A three-phase metering system for oil, gas and water in sand-bearing single wells

Abstract

This utility model discloses a three-phase metering system for oil, gas, and water in a sand-bearing single well, comprising a flow computer, a desander, a gas-liquid separator, a water cut measuring pipe, a fluid inlet pipe, a fluid outlet pipe, and a manifold. The fluid inlet pipe is connected to a separation metering pipe, a sampling measuring pipe, and a large-diameter measuring pipe. The end of the separation metering pipe furthest from the fluid inlet pipe is connected to the gas-liquid separator. A second switching valve is installed on the separation metering pipe. A first gas phase pipeline connected to the top of the gas-liquid separator is provided, and a second two-phase flow meter is installed on the first gas phase pipeline. A first liquid phase pipeline connected to the bottom of the gas-liquid separator is provided, and a first two-phase flow meter is installed on the first liquid phase pipeline. This utility model can accurately measure the flow rates of oil, gas, and water in sand-bearing crude oil.

Description

Technical Field

[0001] This utility model belongs to the field of flow measurement, specifically relating to a three-phase metering system for oil, gas and water in sand-bearing single wells. Background Technology

[0002] In the early stages of oilfield development, due to limitations in formation characteristics and extraction technology, the medium produced from a single well often carries a significant amount of sand particles. This phenomenon is particularly pronounced in areas with complex geological structures or poor formation stability. As development progresses into the middle and later stages, although the sand content gradually decreases, accurate metering of the three-phase fluids (oil, gas, and water) remains a challenge. Throughout the entire development cycle, accurately metering the proportions of these three phases is crucial for optimizing development strategies and improving the economic efficiency of the oilfield.

[0003] The presence of sand particles poses the following problems to the metering of three-phase flow of oil, gas, and water:

[0004] 1. The presence of sand particles alters the flow characteristics of fluids, such as flow velocity and viscosity, which directly affects the separation and metering process of oil, gas and water three-phase flow.

[0005] 2. In the early stages of mining, high sand content poses a challenge to the accuracy and stability of metering equipment. In the middle and later stages, although the sand content decreases, high-precision metering technology is still required to ensure accurate measurement of oil, gas and water.

[0006] 3. Sand-laden fluids may cause excessive wear and blockage of metering equipment during long-term operation, requiring frequent maintenance and increasing the operating costs of the oilfield.

[0007] Therefore, developing a three-phase oil-gas-water metering method that can maintain stability throughout the entire extraction cycle, especially in the early stages when the sediment content is high and in the middle and later stages when the sediment content decreases, is of great significance for improving the production efficiency and economic benefits of oil fields. Utility Model Content

[0008] The technical problem to be solved by this utility model is to address the shortcomings of the prior art by providing a three-phase metering system for oil, gas and water in sand-bearing single wells, which can accurately measure the flow rates of oil, gas and water in sand-bearing crude oil.

[0009] The technical solution adopted in this utility model is as follows: a three-phase metering system for oil, gas, and water in a sand-bearing single well, comprising a flow computer, a desander, a gas-liquid separator, a water cut measuring pipe, a fluid inlet pipe, a fluid outlet pipe, and a manifold. The fluid inlet pipe is respectively equipped with a separation metering pipe, a sampling measuring pipe, and a large-diameter measuring pipe connected thereto. The end of the separation metering pipe furthest from the fluid inlet pipe is connected to the gas-liquid separator, and a second switching valve is provided on the separation metering pipe. The top of the gas-liquid separator is equipped with a first gas phase pipeline connected to its interior, and a second two-phase flow meter is provided on the first gas phase pipeline. The bottom of the gas-liquid separator is equipped with a first liquid phase pipeline connected to its interior, and a first two-phase flow meter is provided on the first liquid phase pipeline. The end of the sampling measuring pipe furthest from the fluid inlet pipe is connected to the desander, and a first switching valve is provided on the sampling measuring pipe. The top of the desander is connected to the water cut measuring pipe via a first connecting pipe, and the bottom of the desander... The system includes a sand discharge pipe, a moisture content meter on a moisture content measuring pipe, an electric heating tape wrapped around the outer surface of the moisture content measuring pipe, a second gas phase pipe connected to a first gas phase pipe near the top of the moisture content measuring pipe, a second liquid phase pipe connected to the bottom of the moisture content measuring pipe, a second regulating valve and a mass flow meter sequentially installed on the second liquid phase pipe from the end near the moisture content measuring pipe to the end away from the moisture content measuring pipe, a third switching valve and a large-diameter flow meter respectively installed on the large-diameter measuring pipe, the other ends of the first gas phase pipe, the first liquid phase pipe, the sand discharge pipe, the second liquid phase pipe and the large-diameter measuring pipe are all connected to a manifold, the manifold is connected to a fluid outlet pipe, and the first switching valve, the second switching valve, the third switching valve, the first two-phase flow meter, the second two-phase flow meter, the moisture content meter, the electric heating tape, the second regulating valve, the mass flow meter and the large-diameter flow meter are respectively connected to a flow computer.

[0010] In one embodiment, the fluid inlet pipe is equipped with an inlet pressure gauge.

[0011] In one embodiment, the fluid outlet pipe is equipped with an outlet pressure gauge.

[0012] In one embodiment, a first regulating valve is provided on the first liquid phase pipeline, and the first regulating valve is connected to a flow computer.

[0013] In one embodiment, a capacitive sensor is installed inside the moisture content measuring tube, and the capacitive sensor is connected to a flow computer.

[0014] The beneficial effects of this utility model are: improving the measurement accuracy of sand-containing crude oil throughout the entire mining cycle, and reducing the operating costs of the oil field by reducing equipment wear and maintenance requirements, which is of great significance for improving the efficiency and economic benefits of oil field development. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] In the diagram: 1. Fluid inlet pipe; 2. Sand remover; 3. Gas-liquid separator; 4. Moisture content measuring pipe; 5. First switch valve; 6. Second switch valve; 7. Third switch valve; 8. First two-phase flow meter; 9. Second two-phase flow meter; 10. Mass flow meter; 11. Large-diameter flow meter; 12. Inlet pressure gauge; 13. Outlet pressure gauge; 14. Fluid outlet pipe; 15. First regulating valve; 16. Moisture content meter; 17. Second regulating valve; 18. Flow computer; 19. Manifold; 20. Separation metering pipe; 21. Sampling and measuring pipe; 22. Large-diameter measuring pipe; 23. First gas phase pipeline; 24. First liquid phase pipeline; 25. Sand discharge pipe; 26. Electric heating tape; 27. Second gas phase pipeline; 28. Second liquid phase pipeline; 29. ​​First connecting pipe. Detailed Implementation

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

[0018] like Figure 1As shown, this utility model discloses a three-phase metering system for oil, gas, and water in a sand-bearing single well, including a flow computer 18, a desander 2, a gas-liquid separator 3, a water cut measuring pipe 4, a fluid inlet pipe 1, a fluid outlet pipe 14, and a manifold 19. The fluid inlet pipe 1 is respectively equipped with a separation metering pipe 20, a sampling measuring pipe 21, and a large-diameter measuring pipe 22 connected to it. The end of the separation metering pipe 20 away from the fluid inlet pipe 1 is connected to the gas-liquid separator 3. A second switching valve 6 is provided on the separation metering pipe 20. The top of the gas-liquid separator 3 is equipped with... The gas-liquid separation pipe 3 has a first gas phase pipeline 23 connected to its interior, and a second two-phase flow meter 9 is installed on the first gas phase pipeline 23. The bottom of the gas-liquid separation pipe 3 has a first liquid phase pipeline 24 connected to its interior, and a first two-phase flow meter 8 is installed on the first liquid phase pipeline 24. The end of the sampling and measuring pipe 21 furthest from the fluid inlet pipe 1 is connected to the sand separator 2, and a first switching valve 5 is installed on the sampling and measuring pipe 21. The top of the sand separator 2 is connected to the moisture content measuring pipe 4 via a first connecting pipe 29, and a sand discharge pipe 25 is installed at the bottom of the sand separator 2. The moisture content measuring tube 4 is equipped with a moisture meter 16, and an electric heating tape 26 is wrapped around its outer surface. Near the top of the moisture content measuring tube 4, it is connected to the first gas phase pipeline 23 via a second gas phase pipeline 27. At the bottom of the moisture content measuring tube 4, a second liquid phase pipeline 28 is connected to it. From the end near the moisture content measuring tube 4 to the end away from the moisture content measuring tube 4, a second regulating valve 17 and a mass flow meter 10 are sequentially installed on the second liquid phase pipeline 28. The large-diameter measuring tube 22 is equipped with a third... The switching valve 7 and the large-diameter flow meter 11 are connected to the manifold 19 at the other end of the first gas phase pipeline 23, the first liquid phase pipeline 24, the sand discharge pipe 25, the second liquid phase pipeline 28 and the large-diameter measuring pipe 22. The manifold 19 is connected to the fluid outlet pipe 14. The first switching valve 5, the second switching valve 6, the third switching valve 7, the first two-phase flow meter 8, the second two-phase flow meter 9, the water content meter 16, the electric heating tape 26, the second regulating valve 17, the mass flow meter 10 and the large-diameter flow meter 11 are respectively connected to the flow computer 18.

[0019] In this embodiment, the fluid inlet pipe 1 is equipped with an inlet pressure gauge 12.

[0020] In this embodiment, the fluid outlet pipe 14 is equipped with an outlet pressure gauge 13.

[0021] In this embodiment, a first regulating valve 15 is provided on the first liquid phase pipeline 24, and the first regulating valve 15 is connected to the flow computer 18.

[0022] In this embodiment, a capacitive sensor is provided inside the moisture content measuring tube 4, and the capacitive sensor is connected to the flow computer 18.

[0023] The present invention relates to a three-phase metering system for oil, gas, and water in sand-bearing single wells, which can be used for metering the three phases of oil, gas, and water in sand-bearing single wells. It includes a method for three-phase metering of oil, gas, and water in sand-bearing single wells, the method comprising the following steps:

[0024] Step 1: The mixed fluid enters through fluid inlet pipe 1. If high sediment content multiphase flow metering is to be performed, proceed to step 2. If low sediment content multiphase flow metering is to be performed, proceed to step 3. If low sediment content multiphase flow sampling metering is to be performed, proceed to step 5.

[0025] Step 2: The flow computer 18 controls the first switch valve 5 and the second switch valve 6 to close, and controls the third switch valve 7 to open. The mixed fluid enters the large-diameter measuring pipe 22, passes through the large-diameter flow meter 11 and the manifold 19, and is discharged from the fluid outlet pipe 14. The large-diameter flow meter 11 measures the mixed fluid flow rate in real time and outputs the measured mixed fluid flow rate data to the flow computer 18.

[0026] Step 3: The flow computer 18 controls the first switch valve 5 and the third switch valve 7 to close, and controls the second switch valve 6 to open. The mixed fluid enters the gas-liquid separation pipe 3 through the separation metering pipe 20. The gas-liquid separation pipe 3 works to split the mixed fluid into a gas phase containing a small amount of liquid phase and a liquid phase containing a small amount of gas phase, and then proceeds to step 4.

[0027] Step 4: The gas phase containing a small amount of liquid enters the first gas phase pipeline 23, passes through the second two-phase flow meter 9 and the manifold 19, and is discharged from the fluid outlet pipe 14. The second two-phase flow meter 9 measures the flow rate of the gas phase containing a small amount of liquid in real time and outputs the measured flow rate data of the gas phase containing a small amount of liquid to the flow computer 18. The liquid phase containing a small amount of gas enters the first liquid phase pipeline 24, passes through the first two-phase flow meter 8 and the manifold 19, and is discharged from the fluid outlet pipe 14. The first two-phase flow meter 8 measures the flow rate of the liquid phase containing a small amount of gas in real time and outputs the measured flow rate data of the liquid phase containing a small amount of gas to the flow computer 18.

[0028] Step 5: The flow computer 18 sets the maximum value of the sampling liquid level and the sampling temperature value. The flow computer 18 controls the second switch valve 6, the third switch valve 7 and the second regulating valve 17 to close, and controls the first switch valve 5 to open. The mixed fluid enters the sand remover 2 through the sampling measuring tube 21. The sand remover 2 works to separate the mixed fluid into sand particles and sampling multiphase flow, and then proceeds to step 6.

[0029] Step 6: Sand particles enter the sand discharge pipe 25, are discharged through the manifold 19 and the fluid outlet pipe 14, and the sampled multiphase flow enters the moisture content measuring pipe 4 through the first connecting pipe 29. The moisture meter 16 measures the liquid level in the moisture content measuring pipe 4 in real time and outputs the measured liquid level data to the flow computer 18. When the liquid level in the moisture content measuring pipe 4 reaches the maximum value of the sampling liquid level, the flow computer 18 controls the first switch valve 5 to close and proceeds to step 7.

[0030] Step 7: The small amount of gas remaining in the multiphase flow is sampled and discharged sequentially through the second gas phase pipeline 27, the first gas phase pipeline 23 and the manifold 19 and the fluid outlet pipe 14. The flow computer 18 controls the electric heating tape 26 to work and heat the moisture content measuring tube 4. The moisture meter 16 measures the temperature inside the moisture content measuring tube 4 in real time and outputs the measured temperature data to the flow computer 18. When the temperature inside the moisture content measuring tube 4 reaches the sampling temperature value, the flow computer 18 controls the electric heating tape 26 to turn off and proceeds to step 8.

[0031] Step 8: Let the moisture content measuring tube 4 stand still. The internal temperature of the moisture content measuring tube 4 will naturally decrease, and the water and oil inside the moisture content measuring tube 4 will naturally separate into layers. After standing for a period of time, the flow computer 18 controls the second regulating valve 17 to open. The sampled multiphase flow passes through the second regulating valve 17 and the mass flow meter 10 into the manifold 19 and is discharged from the fluid outlet 14. The mass flow meter 10 measures the sampled multiphase flow data in real time and outputs the measured data to the flow computer 18.

[0032] In this embodiment, after the first switch valve 5 is closed in step 6, the flow computer 18 controls the three-phase metering system for oil, gas and water in sandy single wells to switch to multiphase flow metering with low sand content, and then proceeds to step 3.

[0033] In this embodiment, during step 8, when the second regulating valve 17 is opened, the flow computer 18 controls the flow rate of the multiphase flow in real time by controlling the opening degree of the second regulating valve 17.

[0034] In this embodiment, a pressure loss adjustment step for the gas-liquid separator 3 is also included, as detailed below:

[0035] The flow computer 18 sets a maximum and a minimum liquid level threshold for the gas-liquid separator 3. When the liquid level in the gas-liquid separator 3 reaches the maximum threshold, the flow computer 18 controls the first regulating valve 15 to slowly close, causing the liquid level in the gas-liquid separator 3 to drop back to the normal level. When the liquid level in the gas-liquid separator 3 reaches the minimum threshold, the flow computer 18 controls the first regulating valve 15 to slowly open, causing the liquid level in the gas-liquid separator 3 to return to the normal level.

[0036] This embodiment also includes a moisture content measurement and calibration step, as detailed below:

[0037] The capacitive sensor acquires the capacitance signal of the sampled multiphase flow inside the moisture content measuring tube 4 in real time, and outputs the acquired capacitance signal to the flow computer 18. The flow computer 18 compares the acquired capacitance signal with the sampled multiphase flow data acquired by the mass flow meter 10 and performs calibration based on the comparison data.

[0038] The functions of each component in this metering system are as follows:

[0039] 1. Fluid inlet pipe 1: System inlet, the mixed fluid to be measured enters the system from here.

[0040] 2. Sand separator 2: This is a cyclone separator sand separator 2. When performing sampling and measurement of multiphase flow with low sand content, it can separate sand particles in the mixed fluid to ensure that the water content measurement is not affected.

[0041] 3. Gas-liquid separation tube 3: This is a gas-liquid cyclone separator used for pre-separation of the measured mixed fluid.

[0042] 4. Moisture content measuring tube 4: When sampling and measuring multiphase flow with low sand content, the multiphase flow is intercepted and retained inside the tube for subsequent moisture content measurement.

[0043] 5. First switch valve 5: This is an inlet electric switch valve for low sand content multiphase flow sampling and metering. After it is turned on, the system performs low sand content multiphase flow sampling and metering (the second switch valve 6 and the third switch valve 7 need to be closed).

[0044] 6. Second switch valve 6: This is an inlet electric switch valve for low sand content multiphase flow metering. After it is turned on, the system enters low sand content multiphase flow metering (the first switch valve 5 and the third switch valve 7 need to be closed).

[0045] 7. Third switch valve 7: This is a large-diameter pipeline shut-off valve. After it is turned on, the equipment enters the high sand content multiphase flow metering (the first switch valve 5 and the second switch valve 6 need to be closed).

[0046] 8. First two-phase flow meter 8: Used to measure the flow rate of two phases with a high liquid phase ratio.

[0047] 9. Second Two-Phase Flow Meter 9: Used to measure the flow rate of two phases with a high gas-liquid ratio.

[0048] 10. Mass flow meter 10: Used to sample multiphase flow data and measure instantaneous density and flow rate.

[0049] 11. Large-diameter flow meter: used for metering multiphase flow with high sand content.

[0050] 12. Inlet pressure gauge 12: Displays pressure and, in conjunction with outlet pressure gauge 13, determines whether there is pressure buildup in the system.

[0051] 13. Outlet pressure gauge 13: Displays pressure and, in conjunction with inlet pressure gauge 12, determines whether there is pressure buildup in the system.

[0052] 14. Fluid outlet pipe 14: The measured mixed fluid returns to the production pipeline.

[0053] 15. First regulating valve 15: This is a regulating valve for the first liquid phase pipeline 24, used to control the liquid phase pressure loss and ensure that no excessive gas passes through the first liquid phase pipeline 24.

[0054] 16. Moisture meter 16: This is a capacitive moisture meter 16, used to assist the mass flow meter 10 in measuring moisture content.

[0055] 17. Second regulating valve 17: Used to control the flow rate during sampling and metering of multiphase flow with low sand content.

[0056] 18. Flow computer 18: Composed of PLC, human-machine interface and communication and control modules, it ensures accurate data capture and control of the process.

[0057] 19. Manifold 19: Used for manifolding after metering in various metering modes.

[0058] 20. Separation metering tube 20: used to connect fluid inlet tube 1 and gas-liquid separation tube 3.

[0059] 21. Sampling and measuring tube 21: used to connect fluid inlet tube 1 and sand remover 2.

[0060] 22. Large-diameter measuring pipe 22: Used to connect fluid inlet pipe 1 for metering of multiphase flow with high sand content.

[0061] 23. First gas phase pipeline 23: Used for the passage of gas phase containing a small amount of liquid phase in the metering of multiphase flow with low sand content, so as to perform metering.

[0062] 24. First liquid phase pipeline 24: Used for metering of low sand content multiphase flow, allowing the passage of liquid phase containing a small amount of gas phase for metering.

[0063] 25. Sand discharge pipe 25: Used to discharge the sand separated by the sand separator 2.

[0064] 26. Electric heating tape 26: Used for heating the moisture content measuring tube 4 when sampling and measuring multiphase flow with low sand content.

[0065] 27. Second gas phase pipeline 27: When used for sampling and metering of multiphase flow with low sand content, it is connected to the first gas phase pipeline 23 so that the small amount of gas remaining in the multiphase flow can be sampled and enter the first gas phase pipeline 23.

[0066] 28. Second liquid phase pipeline 28: Used for sampling and metering of multiphase flow with low sand content, through which the sampled multiphase flow passes after heating and settling, so as to facilitate the measurement by mass flow meter 10.

[0067] 29. First connecting pipe 29: used to connect the sand remover 2 and the moisture content measuring pipe 4.

[0068] In this metering method, in step 8, the settling time of the moisture content measuring tube 4 is set by the flow computer 18, and the specific time is set according to the on-site medium conditions and user requirements. In the pressure loss adjustment step of the gas-liquid separation tube 3, the opening and closing of the first regulating valve 15 is controlled by the highest and lowest liquid level thresholds; a dual-flange differential pressure transmitter can be installed on the gas-liquid separation tube 3 to measure the liquid level; the dual-flange differential pressure transmitter acquires the liquid level data and outputs it to the flow computer 18.

[0069] The specific measurement principle of this system is as follows:

[0070] 1. Large-diameter flow meter for high-sediment-content multiphase flow measurement:

[0071] The large-diameter flow meter 11 in this system is a large-diameter variable area flow meter. In this type of flow meter, the core structure is a horizontally positioned baffle, similar to an orifice plate. When fluid flows horizontally, it first impacts the baffle. Initially, the fluid flows through the annular gap between the baffle and the inner wall of the pipe. As the fluid flow rate increases, the impact force on the baffle increases. This impact force, along with the pressure of the fluid at the rear end of the pipe and the baffle's own resistance, acts together. When the flow rate increases to a certain level, and the impact force exceeds the sum of the pressure and resistance at the rear end, the baffle begins to move backward. As the baffle moves backward, the annular cross-sectional area formed between the baffle and the inner wall of the pipe gradually increases. According to the continuity equation in fluid mechanics, to maintain stable fluid flow under increasing flow rate, the flow velocity needs to remain relatively stable, and the increased annular cross-sectional area precisely meets this requirement. In this process, there is a corresponding relationship between the baffle position and the flow rate. By using the model of the correspondence between the baffle position change and the flow rate, the fluid flow rate can be accurately determined.

[0072] In large-diameter pipes, the fluid velocity distribution is relatively uniform, reducing the accumulation of sand particles on the pipe walls or in specific areas. The larger diameter provides more space, allowing sand particles more opportunities to disperse or deposit during flow, rather than accumulating in certain parts of the pipe and causing blockages. In large-diameter pipes, fluid dynamics (such as turbulence) are more pronounced, which helps keep sand particles suspended in the fluid. Furthermore, the advantage of using a variable-area large-diameter flow meter 11 is that, compared to traditional fixed orifice plates and other throttling devices, the internal structure of the variable-area throttling element makes it less likely for sand particles to accumulate rapidly at the throttling point. Since the presence of sand particles causes changes in fluid velocity, the variable-area throttling element can better adapt to these velocity fluctuations. Traditional throttling devices calculate flow rate based on a fixed throttling area; when the flow velocity changes due to the influence of sand particles, the measurement error increases. The variable-area throttling element, however, can automatically adjust the throttling area according to the flow velocity, ensuring the accuracy of flow measurement to a certain extent.

[0073] 2. Second two-phase flow meter 9 for gas phase metering containing a small amount of liquid phase:

[0074] The second two-phase flow meter of this system uses the sampling noise method for metering, as detailed below:

[0075] Two-phase flow involving gas and liquid is characterized by the exchange of momentum, energy, and mass between the phases, with the liquid and gas phases distributed randomly in space and time. Differential pressure noise, or differential pressure pulsation, exists in orifice plate measurements of two-phase flow; this is a well-known physical phenomenon. Traditional measurement theory considers this noise as interference with the measurement and eliminates it through filtering. Modern measurement theory, however, views noise as an inherent physical characteristic of two-phase flow, serving as a carrier of information about the flow state and parameters.

[0076] These noise signals contain a wealth of information; their frequency components and amplitudes are closely related to the ratio of the gas and liquid phases, their flow rates, and their respective physical properties. The noise changes as the liquid content increases.

[0077] By analyzing the collected noise signals and combining them with a mathematical model established based on fluid mechanics theory and experimental data, parameters such as the flow rate and gas content of the gas and liquid phases in a gas-liquid two-phase flow can be derived.

[0078] 3. First two-phase flow meter 8 for liquid phase metering containing a small amount of gas phase:

[0079] The first two-phase flow meter 8 in this system is used for measurement and includes two sensors and a PT500 probe. The sensors can measure operating parameters such as the mixed density, working pressure, working temperature, and mixed flow rate. The flow computer 18 calculates the gas-liquid volume ratio, and the two-phase flow rate is calculated from the mixed flow rate and the gas-liquid volume ratio. When liquid or gas flows through the measuring tube, the Coriolis effect causes a phase shift on the sine wave, which is detected by the two sensors. The phase shift is proportional to the mass flow rate. Density is measured by vibration frequency measurement, temperature is measured by the PT500 probe, and pressure is detected by a pressure transmitter. The gas composition and liquid phase properties are preset. The gas density under operating conditions is calculated from the temperature and pressure detected by the sensors. Then, the liquid volume fraction (LVF) or gas volume fraction (GVF) is calculated from the liquid density, the operating gas density, and the mixed density detected by the sensors. Finally, the gas phase flow rate and liquid phase flow rate are calculated by the LVF or GVF and the mixed mass flow rate detected by the sensors using the mass flow meter 10.

[0080] 4. Mass flow meter for moisture content measurement:

[0081] The high-precision mass flow meter 10, as the core measuring component, can accurately measure parameters such as flow rate, mixing density, flow velocity, and temperature of oil-water mixtures. Given the significant density difference between water and oil, different water contents necessarily correspond to specific mixing density values. The intelligent optimization algorithm on the device continuously processes the measurement data, effectively correcting measurement deviations caused by factors such as fluid turbulence, temperature fluctuations, and complex changes.

[0082] Meanwhile, a capacitance sensor is installed in the sampling tube to form a complete measurement system. Given the significant difference in dielectric constant between water and oil, even under the complex state of high-temperature emulsification, the capacitance value will exhibit regular changes depending on the water content. This capacitance sensor captures the capacitance changes of the oil-water mixture in real time, providing auxiliary verification information for the measurement and further improving the accuracy and reliability of the water content measurement. When the density data measured by the mass flow meter 10 shows abnormal fluctuations or faces complex operating conditions, the capacitance change data fed back by the capacitance sensor can help the system quickly identify problems, calibrate in a timely manner, and ensure the stability of the entire measurement process.

[0083] The embodiments described above merely illustrate specific implementations of this utility model, and while the descriptions are detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A single well oil, gas and water three phase metering system suitable for use with sand, characterized in that, The system includes a flow computer (18), a sand separator (2), a gas-liquid separator (3), a moisture content measuring tube (4), a fluid inlet pipe (1), a fluid outlet pipe (14), and a manifold (19). The fluid inlet pipe (1) is connected to a separation metering tube (20), a sampling measuring tube (21), and a large-diameter measuring tube (22). The end of the separation metering tube (20) furthest from the fluid inlet pipe (1) is connected to the gas-liquid separator (3). The separation metering tube (20) is equipped with a second switching valve (6). The top of the gas-liquid separator (3) is connected to a first gas phase pipeline (23) that is internally connected to it. A second two-phase flow meter (9) is provided on the gas phase pipeline (23). A first liquid phase pipeline (24) communicating with the bottom of the gas-liquid separation pipe (3) is provided. A first two-phase flow meter (8) is provided on the first liquid phase pipeline (24). The end of the sampling and measuring pipe (21) away from the fluid inlet pipe (1) is connected to the sand separator (2). A first switch valve (5) is provided on the sampling and measuring pipe (21). The top of the sand separator (2) is connected to the moisture content measuring pipe (4) through the first connecting pipe (29). A sand discharge pipe (25) is provided at the bottom of the sand separator (2). A moisture content measuring pipe (4) is provided. The instrument (16) has an electric heating tape (26) wrapped around the outer surface of the moisture content measuring tube (4). The moisture content measuring tube (4) is connected to the first gas phase pipeline (23) near the top through a second gas phase pipeline (27). The bottom of the moisture content measuring tube (4) is provided with a second liquid phase pipeline (28) connected to it. A second regulating valve (17) and a mass flow meter (10) are sequentially provided on the second liquid phase pipeline (28) from one end near the moisture content measuring tube (4) to the other end away from the moisture content measuring tube (4). A third switching valve (7) and a large-diameter flow meter (10) are respectively provided on the large-diameter measuring tube (22). 11) The other ends of the first gas phase pipeline (23), the first liquid phase pipeline (24), the sand discharge pipe (25), the second liquid phase pipeline (28) and the large diameter measuring pipe (22) are all connected to the manifold (19), the manifold (19) is connected to the fluid outlet pipe (14), and the first switch valve (5), the second switch valve (6), the third switch valve (7), the first two-phase flow meter (8), the second two-phase flow meter (9), the water content meter (16), the electric heating tape (26), the second regulating valve (17), the mass flow meter (10) and the large diameter flow meter (11) are respectively connected to the flow computer (18).

2. A single well oil, gas and water three phase metering system suitable for use with sand according to claim 1, wherein, An inlet pressure gauge (12) is provided on the fluid inlet pipe (1).

3. The single well oil, gas and water three phase metering system for sand production according to claim 1, wherein, An outlet pressure gauge (13) is provided on the fluid outlet pipe (14).

4. A three-phase metering system for oil, gas, and water in a sand-bearing single well according to claim 1, characterized in that, The first liquid phase pipeline (24) is provided with a first regulating valve (15), which is connected to the flow computer (18).

5. A three-phase metering system for oil, gas, and water in a sand-bearing single well according to claim 1, characterized in that, The moisture content measuring tube (4) is equipped with a capacitive sensor, which is connected to the flow computer (18).

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