Cylindrical FPSO design method and device suitable for trunk tree oil extraction system, medium and equipment

Abstract

The invention discloses a cylindrical FPSO design method suitable for a dry tree oil extraction system. The method comprises the following steps that a ship body is designed; designing a main scale; designing an oil extraction moon pool system; motion performance design; designing a positioning system; and subdivision design. The method can be used for guiding the design of the dry tree cylindrical FPSO with the functions of well drilling, oil extraction, oil storage, oil unloading and the like, the investment of one floating facility can be reduced, the safety in the crude oil production, storage and output process is guaranteed, the development requirement of the deepwater isolated oil field is better met, and economic development of the deepwater isolated oil field is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of offshore oil development, and in particular relates to a design method, device, medium and equipment for a cylindrical FPSO suitable for a dry tree oil production system. Background Art

[0002] Isolated deepwater oilfields have small reserves, low cumulative production, and poor oil quality, requiring frequent workovers. Economical development requires significantly reducing engineering facility investment. Traditional development models require two floating production facilities (FPVs): one for production, storage, and unloading, and the other for drilling and workovers.

[0003] In recent years, FPSOs (Floating Production Storage and Offloading) have been widely used in offshore oil and gas development, becoming the most numerous floating platform type in service worldwide. However, because the kinematic performance of traditional FPSOs cannot meet the precision control requirements of drilling equipment and dry-tree production systems, they are used exclusively as floating production storage and offloading vessels. Their topsides house only oil and gas processing facilities, not dry-tree production systems. Oilfield development and utilization must be coordinated with jacket platforms or wet-tree production trees. This development model results in long construction cycles and high overall investment, making it difficult to economically develop isolated deepwater oilfields. Summary of the Invention

[0004] The present invention aims to address at least one of the technical problems existing in the prior art. To this end, the present invention provides a design method for a cylindrical FPSO suitable for a dry-tree oil production system. The method is intended to guide the design of a dry-tree cylindrical FPSO capable of drilling, oil production, storage, and unloading, thereby better meeting the development needs of isolated deepwater oilfields.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a method for designing a cylindrical FPSO suitable for a dry tree oil production system, comprising the following steps: hull design; Main scale design; Oil production moon pool system design; sports performance design; Positioning system design; Compartment design. Preferably, the designed hull includes a heave body, a frustoconical transition section, a cylindrical barrel and an outboard structure connected in sequence from bottom to top, a main deck is arranged on the top of the outboard structure, and an upper module for oil and gas production and crude oil storage and an outboard station for crude oil export are arranged on the main deck.

[0006] As a preference: when carrying out the main scale design, the following sub-steps are included: Determine development requirements and related parameters: Based on the development requirements of the target oilfield, determine the weight of the upper module and the number of development wellheads, as well as the size of the moon pool; Determine the height of the main deck: Determine the height of the main deck from the water surface based on the environmental conditions of the target oil field; Determine the diameter of the heave body: Determine the diameter of the heave body according to the width of the dock; Determine other dimensions: set the hull draft, heave body height, truncated cone transition section height, cylindrical body height, damping plate width, and flared structure height; Determine the main dimensions: set the diameter of the cylindrical barrel; Preliminary stability calculation: select the hull structure weight based on experience, and use the ship static stability calculation method to preliminarily calculate the hull stability under in-position conditions and towing conditions; Stability optimization: adjust the scale of each hull component and recalculate the hull stability under in-position and towing conditions; Motion performance calculation: Calculate the natural period of motion of cylindrical FPSO based on the calculation method of natural period of rigid body motion in rigid body dynamics; Iterative optimization: Iterate the above steps to determine the main scale design scheme of the cylindrical FPSO suitable for the dry tree oil production system.

[0007] As a preferred embodiment, when designing the oil production moonpool system, a moonpool is provided in the frustoconical transition section and the cylindrical body, which is connected vertically and serves as a passage for the tensioned riser. The tensioned riser is deployed in the moonpool and connected to the dry oil production system in the upper module and the subsea wellhead. The cross section of the moonpool is set according to the requirements of the tensioned riser. At the same time, in order to avoid interference between the tensioned riser and the hull, the moonpool 11 is set to a downward trumpet shape.

[0008] As a preferred option: when designing the motion performance, a number of damping plates are arranged at intervals along the circumferential direction on the outer side of the cylindrical shell to improve the motion performance of the hull and ensure long-term safe production.

[0009] As a preference, when designing the positioning system, an anchoring device is arranged outside the cylindrical shell to position the hull, and the anchoring device can be composed of multiple mooring cables.

[0010] As a preferred option: when designing the compartments, oil storage tanks and ballast tanks are set up in the cone-shaped transition section and the cylindrical body, which are connected vertically and distributed along the circumference. The ballast tank is arranged on the outside of the oil storage tank, and the volumes of the ballast tank and the oil storage tank are optimized. Then, a specially designed loading computer is used to pre-calculate and adjust the ballast water to ensure that the storage and output of crude oil and the overall draft of the platform remain constant throughout the service life.

[0011] In a second aspect, the present invention provides a cylindrical FPSO design device suitable for a dry tree oil production system, comprising: A first processing unit for performing hull design; The second processing unit is used for performing main scale design; The third processing unit is used to design the oil production moon pool system; a fourth processing unit, for performing motion performance design; a fifth processing unit, configured to design a positioning system; The sixth processing unit is used for performing compartment design.

[0012] In a third aspect, the present invention provides a computer storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the cylindrical FPSO design method described in the first aspect of the present invention.

[0013] In a fourth aspect, the present invention provides a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the cylindrical FPSO design method described in the first aspect of the present invention are implemented.

[0014] The present invention has the following advantages due to the adoption of the above technical solution: The present invention can be used to guide the design of a trunk-tree cylindrical FPSO with the functions of drilling, oil production, oil storage, and oil unloading. It can reduce the investment in a floating facility and ensure the safety of crude oil production, storage, and external transportation, so as to better meet the development needs of deep-water isolated oil fields and realize the economic development of deep-water isolated oil fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. Throughout the drawings, the same reference numerals are used to denote the same components. In the drawings: Figure 1 It is a structural schematic diagram of a cylindrical FPSO suitable for a dry tree oil production system provided by one embodiment of the present invention.

[0016] 1-hull; 2-upper module; 3-mooring cable; 4-external transmission station; 5-tensioned riser; 6-heave body; 7-conical transition section; 8-cylindrical shell; 9-outboard structure; 10-main deck; 11-moon pool; 12-damping plate. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0018] The present invention provides a design method for a cylindrical FPSO suitable for a dry-tree oil production system, comprising the following steps: hull design; primary dimensions design; production moonpool system design; motion performance design; positioning system design; and compartment design. This method can be used to guide the design of a dry-tree cylindrical FPSO capable of drilling, production, storage, and unloading. This method can reduce the investment required for a single floating facility, ensure safety during crude oil production, storage, and transportation, and better meet the development needs of isolated deepwater oilfields, achieving economical development of these fields.

[0019] Hereinafter, a cylindrical FPSO design method and device applicable to a dry tree oil production system provided by an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0020] Example 1: The present invention proposes a cylindrical FPSO design method suitable for a dry tree oil production system, which specifically includes the following steps: S100. Hull design; S200. Main scale design; S300. Oil production moon pool system design; S400.Sports performance design; S500. Positioning system design; S600. Compartment design. In the above embodiment, preferably, please refer to Figure 1 The designed hull 1 includes a heave body 6, a frustoconical transition section 7, a cylindrical barrel 8 and an outboard structure 9 connected in sequence from bottom to top. A main deck 10 is provided on the top of the outboard structure 9. An upper module 2 for oil and gas production and crude oil storage and an outboard station 4 for crude oil export are provided on the main deck 10.

[0021] In the above embodiment, preferably, the following sub-steps are included when performing the main scale design: S201. Determine development requirements and related parameters: According to the target oilfield development requirements, determine the weight of the upper block 2 and the number of development wells, and determine the size of the moon pool 11; S202 determines the main deck height: according to the target oil field environmental conditions, determine the main deck 10 from the water surface height; S203 determines the diameter of the heaving body: Determine the diameter of the heaving body 6 according to the width of the dock; S204. Determine other dimensions: Set the hull draft 1, the height of the heave body 6, the height of the truncated cone transition section 7, the height of the cylindrical body 8, the width of the damping plate 12 and the height of the outer floating structure 9; S205. Determine the main scale: set the diameter of the cylindrical cylinder 8; S206. Preliminary Stability Calculation: Based on experience, select the weight of Hull 1 structure and, using the ship statics stability calculation method, preliminarily calculate the hull stability under in-position and towing conditions. The in-position stability should not be less than 5m, and the towing assembly draft should not be greater than 9m. The corresponding stability should meet the requirements of relevant regulations. S207. Stability Optimization: Adjust the dimensions of various components of Hull 1 and recalculate the hull stability under in-place and towing conditions. S208. Motion performance calculation: Calculate the natural period of motion of a cylindrical FPSO using the method for calculating the natural period of motion of a rigid body in rigid body dynamics. The natural period of heave should not be less than 22 seconds, and the natural period of pitch and roll should not be more than 40 seconds. S209. Iterative optimization: Iterate steps S201 to S208 to determine the main scale design scheme of the cylindrical FPSO suitable for the dry tree oil production system.

[0022] In the above embodiment, preferably, when designing the oil production moonpool system, a moonpool 11 is provided in the truncated cone transition section 7 and the cylindrical barrel 8, which is connected vertically and serves as a passage for the tensioned riser 5. The tensioned riser 5 is deployed in the moonpool 11 and connected to the dry oil production system in the upper module 2 and the subsea wellhead. The cross-section of the moonpool 11 is set according to the requirements of the tensioned riser 5. At the same time, in order to avoid interference between the tensioned riser 5 and the hull 1, the moonpool 11 can be set in a downward trumpet shape.

[0023] In the above embodiment, preferably, when designing the motion performance, a plurality of damping plates 12 are provided at intervals along the circumferential direction on the outer side of the cylindrical body 8 to improve the motion performance of the hull and ensure long-term safe production.

[0024] In the above embodiment, preferably, when designing the positioning system, an anchoring device is arranged outside the cylindrical barrel 8 to position the hull 1. The anchoring device can be composed of multiple mooring cables 3, and the specific configuration can be determined according to the requirements of trunk tree development.

[0025] In the above embodiment, preferably, when designing the compartments, oil storage tanks and ballast tanks are provided in the truncated cone-shaped transition section 7 and the cylindrical barrel 8, which are vertically connected and distributed along the circumference. The ballast tanks are arranged on the outside of the oil storage tanks. The volumes of the ballast tanks and the oil storage tanks are optimized. Then, a specially designed loading computer is used to pre-calculate and adjust the ballast water to ensure that the storage and output of crude oil and the overall draft of the platform remain constant throughout the service life.

[0026] Example 2: The above-mentioned embodiment 1 provides a cylindrical FPSO design method suitable for a dry tree oil production system. Correspondingly, this embodiment provides a cylindrical FPSO design device suitable for a dry tree oil production system. The cylindrical FPSO design device provided in this embodiment can implement the cylindrical FPSO design method of embodiment 1, and the system can be implemented by software, hardware, or a combination of software and hardware. For example, the system may include integrated or separate functional modules or functional units to execute the corresponding steps in each method of embodiment 1. Since the cylindrical FPSO design device of this embodiment is basically similar to the method embodiment, the process described in this embodiment is relatively simple. For relevant matters, please refer to the partial description of embodiment 1. The cylindrical FPSO design device of this embodiment is merely schematic.

[0027] The cylindrical FPSO design device provided in this embodiment, which is suitable for a dry tree oil production system, comprises: A first processing unit for performing hull design; The second processing unit is used for performing main scale design; The third processing unit is used to design the oil production moon pool system; a fourth processing unit, for performing motion performance design; a fifth processing unit, configured to design a positioning system; The sixth processing unit is used for performing compartment design.

[0028] Example 3: This embodiment provides a processing device for implementing the cylindrical FPSO design method suitable for the dry tree oil production system provided in this embodiment 1. The processing device can be a processing device for a client, such as a mobile phone, laptop computer, tablet computer, desktop computer, etc., to execute the method of embodiment 1.

[0029] The processing device includes a processor, a memory, a communication interface, and a bus. The processor, memory, and communication interface are connected via the bus to facilitate communication between them. The memory stores a computer program executable by the processor. When the processor executes the computer program, it executes the cylindrical FPSO design method provided in Example 1.

[0030] Preferably, the memory may be a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory.

[0031] Preferably, the processor may be a central processing unit (CPU), a digital signal processor (DSP), or other general-purpose processors of various types, which are not limited here.

[0032] Example 4: The cylindrical FPSO design method applicable to the dry tree oil production system of this embodiment 1 can be specifically implemented as a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing the method described in this embodiment 1.

[0033] Computer readable storage media can be tangible devices that hold and store instructions used by instruction execution devices. Computer readable storage media can be, for example, but not limited to, electronic storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any combination thereof.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A cylindrical FPSO design method suitable for a dry tree oil production system, characterized in that: The following steps are involved: hull design; Master scale design; Oil production moon pool system design; sports performance design; Positioning system design; Compartment design.

2. The cylindrical FPSO design method according to claim 1, characterized in that: The designed hull includes a heave body, a frustoconical transition section, a cylindrical barrel and an outboard structure connected in sequence from bottom to top. A main deck is set on the top of the outboard structure. The upper modules for oil and gas production and crude oil storage and the outboard station for crude oil transportation are set on the main deck.

3. The cylindrical FPSO design method according to claim 2, characterized in that: When conducting the main scale design, the following sub-steps are included: Determine development requirements and related parameters: Based on the development requirements of the target oilfield, determine the weight of the upper module and the number of development wellheads, as well as the size of the moon pool; Determine the height of the main deck: Determine the height of the main deck from the water surface based on the environmental conditions of the target oil field; Determine the diameter of the heave body: Determine the diameter of the heave body according to the width of the dock; Determine other dimensions: set the hull draft, heave body height, truncated cone transition section height, cylindrical body height, damping plate width, and flared structure height; Determine the main dimensions: set the diameter of the cylindrical barrel; Preliminary stability calculation: select the hull structure weight based on experience, and use the ship static stability calculation method to preliminarily calculate the hull stability under in-position conditions and towing conditions; Stability optimization: adjust the scale of each hull component and recalculate the hull stability under in-position and towing conditions; Motion performance calculation: Calculate the natural period of motion of cylindrical FPSO based on the calculation method of natural period of rigid body motion in rigid body dynamics; Iterative optimization: Iterate the above steps to determine the main scale design scheme of the cylindrical FPSO suitable for the dry tree oil production system.

4. The cylindrical FPSO design method according to claim 3, characterized in that: When designing the oil production moonpool system, a moonpool that runs vertically through the cone-shaped transition section and the cylindrical barrel is set up as a passage for the tensioned riser. The tensioned riser is deployed in the moonpool and connected to the dry oil production system and the subsea wellhead in the upper module. The moonpool cross-section is set according to the needs of the tensioned riser. At the same time, in order to avoid interference between the tensioned riser and the hull, the moonpool 11 is set to a downward trumpet shape.

5. The cylindrical FPSO design method according to claim 4, characterized in that: When designing the motion performance, a number of damping plates are arranged at intervals along the circumferential direction on the outside of the cylindrical shell to improve the motion performance of the hull and ensure long-term safe production.

6. The cylindrical FPSO design method according to claim 5, characterized in that: When designing the positioning system, an anchoring device is arranged outside the cylindrical shell to position the hull. The anchoring device can be composed of multiple mooring cables.

7. The cylindrical FPSO design method according to claim 6, characterized in that: During the compartment design, oil storage tanks and ballast tanks are set up in the cone-shaped transition section and the cylindrical shell, which are connected vertically and distributed along the circumference. The ballast tanks are arranged on the outside of the oil storage tanks, and the volumes of the ballast tanks and oil storage tanks are optimized. Then, a specially designed loading computer is used to pre-calculate and adjust the ballast water to ensure that the storage and output of crude oil and the overall draft of the platform remain constant throughout the service life.

8. A cylindrical FPSO design suitable for a dry tree oil production system, characterized in that: include: A first processing unit for performing hull design; The second processing unit is used for performing main scale design; The third processing unit is used to design the oil production moon pool system; a fourth processing unit, for performing motion performance design; a fifth processing unit, configured to design a positioning system; The sixth processing unit is used for performing compartment design.

9. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the cylindrical FPSO design method according to any one of claims 1 to 7 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the cylindrical FPSO design method according to any one of claims 1 to 7 are implemented.

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