Gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system and method

Abstract

The invention discloses a gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system and method, and belongs to the technical field of oil and gas field multiphase flow metering, the gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system comprises a flow computer, a separation assembly, a fluid inlet pipeline and a fluid outlet pipeline, the separation assembly is communicated with the fluid inlet pipeline, and a liquid level meter and an inlet pressure meter are arranged on the separation assembly; a gas phase pipeline and a liquid phase pipeline which are communicated with the interior of the separation assembly are arranged on the separation assembly, and a liquid level control mechanism is arranged in the separation assembly and used for closing a channel between the separation assembly and the gas phase pipeline when the liquid level in the separation assembly rises; the ends, away from the separation assembly, of the gas-phase pipeline and the liquid-phase pipeline are communicated with the fluid outlet pipeline, a gas-phase flowmeter is arranged on the gas-phase pipeline, and a liquid-phase flowmeter and a liquid path valve are arranged on the liquid-phase pipeline. According to different working conditions, different metering modes can be selected, and metering accuracy is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of multiphase flow metering in oil and gas fields, and in particular relates to a gas-liquid two-phase flow metering system and method with a wide gas-liquid ratio and a wide measuring range. Background Art

[0002] In natural gas development, the production of some high-pressure, high-yield natural gas wells varies greatly, especially the liquid volume fluctuations are particularly large. Conventional non-separation multiphase flowmeters cannot meet the measurement requirements at all. The mature separator metering equipment has large instantaneous flow rates due to large flow fluctuations, which requires large and expensive metering separators. This increases the company's metering and management costs. Therefore, there is an urgent need for a cost-effective metering device that can adapt to the wide measurement range and wide gas-liquid ratio of natural gas wells. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned existing technologies and provide a gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system and method. Different metering modes can be selected according to different working conditions to ensure the accuracy of measurement.

[0004] The technical solution adopted by the present invention is: a gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system, including a flow computer, a separation component, a fluid inlet pipeline and a fluid outlet pipeline, the separation component is connected to the fluid inlet pipeline, the separation component is provided with a liquid level gauge and an inlet pressure gauge, the separation component is provided with a gas phase pipeline and a liquid phase pipeline respectively connected to the interior thereof, the separation component is provided with a liquid level control mechanism, the liquid level control mechanism is used to close the separation component and the gas phase pipeline passage when the liquid level in the separation component rises, the The ends of the gas phase pipeline and the liquid phase pipeline away from the separation component are connected to the fluid outlet pipeline. The gas phase pipeline is provided with a gas phase flowmeter. The liquid phase pipeline is provided with a liquid phase flowmeter and a liquid circuit valve in sequence from the end close to the separation component to the end away from the separation component. The liquid phase pipeline is also provided with a liquid circuit pressure regulating pipeline whose two ends are respectively connected to the liquid phase pipeline and the fluid outlet pipeline. The liquid circuit pressure regulating pipeline is provided with a liquid circuit pressure regulating throttling device. The liquid level meter, inlet pressure gauge, gas phase flowmeter, liquid phase flowmeter and liquid circuit valve are all connected to the flow computer.

[0005] In one embodiment, the separation component includes a pre-separation tube and at least one main separation tube, and the pre-separation tube and at least one main separation tube are connected in sequence through a connecting tube. The inlet pressure gauge is arranged on the pre-separation tube, and the liquid level gauge is arranged on one of the main separation tubes. When there are multiple main separation tubes, a liquid level control mechanism is arranged in at least one main separation tube.

[0006] In one embodiment, the gas phase flowmeter and the liquid phase flowmeter are variable cross-sectional area throttling flowmeters, and a throttling element is provided inside the gas phase flowmeter and the liquid phase flowmeter, and the throttling element blocker is a spindle cone.

[0007] In one embodiment, an air pressure regulating pipeline is provided on the main separation pipe near the fluid outlet pipeline, and the two ends of the air pressure regulating pipeline are respectively connected to the main separation pipe and the gas phase pipeline. An air valve is provided on the air pressure regulating pipeline, and the air valve is connected to the flow computer.

[0008] In one embodiment, the fluid outlet pipeline is provided with a purge pipeline whose two ends are respectively connected to the liquid phase pipeline and the fluid outlet pipeline. The purge pipeline is provided with a purge valve, and the purge valve is connected to the flow computer.

[0009] In one embodiment, an outlet pressure gauge is provided on the fluid outlet pipeline, and the outlet pressure gauge is connected to a flow computer.

[0010] The present invention also discloses a method for measuring a gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range, which is achieved by the gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range measurement system, and comprises the following steps: Step 1: Turn on the system, close the flow computer-controlled liquid valve, set the metering mode switching pressure value and metering mode switching liquid level change rate value, and proceed to step 2; Step 2: The produced medium enters the separation component from the fluid inlet pipeline and is separated into gas phase and liquid phase in the separation component. The gas phase enters the gas phase pipeline and enters step 3. The liquid phase remains in the separation component. The liquid level gauge and the inlet pressure gauge collect the liquid level data and pressure data in the separation component in real time, and output the collected liquid level data and pressure data to the flow computer. The flow computer calculates the liquid level change rate in real time based on the acquired liquid level data. If the collected pressure data and the calculated liquid level change rate do not reach the set metering mode switching pressure value or metering mode switching liquid level change rate value, the system enters the small flow metering mode and enters step 4. If either the collected pressure data or the calculated liquid level change rate reaches the set metering mode switching pressure value and metering mode switching liquid level change rate value, the system enters the large flow metering mode and enters step 9. If the liquid level in the separation component reaches the liquid level at which the liquid level control mechanism opens, the system enters the mechanical liquid level control mode and enters step 11. Step 3: The gas phase passes through the gas flow meter, which measures the gas phase flow in real time and outputs the recorded gas phase flow data to the flow computer. The measured gas phase enters the fluid outlet pipeline and is discharged from the fluid outlet pipeline. Step 4: The flow computer sets the lower limit value and the upper limit value of the measurement liquid level of the separation component, and then proceeds to step 5; Step 5: The liquid phase remaining in the separation component continues to increase. When the liquid phase in the separation component reaches the lower limit of the metering liquid level, the level meter records the metering lower limit differential pressure value and the metering lower limit time, and outputs the recorded metering lower limit differential pressure value and metering lower limit time data to the flow computer. When the liquid phase in the separation component reaches the upper limit of the metering liquid level, the level meter records the metering upper limit differential pressure value and the metering upper limit time, and outputs the recorded metering upper limit differential pressure value and metering upper limit time data to the flow computer, and then proceeds to Step 6. Step 6: Calculate the liquid mass flow rate using the following formula: ,in, is the liquid mass flow rate, is the upper limit differential pressure value of measurement, is the measurement lower limit differential pressure value, is the sum of the cross-sectional areas of the pre-separation tube and at least one main separation tube of the separation assembly, is the acceleration due to gravity, The upper limit time for measurement, To measure the lower limit time, go to step 6; Step 7: The flow computer controls the liquid circuit valve to open, and the liquid phase enters the liquid phase pipeline, enters the fluid outlet pipeline through the liquid phase pipeline, and is discharged from the fluid outlet pipeline; Step 8: The flow computer calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter in step 3 and the liquid phase mass flow rate calculated in step 6; Step 9: The flow computer controls the liquid circuit valve to open, and the liquid phase enters the liquid phase pipeline. The liquid phase passes through the liquid phase flow meter, which measures the liquid phase flow in real time and outputs the recorded liquid phase flow data to the flow computer. The measured liquid phase enters the fluid outlet pipeline and is discharged from the fluid outlet pipeline, and then proceeds to step 10. Step 10: The flow computer calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter in step 3 and the liquid phase flow rate measured in real time by the liquid phase flow meter in step 9; Step 11: The liquid level control mechanism closes the separation component and the gas phase pipeline channel, and the produced medium enters the liquid phase pipeline through the separation component. If the pressure of the produced medium reaches the opening pressure of the liquid pressure regulating and throttling device, the liquid pressure regulating and throttling device is opened, and part of the produced medium enters the liquid pressure regulating pipeline and is discharged from the fluid outlet pipeline. When the liquid level in the separation component reaches the closing condition of the liquid level control mechanism, the liquid level control mechanism opens the separation component and the gas phase pipeline channel, and enters step 2.

[0011] One embodiment further includes a step of adjusting the separation efficiency in a large flow metering mode, specifically as follows: The flow computer adjusts the opening of the liquid circuit valve according to the liquid level data of the separation component obtained, and controls the liquid level in the separation component to be within a stable range.

[0012] In one embodiment, a gas phase pressure adjustment step is further included, which is specifically as follows: Set the abnormal pressure value, and the flow computer obtains the pressure data collected by the inlet pressure gauge in real time. When the obtained pressure data reaches the abnormal pressure value, the flow computer controls the gas circuit valve to open, and part of the gas phase enters the gas circuit pressure regulating pipeline, enters the fluid outlet pipeline after passing through the gas phase pipeline and is discharged from the fluid outlet pipeline. If the obtained pressure data is lower than the abnormal pressure value, the flow computer controls the gas circuit valve to close.

[0013] In one embodiment, a system cleaning step is also included, which is as follows: The cleaning valve is opened manually or controlled by the flow computer, and the metering mode of the metering system controlled by the flow computer stops working. The produced medium enters the separation component through the fluid inlet pipeline to clean the dirt inside the separation component. After cleaning, the cleaning valve is closed manually or controlled by the flow computer, and the metering mode of the metering system controlled by the flow computer starts working, and the system cleaning step is completed.

[0014] The beneficial effects of the present invention are: 1. Different metering modes can be selected according to different working conditions to ensure metering accuracy. For example, if the working conditions are simple, the system can be designed without electric valves to improve the reliability of the device actuator and be maintenance-free. For natural gas wells with complex working conditions and a large range of gas-liquid changes, the device can be designed with electric valves that can automatically adjust the opening of the liquid valve according to relevant information of the working conditions to adapt to working conditions within different gas-liquid ranges, ensure the separation efficiency of the separation components, ensure metering accuracy, and reduce labor costs. 2. The variable cross-sectional area throttling flowmeter has a wider range ratio. The throttling element baffle is designed as a cone, which has a self-cleaning function. It can effectively prevent liquid impurities from accumulating at the front end of the flowmeter and affecting the measurement accuracy, reduce the workload of replacing the throttling element, and reduce the difficulty of using the equipment. 3. Aiming at complex working conditions such as plug flow and intermittent liquid discharge in natural gas wells, the device is equipped with a liquid level control mechanism and a liquid pressure regulating and throttling device to prevent system pressure buildup. It can replace traditional large separators and greatly reduce the metering cost of the oil and gas industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention.

[0016] In the figure: 1. Flow computer; 2. Separation component; 3. Fluid inlet pipeline; 4. Fluid outlet pipeline; 5. Liquid level gauge; 6. Inlet pressure gauge; 7. Gas pipeline; 8. Liquid pipeline; 9. Gas flowmeter; 10. Liquid flowmeter; 11. Liquid circuit valve; 12. Liquid circuit pressure regulating pipeline; 13. Liquid circuit pressure regulating throttling device; 14. Gas circuit pressure regulating pipeline; 15. Gas circuit valve; 16. Purge pipeline; 17. Purge valve; 18. Outlet pressure gauge; 201. Pre-separation pipe; 202. Main separation pipe; 203. Connecting pipe. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] like Figure 1 As shown, the present invention discloses a gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system, comprising a flow computer 1, a separation component 2, a fluid inlet pipeline 3 and a fluid outlet pipeline 4, wherein the separation component 2 is connected to the fluid inlet pipeline 3, the separation component 2 is provided with a liquid level gauge 5 and an inlet pressure gauge 6, the separation component 2 is provided with a gas phase pipeline 7 and a liquid phase pipeline 8 respectively connected to the interior thereof, the separation component 2 is provided with a liquid level control mechanism, the liquid level control mechanism is used to close the passage between the separation component 2 and the gas phase pipeline 7 when the liquid level in the separation component 2 rises, the gas phase pipeline 7 and the liquid phase pipeline 8 are respectively connected to the interior thereof. The end of the pipeline 8 away from the separation component 2 is connected to the fluid outlet pipeline 4, and a gas phase flowmeter 9 is provided on the gas phase pipeline 7. A liquid phase flowmeter 10 and a liquid circuit valve 11 are provided on the liquid phase pipeline 8 from the end close to the separation component 2 to the end away from the separation component 2. The liquid phase pipeline 8 is also provided with a liquid circuit pressure regulating pipeline 12 whose two ends are respectively connected to the liquid phase pipeline 8 and the fluid outlet pipeline 4. A liquid circuit pressure regulating throttling device 13 is provided on the liquid circuit pressure regulating pipeline 12. The liquid level meter 5, inlet pressure gauge 6, gas phase flowmeter 9, liquid phase flowmeter 10 and liquid circuit valve 11 are all connected to the flow computer 1.

[0019] In one embodiment, the separation component 2 includes a pre-separation tube 201 and at least one main separation tube 202, and the pre-separation tube 201 and at least one main separation tube 202 are connected in sequence through a connecting tube 203. The inlet pressure gauge 6 is arranged on the pre-separation tube 201, and the liquid level gauge 5 is arranged on one of the main separation tubes 202. When there are multiple main separation tubes 202, a liquid level control mechanism is arranged in at least one main separation tube 202.

[0020] In this embodiment, the gas phase flowmeter 9 and the liquid phase flowmeter 10 are variable cross-sectional area throttling flowmeters, and throttling components are provided inside the gas phase flowmeter 9 and the liquid phase flowmeter 10, and the throttling component block is a spindle cone.

[0021] In this embodiment, an air pressure regulating pipeline 14 is provided on the main separation pipe 202 near the fluid outlet pipeline 4, and the two ends of the air pressure regulating pipeline 14 are respectively connected to the main separation pipe 202 and the gas phase pipeline 7. An air valve 15 is provided on the air pressure regulating pipeline 14, and the air valve 15 is connected to the flow computer 1.

[0022] In this embodiment, the fluid outlet pipeline 4 is provided with a purge pipeline 16 whose two ends are connected to the liquid phase pipeline 8 and the fluid outlet pipeline 4 respectively. The purge pipeline 16 is provided with a purge valve 17, and the purge valve 17 is connected to the flow computer 1.

[0023] In this embodiment, an outlet pressure gauge 18 is provided on the fluid outlet pipeline 4 , and the outlet pressure gauge 18 is connected to the flow computer 1 .

[0024] The present invention also discloses a method for measuring a gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range, which is achieved by the gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range measurement system, and comprises the following steps: Step 1: Turn on the system, the flow computer 1 controls the liquid circuit valve 11 to close, sets the metering mode switching pressure value and the metering mode switching liquid level change rate value, and proceeds to step 2; Step 2: The produced medium enters the separation component 2 from the fluid inlet pipeline 3 and is separated into a gas phase and a liquid phase in the separation component 2. The gas phase enters the gas phase pipeline 7 and enters step 3. The liquid phase remains in the separation component 2. The liquid level meter 5 and the inlet pressure gauge 6 collect the liquid level data and pressure data in the separation component 2 in real time, and output the collected liquid level data and pressure data to the flow computer 1. The flow computer 1 calculates the liquid level change rate in real time based on the acquired liquid level data. If the collected pressure data and the calculated liquid level change rate do not reach the set metering mode switching pressure value or metering mode switching liquid level change rate value, the system enters the small flow metering mode and enters step 4. If either the collected pressure data or the calculated liquid level change rate reaches the set metering mode switching pressure value or metering mode switching liquid level change rate value, the system enters the large flow metering mode and enters step 9. If the liquid level in the separation component 2 reaches the liquid level at which the liquid level control mechanism is turned on, the system enters the mechanical liquid level control mode and enters step 11. Step 3: The gas phase passes through the gas phase flowmeter 9, which measures the gas phase flow in real time and outputs the recorded gas phase flow data to the flow computer 1. The measured gas phase enters the fluid outlet pipe 4 and is discharged from the fluid outlet pipe 4. Step 4: The flow computer 1 sets the lower limit value and the upper limit value of the metering liquid level of the separation component 2, and then proceeds to step 5; Step 5: The liquid phase remaining in the separation component 2 continues to increase. When the liquid phase in the separation component 2 reaches the lower limit of the metering liquid level, the level meter 5 records the metering lower limit differential pressure value and the metering lower limit time, and outputs the recorded metering lower limit differential pressure value and metering lower limit time data to the flow computer 1. When the liquid phase in the separation component 2 reaches the upper limit of the metering liquid level, the level meter 5 records the metering upper limit differential pressure value and the metering upper limit time, and outputs the recorded metering upper limit differential pressure value and metering upper limit time data to the flow computer 1, and then proceeds to step 6; Step 6: Calculate the liquid mass flow rate using the following formula: ,in, is the liquid mass flow rate, is the upper limit differential pressure value of measurement, is the measurement lower limit differential pressure value, is the sum of the cross-sectional areas of the pre-separation tube and at least one main separation tube of the separation assembly, is the acceleration due to gravity, The upper limit time for measurement, To measure the lower limit time, go to step 6; Step 7: The flow computer 1 controls the liquid circuit valve 11 to open, and the liquid phase enters the liquid phase pipeline 8, enters the fluid outlet pipeline 4 through the liquid phase pipeline 8, and is discharged from the fluid outlet pipeline 4; Step 8: The flow computer 1 calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter 9 in step 3 and the liquid phase mass flow rate calculated in step 6; Step 9: The flow computer 1 controls the liquid circuit valve 11 to open, and the liquid phase enters the liquid phase pipeline 8. The liquid phase passes through the liquid phase flow meter 10, which measures the liquid phase flow in real time and outputs the recorded liquid phase flow data to the flow computer 1. The measured liquid phase enters the fluid outlet pipeline 4 and is discharged from the fluid outlet pipeline 4, and then proceeds to step 10. Step 10: The flow computer 1 calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter 9 in step 3 and the liquid phase flow rate measured in real time by the liquid phase flow meter 10 in step 9; Step 11: The liquid level control mechanism closes the channel between the separation component 2 and the gas phase pipeline 7. The produced medium enters the liquid phase pipeline 8 through the separation component 2. If the pressure of the produced medium reaches the opening pressure of the liquid circuit pressure regulating and throttling device 13, the liquid circuit pressure regulating and throttling device 13 is opened, and part of the produced medium enters the liquid circuit pressure regulating pipeline 12 and is discharged from the fluid outlet pipeline 4. When the liquid level in the separation component 2 reaches the closing condition of the liquid level control mechanism, the liquid level control mechanism opens the channel between the separation component 2 and the gas phase pipeline 7 and enters step 2.

[0025] This embodiment also includes a large flow metering mode separation efficiency adjustment step, which is as follows: The flow calculation machine 1 adjusts the opening of the liquid circuit valve 11 according to the obtained liquid level data of the separation component, and controls the liquid level in the separation component 2 to be in a stable range.

[0026] This embodiment also includes a gas phase pressure adjustment step, which is specifically as follows: An abnormal pressure value is set, and the flow computer 1 obtains the pressure data collected by the inlet pressure gauge 6 in real time. When the obtained pressure data reaches the abnormal pressure value, the flow computer 1 controls the gas circuit valve 15 to open, and part of the gas phase enters the gas circuit pressure regulating pipeline 14, passes through the gas phase pipeline 7, enters the fluid outlet pipeline 4 and is discharged from the fluid outlet pipeline 4. If the obtained pressure data is lower than the abnormal pressure value, the flow computer 1 controls the gas circuit valve 15 to close.

[0027] In this embodiment, the system cleaning step is also included, which is as follows: The purge valve 17 is opened manually or the flow computer 1 controls the purge valve 17 to open, the flow computer 1 controls the metering system metering mode to stop working, the extracted medium enters through the fluid inlet pipe 3, enters the separation component 2, and cleans the dirt inside the separation component 2. After cleaning is completed, the purge valve 17 is closed manually or the flow computer 1 controls the purge valve 17 to close, the flow computer 1 controls the metering system metering mode to start working, and the system purge step is completed.

[0028] In this system, the separation component 2 is separated by vortex flow. The liquid level gauge 5 is a differential pressure liquid level gauge. The liquid level control mechanism is a mechanism or device such as a float valve that can automatically close the gas phase pipeline 7 according to the rise in liquid level. The gas phase flowmeter 9 and the liquid phase flowmeter 10 are variable cross-sectional area throttling flowmeters, and the variable cross-sectional area throttling flowmeter has a wider range ratio; at the same time, its throttling component baffle is designed as a spindle cone, which has a self-cleaning function and can effectively avoid the accumulation of liquid phase impurities at the front end of the flowmeter to affect the measurement accuracy. The liquid circuit pressure regulating and throttling device 13 is a self-closing pressure regulating valve or other device or mechanism that can automatically open when the liquid phase pressure is too high. The setting of the outlet pressure gauge 18 can monitor the pressure value of the system outlet in real time, which is convenient for the system to accurately judge the working condition.

[0029] In this system, the gas flowmeter 9, liquid flowmeter 10, and liquid pressure regulating and throttling device 13 are designed as variable cross-sectional area throttling devices. The throttling device baffle is designed as a spindle cone. When the pressure difference between the front and rear ends of the baffle reaches a certain value, the baffle opens. The pressure difference before the baffle opens will affect the flowmeter measurement. Therefore, the center of the baffle of the gas flowmeter 9 and liquid flowmeter 10 is perforated, giving the throttling device an initial opening to avoid this effect. The baffle of the liquid pressure regulating and throttling device 13 is a sealed design. When the production well produces pure gas, it prevents gas leakage from the liquid line from affecting the measurement.

[0030] In this system, the gas flowmeter 9 and liquid flowmeter 10 are designed using the noise-based two-phase flow metering principle. If the seal of the system's fluid pressure regulating and throttling device is damaged, or if the liquid level control mechanism in the separation tube is damaged, metering can be completed at a reduced precision, improving equipment reliability and efficiency.

[0031] In step 2, the rate of change of the liquid level is calculated by flow computer 1 by dividing the change in liquid level by the time it takes for the change to occur. The change in liquid level is detected by level meter 5. During the high-flow metering mode separation efficiency adjustment step, the opening of liquid valve 11 is determined based on operating conditions to maintain the liquid level within separation assembly 2 within a stable range to ensure the separation efficiency of separation assembly 2. During the system cleaning step, separation in separation assembly 2 proceeds normally, but the metering system's metering mode is deactivated to prevent inaccuracies caused by cleaning.

[0032] The above-described embodiments merely represent specific implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system, characterized in that: The condenser valve is connected to the flowmeter by a valve inlet pipe, and the condenser valve is connected to the flowmeter at the bottom of the pipe. The condenser valve is connected to the flowmeter at the bottom of the pipe. The condenser valve is connected to the flowmeter at the bottom of the pipe. The condenser valve is connected to the flowmeter at the bottom of the pipe.

2. A gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system according to claim 1, characterized in that: The separation component includes a pre-separation tube and at least one main separation tube, and the pre-separation tube and at least one main separation tube are connected in sequence through a connecting tube. The inlet pressure gauge is arranged on the pre-separation tube, and the liquid level gauge is arranged on one of the main separation tubes. When there are multiple main separation tubes, a liquid level control mechanism is arranged in at least one main separation tube.

3. The gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system according to claim 1, characterized in that: The gas phase flowmeter and the liquid phase flowmeter are variable cross-sectional area throttling flowmeters, and throttling components are provided inside the gas phase flowmeter and the liquid phase flowmeter, and the throttling component baffle is a spindle cone.

4. A gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system according to claim 1, characterized in that: An air pressure regulating pipeline is provided on the main separation pipe near the fluid outlet pipeline. The two ends of the air pressure regulating pipeline are respectively connected to the main separation pipe and the gas phase pipeline. An air valve is provided on the air pressure regulating pipeline, and the air valve is connected to the flow computer.

5. The gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system according to claim 1, characterized in that: The fluid outlet pipeline is provided with a cleaning pipeline with two ends respectively connected to the liquid phase pipeline and the fluid outlet pipeline. The cleaning pipeline is provided with a cleaning valve, and the cleaning valve is connected to the flow computer.

6. A gas-liquid two-phase flow wide gas-liquid ratio and wide range metering system according to claim 1, characterized in that: An outlet pressure gauge is provided on the fluid outlet pipeline, and the outlet pressure gauge is connected to a flow computer.

7. A method for measuring gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range, characterized in that: It is achieved by the wide gas-liquid ratio and wide range metering system for gas-liquid two-phase flow according to any one of claims 1 to 6, comprising the following steps: wherein is the liquid phase mass flow rate, is the metering upper limit differential pressure value, is the metering lower limit differential pressure value, is the sum of the cross-sectional areas of the pre-separation tube and at least one main separation tube of the separation component, is the gravitational acceleration, is the metering upper limit time, is the metering lower limit time, and proceeds to step 6; Step 1: Turn on the system, close the flow computer-controlled liquid valve, set the metering mode switching pressure value and metering mode switching liquid level change rate value, and proceed to step 2; Step 2: The produced medium enters the separation component from the fluid inlet pipeline and is separated into gas phase and liquid phase in the separation component. The gas phase enters the gas phase pipeline and enters step 3. The liquid phase remains in the separation component. The liquid level gauge and the inlet pressure gauge collect the liquid level data and pressure data in the separation component in real time, and output the collected liquid level data and pressure data to the flow computer. The flow computer calculates the liquid level change rate in real time based on the acquired liquid level data. If the collected pressure data and the calculated liquid level change rate do not reach the set metering mode switching pressure value or metering mode switching liquid level change rate value, the system enters the small flow metering mode and enters step 4. If either the collected pressure data or the calculated liquid level change rate reaches the set metering mode switching pressure value and metering mode switching liquid level change rate value, the system enters the large flow metering mode and enters step 9. If the liquid level in the separation component reaches the liquid level at which the liquid level control mechanism opens, the system enters the mechanical liquid level control mode and enters step 11. Step 3: The gas phase passes through the gas flow meter, which measures the gas phase flow in real time and outputs the recorded gas phase flow data to the flow computer. The measured gas phase enters the fluid outlet pipeline and is discharged from the fluid outlet pipeline. Step 4: The flow computer sets the lower limit value and the upper limit value of the measurement liquid level of the separation component, and then proceeds to step 5; Step 5: The liquid phase remaining in the separation component continues to increase. When the liquid phase in the separation component reaches the lower limit of the metering liquid level, the level meter records the metering lower limit differential pressure value and the metering lower limit time, and outputs the recorded metering lower limit differential pressure value and metering lower limit time data to the flow computer. When the liquid phase in the separation component reaches the upper limit of the metering liquid level, the level meter records the metering upper limit differential pressure value and the metering upper limit time, and outputs the recorded metering upper limit differential pressure value and metering upper limit time data to the flow computer, and then proceeds to Step 6. Step 6: Calculate the liquid mass flow rate using the following formula: ,in, is the liquid mass flow rate, is the upper limit differential pressure value of measurement, is the measurement lower limit differential pressure value, is the sum of the cross-sectional areas of the pre-separation tube and at least one main separation tube of the separation assembly, is the acceleration due to gravity, The upper limit time for measurement, To measure the lower limit time, go to step 6; Step 7: The flow computer controls the liquid circuit valve to open, and the liquid phase enters the liquid phase pipeline, enters the fluid outlet pipeline through the liquid phase pipeline, and is discharged from the fluid outlet pipeline; Step 8: The flow computer calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter in step 3 and the liquid phase mass flow rate calculated in step 6; Step 9: The flow computer controls the liquid circuit valve to open, and the liquid phase enters the liquid phase pipeline. The liquid phase passes through the liquid phase flow meter, which measures the liquid phase flow in real time and outputs the recorded liquid phase flow data to the flow computer. The measured liquid phase enters the fluid outlet pipeline and is discharged from the fluid outlet pipeline, and then proceeds to step 10. Step 10: The flow computer calculates the mixed fluid flow rate, which is the sum of the gas phase flow rate measured in real time by the gas phase flow meter in step 3 and the liquid phase flow rate measured in real time by the liquid phase flow meter in step 9; Step 11: The liquid level control mechanism closes the separation component and the gas phase pipeline channel, and the produced medium enters the liquid phase pipeline through the separation component. If the pressure of the produced medium reaches the opening pressure of the liquid pressure regulating and throttling device, the liquid pressure regulating and throttling device is opened, and part of the produced medium enters the liquid pressure regulating pipeline and is discharged from the fluid outlet pipeline. When the liquid level in the separation component reaches the closing condition of the liquid level control mechanism, the liquid level control mechanism opens the separation component and the gas phase pipeline channel, and enters step 2.

8. The method for measuring a gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range according to claim 1, characterized in that: It also includes the steps for adjusting the separation efficiency of the large flow metering mode, as follows: The flow computer adjusts the opening of the liquid circuit valve according to the liquid level data of the separation component obtained, and controls the liquid level in the separation component to be within a stable range.

9. The method for measuring a gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range according to claim 1, characterized in that: It also includes a gas phase pressure regulation step, as follows: Set the abnormal pressure value, and the flow computer obtains the pressure data collected by the inlet pressure gauge in real time. When the obtained pressure data reaches the abnormal pressure value, the flow computer controls the gas circuit valve to open, and part of the gas phase enters the gas circuit pressure regulating pipeline, enters the fluid outlet pipeline after passing through the gas phase pipeline and is discharged from the fluid outlet pipeline. If the obtained pressure data is lower than the abnormal pressure value, the flow computer controls the gas circuit valve to close.

10. The method for measuring a gas-liquid two-phase flow with a wide gas-liquid ratio and a wide range according to claim 1, characterized in that: It also includes system cleaning steps, as follows: The cleaning valve is opened manually or controlled by the flow computer, and the metering mode of the metering system controlled by the flow computer stops working. The produced medium enters the separation component through the fluid inlet pipeline to clean the dirt inside the separation component. After cleaning, the cleaning valve is closed manually or controlled by the flow computer, and the metering mode of the metering system controlled by the flow computer starts working, and the system cleaning step is completed.

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