WO2021219739A1

WO2021219739A1 - Floating offshore hydrocarbon production support facility

Info

Publication number: WO2021219739A1
Application number: PCT/EP2021/061164
Authority: WO
Inventors: Oriol R. Rijken; Todd Vincent Carrico; John CROSS-WHITER; Bruce Martin
Original assignee: Single Buoy Moorings Inc.
Priority date: 2020-04-30
Filing date: 2021-04-28
Publication date: 2021-11-04

Abstract

A floating offshore hydrocarbon production support facility to be located on a body of water and having a first draft at quay site and a second draft at an operational site where it is to be moored to the seabed by a mooring system, the facility including a floating object, a wind turbine and a hydrocarbon production support system including selected process equipment; the wind-turbine including a rotor and a power generator that is coupled to the rotor; the floating object including at least a plurality of buoyancy assemblies, the buoyancy assemblies forming at least three columns extending above the water surface level and the submerged structure interconnecting the at least three columns; each column including one or more compartments for holding an adjustable amount of ballast to achieve desired draft and trim, so as to allow the floating object to float stable and at even keel, at at least two distinctly different drafts.

Description

Floating offshore hydrocarbon production support facility

Field of the invention

The present invention relates to an offshore hydrocarbon production support facility.

Background art

A floating offshore hydrocarbon production support facility is typically used to support offshore hydrocarbon production by a production vessel such as an FPSO (floating production storage and offloading facility) or an FPU during Enhanced Oil Recovery (EOR). EOR is a principle where oil is extracted from a reservoir or well by additional (mechanical) means. EOR increases the amount of oil that can be recovered from a field. EOR can be achieved by means of water injection. EOR comes into play during the later stages of the field. The floating offshore hydrocarbon production support facility provides additional equipment to the production vessel to support the later stage production of hydrocarbons.

Presently, the EOR functionality is added to the existing infrastructure. This can be a challenging proposal as the existing infrastructure may not have the means or capacity to support the EOR activities: there may not be any space available or there is not enough installed power to support the EOR activities.

Summary of the invention

The present invention provides a floating offshore hydrocarbon production support facility to be located on a body of water and having a first draft at quay site and a second draft at an operational site where it is to be moored to the seabed by a mooring system, the facility comprising a floating object, and at least one wind turbine and a hydrocarbon production support system comprising process equipment selected from one or more from a group comprising a supplemental power-to-host facility for providing electric power to a floating hydrocarbon production facility, an FPSO, a gas compression facility for compressing hydrocarbon gases from a subsea well, a supplemental power for a subsea export pipeline booster, and/or power supply facility for Hi-Sep subsea processing; the at least one wind-turbine comprising a rotor and a power generator that is coupled to the rotor; the floating object comprising a plurality of rigidly connected structures both above and below the water surface. There are at least three columns that cross the water line and have a substantial water plane area. The floating object provides sufficient buoyancy to support at least one wind turbine and process equipment. The floating object comprises a plurality of compartments which are used to house ballast so as to adjust the inclination and draft of the vessel.

Accordingly, the floating offshore hydrocarbon production support facility is stable and can intrinsically float at a shallow draft and at a deep draft in a stable manner at even keel, intrinsically meaning without the use of any temporary buoyancy and/or external stability means.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein in one or more columns at least one internal compartment is provided, the internal compartment being configured for holding an adjustable amount of ballast.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein on one or more of the columns at least one external compartment at an external surface of the column is provided, the external compartment being configured for holding an adjustable amount of ballast.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein at least one external compartment is provided within a portion of the submerged structure or at an external surface thereof, the external compartment being configured for holding an adjustable amount of ballast.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, further comprising a top structure that interconnects the at least three columns, wherein the top structure is arranged above water level.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein the top structure is, at least in part, constructed as a truss.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein the submerged structure is, at least in part, constructed as a truss.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein the submerged structure interconnects the at least three columns and consists of pontoons, each pontoon comprising a certain enclosed volume.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein the process equipment is configured to be powered by the at least one wind-turbine and is configured for connection to a hydrocarbon production arrangement on the seabed, wherein the connection to the subsea hydrocarbon production arrangement comprises at least one connection selected from a group comprising: a data transfer line, a power transfer line and a fluid transfer pipe.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, further comprising a fourth column similar to the any one of the first, second and third columns which fourth column is configured with one or more compartments for holding an adjustable amount of ballast.

According to an aspect, the invention relates to an offshore hydrocarbon production support facility as described above, wherein the mooring system comprises an arrangement of mooring lines, each mooring line provided with an in-line mooring connector, ILMC, tensioning connector placed within each mooring line.

Brief description of drawings

The invention will be explained in more detail below with reference to drawings in which illustrative embodiments thereof are shown. The drawings are intended exclusively for illustrative purposes and not as a restriction of the inventive concept which is to cover all modifications, equivalents, and alternatives falling within the scope of the present invention. The scope of the invention is only limited by the definitions presented in the appended claims.

Figure 1 schematically shows a perspective view of an offshore hydrocarbon production support facility in accordance with an embodiment of the invention;

Figure 2 schematically shows a perspective view of an offshore hydrocarbon production support facility in accordance with an embodiment of the invention;

Figure 3 schematically shows a cross-section of a portion of an offshore hydrocarbon production support facility in accordance with an embodiment;

Figure 4 schematically shows a cross-section of a portion of an offshore hydrocarbon production support facility in accordance with an embodiment, and

Figure 5 shows schematically an offshore site above a hydrocarbon reservoir including a floating offshore hydrocarbon production support facility according to an embodiment.

Description of embodiments

The floating offshore hydrocarbon production support facility according to the invention relates to a floating offshore multicolumn structure to be located on a body of water and that supports process equipment which is (partially) powered by one or more onboard wind turbines. Each wind turbine is located on and above column that extends vertically above the water line. The weight of the wind turbine is basically supported by the buoyancy provided by the column underneath; the weight of the equipment is supported by the some of the buoyancy that the other columns provide.

Figure 1 schematically shows a perspective view of an offshore hydrocarbon production support facility in accordance with an embodiment of the invention.

In this embodiment, the floating offshore hydrocarbon production support facility 1 comprises a floating object 10, 11 , 12, 14, 15, a wind turbine 16 and process equipment 17.

The floating object 1 as shown here comprises a plurality of buoyancy assemblies 10,

11 , 12, a top structure 14 and a submerged structure 15. The buoyancy assemblies comprise at least three columns 10, 11 , 12 that, during use, are vertically extending above a water surface level W. The top and submerged structures 14, 15 are horizontally interconnecting the at least three columns.

In an embodiment, the submerged structure 15 interconnects the at least three columns and consists of pontoons, each pontoon comprising a certain enclosed volume which can hold an adjustable amount of ballast. This is explained in more detail with reference to Figure 4.

In an embodiment, the top structure 14 and/or the submerged structure 15 is constructed at least in part as a truss structure.

According to an embodiment each pair of columns is spaced apart over a distance of same order of magnitude.

On the first column 10 of the floating object a wind turbine 16 is mounted.

Further, process equipment 17 is mounted on the second column. Alternatively the process equipment 17 is mounted on the top structure 14 at a position sufficiently remote from the first column not to interfere with the rotor of the wind turbine during operation. Moreover, if an additional wind turbine is mounted on another column, the process equipment is also sufficiently remote from that other column.

The wind turbine 16 can be either a horizontal-axis wind turbine or a vertical-axis wind turbine and comprises at least a rotor and an electric generator (not shown) coupled to the rotor. The electric generator is coupled electrically to the process equipment 17 to supply electric power.

Each of the columns comprises one or more compartments for containing ballast to achieve in cooperation with the compartments in the other columns a desired draft and trim of the floating offshore hydrocarbon production support facility. This will be described in more detail with reference to Figure 3.

For example the compartments in each column are configured to contain an adjustable amount of seawater to obtain the desired draft and trim. The amount of ballast required in each column is also a function of the payload that the respective column is carrying in the form of a wind turbine and/or process equipment.

Figure 2 schematically shows a perspective view of an offshore hydrocarbon production support facility in accordance with an embodiment of the invention.

In Figure 2 entities with the same reference number as shown in Figure 1 refer to corresponding entities.

The floating offshore hydrocarbon production support facility can enlarged to have more than three columns, for example four columns.

According to an embodiment, the floating offshore hydrocarbon production support facility comprises a fourth column 21 which is similar to one of the first, second and third columns 10, 11, 12 and is in a similar manner configured with one or more compartments for containing ballast to achieve a desired draft and trim of the floating offshore hydrocarbon production support facility.

Similar as in the embodiment shown in Figure 1 , the columns 10, 11 , 12, 21 of the floating offshore hydrocarbon production support facility are interconnected by a top structure 14 and a submerged structure 15. On each of the columns either a wind turbine or process equipment can be mounted. Also, as shown in Figure 2, process equipment 17 may be mounted on the interconnecting top structure 14 or a portion thereof.

According to a further embodiment, the floating offshore hydrocarbon production support facility can also be equipped with one or more external compartments (not shown) on one or more of the columns for containing ballast.

Figure 3 schematically shows details of a portion of an offshore hydrocarbon production support facility 1 in accordance with an embodiment. One column 11 of the offshore hydrocarbon production support facility and portions of the submerged structure 15 that interconnects the columns, are shown. For reason of clarity, the top structure 14 is not shown here.

According to the embodiment, within each of the columns, for example column 11 , one or more compartments 24 are provided with a function to hold an adjustable amount of ballast. Accordingly, by adjusting the amount of ballast the compartment(s) 24 can adapt the column's buoyancy and adjust the inclination and draft of the floating offshore hydrocarbon production support facility 1.

It will be appreciated that the one or more compartments 24 can be internal i.e. , located within each column, but additionally or alternatively the compartment(s) 24 may be arranged on an exterior surface of the respective column. Figure 4 schematically shows details of a portion of an offshore hydrocarbon production support facility 1 in accordance with an embodiment. One column of the offshore hydrocarbon production support facility and portions of the submerged structure that interconnects the columns, are shown. For reason of clarity, the top structure 14 is not shown here.

In this embodiment, at least one compartment 25 is provided within a portion of the submerged structure 15 or at an external surface thereof. Accordingly, by adjusting the amount of ballast in the compartment(s) 25, the overall buoyancy of the floating offshore hydrocarbon production support facility 1 can be adapted and the inclination and draft thereof adjusted.

According to an embodiment, the process equipment 17 on the floating offshore hydrocarbon production support facility is configured for connection to a hydrocarbon production arrangement (not shown) on the seabed, wherein the connection to the subsea hydrocarbon production arrangement comprises at least one connection selected from a group comprising: a date transfer line, a power transfer line and a fluid transfer pipe. See Figure 2 which depicts a connecting line or pipe 22.

Alternatively or additionally, the process equipment 17 on the floating offshore hydrocarbon production support facility is configured for connection to a production vessel at an offshore location, wherein the connection to the production vessel comprises at least one connection selected from a group comprising: a date transfer line, a power transfer line and a fluid transfer pipe.

Some or all of the power produced by the wind turbine(s) 16 is used to drive process equipment 17 that is located on the structure of the floating offshore hydrocarbon production support facility 1. The process equipment performs offshore related functions required in and/or around the location of the structure. Examples of such functionality include water injection, C02 injection, pipeline booster, amine facility, hydrogen generation, etc.

The process equipment 17 in combination with one or more wind turbines on the offshore hydrocarbon production support facility can relate to one or more alternative embodiments which can be selected from a group comprising a water injection facility for injecting water into a well, a supplemental power-to-host facility for providing electric power to a floating hydrocarbon production facility (such as an FPSO), a gas compression facility for compressing hydrocarbon gases from a subsea well, a supplemental power for a subsea export pipeline booster, and/or power supply facility for Hi-Sep subsea processing.

According to an embodiment, the process equipment comprises a system for energy storage which is configured to store energy temporarily from the wind turbine(s) and supply the stored energy at suitable time to other equipment requiring power. The other equipment can be located either on the floating offshore hydrocarbon production support facility or at a subsea production plant or on a production vessel.

Each of these facilities can be configured to run in an unmanned set-up.

Figure 5 shows schematically an offshore site above a hydrocarbon reservoir 200 including a floating offshore hydrocarbon production support facility 1 according to an embodiment.

At the offshore site a production vessel 100 such as a floating production and offloading facility FPO(or a floating production storage and offloading facility, FPSO) for hydrocarbons or an FPU i.e., a semi-submersible or a TLP (Tension Leg Platform), is located at sea above a subsea hydrocarbon reservoir. The production vessel 100 may be any type of hydrocarbon production facility that is moored at the location. Any type of mooring system (not shown) such as spread mooring, turret mooring or taut mooring can be used to moor the production vessel. The production vessel is coupled by risers (not shown) to one or more production wells on the seabed from which hydrocarbons are collected.

When the floating offshore hydrocarbon production support facility is at the operational offshore site, the floating object is moored to the seabed by means of a mooring line system 18, 19, 20, with mooring lines attached to each of the at least three columns 10, 11 , 12, 21.

As shown in the drawings, the offshore hydrocarbon production support facility may further comprise a process deck 23A for process equipment, on top of a column not carrying a wind turbine, and/or a process deck 23B for process equipment, running between a pair of the columns.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and have been described in detail. It should be understood that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A floating offshore hydrocarbon production support facility to be located on a body of water and having a first draft at quay site and a second draft at an operational site where it is to be moored to the seabed by a mooring system, the facility comprising a floating object, and at least one wind turbine and a hydrocarbon production support system comprising process equipment selected from one or more from a group comprising a supplemental power-to-host facility for providing electric power to a floating hydrocarbon production facility, an FPSO, a gas compression facility for compressing hydrocarbon gases from a subsea well, a supplemental power for a subsea export pipeline booster, and/or power supply facility for Hi-Sep subsea processing; the at least one wind-turbine comprising a rotor and a power generator that is coupled to the rotor; the floating object comprising at least a plurality of buoyancy assemblies, the buoyancy assemblies forming at least three columns extending above the water surface level and the submerged structure interconnecting the at least three columns; each column comprising one or more compartments for holding an adjustable amount of ballast to achieve desired draft and trim, so as to allow the floating object to float stable and at even keel, at at least two distinctly different drafts.

2. The offshore hydrocarbon production support facility according to claim 1, wherein in one or more columns at least one internal compartment is provided, the internal compartment being configured for holding an adjustable amount of ballast.

3. The offshore hydrocarbon production support facility according to claim 1 or 2, wherein on one or more of the columns at least one external compartment at an external surface of the column is provided, the external compartment being configured for holding an adjustable amount of ballast.

4. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 3, wherein at least one external compartment is provided within a portion of the submerged structure or at an external surface thereof, the external compartment being configured for holding an adjustable amount of ballast.

5. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 4, further comprising a top structure that interconnects the at least three columns, wherein the top structure is arranged above water level.

6. The offshore hydrocarbon production support facility according to claim 5, wherein the top structure is, at least in part, constructed as a truss.

7. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 6, wherein the submerged structure is, at least in part, constructed as a truss.

8. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 7, wherein the submerged structure interconnects the at least three columns and consists of pontoons, each pontoon comprising a certain enclosed volume.

9. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 8, wherein the process equipment is configured to be powered by the at least one wind-turbine and is configured for connection to a hydrocarbon production arrangement on the seabed, wherein the connection to the subsea hydrocarbon production arrangement comprises at least one connection selected from a group comprising: a data transfer line, a power transfer line and a fluid transfer pipe.

10. The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 9, further comprising a fourth column similar to the any one of the first, second and third columns which fourth column is configured with one or more compartments for holding an adjustable amount of ballast.

11 . The offshore hydrocarbon production support facility according to any one of preceding claims 1 - 10, wherein the mooring system comprises an arrangement of mooring lines, each mooring line provided with an in-line mooring connector, ILMC, tensioning connector placed within each mooring line.

12. The offshore hydrocarbon production support facility according to any one of the preceding claims, further comprising a process deck on top of a column not carrying a wind turbine, and/or a process deck running between a pair of columns.