A sulfonate drilling fluid plugging test system

Abstract

The present application relates to a kind of sulfonate drilling fluid plugging test system.Sulfonate drilling fluid plugging test system includes: outer tube, with small diameter section and large diameter section, the pipe wall of large diameter section is provided with mesh hole;Shale, annular structure, and inside large diameter section, shale has crack, the position of crack corresponds with mesh hole, the inner cavity of small diameter section and the inner cavity of shale are through, to form placement cavity;Inner tube, including cavity section and cavity section, cavity section with small diameter section, shale encloses annular return liquid chamber;Liquid outlet storage tank, through liquid outlet pipeline with cavity section is communicated;Liquid return storage tank, through liquid return pipeline with annular return liquid chamber is communicated;Drive pump, set on liquid outlet pipeline or liquid return pipeline;Shell, sleeve is set on large diameter section, shell with large diameter section encloses leakage chamber, mesh hole and leakage chamber are communicated;Air source, for pressurizing in leakage chamber;Pressure measurement component, for measuring the pressure difference in annular return liquid chamber and leakage chamber;Heating box, inner tube, outer tube and leakage chamber are arranged in heating box.

Description

Technical Field

[0001] This invention relates to drilling fluid plugging test systems, specifically to a sulfonate drilling fluid plugging test system. Background Technology

[0002] During normal drilling, due to factors such as pressure difference, temperature difference, chemical difference, and formation capillary pressure between ordinary drilling fluid and formation pore fluid, ordinary drilling fluid enters the near-wellbore formation, thereby increasing formation collapse pressure and reducing formation rock strength.

[0003] To address the aforementioned issues, existing technologies utilize sulfonate drilling fluids instead of ordinary drilling fluids. For example, sulfonated asphalt is produced by sulfonating, neutralizing, and post-processing asphalt under specific conditions. When drilling with drilling fluid containing sulfonated asphalt, the temperature reaches near the asphalt's softening point. Under high temperature and pressure, the asphalt softens and becomes viscous, interacting with clay particles to form a dense mud cake. This mud cake effectively seals fractures, preventing the solid and liquid phases of the drilling fluid from invading the formation, thus protecting the wellbore from collapse and protecting the oil and gas reservoir.

[0004] However, in the process of using sulfonate drilling fluids, the degree of sulfonation directly affects the basic properties of the fluid, which in turn affects the overall effectiveness of plugging and collapse prevention, and ultimately determines the success of fracture sealing. Therefore, it is necessary to clarify the effects of different sulfonate drilling fluids on shale plugging. Summary of the Invention

[0005] The purpose of this invention is to provide a sulfonate drilling fluid plugging test system for testing the effect of sulfonate drilling fluids with different degrees of sulfonation on plugging fractures.

[0006] To achieve the above objectives, the technical solution of the sulfonate drilling fluid plugging test system of the present invention is as follows:

[0007] The sulfonate drilling fluid plugging test system includes an outer tube and an inner tube. The outer tube has a small-diameter section and a large-diameter section, with the small-diameter section located above the large-diameter section. The wall of the large-diameter section is perforated, and both ends of the outer tube are closed. The interior of the large-diameter section contains annular shale with fractures, the positions of which correspond to the perforations. The inner cavity of the small-diameter section and the inner cavity of the shale are interconnected to form a placement cavity. The inner tube includes an inner cavity section within the placement cavity and an outer cavity section outside the placement cavity. The inner cavity section, together with the small-diameter section and the shale, forms an annular return fluid cavity. The outer section is connected to an outlet storage tank via an outlet pipe, and the annular return liquid chamber is connected to a return liquid storage tank via a return liquid pipe. A drive pump is installed on the outlet or return liquid pipe. An outer shell is fitted onto the large-diameter section, and the outer shell and the large-diameter section form a seepage chamber, with the mesh communicating with the seepage chamber. The seepage chamber is connected to a gas source via a pressure pipe, and the gas source is used to pressurize the seepage chamber. It also includes a heating box and a pressure measuring component, which is used to measure the pressure difference between the annular return liquid chamber and the seepage chamber. The inner pipe, outer pipe, and seepage chamber are set inside the heating box.

[0008] The beneficial effects are: under the simulated high temperature and high pressure environment of the formation by the gas source and heating box, sulfonate drilling fluid seeps out from the cracks in the shale and flows out to the seepage chamber through the mesh on the pipe wall of the large diameter section. By comparing the amount of drilling fluid flowing into the seepage chamber with different degrees of sulfonation of sulfonate drilling fluid during the test, the effect of sulfonated asphalt drilling fluid with different degrees of sulfonation on shale plugging can be obtained.

[0009] As a further improvement, the sulfonate drilling fluid plugging test system also includes a waste liquid recovery tank. The bottom of the leakage chamber is equipped with a leakage outlet, and the waste liquid recovery tank is used to recover the waste liquid flowing out of the leakage outlet.

[0010] The beneficial effect is that a permeate outlet is set at the bottom of the leakage chamber, which facilitates the recycling of waste liquid.

[0011] As a further improvement, the waste liquid recovery tank is connected to the leakage outlet via a recovery pipeline.

[0012] The beneficial effect is that by setting up a recycling pipeline, the waste liquid recycling tank can be placed outside the heating box, which helps to reduce the size of the heating box.

[0013] As a further improvement, the pressure measurement assembly includes a display and two pressure sensors, which are respectively mounted on the small diameter section and the housing, and are connected to the display.

[0014] The beneficial effect is that the display directly shows the pressure difference between the annular return chamber and the leakage chamber, which can obtain the pressure difference result more accurately and quickly.

[0015] As a further improvement, the outlet storage tank and the return storage tank are the same tank.

[0016] The beneficial effect is that the drilling fluid in the return fluid storage tank can be recycled, saving resources.

[0017] As a further improvement, a nozzle is provided at the outlet of the cavity section.

[0018] The beneficial effect is that the nozzle allows the drilling fluid under high pressure to be sprayed more evenly into the annular return chamber.

[0019] As a further improvement, the outer surface of the shale is covered with a ring-shaped mesh.

[0020] The beneficial effects are: the ring mesh fixes the shale inside the large-diameter section and ensures the stability of the shale during the test.

[0021] As a further improvement, the outer shell is transparent.

[0022] The beneficial effect is that the transparent shell makes it easy to observe and record the process and amount of drilling fluid flowing out into the seepage chamber.

[0023] As a further improvement, both the inner and outer tubes are transparent.

[0024] The beneficial effects are: it facilitates the observation of the process of drilling fluid flowing out of the shale fractures, and at the same time, it facilitates the control of the test process and the detection of anomalies.

[0025] As a further improvement, an observation window is provided on the heating chamber.

[0026] The beneficial effect is that during the experiment, the entire process and results can be observed and recorded using the observation window, avoiding the burden of removing the outer shell, outer tube, inner tube and other test equipment. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the sulfonate drilling fluid plugging test system of the present invention;

[0028] Figure 2 for Figure 1 An exterior view of the assembled outer shell, outer tube, and inner tube;

[0029] In the diagram: 11. Drilling fluid storage tank; 12. Drive pump; 13. Flow meter; 14. Discharge valve; 15. Heating box; 16. Blind flange; 17. Outer pipe; 18. Nozzle; 19. Inner pipe; 20. Shale; 21. Crack; 22. Outer shell; 23. Leakage chamber; 24. Ring mesh; 25. Booster pump; 26. Display; 27. Waste liquid recovery tank; 28. Recovery valve; 29. ​​Annular return fluid chamber; 30. Return fluid port; 31. Pressure sensor; 32. Leakage fluid outlet; 33. Gas inlet; 34. Return fluid valve; 35. Air inlet valve. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0032] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Additionally, the terms "front," "rear," "upper," "lower," "left," and "right" are based on the orientation and positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention, not to indicate that the referred device or component must have a specific orientation, and therefore should not be construed as limiting the invention.

[0033] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0034] Example 1 of the sulfonate drilling fluid plugging test system of the present invention:

[0035] In this embodiment, as Figure 1 and Figure 2 As shown, the sulfonate drilling fluid plugging test system includes an outer pipe 17, a shale 20, an inner pipe 19, a drilling fluid storage tank 11, an outer shell 22, a pressurizing pump 25, a pressure measuring component, a waste fluid recovery tank 27, and a heating box 15.

[0036] In this embodiment, the outer tube 17 is a transparent tube with a small diameter section and a large diameter section. The small diameter section is located above the large diameter section, and the tube wall of the large diameter section is provided with mesh. Both ends of the outer tube 17 are closed structures. The upper end of the small diameter section is closed with a blind plate 16, and the lower end of the large diameter section is closed with a cover plate. A return port 30 is provided below the closed end of the small diameter section.

[0037] In this embodiment, the shale 20 was obtained from on-site sampling. The shale 20 has a ring-shaped structure, with its outer surface covered by a ring-shaped mesh 24, which fixes the shale 20 inside the large-diameter section. The shale 20 also has several cracks 21 with an average width of approximately 1 mm, the positions of which correspond to the mesh openings on the pipe wall of the large-diameter section. Simultaneously, the inner cavity of the shale 20 is connected to the inner cavity of the small-diameter section to form a placement cavity.

[0038] In this embodiment, the inner tube 19 is a transparent tube that passes through the blind plate 16. The inner tube 19 includes an inner section inside the placement cavity and an outer section outside the placement cavity. The area enclosed by the inner section, the small-diameter section, and the shale 20 is an annular return fluid cavity 29. A nozzle 18 is provided at the outlet of the inner section.

[0039] In this embodiment, the outlet tank and the return tank are the same tank, namely the drilling fluid storage tank 11. The drilling fluid storage tank 11 is connected to the inlet of the outer section of the cavity through the outlet pipeline, and then to the inner pipe 19. The outlet pipeline is sequentially connected to the drive pump 12, the flow meter 13, and the outlet valve 14. At the same time, the drilling fluid storage tank 11 is connected to the return port 30 through the return pipeline, and then to the annular return cavity 29. The return pipeline is equipped with a return valve 34.

[0040] In this embodiment, the outer shell 22 is a transparent shell, which is fitted onto the large-diameter section of the outer pipe 17. The outer shell 22 and the large-diameter section form a seepage chamber 23. The mesh on the pipe wall of the large-diameter section is connected to the seepage chamber 23 to ensure that the drilling fluid can seep out from the crack 21 of the shale 20 and enter the seepage chamber 23.

[0041] In this embodiment, the outer casing 22 is provided with two gas inlets 33 spaced apart circumferentially along the outer pipe 17. The pressurization pump 25 is connected to the gas inlets 33 through a pressure pipeline, thereby pressurizing the seepage chamber 23 to simulate the high-pressure environment in the formation. An air inlet valve 35 is provided on the pressure pipeline. The pressurization pump 25 is the gas source.

[0042] In this embodiment, two leakage outlets 32 are radially spaced at the bottom of the outer casing 22. The waste liquid recovery tank 27 is connected to the leakage outlets 32 via a recovery pipeline to recover the waste liquid flowing out of the leakage chamber 23. A recovery valve 28 is installed on the recovery pipeline to control the opening and closing of the recovery pipeline. The wall of the waste liquid recovery tank 27 is engraved with graduations to record the amount of waste liquid flowing into the waste liquid recovery tank 27 in each test.

[0043] In this embodiment, the pressure measurement assembly includes a display 26 and two pressure sensors 31. One pressure sensor 31 is connected to the small-diameter section of the outer tube 17 to measure the pressure within the annular return chamber 29, and the other pressure sensor 31 is connected to the housing 22 to measure the pressure within the leakage chamber 23. The display 26 is connected to the two pressure sensors 31 to receive pressure information from the annular return chamber 29 and the leakage chamber 23, and then calculates and displays the pressure difference between the annular return chamber 29 and the leakage chamber 23. In this embodiment, the display 26 is a computer.

[0044] In this embodiment, the inner tube 19, outer tube 17, and outer shell 22 are arranged inside the heating chamber 15. The heating chamber 15 brings the test environment to the formation temperature to more realistically simulate the working environment of drilling fluid in the formation. At the same time, the heating chamber 15 is equipped with an observation window, so that the leakage situation inside the leakage chamber 23 can be photographed through the observation window.

[0045] When the sulfonate drilling fluid plugging test system is running, the heating box 15 operates, and conventional drilling fluid is poured into the drilling fluid storage tank 11. Then, the drive pump 12, the outlet valve 14, the return valve 34, the air inlet valve 35, and the pressure pump 25 are opened in sequence, and the recovery valve 28 is closed. By adjusting the pump pressure of the drive pump 12 and the pressure pump 25, the pressure difference between the annular return chamber 29 and the leakage chamber 23 displayed on the monitor 26 is kept within 0.05 MPa.

[0046] Through the observation window on the heating box 15, it can be seen that conventional drilling fluid enters the inner pipe 19 through the outlet pipe and is then sprayed out into the annular return chamber 29 through the nozzle 18. A portion of the conventional drilling fluid flows out from the return port 30 under pressure and returns to the drilling fluid storage tank 11 through the return pipe. Another portion seeps out through the cracks 21 in the shale 20 and flows through the mesh of the large-diameter section of the outer pipe 17 into the seepage chamber 23. After a set time, the drive pump 12, outlet valve 14, pressurization pump 25, and air inlet valve 35 are closed, and the recovery valve 28 is opened to discharge the drilling fluid in the seepage chamber 23 into the waste fluid recovery tank 27. The amount of waste fluid flowing into the waste fluid recovery tank 27 is recorded.

[0047] Next, close the recovery valve 28 and open the drive pump 12, outlet valve 14, pressurization pump 25, and air inlet valve 35. Add sulfonated asphalt to the conventional drilling fluid in the drilling fluid storage tank 11 to form sulfonated asphalt drilling fluid. The sulfonation degree of the sulfonated asphalt drilling fluid is adjusted to 6%, and the sulfonated asphalt drilling fluid belongs to the sulfonate drilling fluid category. Adjust the drive pump 12, pressurization pump 25, and heating chamber 15 to ensure the same test temperature and pressure as the conventional drilling fluid for the test. After the same time, close the drive pump 12 and outlet valve 14, as well as the pressurization pump 25 and air inlet valve 35. Open the recovery valve 28 to discharge the drilling fluid in the seepage chamber 23 into the waste fluid recovery tank 27, and record the amount of waste fluid flowing into the waste fluid recovery tank 27.

[0048] Next, close the recovery valve 28 and open the drive pump 12, the outlet valve 14, the pressurization pump 25, and the air inlet valve 35. Continue to add sulfonated asphalt to the drilling fluid storage tank 11, and prepare the sulfonated asphalt drilling fluid with sulfonation degrees of 10%, 14%, and 18%, respectively. Repeat the above steps, and after the same amount of time, record the amount of waste fluid flowing into the waste fluid recovery tank 27 during the tests of sulfonated asphalt drilling fluid with different sulfonation degrees.

[0049] In this embodiment, by comparing the amount of waste liquid flowing into the waste liquid recovery tank 27 during the test of sulfonated asphalt drilling fluid with different degrees of sulfonation, the effect of sulfonated asphalt drilling fluid with different degrees of sulfonation on the sealing of shale 20 can be clearly obtained.

[0050] Example 2 of the sulfonate drilling fluid plugging test system of the present invention:

[0051] The difference between this embodiment and Embodiment 1 is that in Embodiment 1, the waste liquid recovery tank 27 is connected to the leachate outlet 32 ​​via a recovery pipeline to recover the waste liquid flowing out of the leachate outlet 32. In this embodiment, no recovery pipeline is provided, and the waste liquid recovery tank is placed below the leachate outlet to recover the waste liquid flowing out of the leachate outlet.

[0052] Example 3 of the sulfonate drilling fluid plugging test system of the present invention:

[0053] The difference between this embodiment and Embodiment 1 is as follows: In Embodiment 1, the pressure measurement component includes a display 26 and two pressure sensors 31, which are respectively disposed on the small diameter section and the housing 22, and are connected to the display 26. In this embodiment, the pressure measurement component consists of two pressure gauges, which are respectively disposed on the small diameter section and the housing. The pressure in the annular return chamber and the leakage chamber is obtained by reading the data from the pressure gauges, thereby obtaining the pressure difference between the annular return chamber and the leakage chamber.

[0054] Example 4 of the sulfonate drilling fluid plugging test system of the present invention:

[0055] The difference between this embodiment and Embodiment 1 is that in Embodiment 1, the output fluid storage tank and the return fluid storage tank are the same tank, which allows for circulation and avoids drilling fluid waste. In this embodiment, the output fluid storage tank and the return fluid storage tank are two independent tanks. In this case, after a certain amount of drilling fluid is stored in the return fluid storage tank, the drilling fluid can be manually poured into the output fluid storage tank to avoid waste.

[0056] Example 5 of the sulfonate drilling fluid plugging test system of the present invention:

[0057] The difference between this embodiment and Embodiment 1 is that in Embodiment 1, the bottom of the leakage chamber 23 is provided with a leakage outlet 32, and the waste liquid recovery tank 27 is used to recover the waste liquid flowing out of the leakage outlet 32. In this embodiment, the top of the leakage chamber is provided with a leakage outlet. When it is necessary to discharge the waste liquid in the leakage chamber, the inner pipe, outer pipe and outer shell assembled together are flipped over to allow the waste liquid to be poured out from the leakage outlet.

[0058] Example 6 of the sulfonate drilling fluid plugging test system of the present invention:

[0059] The difference between this embodiment and Embodiment 1 is as follows: In Embodiment 1, the outer shell 22 is transparent, the heating chamber 15 is equipped with an observation window, and the waste liquid recovery tank 27 is connected to the leakage outlet 32 ​​through a recovery pipeline to recover the waste liquid flowing out of the leakage outlet 32. This design allows for both filming the test process through the observation window and obtaining the amount of waste liquid for each test through the waste liquid recovery tank 27. In this embodiment, based on the transparent outer shell and the observation window on the heating chamber, the waste liquid recovery tank is not marked, but the outer shell is marked. This design allows for both filming the test process through the observation window and observing the amount of waste liquid in the leakage chamber for each test through the observation window. In this case, if the waste liquid in the leakage chamber does not block the crack, multiple tests can be conducted before draining the waste liquid from the leakage chamber.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A sulfonate drilling fluid plugging test system, characterized in that, The system includes an outer tube (17) and an inner tube (19). The outer tube (17) has a small-diameter section and a large-diameter section. The small-diameter section is located above the large-diameter section. The wall of the large-diameter section is provided with a mesh. Both ends of the outer tube (17) are closed structures. The interior of the large-diameter section is provided with annular shale (20). The shale (20) has cracks (21). The position of the cracks (21) corresponds to the mesh. The inner cavity of the small-diameter section and the inner cavity of the shale (20) are connected to form a placement cavity. The inner tube (19) includes an inner cavity section inside the placement cavity and an outer cavity section outside the placement cavity. The inner cavity section, the small-diameter section, and the shale (20) form an annular return liquid cavity (29). The outer cavity section is connected to a liquid outlet pipe. The liquid outlet storage tank is connected to the return liquid storage tank via the return liquid pipeline (29). A drive pump (12) is installed on the liquid outlet pipeline or the return liquid pipeline. An outer shell (22) is fitted on the large diameter section, and the outer shell (22) and the large diameter section form a leakage chamber (23). The mesh is connected to the leakage chamber (23). The leakage chamber (23) is connected to a gas source via a pressure pipeline. The gas source is used to pressurize the leakage chamber (23). The tank also includes a heating box (15) and a pressure measuring component. The pressure measuring component is used to measure the pressure difference between the annular return liquid chamber (29) and the leakage chamber (23). The inner tube (19), the outer tube (17) and the leakage chamber (23) are installed in the heating box (15).

2. The sulfonate drilling fluid plugging test system according to claim 1, characterized in that, It also includes a waste liquid recovery tank (27), and the bottom of the leakage chamber (23) is provided with a leakage outlet (32). The waste liquid recovery tank (27) is used to recover the waste liquid flowing out of the leakage outlet (32).

3. The sulfonate drilling fluid plugging test system according to claim 2, characterized in that, The waste liquid recovery tank (27) is connected to the leakage outlet (32) through a recovery pipeline.

4. The sulfonate drilling fluid plugging test system according to claim 1, 2, or 3, characterized in that, The pressure measurement assembly includes a display (26) and two pressure sensors (31), which are respectively disposed on the small diameter section and the housing (22), and are connected to the display (26).

5. The sulfonate drilling fluid plugging test system according to claim 1, 2, or 3, characterized in that, The outlet storage tank and the return storage tank are the same tank.

6. The sulfonate drilling fluid plugging test system according to claim 1, 2, or 3, characterized in that, A nozzle (18) is provided at the outlet of the cavity section.

7. The sulfonate drilling fluid plugging test system according to claim 1, 2, or 3, characterized in that, The outer surface of the shale (20) is covered with a ring-shaped mesh (24).

8. The sulfonate drilling fluid plugging test system according to claim 1, 2, or 3, characterized in that, The outer shell (22) is a transparent shell.

9. The sulfonate drilling fluid plugging test system according to claim 8, characterized in that, The inner tube (19) and the outer tube (17) are transparent tubes.

10. The sulfonate drilling fluid plugging test system according to claim 8, characterized in that, The heating box (15) is equipped with an observation window.

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