Oil production manifold system with production and gas lift headers and methods for commissioning a choke module via gas lift line and rov

Abstract

The present invention relates to an oil production manifold system without a TPO line and without a TGL line, comprising: a crossover module (MXO), five umbilical termination modules, a hydraulic distribution and chemical injection unit (CDHIQ), four choke modules containing multiphase and single-phase meters, a gas lift line header and branches (GL), and an oil production line header and branches (PO). In addition, the present invention also relates to a method for commissioning a choke module comprising the following steps: diesel injection and first diesel circulation; second diesel circulation; third diesel circulation; water circulation; and choke module removal. It further relates to methods for commissioning via ROV, which mitigates the need to circulate large volumes of water and diesel, and is performed via circulation with MEG flow.

Description

OIL PRODUCTION MANIFOLD SYSTEM WITH PRODUCTION HEADER AND GAS LIFT AND COMMISSIONING METHODS FOR CHOKE MODULE VIA GAS LIFT LINE AND ROV FIELD OF THE INVENTION

[0001] The present invention falls within the technical field of oil and gas production and transportation, especially in offshore exploration operations.

[0002] More specifically, the invention focuses primarily on a system of subsea equipment used in the oil and gas industry. This system features changes aimed at improving the efficiency, safety, and economy of subsea production operations through strategies such as optimizing equipment architecture, flow control, well monitoring, and commissioning operations for component replacement. BACKGROUND OF THE INVENTION

[0003] Oil production manifold systems are fundamental for managing the extraction and distribution of oil from the well to the stationary production unit (SPU).

[0004] These manifold systems play a crucial role in facilitating efficient and safe operation on offshore oil production platforms. By pooling and controlling the flow from multiple oil wells to the FPSO (typically 4 wells, but not limited to this number), subsea production manifolds (SPMs) help optimize production, reduce CAPEX, minimize downtime, and maximize oil recovery.

[0005] Furthermore, they ensure the integrity of the process by monitoring and regulating pressures and temperatures. of the fluid throughout the entire production process. The effective implementation of these systems not only increases productivity but also reduces operational and environmental risks, thus contributing to the long-term sustainability and profitability of oil exploration operations.

[0006] Current systems generally have four lines leading to the power plant: oil production line (OP); gas-lift line (GL); oil production test line (OPT); and gas-lift test line (GLT).

[0007] Beyond the control umbilical cord, between the equipment and the UEP.

[0008] This type of architecture (also called standard) offers good flexibility for testing, using TPO and TGL lines to individually test wells, verifying what is produced and what is injected into each well. However, in cases of failures in its multiphase metering modules, this type of system presents significant difficulties for replacement, leading to the need for a complete interruption of equipment production (shutdown of 4 producing wells in typical architectures) for the complete replacement of a choke module. This generates a loss of efficiency due to the production stoppage (lost profit), in addition to the costs of implementing a system with the aforementioned subsea lines.

[0009] Thus, the technical problem solved by the present invention consists of providing a system: a- that has a reduced number of lines; b- that allows the replacement of a choke module without interrupting the production of the entire equipment (interruption only of the production of the well connected to the module to be replaced) through one of the methods described in this document; c- that has a greater number of MEG injection points for hydrate dissociation operations; d- that allows access via ROV to the equipment, providing greater flexibility for hydrate dissociation operations, both with local depressurization and with MEG injection via ROV. STATE OF THE ART

[0010] No prior art documents were found that address alternatives aimed at: eliminating the TPO and TGL lines, connecting the manifold to the UEP, resulting in CAPEX reduction by eliminating two pipelines, as well as decreasing the complexity of the subsea arrangement by eliminating two headers on the equipment; the possibility of commissioning the manifold choke modules without interrupting production from other wells; and reducing the number of crossover modules. SUMMARY OF THE INVENTION

[0011] The present invention presents a manifold system for oil production without a TPO line and without a TGL line, comprising: • a crossover module (MXO); • five umbilical termination modules (MTU, one for receiving the main umbilical coming from the UEP, and four others for control distribution to ANMs); • a hydraulic and chemical injection distribution box (CDHIQ); • four choke modules containing multiphase and single-phase meters; • gas-lift (GL) header and branches; • oil production (PO) header and branches;

[0012] Furthermore, the present invention also relates to a method for commissioning a choke module via a gas-lift line, which involves the following steps and their respective sub-steps: diesel injection and circulation; water circulation; and choke module removal.

[0013] Furthermore, it concerns commissioning methods via ROV, which mitigates the need to circulate large volumes of water and diesel, and is carried out via circulation with MEG flow through the MQC accesses. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will now be described with reference to typical embodiments thereof and with reference to the accompanying drawings, in which:

[0015] Figure 1 is a representation of the prior art four-well oil production manifold system.

[0016] Figure 2 is a representation of the oil production manifold system for four wells according to the present invention.

[0017] Figure 3 is a representation of the choke modules according to the present invention.

[0018] Figure 4 is a representation of the flows inside the choke module during production as well as the the condition of its valves in normal operation according to the present invention.

[0019] Figure 5 is a representation of the completed stage 1 of commissioning via gas-lift line for removal of the choke module according to the present invention (first diesel circulation).

[0020] Figure 6 is a representation of the completed stage 2 of commissioning via gas-lift line for removal of the choke module according to the present invention (second diesel circulation).

[0021] Figure 7 is a representation of the completed stage 3 of commissioning via gas-lift line for removal of the choke module according to the present invention (water circulation).

[0022] Figure 8 is a representation of one of the wells where the choke module was removed according to the present invention (module filled with water).

[0023] Figure 9 is a representation of the flows inside the choke module with MEG flow during the first commissioning method via ROV (commissioning of the choke module only).

[0024] Figure 10 is a representation of the choke module filled with MEG and ready for replacement after the first commissioning method via ROV (commissioning of the choke module only).

[0025] Figure 11 is a representation of the completed stage 1 of the second ROV commissioning method for removing the choke module according to the present invention.

[0026] Figure 12 is a representation of the completed stage 2 of the second ROV commissioning method for removing the choke module according to the present invention.

[0027] Figure 13 is a representation of the choke module filled with MEG after the second commissioning method via ROV and ready for replacement according to the present invention. DETAILED DESCRIPTION OF THE INVENTION SYSTEM ARCHITECTURE

[0028] The present invention proposes a system comprising an oil production manifold without a TPO line and without a TGL line. This type of architecture, when compared to the architecture of the prior art equipment, as shown in Figure 1, presents the following advantages: a- the proposed invention eliminates the TPO and TGL lines, resulting in CAPEX reduction by eliminating two pipelines, in addition to decreasing the complexity of the subsea arrangement; b- it allows the replacement of a choke module without the need to stop the entire equipment (a fact that occurred in the standard architecture); d. It reduces the number of crossover modules (XO) from 2 (standard architecture) to 1; e. It allows the replacement of the MXO without stopping production of the equipment with commissioning via ROV (as occurred in the standard architecture); f- It reduces two headers and branches in the equipment; g- Enables exclusive commissioning of the choke module by MEG injection and circulation with the aid of the ROV through the MQC interfaces.

[0029] In addition to the advantages mentioned above, the architecture features valves accessible via ROV, allowing for local depressurization to dissociate hydrates, which also increases operational availability.

[0030] In more detail, Figure 1 illustrates the state-of-the-art system applied to four wells. In this case, four lines are used: PO, GL, TPO, and TGL. Furthermore, considering the system's complexity, the standard architecture requires the use of two MXO blocks (MXO1, MXO2), which allow fluid circulation between the headers, enabling hydrate dissociation and commissioning operations.

[0031] As shown in Figure 2, by eliminating the TPO and TGL lines from the system of the present invention, it is possible to reduce two headers in the equipment.

[0032] The system of the present invention is composed of the following structures: • a crossover module (MXO); • five umbilical termination modules; • four choke modules; • a gas-lift (GL) header and branches; and • an oil production (PO) header and branches; • valves for ROV access for depressurization and MEG injection.

[0033] Furthermore, the system features resident valves (RV) actuated via ROV and hydraulic valves (HV) actuated remotely.

[0034] For example, as can be seen in Figure 3, which illustrates a choke module in one of the wells, the valves located at the choke module inlet VR-GL1, VR-GL2, VR-GL3, VR-GL4, VR-PO1, VR-PO2, VR-PO3, VR-PO4 are normally open. Therefore, an ROV must be activated to change the status of these valves to perform certain operations. Similarly, the hydraulic valves VH-GL1 and VH-PO1 require a command to operate them.

[0035] Furthermore, the present invention also features a MEG / ethanol injection system to inhibit hydrate formation in the equipment, represented by the Umbilical Termination Module (MTU), the Hydraulic and Chemical Injection Distribution Box (CDHIQ), and the jumpers used to connect the MTU to the CDHIQ and to distribute the hydrate inhibitor from the CDHIQ to the choke and ANM modules.

[0036] In this regard, the system also includes MQC (Multi Quick Connector) interfaces between the resident valves (VR), for access by ROV, which can be used for hydrate dissociation (by depressurization), MEG injection, and MQCs for leak testing of the resident valves at the choke module inlets.

[0037] Therefore, to allow the uninterrupted operation of the other wells in the system during the replacement of one of the choke modules, the steps described in this document must be followed. In this regard, cleaning procedures are carried out with diesel injection and circulation, followed by water circulation, which are conducted to allow the recovery of the choke module, or MEG injection via ROV.

[0038] MQC interfaces were added to the valves located at the choke module inlets for ROV access. The objective is to use these accesses to conduct valve leak tests, allowing the choke module to be removed without halting manifold production, preventing hydrate dissociation. Furthermore, these interfaces are also fundamental for MEG injection and circulation via ROV. COMMISSIONING METHOD VIA GAS-LIFT LINE

[0039] The operation of the wells and equipment occurs after the commissioning procedure, initiating production for an existing power plant. Figure 4 shows one of the choke modules, illustrating the flows during normal production of the MSP. It also highlights the status of the module valves and the ANM producing for the module in question, where the valves of the GL and PO branches remain open (initial state).

[0040] The hydrocarbon flow from the well follows this path through the valves: I. DHSV valve open; II. M1 and W1 valves open; III. VR-PO4, VR-PO3, VH-PO1, VR-PO2, and VR-PO1 valves open; IV. Arrival of the produced fluid at the PO header, and direction to the production line and UEP. The gas-lift circuit in the well follows the sequence from the GL header to the well annulus: I. Gas passes through the gas-lift header, being directed to each well by the gas-lift branches; II. Passage through the open VR-GL1, VR-GL2, VH-GL1, VR-GL3, and VR-GL4 valves; III. Gas passes through the open W2 and M2 valves in the ANM.

[0041] Now we will consider the situation where, during normal equipment production, one of the multiphase meters fails, requiring its replacement. One of the major advantages of the proposed MSP architecture is that it eliminates the need to interrupt the entire manifold production process to clean and replace one of the choke modules, depending on the commissioning method selected.

[0042] Figures 5 to 8 again show one of the Choke Modules, presenting the state of the module's valves and the ANM connected to this module as the cleaning procedures with diesel injection and circulation, followed by water circulation, are conducted to allow the recovery of the Choke Module. The following flowcharts represent the steps with diesel injection. Water injection should be done later, following a very similar sequence of steps. The procedure should be performed according to the Choke Module that needs to be replaced.

[0043] Initially, for the commissioning of the Choke Modules for replacement via gas-lift line, it is necessary to stop the gas-lift injection in all producing wells, as this line will be used as a service line. Therefore, the other wells connected to the manifold should produce by flow during this period. The procedure will be divided into four stages: stage a) diesel injection and circulation; stage b) second diesel circulation; stage c) water circulation; and stage d) choke module removal.

[0044] Stage a) Diesel injection and circulation, comprising the following operations: • Via UEP, close valves M1 and M2, interrupting production at the well; • Via UEP, open valve XO; • Inject diesel via UEP through the GL header, passing through the open VR-GL1 – VR-GL2 – VH-GL1 – VR-GL3 – VR-GL4 valves; • Circulate diesel through the ANM, entering through the GL line, passing through the W2, XO, and W1 valves, and returning through the production line; • Diesel passes through the open VR-PO4 – VR-PO3 – VH-PO1 – VR-PO2 – VR-PO1 valves and returns through the production header, being carried along with the production from the other three wells in operation; • End of Step a), completed as shown in Figure 5.

[0045] Stage b), second diesel circulation, comprises the following operations: • Via UEP, open PXO and close valves W1, XO, and W2; • Circulate diesel through the gas-lift line, PXO, and return through the PO line, being carried by the PO header along with the production from the other wells; Stage b) completed, as shown in Figure 6.

[0046] Step c) Water circulation, consists of water circulation operations similar to the previous ones, however, without water circulation in the W2 – XO – W1 circuit, i.e., with the W2 – XO – W1 valves permanently closed. The final situation after water circulation should be as shown in Figure 7, with the resident valves VR-GL1, VR-GL2, VR-PO1 and VR-PO2 closed by ROV. After diesel and water circulation with return via the production header, the Choke Module is filled with water and ready for replacement.

[0047] After the commissioning steps described above, with the module filled with water, it must be A leak test was performed on the valves located at the module inlets (VR-GL1, VR-GL2, VR-PO1, and VR-PO2). This test is conducted via ROV, through the MQC access points between the valves (VR-GL1 and VR-PO1 valves will be tested for leakage into the header, and VR-GL2 and VR-PO2 valves for leakage out of the manifold).

[0048] Once the watertightness has been verified, the commissioned module, filled with water, is ready to be recovered, carrying out step d) choke module removal, which consists of the Choke Module being removed and commissioned, as can be seen in Figure 8.

[0049] After the removal of the Choke Module, if replacement with a new Module is not done immediately and the vessel has to leave the location, it is necessary to install a blocking cover to meet a permanent condition, as can be seen in Figure 8. ROV COMMISSIONING METHOD

[0050] The addition of resident valve pairs and MQC hubs for ROV access between the Choke Module and the MCVs was an alternative to enable equipment commissioning via ROV, mitigating the need to circulate large volumes of diesel and water, and enabling MEG circulation. Therefore, two commissioning methods for the Choke Module via ROV are presented. First commissioning method for the Choke Module via ROV – Exclusive commissioning of the Choke Module.

[0051] By using resident valve assemblies and MQC hubs for ROV access between the Choke Module and the MCVs, it is possible to commission only the Choke Module. to be replaced. Thus, the first commissioning method for the Choke Module via ROV presents the following operation: • Via ROV, close valves VR-GL1, VR-GL4, VR-PO1 and VR-PO4; • Via ROV, inject MEG through the MQC accesses between the resident valves VR-GL1 / VR-GL2 and VR-PO3 / VR-PO4; • The MEG flow through the GL line enters through the MQC access between valves VR-GL1 / VR-GL2, passes through the module to carry the gas in this section, exits through the MQC access between valves VR-GL3 / VR-GL4, being collected at this outlet; • The MEG flow through the module's PO duct enters through the MQC access between valves VR-PO3 / VR-PO4 to carry the oil inside the module, exits through the MQC access between valves VR-PO2 / VR-PO1, as shown in Figure 9; • After injecting MEG through the MQC access points, close valves VR-GL-2, VR-GL3, VR-PO3, and VR-PO2 via ROV; • Perform leak tests on the 4 pairs of resident valves (VR-GL1 / VR-GL2, VR-GL3 / VR-GL4, VR-PO1 / VR-PO2, VR-PO3 / VR-PO4) via ROV through the MQC interfaces between valves;• Using RSV operation, remove the Choke Module with MEG in the pipeline, as shown in Figure 10. Second commissioning method for the Choke Module via ROV;

[0052] Commissioning via ROV can also be carried out with MEG flow circulation exiting the MQC access between the VR-GL1 / VR-GL2 valves to the ANM, passing through the W2 – XO – W1 and PXO circuits, and returning through the production header, carried with the production from the other wells.

[0053] The procedure for the second commissioning method of the Choke Module via ROV is presented in three stages: Stage a) MEG injection and circulation; Stage b) second MEG circulation; and Stage c) removal of the choke module, taking as a starting point the production situation of the Choke Module, as illustrated in Figure 4.

[0054] Step a) MEG injection and circulation, comprising the following operations: • Via UEP, close valves M1 and M2, interrupting production and gas-lift injection; • Via UEP, open valve XO; • Via ROV, close valve VR-GL1; • Via ROV, inject MEG through the MQC access between resident valves VR-GL1 / VR-GL2. The MEG travels the GL line – W2 / XO / W1 – PO line circuit, returning through the production header along with the production from the other wells; End of Step a), as shown in Figure 11.

[0055] Stage b) Second MEG circulation, comprising the following operations: • Via UEP, close valves W2, XO, and W1; • Via UEP, open valve PXO; • Via ROV, inject MEG through the MQC access between resident valves VR-GL1 / VR-GL2. The MEG travels the GL line – PXO line – PO line circuit, returning through the production header along with the production from the other wells; End of Stage b), as shown in Figure 12.

[0056] Step c) Choke module removal, comprising the following operations: • Using an ROV, close the resident valves VR-GL2, VR-PO1 and VR-PO2; • Before proceeding with the module removal, it is necessary to perform a leak test of the resident valves VR-GL1, VR-GL2, VR-PO1 and VR-PO2, through the MQC interfaces; • If the previous test is successful, the commissioned choke module filled with MEG is ready to be recovered, as shown in Figure 13.

Claims

CLAIMS 1. Oil production manifold system without TPO line and without TGL line, characterized in that it comprises: - a crossover module (MXO); - five umbilical termination modules (MTU); - a hydraulic and chemical injection distribution box (CDHIQ); - four choke modules; - gas-lift (GL) header and branches; and - oil production (PO) header and branches; - MQCs for ROV access, serving both for depressurization and MEG injection.

2. System, according to claim 1, characterized in that the main umbilical termination module (MTU) coordinates the distribution of MEG / ethanol from the CDHIQ to the choke modules and ANMs connected to the equipment.

3. System, according to claim 1, characterized in that the choke module comprises: - a gas-lift (GL) branch; - an oil production (PO) branch. 4.System according to claim 1, characterized in that the gas-lift (GL) line of the choke module additionally comprises: - a VR-GL1 valve; - a VR-GL2 valve; - a VR-GL3 valve; - a VR-GL4 valve; - a VH-GL1 valve;. - a choke; - a single-phase meter (SPFM); and three pairs of pressure and temperature transducers.

5. System according to claim 1, characterized in that the oil production line (PO) of the choke module additionally comprises: - a VR-PO1 valve; - a VR-PO2 valve; - a VR-PO3 valve; - a VR-PO4 valve; - a VH-PO1 valve; - a choke; - a multiphase meter (MPFM); and - three pairs of pressure and temperature transducers.

6. System according to any one of claims 1 to 5, characterized in that the VR type valves are actuated by an ROV and the VH type valves are remotely actuated hydraulically. 7.A method for commissioning a choke module via a gas-lift line in a system, as defined in any one of claims 1 to 6, characterized in that it comprises the following steps: a) diesel injection and circulation; b) second diesel circulation; c) water circulation; d) choke module removal.

8. A method according to claim 7, characterized in that step a) comprises: - via UEP, closing valves M1 and M2, interrupting production at the well; - via UEP, open valve XO; - via UEP, inject diesel through the GL header, passing through valves VR-GL1 – VR-GL2 – VH-GL1 – VR-GL3 – VR-GL4 (open); - circulate diesel through the ANM, entering through the GL line, passing through valves W2, XO, W1 and returning through the production line; - circulate the diesel through valves VR-PO4 – VR-PO3 – VH-PO1 – VR-PO2 – VR-PO1 (open) and return the diesel through the production header, being carried along with the production from the other three wells in operation.

9. Method, according to claim 7, characterized in that step b) comprises: - via UEP, open PXO and close valves W1, XO and W2; - circulate diesel through the gas-lift line, PXO and returning through the PO line, being carried through the PO header along with the production from the other wells. 10.A method, according to any one of claims 7 to 9, characterized in that step c) further comprises: - repeating steps a) and b) circulating water instead of diesel, with valves W2 – XO – W1 permanently closed, and - leak testing via ROV through the MQC accesses of the valves located at the module inlets (VR-GL1, VR-GL2, VR-PO1 and VR-PO2) closed; and - step d), which consists of the Choke Module being removed and commissioned.

11. Method of commissioning a choke module via ROV in a system, as defined in any one of the claims. Claims 1 to 6, characterized in that it comprises the following steps: - via ROV, closing valves VR-GL1, VR-GL4, VR-PO1 and VR-PO4; - via ROV, injecting MEG through the MQC accesses between resident valves VR-GL1 / VR-GL2 and VR-PO3 / VR-PO4; - wherein the MEG flow through the GL line enters through the MQC access between valves VR-GL1 / VR-GL2, passes through the module to carry the gas in that section, exits through the MQC access between valves VR-GL3 / VR-GL4, being collected at that outlet; - the MEG flow through the module's PO duct enters through the MQC access between valves VR-PO3 / VR-PO4 to carry the oil inside the module, exits through the MQC access between valves VR-PO2 / VR-PO1; - After injecting MEG through the MQC access points, via ROV, close valves VR-GL-2, VR-GL3, VR-PO3, and VR-PO2; - Perform leak tests on the 4 pairs of resident valves (VR-GL1 / VR-GL2, VR-GL3 / VR-GL4, VR-PO1 / VR-PO2, VR-PO3 / VR-PO4) via ROV through the MQC interfaces between valves;- via RSV operation, remove Choke Module with MEG in the pipeline.

12. Method of commissioning a choke module via ROV in a system, as defined in any of claims 1 to 6, characterized in that it comprises the following steps: - step a) injection and circulation of MEG; - step b) second circulation of MEG; and - step c) removal of choke module.

13. Method according to claim 12, characterized in that step a) further comprises: - via UEP, closing valves M1 and M2, interrupting gas-lift production and injection; - via UEP, opening valve XO; - via ROV, closing valve VR-GL1; - via ROV, injecting MEG through the MQC access between resident valves VR-GL1 / VR-GL2, where the MEG travels the GL line – W2 / XO / W1 – PO line circuit, returning through the production header along with the production from the other wells.

14. Method according to claim 12, characterized in that step b) further comprises: - via UEP, closing valves W2, XO and W1; - via UEP, opening valve PXO; - via ROV, inject MEG through the MQC access between the resident valves VR-GL1 / VR-GL2, where the MEG travels the GL line – PXO – PO line circuit, returning through the production header along with the production from the other wells. 15.A method according to claim 12, characterized in that step c) further comprises: - via ROV, closing the resident valves VR-GL2, VR-PO1 and VR-PO2; - performing the leak test of the resident valves VR-GL1, VR-GL2, VR-PO1 and VR-PO2, through the MQC interfaces; and - finalizing step c) with the removal of the choke module.

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