Autonomous multiphase boosting system

Abstract

An autonomous multiphase boosting (AMB) system (1) comprising an inlet pipe (30), equipped with a phase determination assembly (20), configured to determine a gas volume fraction and a mass rate of at least one phase in a multiphase inlet flow flowing in the inlet pipe; a multiphase pump (40); a fluid separator (50), configured to receive a multiphase boosted flow outputted by the multiphase pump and to separate a gas phase from a liquid phase of the multiphase booster flow, the liquid phase being outputted by a liquid outlet (53) to form a liquid flow; a return pipe (70), connecting the liquid outlet to the inlet pipe, the return pipe being equipped with at least a return valve (71); and a controller (80), configured to control the return valve based on the gas volume fraction determined by the phase determination assembly.

Description

AUTONOMOUS MULTIPHASE BOOSTING SYSTEMCROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to US Provisional patent application No. 63 / 552327 that was filed on February 12, 2024, which is herein incorporated by reference in its entirety.BACKGROUND

[0002] Fluids such as hydrocarbon are generally found in subterranean formations and are extracted due to the potential economic and industrial benefits. To gain access to these fluids, wells are generally drilled into the subsurface rocks of the subterranean formations, and by using known techniques, these subterranean fluids can then be extracted out for further processing and usage. However, these subterranean fluids extracted may differ from location to location, and operators may want to know certain characteristics of the produced fluids to facilitate efficient and economic exploration and production, to maximize production. One important characteristic that is of importance to an operator would be the flowrate of the produced fluids which may affect the production quantity or time of the produced fluids, and since produced fluids are often multiphase fluids (e.g., those having some combination of water, oil, and gas), these provide operators with a challenge to determine the flowrate of the produced fluids.

[0003] Therefore, in order to overcome the above-mentioned challenges, surface well testing is generally done on the produced fluids, which may provide various useful information about the produced fluids and their reservoirs, such as volumetric flow rates, properties or composition of the produced fluids, and more. Moreover, surface well testing equipment may be temporarily installed at a wellsite and can include a separator that facilitates the separation of the multiphase- produced fluids, such as into gas, water, and oil phases. In some instances, separated hydrocarbons may be burned at the wellsite as part of the testing process, which may undoubtedly bring about detrimental effects to the environment, such as the production of green house gases.

[0004] Therefore, there is a need for a system that reduces the need for burning in order to ensure the producing of these fluids is not detrimental to the environment.SUMMARY

[0005] The present disclosure relates to an autonomous multiphase boosting (AMB) system comprising: an inlet pipe, equipped with a phase determination assembly, configured to determine a gas volume fraction and a mass rate of at least one phase in a multiphase inlet flow flowing in the inlet pipe; a multiphase pump; a fluid separator, configured to receive a multiphase boosted flow outputted by the multiphase pump and to separate a gas phase from a liquid phase of the multiphase booster flow, the liquid phase being outputted by a liquid outlet to form a liquid flow; a return pipe, connecting the liquid outlet to the inlet pipe, the return pipe being equipped with at least a return valve; and a controller, configured to control the return valve based on the gas volume fraction determined by the phase determination assembly.

[0006] In some embodiments, the phase determination assembly comprises a multiphase flow meter configured to determine a mass rate of a gas phase and a mass rate of a liquid phase in the multiphase inlet flow. In some embodiments, the oil phase and the water phase of the liquid phase are measured simultaneously; in other embodiments, the mass rate of the oil phase and the mass rate of the water phase are measured separately.

[0007] In some embodiments, the phase determination assembly comprises an inlet fluid separator configured to separate the inlet multiphase flow into an inlet gas flow and an inlet liquid flow; a gas flow meter configured to measure the mass rate of the inlet gas flow; and a liquid flow meter configured to measure the mass rate of the inlet liquid flow; and wherein the inlet gas flow and liquid gas flow are recombined downstream of the gas flow meter and liquid flow meter. In some embodiments, the oil phase and the water phase are measured simultaneously; in other embodiments, the oil phase and the water phase of the liquid phase are separated and the mass rate of the oil phase and the mass rate of the water phase are measured separately by separate flowmeters in distinct lines.

[0008] In some embodiments, the gas flow meter and / or the liquid flow meter is a Coriolis meter.

[0009] In some embodiments, the inlet pipe is equipped with at least a pressure and / or a temperature sensor, downstream of the phase determination assembly.

[0010] In some embodiments, the multiphase pump is intended to work within a gas volume fraction envelope based on a desired regulation mode; and the controller is configured to control the return valve so as to self-regulate an amount of liquid needed for the multiphase pump to work in the gas volume fraction envelope based on the desired regulation mode.

[0011] In some embodiments, the liquid separator is configured to work at a pressure lower than 200 bar (-3000 psi), optionally lower than 100 bar (-1500 psi).

[0012] In some embodiments, the liquid separator is a scrubber.

[0013] In some embodiments, the liquid separator comprises a liquid buffer, which volume is greater than 10 1, optionally greater than 20 1 configured to store the liquid phase before being outputted through the liquid output.

[0014] In some embodiments, the fluid separator is configured to output the gas phase through a gas outlet to form an outlet flow; and the fluid separator is configured to output a liquid overflow through the gas outlet when the buffer is full.

[0015] In some embodiments, the gas outlet is connected to a pipeline, a burner, a vent or an underground reinjection assembly.

[0016] In some embodiments, the gas outlet is connected to a carbon dioxide underground sequestration assembly. In such a case, the CO2 can be mixed with water before sequestration.

[0017] In some embodiments, the return pipe is equipped with a flow meter configured to measure the mass rate of a return flow flowing in the return pipe.

[0018] In some embodiments, the return pipe is equipped with a first return valve and a second return valve, the first return valve being a choke valve and the second return valve being a control valve which actuation velocity is greater than an actuation velocity of the first valve.

[0019] In some embodiments, the multiphase pump comprises several pump units, connected in series and / or in parallel.

[0020] In some embodiments, the controller is configured to control the return valve based on a pump state information provided by the multiphase pump.

[0021] The present disclosure also related to a method for controlling a multiphase-produced fluid, comprising liquid and gas, utilizing an autonomous multiphase boosting system, comprising: self-regulating an amount of liquid needed for a multiphase pump to work in a gas volume fraction envelope based on a desired regulation mode; maintaining a gas / liquid ratio by re-injecting the self-regulated amount of liquid; pumping out the self-regulated amount of liquid with the gas and capturing it in a fluid separator or a scrubber; and retaining the self-regulated amount of liquid in the fluid separator to supply the closed loop in liquid.

[0022] The present disclosure also relates to a system for controlling a multiphase-produced fluid, comprising liquid and gas, utilizing an autonomous multiphase boosting system, the system comprising: a processor; memory accessible to the processor; processor-executable instructions stored in the memory and executable by the processor to instruct the system to: self-regulating an amount of liquid needed for a multiphase pump to work in a gas volume fraction envelope based on a desired regulation mode; maintaining a gas / liquid ratio by re-injecting the self-regulated amount of liquid; pumping out the self-regulated amount of liquid with the gas and capturing it in a fluid separator or a scrubber; and retaining the self-regulated amount of liquid in the fluid separator to supply the closed loop in liquid.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present disclosure is best understood from the following detailed description when read with the accompanying Figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0024] FIG. l is a diagram showing the different types of sensors and actuators used in the AMB system, according to one or more examples of the disclosure.DETAILED DESCRIPTION

[0025] Illustrative examples of the subject matter claimed below will now be disclosed. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions may be made to achieve the developers’ specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

[0026] Further, as used herein, the article “a” is intended to have its ordinary meaning in the patent arts, namely “one or more.” Herein, the term “about” when applied to a value generally means within the tolerance range of the equipment used to produce the value, or in some examples, means plus or minus 10%, or plus or minus 5%, or plus or minus 1%, unless otherwise expressly specified. Further, herein the term “substantially” as used herein means a majority, or almost all, or all, or an amount with a range of about 51% to about 100%, for example. Moreover, examples herein are intended to be illustrative only and are presented for discussion purposes and not by way of limitation.

[0027] Produced fluids extracted from subterranean formations such as hydrocarbon have huge economic value and are beneficial for industrial growth. However, due to the multiphase characteristics of these produced fluids, separation for further processes such well surface testing may be required. In some instances, during some of these processes, burning of oil or gas may be required which may undoubtedly bring about detrimental effects to the environment, such as the production of greenhouse gases.

[0028] The present invention discloses an autonomous multiphase boosting (AMB) system, which functions to increase the fluid pressure of the produced fluids upon the completion of further processes in order to reinject it in a pipeline or underground. This in turn reduces the need to constantly separate the multiphase-produced liquid for further processing, which may also help to provide various environmental and commercial benefits. Subsequently, the AMB system provides a means of reducing greenhouse gas emissions by reinjecting instead of flaring or venting. Therefore, the AMB systems and equipment’s main objective is to boost the pressure of multiphasic fluid (gases, liquids) while maintaining a Gas Volume Fraction (GVF) within a pump operating envelope but also minimizing liquid volume required by reusing it in a close loop.

[0029] In one embodiment, the AMB system controls the pressure or flowrate of the produced fluid passing through a multiphase pump, operating parameters have setpoints (SP) which the AMB system maintains through a Proportional-Integral-Derivative (PID) controllers, adjusting the valves opening and controlling fluid volumes and ratios (gas / liquid ratio) in real time.

[0030] In one embodiment, the AMB system can self-adjust its settings to maintain optimal processing and operating conditions.

[0031] In one embodiment, the AMB system comprises: a. Proportional-Integral-Derivative Controllers (PID); b. Plurality of sensors; c. Plurality of actuators; d. Plurality of controllers; e. Fluid separator or scrubber; f. Diverters and piping; g. Automation system (PLC, SCAD A); h. Carbon Dioxide Underground Sequestration; i. Neural Network Model; j. Algorithm; and k. Data Acquisition.

[0032] In some embodiment of the present invention, as seen in Figure 1, the AMB system may comprise of a plurality of sensors, whereby the plurality of sensors may be selected from a group consisting of temperature, flow, density, pressure, or a combination thereof. These additional sensors may provide additional measurements which could be used to infer process diagnostics such as hydrate detection and predict operational events in the future or safety risks.

[0033] Particularly, in the embodiment of Fig. 1, the produced multiphase fluid is inputted in the AMB system 1 through an inlet 10.

[0034] Then the produced multiphase fluid flows through a phase determination assembly 20 comprising a fluid separator 21, separating the gas phase from the liquid phase of the multiphase fluid. The gas flow is then directed to a gas line 22 equipped with a flow meter 23 measuring the mass rate of the gas flow; similarly, the liquid flow is directed to a liquid line 24 equipped with a flow meter 25 measuring the mass rate of the liquid flow; then the gas flow and the liquid flow are recombined at 26.

[0035] For instance, each flow meter is a Coriolis meter. In this embodiment, the oil and water phase of the liquid phase are not separated. However, of course, in variants, the fluid separator could separate the gas, oil and water phases into three distinct lines, each equipped with a distinct flowmeter.

[0036] Then the multiphase fluid flows through an inlet line 30 equipped with a pressure sensor 31 and a temperature sensor 32.

[0037] Then the multiphase fluid reaches a multiphase pump 40 and is tuned into a boosted multiphase fluid. This multiphase pump is intended to work in normal condition within a gas volume fraction envelope. In the present case, the upper end of this gas volume fraction envelope is comprised between 70% and 90%, for instance 80%.

[0038] In this embodiment, the pump comprised a single pump unit. However, in variants, the pump could include several pump units, for instance 2, 3 4 or 6 pump units, connected in series and / or in parallel.

[0039] Then the boosted multiphase fluid is inputted into a fluid separator 60 (a scrubber in the present embodiment) which separated the gas phase of the boosted multiphase fluid from its liquid phase. The gas phase is outputted by a gas outlet 51 and forms a gas flow which is outputted from the AMB system 1 through an output line 60, said output line 60 being here equipped with apressure sensor 61 and a temperature sensor 62. Then the gas flow can be directed to a reinjection assembly to reinject the gas flow downhole. For instance, the reinjection assembly can be a carbon dioxide underground sequestration assembly.

[0040] The liquid phase is retained in a buffer 52 at the bottom of the scrubber 50, said buffer 52 being equipped with a liquid outlet 53. The liquid outlet 53 is connected to a return line 70 which reinjects a liquid flow into the inlet line 30. The return line is equipped with a choke valve 71, a flow meter 72 and a control valve 73.

[0041] In this embodiment, the return line 70 reinjects liquid into the inlet line 30 downstream of the phase determination assembly 20. However, in variants, the liquid could be reinjected upstream of the phase determination assembly 20.

[0042] In the event the flow rate in the return line is small enough and the buffer is full, then liquid phase can be outputted with the gas phase through the gas outlet 51.

[0043] The AMB system 1 further comprises a controller 80 which is configured to control the chole valve 71 and the control valve 73 based on the measurements of the flowmeters 23, 25 so as to regulate an amount of liquid needed for the multiphase pump 40 to work in the gas volume fraction envelope based on the desired regulation mode.

[0044] In another embodiment of the present invention, a method for controlling the multiphase- produced fluid utilizing the AMB system is disclosed. The method comprises the steps of1. Self-regulating the amount of liquid needed for the multiphase pump to work in the GVF envelope based on the desired regulation mode;2. Maintaining a gas / liquid ratio by re-injecting the self-regulated amount of the liquid;3. Pumping out the self-regulated amount of liquid with the gas and capturing it in the scrubber;4. Returning the gas (possible including liquid overflow) downstream where the gas needs to be used or reinjected (pipeline, burner, vent or underground); and5. Retaining the self-regulated amount of liquid in the scrubber in order to be a buffer for the closed loop or sending the self-regulated amount of liquid with the gas if the scrubber is full.

[0045] In some embodiment of the present invention the regulation mode is based on a setpoint (SP) or a set of setpoints which needs to be maintained and can be selected from the group consisting of: a. Output Pressure: the system regulates various parameters to deliver the desired output pressure; b. GVF : the system regulates various parameters to deliver the desired output GVF to remain in the pump operating envelop; c. Fluid rate: the system regulates various parameters (pump frequency, liquid volume / rates, etc..) to deliver the optimum rates within the GVF operating envelope on the pump; and d. Other modes available.

[0046] Moreover, the regulation modes stated above are just a few examples of the basic regulation modes but are not limited to, and different process variables can be adjusted depending on the operating mode selected.

[0047] In another embodiment of the present invention, a control is present to ensure that the AMB system operates as required, whereby the control is accomplished by a PLC communicating in 4- 20mA HART with the electric actuator (other protocols are also accepted). Sensors data are either acquired in 4-20mA HART or over the local area network when coming from other devices, such as the downhole pressure gauge.

[0048] Additionally, quality and safety features are built in order to maintain the safety of the personnel, the integrity of the assets and operation.

[0049] Criteria like minimum opening of the choke, opening rate, torque, etc., are monitored to remain within operating specifications.

[0050] Examples in the present disclosure may also be directed to a non-transitory computer- readable medium storing computer-executable instructions and executable by one or more processors of the computer via which the computer-readable medium is accessed. A computer- readable media may be any available media that may be accessed by a computer. By way of example, such computer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other mediumthat may be used to carry or store desired program code in the form of instructions or data structures and that may be accessed by a computer. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.

[0051] Note also that the software implemented aspects of the subject matter claimed below are usually encoded on some form of program storage medium or implemented over some type of transmission medium. The program storage medium is a non-transitory medium and may be magnetic (e.g., a floppy disk or a hard drive) or optical (e g., a compact disk read only memory, or “CD ROM”), and may be read only or random access. Similarly, the transmission medium may be twisted wire pairs, coaxial cable, optical fiber, or some other suitable transmission medium known to the art. The claimed subject matter is not limited by these aspects of any given implementation.

[0052] The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the disclosure. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the systems and methods described herein. The foregoing descriptions of specific examples are presented for purposes of illustration and description. They are not intended to be exhaustive of or to limit this disclosure to the precise forms described. Obviously, many modifications and variations are possible in view of the above teachings. The examples are shown and described in order to best explain the principles of this disclosure and practical applications, to thereby enable others skilled in the art to best utilize this disclosure and various examples with various modifications as are suited to the particular use contemplated. It is intended that the scope of this disclosure be defined by the claims and their equivalents below.

Claims

CLAIMSWhat is claimed is:1 . An autonomous multiphase boosting (AMB) system comprising: an inlet pipe (30), equipped with a phase determination assembly (20), configured to determine a gas volume fraction and a mass rate of at least one phase in a multiphase inlet flow flowing in the inlet pipe; a multiphase pump (40); a fluid separator (50), configured to receive a multiphase boosted flow outputted by the multiphase pump and to separate a gas phase from a liquid phase of the multiphase booster flow, the liquid phase being outputted by a liquid outlet (53) to form a liquid flow; a return pipe (70), connecting the liquid outlet to the inlet pipe, the return pipe being equipped with at least a return valve (71); and a controller (80), configured to control the return valve based on the gas volume fraction determined by the phase determination assembly.

2. The AMB system of claim 1, wherein the phase determination assembly comprises an inlet fluid separator (21) configured to separate the inlet multiphase flow into an inlet gas flow and an inlet liquid flow; a gas flow meter (23) configured to measure the mass rate of the inlet gas flow; and a liquid flow meter (25) configured to measure the mass rate of the inlet liquid flow; and wherein the inlet gas flow and liquid gas flow are recombined downstream of the gas flow meter and liquid flow meter.

3. The AMB system of claim 1, wherein the phase determination assembly comprises a multiphase flow meter configured to determine a mass rate of a gas phase and a mass rate of a liquid phase in the multiphase inlet flow.

4. The AMB system of any one of claims 1 to 3, wherein the gas flow meter and / or the liquid flow meter is a Coriolis meter.

5. The AMB system of any one of claims 1 to 4, wherein the inlet pipe is equipped with at least a pressure (31) and / or a temperature sensor (32), downstream of the phase determination assembly.

6. The AMB system of any one of claims 1 to 5, wherein the multiphase pump is intended to work within a gas volume fraction envelope based on a desired regulation mode; and wherein the controller is configured to control the return valve so as to self-regulate an amount of liquid needed for the multiphase pump to work in the gas volume fraction envelope based on the desired regulation mode.

7. The AMB system of any one claims 1 to 6, wherein the liquid separator is configured to work at a pressure lower than 200 bar.

8. The AMB system of any one of claims 1 to 7, wherein the liquid separator is a scrubber.

9. The AMB system of any one of claims 1 to 8, wherein the liquid separator comprises a liquid buffer (52), configured to store the liquid phase before being outputted through the liquid output.

10. The AMB system of any one of claims 1 to 9, wherein the fluid separator is configured to output the gas phase through a gas outlet (51) to form an outlet flow; and wherein, the fluid separator is configured to output a liquid overflow through the gas outlet when the buffer is full.

11. The AMB system of any one of claims 1 to 10, wherein the return pipe is equipped with a flow meter (72) configured to measure the mass rate of a return flow flowing in the return pipe.

12. The AMB system of any one of claims 1 to 11, wherein the return pipe is equipped with a first return valve (71) and a second return valve (73), the first return valve being a choke valve and the second return valve being a control valve which actuation velocity is greater than an actuation velocity of the first valve.

13. The AMB system of any one of claims 1 to 12, wherein the controller is configured to control the return valve based on a pump state information provided by the multiphase pump.

14. A method for controlling a multiphase-produced fluid, comprising liquid and gas, utilizing an autonomous multiphase boosting system, comprising: self-regulating an amount of liquid needed for a multiphase pump to work in a gas volume fraction envelope based on a desired regulation mode; maintaining a gas / liquid ratio by re-injecting the self-regulated amount of liquid; pumping out the self-regulated amount of liquid with the gas and capturing it in a fluid separator or a scrubber; and retaining the self-regulated amount of liquid in the fluid separator to supply the closed loop in liquid.

15. A system for controlling a multiphase-produced fluid, comprising liquid and gas, utilizing an autonomous multiphase boosting system, the system comprising: a processor; memory accessible to the processor; processor-executable instructions stored in the memory and executable by the processor to instruct the system to: self-regulating an amount of liquid needed for a multiphase pump to work in a gas volume fraction envelope based on a desired regulation mode; maintaining a gas / liquid ratio by re-injecting the self-regulated amount of liquid; pumping out the self-regulated amount of liquid with the gas and capturing it in a fluid separator or a scrubber; and retaining the self-regulated amount of liquid in the fluid separator to supply the closed loop in liquid.

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