Coal bed gas well double-pipe jet pump and control method thereof

Abstract

The present application relates to the technical field of jet pump, especially to a coalbed methane well double-pipe jet pump and a control method thereof; the double-pipe jet pump comprises a jet pump, a flushing pipe, a check valve, a coupling, a tail pipe and a flushing valve core; the jet pump is connected with the flushing pipe; the check valve is arranged at the end of the flushing pipe away from the jet pump; the tail pipe is arranged at the end of the check valve away from the flushing pipe; the tail pipe is connected with the check valve by sleeving the coupling; the flushing pump core is further arranged in the flushing pipe; the flushing pump core moves along the axial direction of the flushing pipe in the flushing pipe by hydraulic pushing; the check valve is provided with a valve ball; the flushing valve core attracts the valve ball by setting electromagnetic force to control the check valve to be conducted in flushing; the inside of the double-pipe jet pump is descaled.

Description

Technical Field

[0001] This invention relates to the field of jet pump technology, and in particular to a dual-pipe jet pump for coalbed methane wells and its control method. Background Technology

[0002] In coalbed methane wells, jet pumps are rodless gas production and drainage devices that utilize the energy transfer of high-pressure hydraulic fluid to lift downhole fluids (such as coalbed methane produced water and pulverized coal) to the surface. This technology is particularly suitable for complex well conditions such as horizontal wells and multi-branch wells. Due to its advantages such as having no moving parts, simple structure, sand resistance, and corrosion resistance, it is widely used in coal gas fields.

[0003] During coalbed methane (CBM) drainage, the reduced drainage pressure leads to stress release in the overlying strata. Combined with fracturing fluid scouring and formation water soaking, the coal seam easily produces large amounts of coal dust and fine sand. During dual-tube jet pump drainage, some solid particles carried by the liquid enter the intake channel with the airflow. Due to the narrow flow path and throttling structure within the intake channel, particles easily deposit at corners and filters, gradually causing blockage. Furthermore, formation water in CBM wells often contains high concentrations of calcium, magnesium, and barium ions. When the dual-tube jet pump operates, the sudden pressure drop and temperature fluctuations in the intake channel disrupt the formation water dissolution balance, causing scale such as calcium carbonate and barium sulfate to crystallize and precipitate, adhering to the inner wall and flow path of the channel, accelerating the blockage process. In severe cases, the tools and tubing below the jet pump are completely blocked, making drainage work impossible. The only option is to pull out all tubing, jet pump, and downhole tools for maintenance. This not only increases operating costs but also stops drainage work and may even damage the formation.

[0004] Therefore, there is an urgent need to provide a dual-tube jet pump for coalbed methane wells and its control method, which, compared with the existing technology, removes scale from the inside of the dual-tube jet pump. Summary of the Invention

[0005] This invention addresses the technical problems existing in the prior art by providing a dual-pipe jet pump for coalbed methane wells and its control method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A dual-tube jet pump for coalbed methane wells includes a jet pump, a flushing pipe, a check valve, a coupling, a tailpipe, and a flushing valve core. The jet pump is connected to the flushing pipe. The check valve is located at the end of the flushing pipe away from the jet pump. The tailpipe is located at the end of the check valve away from the flushing pipe. The tailpipe is connected to the check valve by a coupling. The flushing pump core is also located inside the flushing pipe. The flushing pump core is hydraulically pushed inside the flushing pipe and moves along the axial direction of the flushing pipe. The check valve has a valve ball inside. The flushing valve core attracts the valve ball by electromagnetic force, controlling the flow of the check valve during flushing.

[0008] Furthermore, the flushing pump core includes a cylindrical part and an insertion head, the cylindrical part and the insertion head are integrally connected, both the cylindrical part and the insertion head have through holes inside, the insertion head is retracted away from the cylindrical part, the end of the insertion head away from the cylindrical part is provided with an electromagnet, and the valve ball has a groove on its outer side, the groove being adapted to the shape of the electromagnet; when flushing is required, the insertion head is connected to the groove by hydraulic pushing action, the electromagnet is energized, causing the insertion head to attract the valve ball, and then the valve ball is moved by hydraulic pushing action, controlling the one-way valve to open.

[0009] Furthermore, the one-way valve includes a one-way valve body, a one-way valve seat, and a valve ball. One end of the one-way valve body is connected between the jet pump and the flushing pipe, and the other end of the one-way valve body is detachably and fixedly connected to the coupling. The one-way valve seat is fixedly installed inside the one-way valve body, and the valve ball is movably connected inside the one-way valve seat.

[0010] A flow rate sensor and a density sensor are embedded on the inner wall of the valve seat where it contacts the valve ball. The flow rate sensor is used to monitor the flow rate of the flushing fluid passing through the valve seat of the one-way valve, and the density sensor is used to detect the density of the liquid passing through the valve seat of the one-way valve. Both the flow rate sensor and the distance sensor are electrically connected to the controller. The controller is equipped with a control module. The control module obtains the electromagnetic force applied to the electromagnet based on the flow rate value detected by the flow rate sensor and the liquid density detected by the density sensor.

[0011] A control method for a dual-tube jet pump in a coalbed methane well includes the following steps:

[0012] S1. Under the action of hydraulic push, the flushing pump core moves towards the valve ball, so that the insert head is inserted into the slot, and the electromagnet is energized so that the electromagnet has basic electromagnetic force.

[0013] S2. Under the action of hydraulic push, the flushing pump core drives the valve ball to move a set distance away from the valve seat of the single-flow valve. Then, the control module adjusts the electromagnetic force of the electromagnet to the initial electromagnetic force according to the initial flow rate of the flushing fluid, releases the flushing fluid, and performs flushing operation on the inside of the pipeline.

[0014] S3. During the flushing process, multiple monitoring time points are set. At each monitoring time point, the real-time flow rate value detected by the flow rate sensor and the real-time liquid density detected by the density sensor are acquired. The control module then inputs the real-time flow rate value into the flushing fluid flow rate calculation model of the valve ball action force. 1. Incorporate real-time liquid density into liquid density In the process, the force exerted by the corresponding flushing fluid on the valve ball is calculated and used as the real-time electromagnetic force at the next time point;

[0015] S4. After performing N flushing operations using steps S1-S3, construct a line graph corresponding to the real-time electromagnetic force and monitoring time for each flushing operation. Classify the corresponding line graphs according to the degree of scaling, obtain a comprehensive line graph for each type of scaling degree, and store the scaling degree and comprehensive line graph in the database.

[0016] S5. During subsequent flushing operations, based on the degree of scaling, obtain a comprehensive line graph corresponding to the scaling degree classification. Use the average electromagnetic force of the first monitoring time in the comprehensive line graph as the electromagnetic force at the first monitoring time point. For each subsequent monitoring time, calculate the real-time electromagnetic force and use the real-time electromagnetic force to correct the average electromagnetic force to obtain the corrected electromagnetic force. Use the corrected electromagnetic force as the electromagnetic force for the next monitoring time to perform the flushing operation.

[0017] S6. Generate a corresponding line chart from the rinsing operation performed in step S5, and use the resulting line chart in obtaining the comprehensive line chart in step S4.

[0018] Furthermore, the control module calculates the initial electromagnetic force of the electromagnet using a valve ball force calculation model, which is expressed by the following formula:

[0019] ;

[0020] In the above formula, This indicates the force exerted by the flushing fluid on the valve ball. Indicates the flow rate of the flushing fluid. This indicates the area of ​​the valve ball that is acted upon by the flushing fluid. This indicates the pressure difference between the valve ball and the flushing fluid in the upstream and downstream directions. Indicates the density of the liquid;

[0021] The initial flow velocity of the flushing fluid is incorporated into the calculation model of the valve ball force. At the same time, it brings the density of the rinsing fluid into Calculated This is the initial electromagnetic force.

[0022] Furthermore, the specific method for obtaining the comprehensive line graph in step S4 is as follows: mark the degree of scaling before the flushing operation on each corresponding line graph; classify the degree of scaling for each flushing operation according to the K-means clustering analysis method; divide the corresponding line graph of the scaling degree in each cluster into categories; for each category of corresponding line graph, take the average value of the real-time electromagnetic force corresponding to the corresponding monitoring time as the average electromagnetic force for that monitoring time, thereby forming a comprehensive line graph of the scaling degree of that category.

[0023] Furthermore, the degree of scaling is obtained by measuring the thickness of the pipe wall. The difference between the pipe wall thickness measured before the flushing operation and the actual thickness of the pipe wall is used as a quantitative value reflecting the degree of scaling.

[0024] Furthermore, the corresponding time-to-time ratio is plotted on the horizontal axis and the real-time electromagnetic force is plotted on the vertical axis in the time-to-time ratio plot.

[0025] Furthermore, the corrected electromagnetic force is calculated using the following formula:

[0026] ;

[0027] In the above formula, This represents the corrected electromagnetic force at the i-th monitoring time point. Indicates the first weight. Indicates the second weight. This represents the average electromagnetic force at the i-th monitoring time point. This represents the real-time electromagnetic force at the i-th monitoring time point.

[0028] Furthermore, , Take 0.5 for all.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] (1) This invention sets up a flushing pump core and an insertion head on the flushing pump core. An electromagnet is set on the insertion head. The electromagnet attracts the valve ball. During the flushing process, the electromagnet on the insertion head is energized by hydraulic pushing to attract the valve ball and bring the valve ball away from the valve seat of the one-way valve, so that there is a gap between the valve ball and the valve seat of the one-way valve, so that the flushing liquid can flow normally into the tail pipe for descaling operation. This can achieve comprehensive descaling in the dual-pipe jet pump.

[0031] (2) By setting up a flow rate sensor and a density sensor, the present invention can obtain the real-time electromagnetic force through the control module, ensuring the attraction between the electromagnet and the valve ball, and preventing the valve ball from separating from the electromagnet under the action of the flushing liquid. Furthermore, based on the classification of dual-tube jet pumps with different scaling degrees, the corresponding line graphs of dual-tube jet pumps with the same scaling degree are classified and analyzed to obtain a comprehensive line graph. In subsequent flushing operations, the average electromagnetic force and the real-time electromagnetic force are comprehensively analyzed to obtain the corrected electromagnetic force. The flushing parameters of the same scaling degree and the real-time flushing parameters can be combined simultaneously to achieve accurate acquisition of the electromagnetic force between the electromagnet and the valve ball, further ensuring the attraction between the electromagnet and the valve ball. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0033] Figure 2 This is a schematic diagram showing the structure of the single-flow valve of the present invention.

[0034] Figure 3 This is a schematic diagram of the flushing pump core of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Jet pump; 2. Flushing pipe; 3. Check valve body; 4. Check valve seat; 5. Valve ball; 6. Coupling; 7. Tail pipe; 8. Flushing pump core; 9. Insertion head. Detailed Implementation

[0037] The technical solution of the present invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. It should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0038] like Figure 1 , Figure 2 , Figure 3As shown, the present invention provides a dual-pipe jet pump for coalbed methane wells, including a jet pump 1, a flushing pipe 2, a check valve, a coupling 6, a tail pipe 7, and a flushing valve core. The jet pump 1 is connected to the flushing pipe 2. A check valve is provided at the end of the flushing pipe 2 away from the jet pump 1. A tail pipe 7 is provided at the end of the check valve away from the flushing pipe 2. The tail pipe 7 is connected to the check valve by a coupling 6. A flushing pump core 8 is also provided inside the flushing pipe 2. The flushing pump core 8 moves along the axial direction of the flushing pipe 2 inside the flushing pipe 2 by hydraulic pushing, thereby controlling the flow of the check valve during flushing.

[0039] The one-way valve includes a one-way valve body 3, a one-way valve seat 4, and a valve ball 5. One end of the one-way valve body 3 is located between the jet pump 1 and the flushing pipe 2, and the one-way valve body 3 is connected to the jet pump 1 and the flushing pipe 2. The other end of the one-way valve body 3 is detachably and fixedly connected to the coupling 6. The one-way valve seat 4 is fixedly installed inside the one-way valve body 3, and the valve ball 5 is movably connected inside the one-way valve seat 4. The valve ball 5 will only have a gap with the one-way valve seat 4 when pushed by the liquid flowing from the tail pipe 7 towards the flushing pipe 2, and the one-way valve will only open. When there is liquid flowing from the flushing pipe 2 to the tail pipe 7, the valve ball 5 and the one-way valve seat 4 are tightly fitted, and the one-way valve is closed.

[0040] The flushing pump core 8 includes a cylindrical part and an insertion head 9, which are integrally connected. Both the cylindrical part and the insertion head 9 have through holes inside. The insertion head 9 is designed to retract away from the cylindrical part. An electromagnet is provided at the end of the insertion head 9 away from the cylindrical part. A slot is provided on the outside of the valve ball 5, and the slot is adapted to the shape of the electromagnet. When flushing is required, the flushing pump core 8 moves towards the valve ball 5 through hydraulic pushing. The insertion head 9 of the valve ball 5 slides into the slot. The electromagnet is energized, causing the insertion head 9 to attract the valve ball 5. Then, through hydraulic pushing, the flushing pump core 8 drives the attracted valve ball 5 to move away from the one-way valve seat 4 and to a set distance, so that the flushing fluid can pass through the one-way valve for flushing.

[0041] A flow rate sensor and a density sensor are embedded on the inner wall of the valve seat 4 of the one-way valve that contacts the valve ball 5. The flow rate sensor is used to monitor the flow rate of the flushing fluid passing through the valve seat 4 of the one-way valve, and the density sensor is used to detect the density of the liquid passing through the valve seat 4 of the one-way valve. The flow rate sensor and the distance sensor are electrically connected to the controller. The controller is equipped with a control module. The control module obtains the electromagnetic force applied to the electromagnet based on the flow rate value detected by the flow rate sensor and the liquid density detected by the density sensor.

[0042] The present invention also provides a control method for a dual-tube jet pump in a coalbed methane well, comprising the following steps:

[0043] S1. Under the action of hydraulic push, the flushing pump core 8 moves towards the valve ball 5, so that the insert head 9 is inserted into the slot, and the electromagnet is energized, so that the electromagnet has a basic electromagnetic force. The basic electromagnetic force is the force that makes the valve ball 5 and the electromagnet attract each other in the absence of other external forces.

[0044] S2. Under the action of hydraulic push, the flushing pump core 8 drives the valve ball 5 to move a set distance away from the valve seat 4 of the single-flow valve. Then, the control module adjusts the electromagnetic force of the electromagnet to the initial electromagnetic force according to the initial flow rate of the flushing fluid, releases the flushing fluid, and performs flushing operation on the inside of the pipeline.

[0045] The initial electromagnetic force of the electromagnet is calculated in the control module using the force calculation model of valve ball 5. The force calculation model of valve ball 5 is expressed by the following formula:

[0046] ;

[0047] In the above formula, This indicates the force exerted by the flushing fluid on valve ball 5, in N ( ). ); Indicates the flow rate of the flushing fluid, in m / s; This indicates the area of ​​valve ball 5 that is acted upon by the flushing fluid, in units of... ; This indicates the pressure difference of valve ball 5 in the upstream and downstream directions of the flushing fluid, in Pa (Pa). ); Represents liquid density, unit .

[0048] The method for obtaining the area of ​​the valve ball 5 affected by the flushing fluid is as follows: the surface area of ​​the valve ball 5 minus the area of ​​the groove mapped on the outer surface of the valve ball 5; the method for obtaining the pressure difference of the valve ball 5 in the upstream and downstream directions of the flushing fluid is as follows: two pressure sensors are set in the valve seat 4 of the single-flow valve, one pressure sensor is set on the upstream side of the valve ball 5 in the flushing fluid, and the other sensor is set on the downstream side of the valve ball 5 in the flushing fluid. The pressure difference of the valve ball 5 in the upstream and downstream directions of the flushing fluid is obtained by calculating the difference between the pressure values ​​detected by the two pressure sensors at the same time.

[0049] The initial flow velocity of the flushing fluid is incorporated into the force calculation model of valve ball 5. At the same time, it brings the density of the rinsing fluid into Calculated This is the initial electromagnetic force.

[0050] S3. During the flushing process, multiple monitoring time points are set, with the same time difference between any two adjacent monitoring time points. At each monitoring time point, the real-time flow rate value detected by the flow velocity sensor and the real-time liquid density detected by the density sensor are acquired. The control module then inputs the real-time flow rate value into the flushing fluid flow rate calculation model of the valve ball 5. 1. Incorporate real-time liquid density into liquid density In the process, the force exerted by the corresponding flushing fluid on valve ball 5 is calculated and used as the real-time electromagnetic force at the next time point.

[0051] S4. After performing N flushing operations using steps S1-S3, construct a line graph corresponding to the real-time electromagnetic force and monitoring time for each flushing operation. In each corresponding line graph, the monitoring time is plotted on the horizontal axis and the real-time electromagnetic force on the vertical axis. Mark the degree of scaling before the flushing operation on each corresponding line graph. The degree of scaling is obtained by measuring the thickness of the pipe wall. The difference between the pipe wall thickness measured before the flushing operation and the actual thickness of the pipe wall is used as a quantitative value reflecting the degree of scaling. Classify the degree of scaling for each flushing operation using the K-means clustering analysis method. Divide the corresponding line graph of the scaling degree in each cluster into categories. For each category of corresponding line graphs, take the average of the real-time electromagnetic force corresponding to the corresponding monitoring time as the average electromagnetic force for that monitoring time, thus forming a comprehensive line graph of the scaling degree for that category. Store the scaling degree and the comprehensive line graph in the database.

[0052] S5. During subsequent flushing operations, a comprehensive line graph corresponding to the scale level classification is obtained based on the scale level. The flushing operation is performed based on the average electromagnetic force of the first monitoring time in the comprehensive line graph. Furthermore, during the flushing operation, the real-time electromagnetic force is calculated for each subsequent monitoring time. The average electromagnetic force is corrected using the real-time electromagnetic force to obtain the corrected electromagnetic force. The corrected electromagnetic force is then used as the electromagnetic force for the next monitoring time to perform the flushing operation.

[0053] The corrected electromagnetic force is calculated using the following formula:

[0054] ;

[0055] In the above formula, This represents the corrected electromagnetic force at the i-th monitoring time point. Indicates the first weight. Indicates the second weight. This represents the average electromagnetic force at the i-th monitoring time point. This represents the real-time electromagnetic force at the i-th monitoring time point.

[0056] , Take 0.5 for all.

[0057] S6. Generate a corresponding line chart from the rinsing operation performed in step S5, and use the resulting line chart in obtaining the comprehensive line chart in step S4.

[0058] This invention features a flushing pump core 8 with an insertion head 9 and an electromagnet on the insertion head 9. The electromagnet attracts the valve ball 5. During flushing, the electromagnet on the insertion head 9 is energized by hydraulic pushing, attracting the valve ball 5 and pulling it away from the one-way valve seat 4. This creates a gap between the valve ball 5 and the one-way valve seat 4, allowing the flushing fluid to flow normally into the tailpipe 7 for descaling. This invention enables comprehensive descaling within the dual-pipe jet pump 1.

[0059] This invention, by setting up flow rate and density sensors and controlling the module, can obtain real-time electromagnetic force, ensuring the attraction between the electromagnet and the valve ball 5, and preventing the valve ball 5 from separating from the electromagnet under the action of the flushing fluid. Furthermore, based on the classification of dual-tube jet pumps 1 with different scaling levels, the corresponding line graphs of dual-tube jet pumps 1 with the same scaling level are categorized and analyzed to obtain a comprehensive line graph. In subsequent flushing operations, the average electromagnetic force and real-time electromagnetic force are comprehensively analyzed to obtain a corrected electromagnetic force. This allows for the accurate acquisition of the electromagnetic force between the electromagnet and the valve ball 5 by simultaneously combining flushing parameters for the same scaling level and real-time flushing parameters, further ensuring the attraction between the electromagnet and the valve ball 5.

[0060] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A control method for a dual-tube jet pump in a coalbed methane well, characterized in that, The coalbed methane well dual-pipe jet pump includes a jet pump, a flushing pipe, a check valve, a coupling, a tailpipe, and a flushing valve core. The jet pump is connected to the flushing pipe. The check valve is located at the end of the flushing pipe away from the jet pump. The tailpipe is located at the end of the check valve away from the flushing pipe. The tailpipe is connected to the check valve by a coupling. The flushing pipe also contains a flushing pump core, which is hydraulically pushed to move along the axial direction of the flushing pipe. The check valve contains a valve ball, and the flushing valve core attracts the valve ball by electromagnetic force, controlling the flow of the check valve during flushing. The control method for the dual-tube jet pump in the coalbed methane well includes the following steps: S1. Under the action of hydraulic push, the flushing pump core moves towards the valve ball, so that the insert head is inserted into the slot, and the electromagnet is energized so that the electromagnet has basic electromagnetic force. S2. Under the action of hydraulic push, the flushing pump core drives the valve ball to move a set distance away from the valve seat of the single-flow valve. Then, the control module adjusts the electromagnetic force of the electromagnet to the initial electromagnetic force according to the initial flow rate of the flushing fluid, releases the flushing fluid, and performs flushing operation on the inside of the pipeline. S3. During the flushing process, multiple monitoring time points are set. At each monitoring time point, the real-time flow rate value detected by the flow rate sensor and the real-time liquid density detected by the density sensor are acquired. The control module then inputs the real-time flow rate value into the flushing fluid flow rate calculation model of the valve ball action force.

1. Incorporate real-time liquid density into liquid density In the process, the force exerted by the corresponding flushing fluid on the valve ball is calculated and used as the real-time electromagnetic force at the next time point; S4. After performing N flushing operations using steps S1-S3, construct a line graph corresponding to the real-time electromagnetic force and monitoring time for each flushing operation. Classify the corresponding line graphs according to the degree of scaling, obtain a comprehensive line graph for each type of scaling degree, and store the scaling degree and comprehensive line graph in the database. S5. During subsequent flushing operations, based on the degree of scaling, obtain a comprehensive line graph corresponding to the scaling degree classification. Use the average electromagnetic force of the first monitoring time in the comprehensive line graph as the electromagnetic force at the first monitoring time point. For each subsequent monitoring time, calculate the real-time electromagnetic force and use the real-time electromagnetic force to correct the average electromagnetic force to obtain the corrected electromagnetic force. Use the corrected electromagnetic force as the electromagnetic force for the next monitoring time to perform the flushing operation. S6. Generate a corresponding line chart from the rinsing operation performed in step S5, and use the resulting line chart in obtaining the comprehensive line chart in step S4. The initial electromagnetic force of the electromagnet is calculated in the control module using a valve ball force calculation model, which is expressed by the following formula: ； In the above formula, This indicates the force exerted by the flushing fluid on the valve ball. This indicates the flow rate of the flushing fluid. This indicates the area of ​​the valve ball that is acted upon by the flushing fluid. This indicates the pressure difference between the valve ball and the flushing fluid in the upstream and downstream directions. Indicates the density of the liquid; The initial flow velocity of the flushing fluid is incorporated into the calculation model of the valve ball force. At the same time, it brings the density of the rinsing fluid into Calculated This is the initial electromagnetic force.

2. The control method for a dual-pipe jet pump in a coalbed methane well according to claim 1, characterized in that, The flushing pump core includes a cylindrical part and an insertion head. The cylindrical part and the insertion head are integrally connected. Both the cylindrical part and the insertion head have through holes inside. The insertion head is retracted away from the cylindrical part. An electromagnet is provided at the end of the insertion head away from the cylindrical part. A slot is provided on the outside of the valve ball. The slot is adapted to the shape of the electromagnet. When flushing is required, the insertion head is connected to the slot by hydraulic pushing. The electromagnet is energized, causing the insertion head to attract the valve ball. Then, by hydraulic pushing, the valve ball is moved, controlling the one-way valve to open.

3. The control method for a dual-tube jet pump in a coalbed methane well according to claim 2, characterized in that, The one-way valve includes a one-way valve body, a one-way valve seat, and a valve ball. One end of the one-way valve body is connected between the jet pump and the flushing pipe, and the other end of the one-way valve body is detachably and fixedly connected to the coupling. The one-way valve seat is fixedly installed inside the one-way valve body, and the valve ball is movably connected inside the one-way valve seat. A flow rate sensor and a density sensor are embedded on the inner wall of the valve seat where it contacts the valve ball. The flow rate sensor is used to monitor the flow rate of the flushing fluid passing through the valve seat of the one-way valve, and the density sensor is used to detect the density of the liquid passing through the valve seat of the one-way valve. Both the flow rate sensor and the distance sensor are electrically connected to the controller. The controller is equipped with a control module. The control module obtains the electromagnetic force applied to the electromagnet based on the flow rate value detected by the flow rate sensor and the liquid density detected by the density sensor.

4. The control method for a dual-tube jet pump in a coalbed methane well according to claim 1, characterized in that, The specific method for obtaining the comprehensive line chart in step S4 is as follows: Mark the degree of scaling before the flushing operation on each corresponding line chart. Classify the degree of scaling for each flushing operation using the K-means clustering analysis method. Divide the corresponding line chart for the degree of scaling in each cluster into categories. For each category of the corresponding line chart, take the average value of the real-time electromagnetic force corresponding to the corresponding monitoring time as the average electromagnetic force for that monitoring time, thereby forming a comprehensive line chart of the degree of scaling for that category.

5. The control method for a dual-tube jet pump in a coalbed methane well according to claim 4, characterized in that, The degree of scaling is obtained by measuring the thickness of the pipe wall. The difference between the pipe wall thickness measured before the flushing operation and the actual thickness of the pipe wall is used as a quantitative value to reflect the degree of scaling.

6. The control method for a dual-tube jet pump in a coalbed methane well according to claim 1, characterized in that, The corresponding time-to-time graph is plotted with monitoring time on the horizontal axis and real-time electromagnetic force on the vertical axis.

7. The control method for a dual-tube jet pump in a coalbed methane well according to claim 1, characterized in that, The corrected electromagnetic force is calculated using the following formula: ； In the above formula, This represents the corrected electromagnetic force at the i-th monitoring time point. Indicates the first weight. Indicates the second weight. This represents the average electromagnetic force at the i-th monitoring time point. This represents the real-time electromagnetic force at the i-th monitoring time point.

8. The control method for a dual-pipe jet pump in a coalbed methane well according to claim 7, characterized in that, , Take 0.5 for all.

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