Manifold system for oil production without a TPO line and with an SV line, and method for commissioning a choke module

Abstract

The present invention relates to a manifold system for oil production without a TPO line and with an SV line comprising: a crossover module (MXO); five umbilical termination units (MTUs); a hydraulic and chemical injection distribution unit (CDHIQ); four choke modules; header and service branches (SV); gas lift (GL) header and branches; oil production (PO) header and branches. The present invention also relates to a method for commissioning a choke module that involves the following steps and their respective sub-steps: injection and first circulation of diesel; second circulation of diesel; third circulation of diesel; circulation of water; and removal of choke module.

Description

OIL PRODUCTION MANIFOLD SYSTEM WITHOUT A TPO LINE AND WITH AN SV LINE AND COMMISSIONING METHOD FOR A CHOKE MODULE 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 of oil from wells to the FPSO (typically 4 wells, but not limited to this number), subsea production manifolds (SPMs) help optimize production, reduce CAPEX (capital expenditures), 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 running from the manifold to the power plant: oil production line (OP); gas-lift line (GL); oil production test line (TPO); and gas-lift test line (TGL).

[0007] This type of architecture (also called "standard") offers good flexibility for testing, using the TPO and TGL lines to individually test the 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 great difficulties for replacement, leading to the need for a total interruption of equipment production (shutdown of 4 producing wells in typical architectures) for the complete replacement of a choke module, which generates a loss of efficiency due to the production stoppage (lost profit), in addition to the costs of implementing a system with the 4 subsea lines mentioned above.

[0008] 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 production from the well connected to the module to be replaced) through the method described in this document; c- that has a greater number of MEG injection points for hydrate dissociation operations; d- that allows ROV access to the equipment, providing greater flexibility for hydrate dissociation operations, both with local depressurization and with MEG injection via ROV.

[0009] Consequently, the present invention increases the availability and efficiency of the system. In a single application of the invention, the gain is approximately USD 25,000,000.00 (twenty-five million dollars). In a typical project, the estimated gain is approximately USD 100,000,000.00 (one hundred million dollars).

[0010] We found no patent documents in the prior art that address alternatives aimed at: eliminating TPO and TGL lines, replacing them with a single line (LS) connecting the manifold to the FPSO, thus reducing CAPEX by eliminating a pipeline, decreasing the complexity of the subsea arrangement, and reducing the header size 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 an oil production manifold system with only 3 lines (Service, Production and Gas lift, reducing one pipeline compared to the standard architecture) comprising: a crossover module (MXO); five umbilical termination modules (MTU, one for receiving the main umbilical from the UEP, and four others for control distribution to the ANMs); one hydraulic and chemical injection distribution box (CDHIQ); four choke modules containing multiphase meters.

[0012] Furthermore, the present invention also relates to a method for commissioning a choke module that involves the following steps and their respective sub-steps: diesel injection and first circulation; second diesel circulation; third diesel circulation; water circulation; and choke module removal. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will now be described with reference to typical embodiments thereof and with reference to the accompanying drawings, in which:

[0014] Figure 1 is a representation of the prior art four-well oil production manifold system.

[0015] Figure 2 is a representation of the oil production manifold system for four wells according to the present invention.

[0016] Figure 3 is a representation of the choke modules according to the present invention.

[0017] Figure 4 is a representation of the crossover module according to the present invention.

[0018] Figure 5 is a representation of the flows inside the choke module during production, as well as the condition of its valves in normal operation according to the present invention.

[0019] Figure 6 is a representation of the completed stage 1 of commissioning for removal of the choke module according to the present invention (1st diesel circulation).

[0020] Figure 7 is a representation of the completed stage 2 of commissioning for removal of the choke module according to the present invention (2nd diesel circulation).

[0021] Figure 8 is a representation of the completed stage 3 of commissioning for removal of the choke module according to the present invention (3rd diesel circulation).

[0022] Figure 9 is a representation of the completed stage 4 of commissioning for removal of the choke module according to the present invention (water circulation).

[0023] Figure 10 is a representation of the choke module filled with water and ready for replacement according to the present invention, and a locking cap has been installed in place.

[0024] Figure 11 is a representation of one of the wells where the choke module was removed according to the present invention. DETAILED DESCRIPTION OF THE INVENTION SYSTEM ARCHITECTURE

[0025] The present invention proposes a system comprising an oil production manifold without a TPO line and with an SV line. This type of architecture, when compared with the architecture of the prior art equipment, as shown in Figure 1, presents the following advantages: a. Eliminates TPO and TGL lines, replacing them with a service line (LS) connecting the manifold to the UEP, resulting in CAPEX reduction by eliminating a pipeline, as well as decreasing the complexity of the subsea layout; b. Allows the replacement of a choke module without needing to stop all equipment (as occurred in the standard architecture); d. Reduces the number of crossover modules (XO) from 2 (standard architecture) to 1; e. Allows the replacement of the MXO without stopping equipment production (as occurred in the standard architecture).

[0026] 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.

[0027] 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 complexity of the system, it is necessary to use two MXO blocks (MXO1, MXO2), which allow fluid circulation between the headers, enabling hydrate dissociation and commissioning operations.

[0028] As shown in Figure 2, by eliminating the TPO and TGL lines from the system of the present invention, it is possible to reduce the number of headers in the equipment, as well as enabling production testing through the LS, passing through the multiphase flow meter (MPFM) or not, thus making it possible to commission the choke modules of the MSP for replacement without the need to stop all MSP production.

[0029] The system of the present invention is composed of the following structures: a crossover module (MXO); five umbilical termination modules; four choke modules; a service header and branches (SV); a gas-lift header and branches (GL); an oil production header and branches; valves for ROV access for depressurization and MEG injection.

[0030] Furthermore, the system features resident valves (RV) actuated via ROV and hydraulic valves (HV) actuated remotely.

[0031] As can be seen in Figure 3, which illustrates a choke module in one of the wells, the valves at the choke module inlet are VR-GL1, VR-GL2, VR-PO1, VR-PO2, and VR-SV-1, which normally operate open, while valves VR-PO3 and VR-GL3 normally operate closed. Therefore, an ROV is needed to change the status of these valves to perform certain operations.

[0032] 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 modules.

[0033] 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) and internal MQCs for leak testing of the resident valves at the choke module inlets.

[0034] Therefore, to allow the uninterrupted operation of the other wells in the system during the replacement of one of the choke modules, four steps must be followed. The procedure must be carried out through circulation via ANM, according to the choke module that needs to be replaced. In this sense, cleaning procedures are performed with diesel injection and circulation, followed by water circulation, which are conducted to allow the recovery of the choke module.

[0035] It is also worth highlighting that the positioning of the VH-PO1 and VH-GL1 hydraulic valves aims to prevent the circulation of larger volumes of dead oil through the gas-lift choke during cleaning and commissioning operations, which was one of the causes of wear and clogging by particulates in this type of device in prior art approaches.

[0036] Access from the SV line to the GL line via the VR-GL3 valve is important for cleaning the section from VR-GL1 to VH-GL1 without requiring the circulation of large volumes of dead oil through the gas-lift choke. Access from the SV line to the PO line via the VR-PO3 valve allows for the diversion of well production passing through the meter to the SV line. In the UEP, this SV line can be aligned to the test flap. This provides a way to test the MPFM individually. This option was not possible in previous architectures.

[0037] Figure 4 shows a detailed view of the crossover module (MXO), with the nomenclature adopted for the valves and MEG injection points. It can be observed that two resident manual valves were added to the MXO inlet on the PO and GL headers.

[0038] A MEG injection point was considered at the upper generatrix of the MXO (loop) piping, downstream of the XV-01 valve. MQC interfaces for the ROV were added between the valves located at the inlet of the GL and PO headers. The objective is to use these access points to conduct valve leak tests, allowing the removal of the XO module without halting manifold production, as well as serving as depressurization points for hydrate dissociation. COMMISSIONING METHOD

[0039] The operation of the wells and equipment occurs after the commissioning procedure, initiating production for an existing power plant. Figure 5 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 access valves from the SV line to the GL and PO lines (resident valves VR-GL3 and VR-PO3, and hydraulic valves VH-GL2 and VH-PO2) remain closed (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. VH-PO1, VR-PO2, and VR-PO1 valves open; IV. Arrival of the produced fluid at The gas-lift circuit in the well follows the sequence from the gas-lift header to the well annulus: I. Gas passes through the gas-lift header, being directed to each well through the gas-lift branches; II. Gas passes through the open VR-GL1, VR-GL2, and VH-GL1 valves; III. Gas passes through the open W2 and M2 valves in the annulus.

[0041] Now, we will consider the situation where, during normal equipment production, one of the Multiphase Meters stops operating, 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.

[0042] Figures 6 to 9 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 must obviously be done by ANM, according to the Choke Module that needs to be replaced.

[0043] Initially, it is necessary to stop production at the well in question and interrupt the gas lift flow through the well annulus. This procedure will be divided into four stages: stage 1; stage 2; stage 3; and stage 4.

[0044] Step 1 comprises the following operations: I. Via UEP, close valves VH-GL1, M1, and M2, interrupting gas-lift injection and production at the well; II. Via UEP, open valves VH-GL2 and XO; III. Inject diesel through the service header, passing through the open valve VR-SV1 and entering the Choke Module; IV. Circulate diesel through the service line access to the gas-lift line via the open valve VHGL2. The diesel enters the GL line at a point downstream of valve VH-GL1. This is important because it prevents the circulation of large volumes of dead diesel / oil through the gas-lift choke, which could have an orifice clogged by particulates; V. Circulate diesel through the ANM, entering the ANM through the GL line, passing through valves W2, XO, W1, and returning through the production line; VI. Diesel fuel passes through the open VH-PO1, VR-PO2, and VR-PO1 valves and returns through the production header, being carried along with the production from the other three wells in operation; VII. End of Stage 1.

[0045] Stage 2 comprises the following operations: VIII. Via UEP, open PXO and close valves W1, XO, and W2; IX. Circulate diesel through the gas-lift line, PXO, and returning through the PO line; X. With ROV, close valve VR-GL1 and open valve VR-GL-3; XI. Via UEP, open valve VH-GL1 and close VH-GL2; XII. Circulate diesel in the circuit VR-SV1 – VR-GL3 – VR-GL2 – VH-GL1 – PXO – VH-PO1 – VR-PO2 – VR-PO1, being carried by the PO header along with the production from the other wells; XIII. End of Stage 2.

[0046] Step 3 comprises the following operations: XIV. Via UEP, open valve VH-PO2, close valves VH-GL1 and PXO; XV. Circulate diesel in the VR-SV1 – VH-PO2 – VH-PO1 – VR-PO2 – VR-PO1 circuit, being carried by the PO header along with the production from the other wells; XVI. Via ROV, open VR-PO3; XVII. Via UEP, close valve VH-PO2; XVIII. Circulate diesel in the VR-SV1 – VR-PO3 – VR-PO1 circuit, being carried by the PO header along with the production from the other wells; XIX. End of Step 3.

[0047] Step 4 consists of water circulation operations similar to the previous ones, however, without water circulation in the W2 – XO – W1 circuit. The final situation after water circulation should be as shown in Figure 9, with the resident valves VR-GL1, VR-GL2, VR-PO1 and VR-PO2 closed: XX. After the commissioning steps described above, with the module filled with water, a leak test of the resident valves at the module inlets (VR-GL1, VR-GL2, VR-PO1 and VR-PO2) must be performed. This test can be done in two ways: a. Via ROV, through the MQC accesses between the valves (valve VR-GL1 and VR-PO1 will be tested for leakage into the header, and valves VRGL2 and VR-PO2 for leakage out of the manifold). b. Via SV line, pressurizing through valves VR-GL3 and VR-PO3, and monitoring the pressure through the Pressure Transmitters present in the Module. XXI. After the previous test, close valves VR-GL3, VR-PO3, and VR-SV1 via ROV. XXII. The Choke Module is commissioned, filled with water, and ready for recovery, as can be seen in Figure 10.

[0048] After removing the Choke Module, if it is not immediately replaced with a new Module and the boat has to leave the location, it is necessary to install a locking cover to meet a permanent condition, as can be seen in Figure 11.

Claims

CLAIMS 1. Oil production manifold system without a TPO line and with a SV 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; service header and branches (SV); gas-lift header and branches (GL); oil production header and branches (PO); MQCs for ROV access, serving both for depressurization and MEG injection. 2.A system according to claim 1, characterized in that the crossover module comprises valves VR-01, VR-02, VR-03, VR-04, VR-05, XV-01, XV-E01 and XV-E02, wherein: valve VR-01 is responsible for hydraulic isolation between the MXO and the service header; valve VR-02 is responsible for double-barrier hydraulic isolation between the MXO and the gas lift header; valve VR-03 is responsible for double-barrier hydraulic isolation between the MXO and the gas lift header; valve VR-04 is responsible for double-barrier hydraulic isolation between the MXO and the production header; valve VR-05 is responsible for double-barrier hydraulic isolation between the MXO and the production header; valve XV-01 is responsible for allowing circulation between the service header and the production header. The XV-E01 valve is responsible for injecting MEG into the MXO; the XV-E02 valve is responsible for injecting MEG into the MXO.

3. System according to claim 1, characterized in that the umbilical termination modules (MTU) control the distribution of MEG / ethanol from the trunk umbilical to CDHIQ, and from the manifold to the choke modules and ANMs.

4. System according to claim 1, characterized in that the choke module comprises: Header and service branches (SV); Header and gas-lift branches (GL); and Header and oil production branches (PO).

5. System according to claim 1, characterized in that the service branch (SV) of the choke module further comprises: a VR-SV1 valve, a VR-GL3 valve, a VR-PO3 valve, a VH-GL2 valve and a VH-PO2 valve. 6.System according to claim 1, characterized in that the gas-lift (GL) branch of the choke module additionally comprises: a VR-GL1 valve; a VR-GL2 valve; a VH-GL1 valve; a choke; a single-phase meter (SPFM); and three pairs of pressure and temperature transducers.

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

8. System, according to any one of claims 1 to 7, characterized in that the VR type valves are actuated by an ROV and the VH type valves are actuated remotely.

9. Method of commissioning a choke module in a system as defined in any one of claims 1 to 8, characterized in that it comprises the following steps: a) diesel injection and first circulation; b) second diesel circulation; c) third diesel circulation; d) water circulation; e) choke module removal. 10.Method, according to claim 9, characterized in that step a) comprises: via UEP, closing valves VH-GL1 (in the choke module), M1 and M2 (in the ANM), interrupting gas-lift injection and production in the well; via UEP, opening valves VH-GL2 (in the choke module) and XO (in the ANM); injecting diesel through the service header, passing through the open VR-SV1 valve and entering the choke module; circulating diesel through the service line access to the. Gas lift line through the open VHGL2 valve, where diesel enters the GL line at a point downstream of the VH-GL1 valve; circulate diesel through the ANM, entering the ANM through the GL line passing through valves W2, XO, W1 and returning through the production line; pass the diesel through the choke module through the open VH-PO1, VR-PO2 and VR-PO1 valves and return the diesel through the production header, being carried along with the production from the other three wells in operation.

11. Method, according to claim 9, characterized in that step b) comprises: circulating diesel through the gas lift line, PXO (in the ANM) and returning through the PO line; with the ROV, closing valve VR-GL1 and opening valve VR-GL-3; via UEP opening valve VH-GL1 and closing VH-GL2; Diesel circulates in the VR-SV1 – VR-GL3 – VR-GL2 – VH-GL1 – PXO – VH-PO1 – VR-PO2 – VR-PO1 circuit, with the diesel being carried by the PO header along with the production from the other wells. 12.Method, according to claim 9, characterized in that step c) comprises: via UEP opening valve VH-PO2, closing valves VH-GL1 and PXO; circulating diesel in the circuit VR-SV1 – VH-PO2 – VH-PO1 – VR-PO2 – VR-PO1, being carried by the PO header along with the production from the other wells; via ROV opening VR-PO3; via UEP closing valve VH-PO2;.

12. A method according to claim 9, characterized in that step d) comprises: repeating steps b) and c) circulating water instead of diesel; leak testing of the valves located at the module inlets (VR-GL1, VR-GL2, VR-PO1 and VR-PO2); and closing valves VR-GL3, VR-PO3 and VR-SV1 via ROV.

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