difficult, the vortex-induced vibration is obvious, and the anti-fatigue performance is poor

[0014] Fourth, under the ultra-deep sea environment, the installation and evacuation procedures of tension leg platforms and single-column platforms are complicated

[0015] Based on the above problems, the above-mentioned patents and traditional offshore oil and gas production systems cannot meet the requirements of the feasibility and economic applicability of using dry oil and gas development equipment in ultra-deep sea environments

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