Device and method for testing solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions

Abstract

The application discloses a device and method for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions, and belongs to the technical field of solubility testing technology of methane in oil-based drilling fluid.The device comprises a tank body, a supporting seat, an observation window, a detector, a disc cover, a piston disc, a sealing ring, a vertical pipe, a corrugated flexible sleeve, a second air pump, a hose, an inlet and outlet liquid valve, a breather valve, an air inlet valve, a heating disc and a temperature sensor.The method comprises the following steps: loading the oil-based drilling fluid, loading the methane gas, heating and pressurizing, auxiliary dissolving, rotating mixing and measuring.The application has the advantages that the methane gas can be easily diffused and uniformly mixed into the oil-based drilling fluid, the solubility of the methane gas in the oil-based drilling fluid is greatly improved, the overall experimental speed is facilitated, the experimental time is saved, and the overall use effect is good.

Description

Technical Field

[0001] This invention belongs to the field of solubility testing technology for methane in oil-based drilling fluids, and relates to a solubility testing experimental device and method, specifically a solubility testing experimental device and method for methane in oil-based drilling fluids under high temperature and high pressure conditions. Background Technology

[0002] The solubility test of methane in oil-based drilling fluids generally needs to be conducted experimentally. The experiment is usually carried out in a high-temperature and high-pressure environment. The amount of methane dissolved in the oil-based drilling fluid is detected by instruments to determine the solubility.

[0003] In an experimental apparatus for determining the dissolution rate of gas in oil-based drilling fluid during drilling gas intrusion, as disclosed in CN111272952B, the gas can be dissolved in the oil-based drilling fluid for the experiment; however, it has the following drawbacks: it is not easy to improve the gas dissolution efficiency, it is not easy to make the gas dissolve quickly in the oil-based drilling fluid, and the dissolution efficiency is relatively slow.

[0004] In the high-temperature and high-pressure natural gas solubility test reactor, apparatus and method in application number CN202011456442.9, an electromagnetic stirrer is optionally used at the bottom to stir the oil base. The main purpose is to make the drilling fluid reach thermal equilibrium quickly, but it has very limited help in the rapid dissolution of gas into the drilling fluid.

[0005] Therefore, this invention adopts a design that improves dissolution efficiency and allows the introduced gas to diffuse, and proposes an experimental apparatus and method for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions to address the above-mentioned problems. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this application provides an experimental apparatus and method for testing the solubility of methane in oil-based drilling fluids under high temperature and high pressure conditions, thereby solving the problem of low dissolution efficiency in existing technologies. Furthermore, it addresses the issue of the inability to rapidly and uniformly diffuse methane into the oil-based drilling fluid. A bottom-mounted stirring motor drives the stirring blades to rotate, mixing the oil-based drilling fluid internally. A second gas pump then delivers methane gas, which diffuses through multiple evenly distributed vertical pipes and is discharged into the oil-based drilling fluid through fine holes. The even distribution of these pipes facilitates diffusion into the oil-based drilling fluid. Moreover, when introducing methane into the oil-based drilling fluid, a rotating disc cover is activated, causing the structure below the disc cover to rotate as well. This causes the multiple vertical pipes to rotate together, ensuring a uniform supply of methane gas to the oil-based drilling fluid. Through these methods, the dissolution rate of methane gas in the oil-based drilling fluid is significantly improved, increasing the overall experimental speed, saving experimental time, and resulting in better overall performance.

[0007] The objective of this invention is achieved through the following technical solution: An experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions includes: a tank, a vertical pipe, and a second air pump; wherein, a support base is fixedly installed at the bottom of the tank, an observation window is provided on the front of the tank, and a detector is installed on the front of the tank; an automatically rotatable disc cover is provided at the top opening of the tank, and a height-adjustable piston disc is provided below the disc cover; a sealing ring is fixedly fitted on the cylindrical surface of the piston disc, and the sealing ring is in close contact with the inner wall of the tank; a plurality of through holes are evenly opened on the surface of the piston disc, the vertical pipe passes through the through holes, and the top end of the vertical pipe is fixedly connected to the bottom of the disc cover; a corrugated flexible sleeve is fitted on the vertical pipe, and the top end of the corrugated flexible sleeve is fixedly connected to the bottom of the disc cover, and the corrugated flexible sleeve is fixedly connected to the bottom of the disc cover. The bottom end of the corrugated flexible sleeve is fixedly connected to the top of the piston disc, and the bottom end of the corrugated flexible sleeve communicates with the through hole; the lower part of the vertical tube has multiple fine holes evenly spaced along its length, and the bottom end of the vertical tube is closed; a second air pump is fixedly installed on the top of the piston disc, the air inlet of the second air pump penetrates the piston disc, and the bottom end of the air inlet of the second air pump is located below the piston disc, and the air outlet of the second air pump is connected to a flexible hose, which communicates with a cavity set inside the disc cover, and the top end of the vertical tube is also connected to a cavity inside the disc cover; an inlet / outlet valve and a vent valve are installed on one side of the tank, and an air inlet valve is installed on the other side of the tank; a heating plate is installed on the bottom inner wall of the tank; multiple temperature sensors are evenly spaced along the height direction on the inner wall of the tank.

[0008] Furthermore, a stirring motor is provided at the bottom of the tank. Multiple fixing brackets are evenly fixedly installed on the outer wall of the housing of the stirring motor. The fixing brackets are fixedly connected to the bottom outer wall of the tank. A stirring blade is fixedly installed at the output shaft end of the stirring motor, and the stirring blade is located above the bottom inner wall of the tank.

[0009] Furthermore, a gear ring is fixedly installed at the bottom of the disc cover, and a third cylindrical gear is meshed with one side of the outer ring of the gear ring. A second drive motor is provided below the third cylindrical gear, and the output shaft of the second drive motor is fixedly sleeved with the third cylindrical gear. A fixing plate is fixedly installed on the second drive motor, and the fixing plate is fixedly installed on the inner wall of one side of the top of the tank. The disc cover is clearance-fitted with the opening at the top of the tank.

[0010] Furthermore, the disc cover has a mounting hole in the middle, and a rotating nut is fitted into the mounting hole with clearance. The rotating nut is a rotating body structure, and a screw is threadedly connected to the rotating nut. The bottom end of the screw is fixedly connected to the middle of the piston disc. Multiple guide rods are fixedly installed on the top surface of the piston disc. The guide rods pass through guide holes in the disc cover. A first cylindrical gear is fixedly sleeved on the top end of the rotating nut. The disc cover has a top hole.

[0011] Furthermore, the first cylindrical gear is meshed with a second cylindrical gear, a fixed bracket is fixedly installed on the disc cover, a first drive motor is fixedly installed on the fixed bracket, and the output shaft of the first drive motor is fixedly sleeved with the second cylindrical gear.

[0012] Furthermore, both the first drive motor and the second drive motor are composed of a housing, a rotating motor, a rotating shaft, a worm gear, and a worm. The rotating motor is fixedly installed on the outer wall of the housing, and the worm and the rotating shaft are rotatably installed inside the housing. The worm gear is fixedly sleeved on the rotating shaft, and the worm gear meshes with the worm. One end of the worm is fixedly connected to the output shaft end of the rotating motor.

[0013] Furthermore, a first air pump is fixedly installed on the top of the piston disc, and a second electrically controlled valve is installed at the outlet end of the first air pump. The second electrically controlled valve is connected to a third connecting pipe, which communicates with the air chamber inside the sealing ring. The air chamber inside the sealing ring is also connected to the first connecting pipe and the second connecting pipe. A first electrically controlled valve is installed at one end of the first connecting pipe, and the first electrically controlled valve is installed on the top of the piston disc. A second pressure sensor is installed at one end of the second connecting pipe, and the second pressure sensor is installed on the top of the piston disc.

[0014] Furthermore, a control box and a second wireless module are provided on the top of the piston disc. The control box contains a second controller and a power supply. A first pressure sensor is provided at the center of the bottom of the piston disc. The second wireless module and the first pressure sensor are both electrically connected to the second controller. The second controller is also electrically connected to a first air pump, a second air pump, a first electrically controlled valve, and a second electrically controlled valve.

[0015] Furthermore, a control cabinet is fixedly installed on one outer wall of the tank. The control cabinet contains a first wireless module and a first controller. The first wireless module is electrically connected to the first controller and is also electrically connected to a second wireless module. The first controller is also electrically connected to a detector, a rotating motor, a stirring motor, a heating plate, and a temperature sensor.

[0016] An experimental method for testing the solubility of methane in oil-based drilling fluids under high temperature and high pressure conditions includes the following steps: Step 1: Loading oil-based drilling fluid. Open the inlet and outlet valves and the vent valve. Flow oil-based drilling fluid through the inlet and outlet valves until the tank is full of oil-based drilling fluid at the position below the vent valve. When flowing oil-based drilling fluid, observe through the observation window to determine the fluid level. Then close the inlet and outlet valves and the vent valve. Step 2: Methane gas loading. The gas is connected to an external gas supply device through the inlet valve. The first drive motor drives the second cylindrical gear to rotate. Through the meshing transmission between the second cylindrical gear and the first cylindrical gear, the rotating nut can rotate, causing the rotating nut to turn around the screw. With the guidance of the guide rod and guide hole, the piston disc is vertically driven, causing the piston disc to move upward and move to a high position in the tank. When the piston disc moves upward, it provides suction to the space in the tank at the bottom of the piston disc. Methane is loaded into the tank through the gas supply device, and then the inlet valve is closed. Step 3: Heating and pressurization. Heating is performed by a heating plate to raise the internal temperature of the tank, creating a high-temperature environment. A temperature sensor detects the internal temperature and provides feedback to the control cabinet for temperature control. A piston disc is driven downwards to increase the pressure of the methane gas, creating a high-pressure environment. The pressure is sensed by a first pressure sensor and transmitted to a second controller. The second controller processes the pressure and transmits the signal wirelessly to the control cabinet via a second wireless module. The first wireless module receives the signal and transmits it to the first controller, which then controls the first drive motor to adjust the pressure and thus control the high pressure and high temperature of the internal environment. Step 4, assisted dissolution: Under specific high pressure and high temperature conditions, the second air pump draws methane gas from the bottom of the piston disc, allowing the methane gas to enter the cavity through the hose, providing methane gas to the top of the riser. The gas is transported through the riser and discharged through the fine holes at the bottom of the riser, allowing the gas to enter the oil-based drilling fluid. Through multiple evenly distributed risers, the introduced gas is dispersed to different locations in the oil-based drilling fluid. Step 5: Rotation and Mixing. Driven by a stirring motor, the stirring blades rotate to agitate the internal oil-based drilling fluid, facilitating the mixing of the introduced gas. Further driven by a second drive motor, the third cylindrical gear rotates. Through the meshing transmission between the third cylindrical gear and the gear ring, the disc cover rotates, and the structure below the disc cover, including the piston disc, also rotates. During rotation, the second air pump continuously supplies air, so that as the vertical pipe rotates, air is continuously discharged, which can further improve the dispersion of the introduced gas into the oil-based drilling fluid and facilitate dissolution. Step 6: Measurement. After dissolution, the methane in the oil-based drilling fluid is measured using a detector to complete the experiment.

[0017] The beneficial effects of this technical solution are as follows: This invention provides an experimental apparatus and method for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions. The apparatus and method proposed in this application can provide different high temperature and high pressure environments. Solubility is detected using a detector. Compared with traditional techniques, it facilitates the diffusion and uniform mixing of methane gas into the oil-based drilling fluid. Specifically, a bottom-mounted stirring motor drives the stirring blades to rotate, enabling internal mixing and stirring of the oil-based drilling fluid. Furthermore, a second gas pump delivers methane gas through multiple uniform... The distributed risers diffuse the methane gas into the oil-based drilling fluid through fine holes. Their even distribution facilitates diffusion into the fluid. Furthermore, when methane is introduced into the drilling fluid, the disc cover rotates, causing the structure beneath it to rotate as well. This results in multiple risers moving in a circular motion, ensuring a uniform supply of methane gas to the drilling fluid. This significantly improves the dissolution rate of methane gas in the drilling fluid, increasing the overall experimental speed, saving experimental time, and demonstrating good overall performance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the invention's structure; Figure 2 yes Figure 1 The diagram shows the internal structure of the tank in the embodiment shown. Figure 3 yes Figure 2 An enlarged structural diagram of part A in the embodiment shown; Figure 4 yes Figure 1 The schematic diagram of the cross-sectional structure of the piston disc and sealing ring in the embodiment shown; Figure 5 yes Figure 1 The schematic diagram of the gear ring and the third cylindrical gear in the embodiment shown is as follows; Figure 6 yes Figure 1 A schematic diagram of the structure of the disc cover in the embodiment shown; Figure 7 yes Figure 1 A schematic diagram of the structure of the first drive motor in the embodiment shown; Figure 8 yes Figure 1 A three-dimensional structural diagram of the rotating nut in the illustrated embodiment; Figure 9 yes Figure 1The diagram shows the structure of the bottom of the tank in the embodiment shown. Figure 10 This is a schematic diagram illustrating the working principle of this application.

[0019] The meanings of the reference numerals in the figure are as follows: 1. Tank body; 2. Support base; 3. Inlet / outlet valve; 4. Vent valve; 5. Observation window; 6. Detector; 7. Air inlet valve; 8. Disc cover; 801. Cavity; 9. Guide hole; 10. Guide rod; 11. Rotating nut; 12. First cylindrical gear; 13. Screw; 14. Fixed bracket; 15. First drive motor; 1501. Housing; 1502. Rotating motor; 1503. Rotating shaft; 1504. Worm gear; 1505. Worm; 16. Second cylindrical gear; 17. Control cabinet; 1701. First controller; 1702. First wireless module; 18. Mounting hole; 19. Gear ring; 20. Piston disc; 21. Sealing ring; 22. 23. Corrugated flexible sleeve; 24. Vertical pipe; 25. Fine hole; 26. Stirring motor; 27. Stirring blade; 28. Heating plate; 29. ​​Temperature sensor; 30. First pressure sensor; 31. Second wireless module; 32. Second pressure sensor; 33. First electrically controlled valve; 34. First air pump; 35. Second air pump; 36. Air pump nozzle; 37. Hose; 38. Control box; 39. Second controller; 40. Power supply; 41. Through hole; 42. First connecting pipe; 43. Second connecting pipe; 44. Second electrically controlled valve; 45. Third connecting pipe; 46. Second drive motor; 47. Fixing plate; 48. Third cylindrical gear; 49. Top hole; 40. Fixing bracket. Detailed implementation method The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0020] Example 1 like Figures 1-10As shown, an experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions includes: a tank 1, a vertical pipe 23, and a second air pump 34; a support base 2 is fixedly installed at the bottom of the tank 1, an observation window 5 is provided on the front of the tank 1, and a detector 6 is installed on the front of the tank 1; an automatically rotatable disc cover 8 is provided at the top opening of the tank 1, and a piston disc 20 with adjustable height is provided below the disc cover 8. A sealing ring 21 is fixedly fitted on the cylindrical surface of the piston disc 20, and the sealing ring 21 is in close contact with the inner wall of the tank 1; a plurality of through holes 37 are evenly opened on the disc surface of the piston disc 20, the vertical pipe 23 passes through the through holes 37, and the top end of the vertical pipe 23 is fixedly connected to the bottom of the disc cover 8. A corrugated flexible sleeve 22 is fitted on the vertical pipe 23, the top end of the corrugated flexible sleeve 22 is fixedly connected to the bottom of the disc cover 8, and the bottom end of the corrugated flexible sleeve 22 is... The top of the piston disc 20 is fixedly connected, and the bottom end of the corrugated flexible sleeve 22 is connected to the through hole 37; the lower part of the vertical tube 23 has multiple fine holes 24 evenly spaced along its length, and the bottom end of the vertical tube 23 is closed; a second air pump 34 is fixedly installed on the top of the piston disc 20, the air inlet 3401 of the second air pump 34 passes through the piston disc 20, and the bottom end of the air inlet 3401 of the second air pump 34 is located below the piston disc 20; a flexible hose 35 is connected to the air outlet of the second air pump 34, and the flexible hose 35 is connected to the cavity 801 set inside the disc cover 8; the top end of the vertical tube 23 is also connected to the cavity 801 inside the disc cover 8; an inlet / outlet valve 3 and a vent valve 4 are installed on one side of the tank body 1, and an air inlet valve 7 is installed on the other side of the tank body 1; a heating plate 27 is installed on the bottom inner wall of the tank body 1; multiple temperature sensors 28 are evenly spaced along the height direction on the inner wall of the tank body 1.

[0021] As a specific solution, the solubility is detected by the detector 6, which facilitates the diffusion and uniform mixing of methane gas into the oil-based drilling fluid. Specifically, the stirring motor 25 at the bottom drives the stirring blades 26 to rotate, which can mix and stir the oil-based drilling fluid. Furthermore, the methane gas is delivered through the second air pump 34, diffused through multiple evenly distributed vertical pipes 23, and discharged into the oil-based drilling fluid through the fine holes 24. The even distribution of these pipes facilitates diffusion into the oil-based drilling fluid. Furthermore, when methane is introduced into the oil-based drilling fluid, the disc cover 8 can be driven to rotate, and the structure under the disc cover 8 will also rotate along with it, so that multiple vertical pipes 23 move in a circular motion together, thereby ensuring that the vertical pipes 23 uniformly provide methane gas into the oil-based drilling fluid. Through the above, the dissolution rate of methane gas in the oil-based drilling fluid is greatly improved, which facilitates the overall experimental speed, saves experimental time, and has a good overall effect.

[0022] Example 2 like Figure 2 As shown, in a specific embodiment, a stirring motor 25 is installed at the bottom of the tank 1. Multiple fixing brackets 46 are evenly fixedly installed on the outer wall of the housing of the stirring motor 25. The fixing brackets 46 are fixedly connected to the bottom outer wall of the tank 1. A stirring blade 26 is fixedly installed at the output shaft end of the stirring motor 25, and the stirring blade 26 is located above the bottom inner wall of the tank 1, so that the bottom of the tank 1 has a stirring function. Specifically, the stirring motor 25 drives the stirring blade 26 to rotate, thereby realizing the stirring and mixing of the oil-based drilling fluid inside the tank 1, which facilitates the mixing and stirring of the gas introduced into the oil-based drilling fluid.

[0023] like Figure 2 and Figure 3 As shown, in a specific embodiment, a gear ring 19 is fixedly installed at the bottom of the disc cover 8. A third cylindrical gear 44 is meshed with one side of the outer ring of the gear ring 19. A second drive motor 42 is arranged below the third cylindrical gear 44. The output shaft of the second drive motor 42 is fixedly sleeved with the third cylindrical gear 44. A fixing plate 43 is fixedly installed on the second drive motor 42. The fixing plate 43 is fixedly installed on the inner wall of the top side of the tank body 1. The disc cover 8 is connected to the opening at the top of the tank body 1 with a clearance fit. The third cylindrical gear 44 can be driven to rotate by the second drive motor 42. Through the meshing transmission between the third cylindrical gear 44 and the gear ring 19, the disc cover 8 can be driven to rotate, thereby further causing the structure at the bottom of the disc cover 8 to rotate together. This facilitates the circular motion of the vertical pipe 23, allowing the vertical pipe 23 to be in different positions in the oil-based drilling fluid, providing ventilation to different positions, and improving the uniformity of mixing.

[0024] like Figure 1 and Figure 2 As shown, in a specific embodiment, the disc cover 8 has a mounting hole 18 in the middle, and a rotating nut 11 is connected to the mounting hole 18 with clearance fit. The rotating nut 11 is a rotating body structure, and a screw 13 is threadedly connected to the rotating nut 11. The bottom end of the screw 13 is fixedly connected to the middle of the piston disc 20. Multiple guide rods 10 are fixedly installed on the top surface of the piston disc 20. The guide rods 10 pass through the guide holes 9 on the disc cover 8. A first cylindrical gear 12 is fixedly sleeved on the top of the rotating nut 11. The disc cover 8 has a top hole 45. The first cylindrical gear 12 is meshed with a second cylindrical gear 16. A fixed bracket 14 is fixedly installed on the disc cover 8. A first drive motor 15 is fixedly installed on the fixed bracket 14. The output shaft of the first drive motor 15 is fixedly sleeved with the second cylindrical gear 16. The first drive motor 15 can drive the rotating nut 11 to rotate. With the guiding effect between the guide rods 10 and the guide holes 9, the piston disc 20 can be lifted and lowered.

[0025] like Figure 7 As shown, in a specific embodiment, both the first drive motor 15 and the second drive motor 42 are composed of a housing 1501, a rotating motor 1502, a rotating shaft 1503, a worm gear 1504, and a worm 1505. The rotating motor 1502 is fixedly installed on the outer wall of the housing 1501. The worm 1505 and the rotating shaft 1503 are rotatably installed inside the housing 1501. The worm gear 1504 is fixedly sleeved on the rotating shaft 1503. The worm gear 1504 meshes with the worm 1505. One end of the worm 1505 is fixedly connected to the output shaft end of the rotating motor 1502. The rotating motor 1502 drives the worm 1505 to rotate. Through the meshing transmission between the worm 1505 and the worm gear 1504, the rotating shaft 1503 can be rotated, thereby causing the second cylindrical gear 16 and the third cylindrical gear 44 to rotate.

[0026] like Figure 2 and Figure 4 As shown, in a specific embodiment, a first air pump 33 is fixedly installed on the top of the piston disc 20. A second electrically controlled valve 40 is installed at the air outlet of the first air pump 33. The second electrically controlled valve 40 is connected to a third connecting pipe 41, which communicates with the air chamber inside the sealing ring 21. The air chamber inside the sealing ring 21 is also connected to a first connecting pipe 38 and a second connecting pipe 39. A first electrically controlled valve 32 is installed at one end of the first connecting pipe 38 and is installed on the top of the piston disc 20. A second pressure sensor 31 is installed at one end of the second connecting pipe 39 and is installed on the top of the piston disc 20. The second pressure sensor 31 can provide different levels of air pressure to the sealing ring 21, thereby changing the degree of expansion of the sealing ring 21. This is achieved by providing air through the first air pump 33.

[0027] like Figure 10As shown, a control box 36 and a second wireless module 30 are provided on the top of the piston disc 20. The control box 36 contains a second controller 3601 and a power supply 3602. A first pressure sensor 29 is located at the center of the bottom of the piston disc 20. The second wireless module 30 and the first pressure sensor 29 are both electrically connected to the second controller 3601. The second controller 3601 is also electrically connected to the second pressure sensor 31, the first air pump 33, the second air pump 34, the first electrically controlled valve 32, and the second electrically controlled valve 40. A device is fixedly mounted on one side of the outer wall of the tank body 1. The system is equipped with a control cabinet 17, which contains a first wireless module 1702 and a first controller 1701. The first wireless module 1702 is electrically connected to the first controller 1701, and the first wireless module 1702 is also electrically connected to a second wireless module 30. The first controller 1701 is also electrically connected to a detector 6, a rotating motor 1502, a stirring motor 25, a heating plate 27, and a temperature sensor 28, providing intelligent control for the entire system. Both the first controller 1701 and the second controller 3601 can be single-chip microcomputer controllers to provide overall control.

[0028] As another aspect of this application, a method for testing the solubility of methane in oil-based drilling fluids under high temperature and high pressure conditions is provided, the method comprising the following steps: Step 1: Loading oil-based drilling fluid. Open the inlet / outlet valve 3 and the vent valve 4. Introduce oil-based drilling fluid through the inlet / outlet valve 3 until the tank 1 is filled with oil-based drilling fluid at the position below the vent valve 4. When introducing oil-based drilling fluid, observe through the observation window 5 to determine the fluid level. Then close the inlet / outlet valve 3 and the vent valve 4. Step 2: Methane gas loading. The gas is connected to an external gas supply device through the inlet valve 7. The first drive motor 15 drives the second cylindrical gear 16 to rotate. Through the meshing transmission between the second cylindrical gear 16 and the first cylindrical gear 12, the rotating nut 11 can rotate, causing the rotating nut 11 to turn about the screw 13. With the guidance of the guide rod 10 and the guide hole 9, the piston disc 20 is vertically driven, causing the piston disc 20 to move upward and move to a high position in the tank 1. When the piston disc 20 moves upward, it provides suction for the space in the tank 1 at the bottom of the piston disc 20. Methane is loaded into the tank 1 through the gas supply device, and then the inlet valve 7 is closed. Step 3: Heating and pressurization. Heating is performed by heating plate 27, which raises the internal temperature of tank 1 to create a high-temperature environment. Temperature sensor 28 senses the internal temperature and provides feedback to control cabinet 17 for temperature control. Driven by piston plate 20, piston plate 20 moves downward and pressurizes, increasing the methane gas pressure to create a high-pressure environment. The gas pressure is sensed by first pressure sensor 29 and transmitted to second controller 3601. Second controller 3601 processes the data and transmits the signal wirelessly to control cabinet 17 via second wireless module 30. First wireless module 1702 receives the signal and transmits it to first controller 1701. First controller 1701 controls first drive motor 15 to adjust the pressure and thus control the high pressure and high temperature of the internal environment. Step 4, assisted dissolution: Under specific high pressure and high temperature conditions, the second air pump 34 draws methane gas from the bottom of the piston disc 20, allowing the methane gas to enter the cavity 801 through the hose 35, providing methane gas to the top of the vertical pipe 23. The gas is transported through the vertical pipe 23 and discharged through the fine hole 24 at the bottom of the vertical pipe 23, allowing the gas to enter the oil-based drilling fluid. Through multiple evenly distributed vertical pipes 23, the introduced gas is dispersed to different positions in the oil-based drilling fluid. Step 5: Rotation and mixing. Driven by the stirring motor 25, the stirring blades 26 rotate, stirring the internal oil-based drilling fluid and facilitating the mixing of the introduced gas. Further driven by the second drive motor 42, the third cylindrical gear 44 rotates. Through the meshing transmission between the third cylindrical gear 44 and the gear ring 19, the disc cover 8 rotates, and the structure below the disc cover 8 also rotates, including the piston disc 20. During rotation, the second air pump 34 continuously supplies air, so that the vertical pipe 23 continuously outputs air during its circular motion, which can further improve the effect of dispersing the introduced gas into the oil-based drilling fluid and facilitate dissolution. Step 6: Measurement. After dissolution, the methane in the oil-based drilling fluid is measured using detector 6 to complete the experiment.

[0029] The experimental apparatus and method for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions proposed in this application can provide different high temperature and high pressure environments. Solubility is detected by a detector 6. Compared with traditional techniques, this method facilitates the diffusion and uniform mixing of methane gas into the oil-based drilling fluid. Specifically, a bottom-mounted stirring motor 25 drives the stirring blades 26 to rotate, enabling internal mixing and stirring of the oil-based drilling fluid. Furthermore, a second air pump 34 delivers methane gas, which diffuses through multiple evenly distributed vertical pipes 23 and enters through fine holes 24. In the discharged oil-based drilling fluid, the methane gas is evenly distributed in multiple components, facilitating diffusion into the oil-based drilling fluid. Furthermore, when methane is introduced into the oil-based drilling fluid, the disc cover 8 can be driven to rotate, and the structure below the disc cover 8 will also rotate along with it, causing multiple vertical pipes 23 to move in a circular motion together. This ensures that the vertical pipes 23 uniformly supply methane gas to the oil-based drilling fluid. Through the above, the dissolution rate of methane gas in the oil-based drilling fluid is greatly improved, which facilitates the improvement of the overall experimental speed, saves experimental time, and has a good overall effect.

[0030] Finally, it should be noted that the above embodiments are only for illustration and not for limiting the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An experimental apparatus for testing the solubility of methane in oil-based drilling fluids under high temperature and high pressure conditions, characterized in that: The system includes a tank (1), a vertical pipe (23), and a second air pump (34); wherein, a support base (2) is fixedly installed at the bottom of the tank (1), an observation window (5) is provided on the front of the tank (1), and a detector (6) is installed on the front of the tank (1); an automatically rotatable disc cover (8) is provided at the top opening of the tank (1), and a height-adjustable piston disc (20) is provided below the disc cover (8), and a sealing ring (2) is fixedly fitted on the cylindrical surface of the piston disc (20). 1), and the sealing ring (21) is in close contact with the inner wall of the tank (1); several through holes (37) are evenly opened on the surface of the piston disc (20), the vertical tube (23) passes through the through holes (37), and the top end of the vertical tube (23) is fixedly connected to the bottom of the disc cover (8), a corrugated soft sleeve (22) is sleeved on the vertical tube (23), the top end of the corrugated soft sleeve (22) is fixedly connected to the bottom of the disc cover (8), and the bottom end of the corrugated soft sleeve (22) is fixedly connected to the top of the piston disc (20). The bottom end of the corrugated flexible sleeve (22) is connected to the through hole (37); the lower part of the vertical tube (23) is provided with a plurality of fine holes (24) at equal intervals along the length direction, and the bottom end of the vertical tube (23) is closed; a second air pump (34) is fixedly installed on the top of the piston disc (20), the air inlet of the second air pump (34) passes through the piston disc (20), and the bottom end of the air inlet of the second air pump (34) is located below the piston disc (20), and a flexible hose (35) is connected to the air outlet of the second air pump (34). The hose (35) is connected to the cavity (801) inside the disc cover (8), and the top of the vertical tube (23) is also connected to the cavity (801) inside the disc cover (8); an inlet / outlet valve (3) and a vent valve (4) are installed on one side of the tank (1), and an air inlet valve (7) is installed on the other side of the tank (1); a heating plate (27) is installed on the bottom inner wall of the tank (1); and multiple temperature sensors (28) are installed at equal intervals along the height direction on the inner wall of the tank (1).

2. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 1, characterized in that: The bottom of the tank (1) is provided with a stirring motor (25). Multiple fixing brackets (46) are evenly fixed on the outer wall of the casing of the stirring motor (25). The fixing brackets (46) are fixedly connected to the bottom outer wall of the tank (1). The output shaft end of the stirring motor (25) is fixedly installed with stirring blades (26), and the stirring blades (26) are located above the bottom inner wall of the tank (1).

3. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 2, characterized in that: A gear ring (19) is fixedly installed at the bottom of the disc cover (8). A third cylindrical gear (44) is meshed on one side of the outer ring of the gear ring (19). A second drive motor (42) is provided below the third cylindrical gear (44). The output shaft of the second drive motor (42) is fixedly sleeved with the third cylindrical gear (44). A fixing plate (43) is fixedly installed on the second drive motor (42). The fixing plate (43) is fixedly installed on the inner wall of the top side of the tank body (1). The disc cover (8) is connected to the opening at the top of the tank body (1) with a clearance fit.

4. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 3, characterized in that: The disc cover (8) has a mounting hole (18) in the middle, and a rotating nut (11) is connected to the mounting hole (18) with clearance fit. The rotating nut (11) is a rotating body structure. The rotating nut (11) is threadedly connected to a screw (13). The bottom end of the screw (13) is fixedly connected to the middle of the piston disc (20). Multiple guide rods (10) are fixedly installed on the top surface of the piston disc (20). The guide rods (10) pass through the guide holes (9) on the disc cover (8). The top end of the rotating nut (11) is fixedly sleeved with a first cylindrical gear (12). The disc cover (8) has a top hole (45).

5. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 4, characterized in that: The first cylindrical gear (12) is meshed with the second cylindrical gear (16). A fixed bracket (14) is fixedly installed on the disc cover (8). A first drive motor (15) is fixedly installed on the fixed bracket (14). The output shaft of the first drive motor (15) is fixedly sleeved with the second cylindrical gear (16).

6. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 5, characterized in that: The first drive motor (15) and the second drive motor (42) are both composed of a housing (1501), a rotating motor (1502), a rotating shaft (1503), a worm gear (1504), and a worm (1505). The rotating motor (1502) is fixedly installed on the outer wall of the housing (1501). The worm (1505) and the rotating shaft (1503) are rotatably installed inside the housing (1501). The worm gear (1504) is fixedly sleeved on the rotating shaft (1503). The worm gear (1504) is meshed with the worm (1505). One end of the worm (1505) is fixedly connected to the output shaft end of the rotating motor (1502).

7. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 6, characterized in that: A first air pump (33) is fixedly installed on the top of the piston disc (20). A second electrically controlled valve (40) is installed at the outlet end of the first air pump (33). The second electrically controlled valve (40) is connected to a third connecting pipe (41). The third connecting pipe (41) is connected to the air chamber inside the sealing ring (21). The air chamber inside the sealing ring (21) is also connected to a first connecting pipe (38) and a second connecting pipe (39). A first electrically controlled valve (32) is installed at one end of the first connecting pipe (38), and the first electrically controlled valve (32) is installed on the top of the piston disc (20). A second pressure sensor (31) is installed at one end of the second connecting pipe (39), and the second pressure sensor (31) is installed on the top of the piston disc (20).

8. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 7, characterized in that: The piston disc (20) is provided with a control box (36) and a second wireless module (30) on its top. The control box (36) is provided with a second controller (3601) and a power supply (3602). The piston disc (20) is provided with a first pressure sensor (29) at its bottom center. The second wireless module (30) and the first pressure sensor (29) are both electrically connected to the second controller (3601). The second controller (3601) is also electrically connected to the first air pump (33), the second air pump (34), the first electrically controlled valve (32), and the second electrically controlled valve (40).

9. The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions according to claim 8, characterized in that: A control cabinet (17) is fixedly installed on one side of the outer wall of the tank (1). The control cabinet (17) is equipped with a first wireless module (1702) and a first controller (1701). The first wireless module (1702) is electrically connected to the first controller (1701), and the first wireless module (1702) is electrically connected to the second wireless module (30). The first controller (1701) is also electrically connected to the detector (6), the rotating motor (1502), the stirring motor (25), the heating plate (27), and the temperature sensor (28).

10. A method for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions, characterized in that, The experimental apparatus for testing the solubility of methane in oil-based drilling fluid under high temperature and high pressure conditions as described in claim 9 includes the following steps: Step 1: Loading oil-based drilling fluid. Open the inlet / outlet valve (3) and the vent valve (4). Introduce oil-based drilling fluid through the inlet / outlet valve (3) so that the tank (1) is filled with oil-based drilling fluid at the lower position of the vent valve (4). When introducing oil-based drilling fluid, observe through the observation window (5) to determine the fluid level. Then close the inlet / outlet valve (3) and the vent valve (4). Step 2: Methane gas is loaded. The gas supply equipment is connected to the external gas supply equipment through the gas inlet valve (7). The second cylindrical gear (16) is driven to rotate by the first drive motor (15). Through the meshing transmission between the second cylindrical gear (16) and the first cylindrical gear (12), the rotating nut (11) can rotate, so that the rotating nut (11) is turned about the screw (13). With the guidance of the guide rod (10) and the guide hole (9), the piston disc (20) is vertically driven, so that the piston disc (20) moves upward and moves to the high position in the tank (1). When the piston disc (20) moves upward, it provides suction for the space in the tank (1) at the bottom of the piston disc (20). Methane is loaded into the tank (1) through the gas supply equipment, and then the gas inlet valve (7) is closed. Step 3: Heating and pressurization. Heating is performed by heating plate (27) to raise the internal temperature of tank (1) and create a high-temperature environment. The internal temperature is sensed by temperature sensor (28) and feedback is provided to control cabinet (17) to control the temperature. The piston plate (20) is driven to move downward and pressurize by piston plate (20) to increase the pressure of methane gas and create a high-pressure environment. The gas pressure is sensed by first pressure sensor (29) and transmitted to second controller (3601). The second controller (3601) processes the signal and transmits it to control cabinet (17) in the form of wireless signal through second wireless module (30). The signal is received by first wireless module (1702) and transmitted to first controller (1701). The first controller (1701) controls the first drive motor (15) to adjust the pressure and thus control the high pressure and high temperature of the internal environment. Step 4, assisted dissolution, under specific high pressure and high temperature environment, the second air pump (34) draws the methane gas from the bottom of the piston disc (20), so that the methane gas enters the cavity (801) through the hose (35) to provide methane gas to the top of the vertical pipe (23). The gas is transported through the vertical pipe (23) and discharged through the fine hole (24) at the bottom of the vertical pipe (23), so that the gas is introduced into the oil-based drilling fluid. Through multiple evenly distributed vertical pipes (23), the introduced gas is dispersed and dispersed to different positions in the oil-based drilling fluid; Step 5: Rotation and mixing. Driven by the stirring motor (25), the stirring blades (26) rotate. The stirring blades (26) stir the internal oil-based drilling fluid, which facilitates the mixing of the introduced gas. The second drive motor (42) provides drive, which makes the third cylindrical gear (44) rotate. Through the meshing transmission between the third cylindrical gear (44) and the gear ring (19), the disc cover (8) rotates. The structure below the disc cover (8) also rotates along with it, including the piston disc (20). When rotating, the second air pump (34) continuously vents air, so that when the vertical pipe (23) moves in a circle, it continuously vents air, which can further improve the effect of dispersing the introduced gas into the oil-based drilling fluid and facilitate dissolution. Step 6: Measurement. After dissolution, the methane in the oil-based drilling fluid is measured using a detector (6) to complete the experiment.

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