POLYVALENT RISER BALCONY

Abstract

The present invention addresses to the design of a Polyvalent Riser Balcony for an FPSO-type floating unit and the sequencing of the functions of the wells interconnected to the SPU in advance, even before the discovery of the field; consequently, without having the definition of the reservoir drainage plan and the subsea layout. The Polyvalent Riser Balcony can be applied to any development design for new offshore fields. The application of the invention will allow the anticipation of the FPSO production design, as well as its construction and assembly, with great value generation for the production development plans.

Claims

1. A POLYVALENT RISER BALCONY, characterized in that it is specified in advance and independently of the subsea layout definition in production systems for an FPSO.

2. THE POLYVALENT RISER BALCONY according to claim 1, characterized in that it is specified in the conceptual design and basic design phase of an FPSO.

3. THE POLYVALENT RISER BALCONY according to claims 1 and 2, characterized in that the upper riser balcony consists of up to 5 cells, plus 2 extra injection wells, each cell containing a fixed combination of wells, the set of cells, including the 2 extra injection wells, occupying up to 52 slots.

4. THE POLYVALENT RISER BALCONY according to claim 3, characterized in that the configuration with 52 slots has flexibility for rigid and flexible risers.

5. THE POLYVALENT RISER BALCONY according to claim 3, characterized in that the upper riser balcony can be designed and pre-defined with a smaller number of cells and slots.

6. THE POLYVALENT RISER BALCONY according to claims 1 and 2, characterized in that three alternative configurations are possible for the lower riser balcony, namely: Type 1—preferred balcony on the port side, Type 2-preferred balcony on the starboard side, and Type 3—central SPU balcony (port side/starboard side).

7. THE POLYVALENT RISER BALCONY according to claims 1 and 2, characterized in that it is able to be applied in any development design of new offshore fields.

8. THE POLYVALENT RISER BALCONY according to claims 1 and 2, characterized in that it makes the design of the FPSO production system independent of the design of the well network and the subsea design.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be described in greater detail below, with reference to the attached figures which, in a schematic and non-limiting way of the inventive scope, represent examples of its embodiment. The figures are:

[0026] FIG. 1, which illustrates a FPSO floating unit, with emphasis on the riser balcony.

[0027] FIG. 2, which illustrates an FPSO-type floating unit, with emphasis on the riser balcony and the arrival of the risers.

[0028] FIG. 3, which illustrates a FPSO-type floating unit, highlighting the upper riser balcony (1).

[0029] FIG. 4, which illustrates a FPSO-type floating unit, highlighting the lower riser balcony (2).

[0030] FIG. 5, which illustrates the Polyvalent Riser Balcony, object of this invention. Its configuration has a fixed sequencing, but with the necessary flexibility for the drainage network. Particularly, the black and white circles represent the interconnections of producing and injecting wells, respectively, also considering 5 flexible interconnections (supports with a dual function that allow both the interconnection of a producing well and an injection well). FIG. 5 also shows a cluster of 5 wells, then called cells, consisting of 2 producing wells+2 injection wells+1 flexible well (producer/injector). In total, the Polyvalent Riser Balcony can accommodate up to 5 cells and 2 extra injection wells. FIG. 5 also identifies the types of risers used in sequencing the polyvalent balcony, which will allow interconnecting both the production and injection risers, as well as other functions necessary for the design: service lines, gas lift manifolds, gas exporting/importing, control umbilicals, power (actuation of pumping or processing systems), ESDV and PRM (Permanent Reservoir Monitoring) control umbilicals. There are represented: PO (PO)-production riser, WG (IG/IA)-gas/water injection riser, PF (PO/IG/IA)-gas/water production/injection riser, WF (SV/IG/IA)-gas lift/gas/water injection riser, SV (SV)-service/gas lift riser, MGL (MSGL)-gas lift manifold riser, STU (UEH) electro-hydraulic control umbilical, POT (UMB POT)-power umbilical, EG (EG/SV/MSGL)-gas exporting/importing/service/gas lift manifold riser, UEG (UEH ESDV/COT)-ESDV umbilical and optical cable, PRM (UEH PRM)-control umbilical/RPM.

[0031] FIG. 6, which illustrates the Polyvalent Riser Balcony, object of this invention, with the upper riser balcony consisting of up to 5 cells (standard unit that is repeated along the length of the balcony), plus 2 extra injection wells, each cell containing a fixed combination of wells, the set of cells, including the 2 extra injection wells, occupying up to 52 slots, with flexibility for rigid and flexible risers. FIG. 6 also shows a predefined sequencing with 10 producing wells+6 WAG Loop (12 injection wells)+5 Flexible (which can be a producing well convertible into an injection well, or a pair of injection wells in a WAG Loop). FIG. 6 further identifies the types of risers used in sequencing the polyvalent balcony, which will allow interconnecting both the production and injection risers, as well as other functions necessary for the design: service lines, gas lift manifolds, gas exporting/importing, control umbilicals, power (actuation of pumping or processing systems), ESDV and PRM (Permanent Reservoir Monitoring) control umbilicals. The following are represented: PO (PO)-production riser, WG (IG/IA)-gas/water injection riser, PF (PO/IG/IA)-gas/water production/injection riser, WF (SV/IG/IA)-gas lift/gas/water injection riser, SV (SV)-service/gas lift riser, MGL (MSGL)-gas lift manifold riser, STU (UEH) electro-hydraulic control umbilical, POT (UMB POT)-power umbilical, EG (EG/SV/MSGL)-gas exporting/importing/service/gas lift manifold riser, UEG (UEH ESDV/COT)-ESDV umbilical and optical cable, PRM (UEH PRM)-control umbilical/RPM.

[0032] FIG. 7, which illustrates a FPSO-type floating unit, with emphasis on the configuration of well functions on the upper riser balcony of the Polyvalent Riser Balcony. Particularly, the green and red symbols represent the interconnections of producing and injecting wells, respectively.

[0033] FIG. 8, which illustrates three alternative configurations for the lower riser balcony, in relation to the preferred arrival side, namely: Type 1—preferred balcony on the port side, in which the largest number of interconnected risers is defined on the port side from azimuths (direction of arrival) of the risers previously defined on the lower balcony, Type 2—preferred balcony on the starboard side, in which the largest number of risers interconnected on the starboard side is defined from azimuths of the risers previously defined on the lower balcony, and Type 3—central SPU balcony (port side/starboard side), in which a balanced distribution of the number of risers for both sides (port side and starboard side) is defined, based on the azimuths of the risers previously defined in the lower balcony.

[0034] FIG. 9, which illustrates the Polyvalent Riser Balcony with alternative lower riser balcony configurations.

[0035] FIG. 10, which illustrates the Polyvalent Riser Balcony with alternative configurations for the lower riser balcony, including the lower balcony entry edge flexibilities.

[0036] FIG. 11, which illustrates the Polyvalent Riser Balcony with the alternative Type 1 configuration for the lower riser balcony, including the lower balcony entry edge flexibilities.

[0037] FIG. 12, which illustrates the Polyvalent Riser Balcony with the alternative Type 2 configuration for the lower riser balcony, including the lower balcony entry edge flexibilities.

[0038] FIG. 13, which illustrates the Polyvalent Riser Balcony with the alternative Type 3 configuration for the lower riser balcony, including the lower balcony entry edge flexibilities.

DETAILED DESCRIPTION OF THE INVENTION

[0039] The present invention addresses to the design of a riser balcony for a floating production unit of the FPSO type and the sequencing in advance of the functions of the wells to be connected, without having the definition of the reservoir drainage plan and the subsea layout. The riser balcony of an FPSO is a support structure, located on the side of the ship, where the lines connecting the wells to the production system located on the deck arrive, as illustrated in FIGS. 1 and 2. The entry sequencing and connection of wells in the riser balcony affects the entire design of production and injection lines in the process plant.

[0040] The Polyvalent Riser Balcony, object of this invention, has as its main attribute to be specified in advance and independently of the subsea layout definition, with sufficient flexibility to efficiently meet numerous well location plans and subsea designs. As a result, it is possible to pre-specify and design the production system even before the deposit is discovered. The possibility of starting the design, construction and assembly of the FPSO independently from the definition of the drainage network and the subsea layout reduces by several months, or even years, the critical path for the start of production in a field, consistently increasing the financial return on production development designs. The polyvalent riser balcony can be applied in any development design of new offshore fields.

[0041] This new approach constitutes a paradigm shift, allowing the design of the arrival arrangement of the risers and their interconnection with the process plant free of the subsea layout design.

[0042] The sequencing of functions of the wells in the upper riser balcony affects and defines the entire surface plant design. The lower riser balcony in turn is only responsible for receiving the flow lines and leading them to the upper balcony and fundamentally depends on the direction of arrival of the wells. Therefore, it has a varied design, depending on the relative position between the FPSO and the field. The upper and lower riser balconies are indicated in FIGS. 3 and 4, respectively.

[0043] In this invention, the upper riser balcony consists of up to 5 cells (a standard unit that is repeated along the length of the balcony), each cell containing a fixed combination of wells. In addition to the set of cells, there are 2 extra injection wells, occupying up to 52 slots in total, with flexibility for rigid and flexible risers, as can be seen in FIGS. 5 to 7. Analyzes carried out (back tests) indicate that the configuration can flexibly meet a wide range of drainage plans.

[0044] Depending on the scope of a design or group of designs, the polyvalent balcony can be designed and predefined with a smaller number of cells and slots.

[0045] In the present invention, three alternative configurations were created for the lower riser balcony, namely: Type 1—preferred balcony on the port side, in which the largest number of risers are defined to be interconnected on the port side from azimuths (direction of arrival) of previously defined risers on the lower balcony, Type 2—preferred balcony on the starboard side, in which the largest number of risers are defined to be interconnected on the starboard side from the azimuths of the risers previously defined on the lower balcony, and Type 3—central SPU balcony (port side/starboard side), in which a balanced distribution of the number of risers is defined for the two sides (port side and starboard side) from the azimuths of the risers previously defined on the lower balcony, as can be seen in FIGS. 8 to 13.

[0046] The validation of this invention was done through retrospective tests (back tests) carried out in fields currently in production.

[0047] In the proposed sequencing for the polyvalent balcony, the use of subsea processing and boosting systems is also allowed, limited to the use of up to 4 electric power umbilicals, in addition to having 2 service lines that may be required by these types of subsea systems.