Silicate water-based drilling fluid special for coal-bed gas well and processing method and device thereof

Abstract

The invention belongs to the technical field of drilling fluid processing, and particularly relates to a special silicate water-based drilling fluid for a coal-bed gas well as well as a processing method and a processing device of the special silicate water-based drilling fluid. The top end of the stirring tank is communicated with a first feeding hole and a second feeding hole, and the bottom end of the stirring tank is communicated with a discharging pipe; a rotating shaft is rotationally connected to the top surface of the inner wall of the stirring tank, and a sliding groove is formed in the bottom surface of the rotating shaft; a rotating shaft is driven by a first motor to rotate, and the rotating shaft drives a connecting shaft to rotate, so that fresh water and additives in a stirring tank are stirred and mixed by stirring blades, and a first screw rod can be driven by the first motor to positively and negatively rotate in a reciprocating manner in the mixing process; the first screw rod drives the connecting shaft to move up and down in the sliding groove, so that the stirring blades move up and down, the stirring blades stir and mix the water and the additive while moving, and the mixing efficiency and uniformity of the additive and the water are improved.

Description

Technical Field

[0001] This invention belongs to the field of drilling fluid processing technology, specifically to a special silicate water-based drilling fluid for coalbed methane wells and its processing method and apparatus. Background Technology

[0002] Coalbed methane wells are unconventional natural gas extraction wells that use coal seams as reservoirs. They are characterized by low pressure, low permeability, and susceptibility to damage, placing stringent requirements on drilling fluid performance. As the core working fluid in drilling operations, drilling fluid must stabilize the wellbore, carry cuttings, and balance formation pressure. Considering the characteristics of coal seams, silicate-based water-based drilling fluids form a tight-fitting plugging layer through the cementation of silicates and clay minerals, effectively reducing filtration loss and inhibiting water-sensitive swelling. Combining environmental friendliness and economic efficiency, this has become an important technical choice for coalbed methane well drilling fluids.

[0003] During the processing of drilling fluid, various additives (such as viscosity improvers, filtration reducers, weighting materials, etc.) are required. A mixer is needed to evenly disperse the additives in the base fluid to form a stable drilling fluid system.

[0004] However, the above-mentioned technologies often have the following drawbacks: When mixing additives and base fluids, traditional drilling fluid mixers typically use a fixed stirring blade in a single position for rotational mixing. This static mixing method has obvious limitations. Because the stirring blades cannot achieve vertical displacement or multi-layer dynamic mixing, the mixing area is limited, and dead zones are easily formed in the tank. Especially when processing high-density or high-viscosity drilling fluids, the fixed-position stirring blades make it difficult to achieve sufficient convection and uniform dispersion of materials, affecting the effective dissolution and suspension of additives. This mixing method not only reduces mixing efficiency but may also lead to uneven local concentrations, thereby affecting the overall performance stability of the drilling fluid. Therefore, this invention provides a silicate water-based drilling fluid for coalbed methane wells, as well as its processing method and apparatus. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by the present invention to solve its technical problem is as follows: The special silicate water-based drilling fluid processing device for coalbed methane wells of the present invention includes a mixing tank; the top of the mixing tank is connected to a first feed inlet and a second feed inlet, and the bottom of the mixing tank is connected to a discharge pipe; a rotating shaft is rotatably connected to the top surface of the inner wall of the mixing tank, a sliding groove is opened on the bottom surface of the rotating shaft, a connecting shaft is slidably connected to the inner wall of the sliding groove, and multiple sets of stirring blades are fixedly connected to the surface of the connecting shaft; a cavity communicating with the sliding groove is opened inside the rotating shaft, a first motor for driving the rotating shaft to rotate is fixedly connected to the top surface of the mixing tank, a first lead screw is threadedly connected to the top surface of the connecting shaft, and a second motor for driving the first lead screw to rotate is arranged inside the cavity.

[0007] The bottom end of the first feed inlet is connected to a hollow block, and a set of discharge holes are opened at the bottom end of the hollow block. A sealing component for sealing the discharge holes is provided on the hollow block. A connecting rod is fixedly connected to the top surface of the mixing tank. One end of the connecting rod extends into the hollow block. A set of stirring plates is fixedly connected to the surface of the connecting rod located inside the hollow block. The second feed inlet is rotatably connected to the top surface of the mixing tank. A rotating component for driving the first feed inlet to rotate is provided inside the mixing tank.

[0008] The rotating assembly includes a first gear and a second gear. The first gear is fixed on the outer wall of the rotating shaft, and the second gear is fixed on the outer wall of the first feed port. The first gear meshes with the second gear.

[0009] The sealing assembly includes a sealing block disposed on the bottom surface of the hollow block, a first magnetic block fixedly connected to the top surface of the sealing block, a first electromagnet repelling the first magnetic block fixedly connected to the bottom surface of the hollow block, and a pair of elastic ropes fixedly connected to the side wall of the sealing block, with the end of the elastic rope away from the sealing block fixedly connected to the outer side wall of the hollow block.

[0010] The top surface of the sealing block has a set of grooves, and a hollow elastic block is fixedly connected to the inner wall of the grooves. The top surface of the elastic block is arc-shaped, and the outer wall of the elastic block has a set of air vents. The position of the air vents is higher than the top surface of the sealing block.

[0011] The inner wall of the mixing tank is rotatably connected to a vertically arranged second lead screw. A cleaning ring is threaded onto the surface of the second lead screw, and the cleaning ring is slidably connected to the inner wall of the mixing tank. A connecting sleeve is slidably connected to the top surface of the second lead screw, and a second magnetic block is fixedly connected to the top surface of the inner wall of the connecting sleeve. A second electromagnet that repels the second magnetic block is fixedly connected to the top surface of the second lead screw. A spring is fixedly connected between the top surface of the lead screw and the inner wall of the connecting sleeve. A third gear that meshes with the second gear is fixedly connected to the outer wall of the connecting sleeve.

[0012] A silicate-based water-based drilling fluid for coalbed methane wells, applicable to the aforementioned processing equipment for such fluids, comprises the following components by weight:

[0013]

[0014] A method for processing silicate water-based drilling fluid for coalbed methane wells, the method comprising the following steps:

[0015] S1: Select sodium-based bentonite, KPAM, PAC-LV, polyamine inhibitor, polyol, nano-blocking agent, ultrafine calcium carbonate, NaOH and fresh water as raw materials, and crush the ultrafine calcium carbonate to 800 mesh.

[0016] S2: Add fresh water to the mixing tank, start the first motor to drive the stirring blades to rotate, slowly add sodium-based bentonite from the second feed inlet, continue stirring for 30 minutes to form a uniform suspension, add soda ash, adjust the pH to 9-10, continue stirring for 20 minutes to promote full hydration of bentonite, let stand for 4-6 hours to allow the bentonite to fully expand and stabilize its viscosity.

[0017] S3: Thus, the polyamine inhibitor and polyol anti-collapse agent are added to the hollow block through the first feed port, and stirred with the help of the stirring plate for 15 to 18 minutes. Then, the mixed additives are discharged into the stirring tube through the discharge port.

[0018] S4: Add nano-blocking agent to the second feed hole in 2-3 batches, with an interval of 5 minutes between each batch. At the same time, add ultrafine calcium carbonate and lubricant and stir for 30 minutes until there is no particle sediment.

[0019] S5: Fine-tune the pH to 9.5-10.5 with NaOH solution, test the density. If it is too high, centrifuge to remove sand; if it is too low, add barite. Finally, discharge it from the outlet pipe to complete the processing of the drilling fluid.

[0020] The beneficial effects of this invention are as follows:

[0021] 1. This invention adds fresh water to a mixing tank, then adds various additives sequentially through a first feed inlet. A first motor drives a rotating shaft to rotate, which in turn drives a connecting shaft to rotate. This allows the stirring blades to mix the fresh water and additives in the mixing tank. During the mixing process, the first motor drives a first lead screw to reciprocate in both forward and reverse directions, causing the lead screw to move the connecting shaft up and down within a groove. This, in turn, moves the stirring blades up and down, allowing them to mix the water and additives while moving, thereby improving the mixing efficiency and uniformity of the additives and water.

[0022] 2. In this invention, the additive is injected into the hollow block through the first feed port, and then the first feed port is driven to rotate by the rotating component. At this time, the hollow block will also rotate, so that the stirring plate can stir and mix the additive. After the mixing is completed, the sealing component is no longer sealed to the discharge port, and the additive can be discharged into the mixing tank from the discharge port. Attached Figure Description

[0023] The invention will now be further described with reference to the accompanying drawings.

[0024] Figure 1 This is a three-dimensional structural diagram of the mixing tank in this invention; Figure 2 This is a schematic diagram of the internal structure of the mixing tank in this invention; Figure 3 yes Figure 2 Enlarged view of point A; Figure 4 yes Figure 2 Enlarged view of point B; Figure 5 This is a schematic diagram of the internal structure of the mixing tank in this invention; Figure 6 This is a schematic diagram of the internal structure of the connecting sleeve and the third gear in this invention. Figure 7 This is a flowchart of the method in this invention.

[0030] In the diagram: 1. Mixing tank; 2. First feed inlet; 3. Second feed inlet; 4. First motor; 5. Connecting shaft; 6. Mixing blade; 7. Rotating shaft; 8. Cavity; 9. Slide groove; 10. Second motor; 11. First lead screw; 12. Hollow block; 13. Connecting rod; 14. Mixing plate; 15. Discharge hole; 16. First gear; 17. Second gear; 18. Sealing block; 19. Elastic rope; 20. First electromagnet; 21. First magnetic block; 22. Elastic block; 23. Second lead screw; 24. Third gear; 25. Connecting sleeve; 26. Cleaning ring; 27. Second electromagnet; 28. Second magnetic block. Detailed Implementation

[0031] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0032] Example 1: As Figures 1 to 4 As shown in the embodiment of the present invention, a special silicate water-based drilling fluid processing device for coalbed methane wells includes a mixing tank 1; the top of the mixing tank 1 is connected to a first feed inlet 2 and a second feed inlet 3, and the bottom of the mixing tank 1 is connected to a discharge pipe; a rotating shaft 7 is rotatably connected to the top surface of the inner wall of the mixing tank 1, a sliding groove 9 is opened on the bottom surface of the rotating shaft 7, a connecting shaft 5 is slidably connected to the inner wall of the sliding groove 9, and multiple sets of stirring blades 6 are fixedly connected to the surface of the connecting shaft 5; a cavity 8 communicating with the sliding groove 9 is opened inside the rotating shaft 7, a first motor 4 for driving the rotating shaft 7 to rotate is fixedly connected to the top surface of the mixing tank 1, a first lead screw 11 is threadedly connected to the top surface of the connecting shaft 5, and a second motor 10 for driving the first lead screw 11 to rotate is provided inside the cavity 8;

[0033] This application adds fresh water to the mixing tank 1 through the second feed port 3, and then adds various additives to the mixing tank 1 sequentially through the first feed port 2. Then, the first motor 4 drives the rotating shaft 7 to rotate, which in turn drives the connecting shaft 5 to rotate, thereby allowing the stirring blades 6 to stir and mix the fresh water and additives in the mixing tank 1. During the mixing process, the first motor 4 can drive the first lead screw 11 to reciprocate in both forward and reverse directions, causing the first lead screw 11 to drive the connecting shaft 5 to move up and down in the slide 9, thereby causing the stirring blades 6 to move up and down. This allows the stirring blades 6 to stir and mix the water and additives while moving, thereby improving the mixing efficiency and uniformity of the additives and water.

[0034] The bottom end of the first feed inlet 2 is connected to a hollow block 12. A set of discharge holes 15 are opened at the bottom end of the hollow block 12. A sealing assembly for sealing the discharge holes 15 is provided on the hollow block 12. A connecting rod 13 is fixedly connected to the top surface of the mixing tank 1. One end of the connecting rod 13 extends into the hollow block 12. A set of stirring plates 14 are fixedly connected to the surface of the connecting rod 13 located inside the hollow block 12. The second feed inlet 3 is rotatably connected to the top surface of the mixing tank 1. A rotating assembly for driving the first feed inlet 2 to rotate is provided inside the mixing tank 1.

[0035] During the processing of drilling fluid, some additives (polyamine inhibitors, polyol anti-collapse agents) need to be mixed in advance and then added to the mixing tube. The above mechanism can inject the additives into the hollow block 12 from the first feed port 2. Then, the first feed port 2 is driven to rotate by the rotating component. At this time, the hollow block 12 will also rotate, so that the mixing plate 14 can stir and mix the additives. After the mixing is completed, the sealing component will no longer seal the discharge port 15. At this time, the additives can be discharged from the discharge port 15 into the mixing tank 1.

[0036] The rotating assembly includes a first gear 16 and a second gear 17. The first gear 16 is fixed on the outer wall of the rotating shaft 7, and the second gear 17 is fixed on the outer wall of the first feed inlet 2. The first gear 16 and the second gear 17 mesh. When the rotating shaft 7 rotates, it will drive the first gear 16 to rotate. At this time, the first gear 16 will drive the second gear 17 to rotate, thereby driving the hollow block 12 to rotate, so that the stirring plate 14 can stir and mix the additives.

[0037] The sealing assembly includes a sealing block 18 disposed on the bottom surface of the hollow block 12. A first magnetic block 21 is fixedly connected to the top surface of the sealing block 18. A first electromagnet 20, which repels the first magnetic block 21, is fixedly connected to the bottom surface of the hollow block 12. A pair of elastic ropes 19 are fixedly connected to the side wall of the sealing block 18. One end of the elastic rope 19 away from the sealing block 18 is fixedly connected to the outer side wall of the hollow block 12. When the additive needs to be discharged from the hollow block 12, the first electromagnet 20 can be activated. At this time, the first electromagnet 20 will push the first magnetic block 21, causing the first magnetic block 21 to move the sealing block 18 away from the hollow block 12. At this time, the discharge hole 15 is no longer sealed by the sealing block 18, so that the additive can be discharged from the discharge hole 15.

[0038] The top surface of the sealing block 18 has a set of grooves, and a hollow elastic block 22 is fixedly connected to the inner wall of the grooves. The top surface of the elastic block 22 is arc-shaped, and the outer wall of the elastic block 22 has a set of air vents. The air vents are positioned higher than the top surface of the sealing block 18. After the additive is discharged from the hollow block 12, the electromagnet can be turned off. At this time, the elastic rope 19 will pull the sealing block 18 to reset, causing the sealing block 18 to move upward. At this time, the elastic block 22 will be squeezed by the bottom surface of the hollow block 12, causing the gas inside the hollow block 12 to be discharged from the air vents. The gas will then blow onto the top surface of the sealing block 18, thereby allowing the additive on the top surface of the sealing block 18 to be blown into the mixing tank 1.

[0039] Example 2: Figure 5As shown in the comparative embodiment one, another embodiment of the present invention is as follows: a vertically arranged second lead screw 23 is rotatably connected to the inner wall of the mixing tank 1. A cleaning ring 26 is threadedly connected to the surface of the second lead screw 23. The cleaning ring 26 is slidably connected to the inner wall of the mixing tank 1. A connecting sleeve 25 is slidably connected to the top surface of the second lead screw 23. A second magnetic block 28 is fixedly connected to the top surface of the inner wall of the connecting sleeve 25. A second electromagnet 27, which repels the second magnetic block 28, is fixedly connected to the top surface of the second lead screw 23. A spring is fixedly connected between the top surface of the lead screw and the inner wall of the connecting sleeve 25. A third gear 24, which meshes with the second gear 17, is fixedly connected to the outer wall of the connecting sleeve 25. Due to the stirring... After the drilling fluid in tank 1 is mixed, it will be discharged from the discharge pipe. At this time, drilling fluid may remain on the inner wall of the mixing tank 1. At this time, the second electromagnet 27 can be activated to push the second magnetic block 28, so that the connecting sleeve 25 drives the third gear 24 to mesh with the second gear 17. When the hollow block 12 rotates, the second gear 17 can drive the third gear 24 to rotate, thereby controlling the second lead screw 23 to rotate, so that the second lead screw 23 drives the cleaning ring 26 to move downward. By driving the rotating shaft 7 to reverse through the second motor 10, the second lead screw 23 can be reversed, thereby controlling the cleaning ring 26 to move upward. During the movement of the cleaning ring 26, the liquid remaining on the inner wall of the mixing tank 1 can be scraped off and discharged.

[0040] A silicate-based water-based drilling fluid for coalbed methane wells, applicable to the aforementioned processing equipment for such fluids, comprises the following components by weight:

[0041]

[0042]

[0043] like Figure 6 As shown, a method for processing silicate-based water-based drilling fluid for coalbed methane wells is described. This method, used to process the aforementioned silicate-based water-based drilling fluid for coalbed methane wells, includes the following steps:

[0044] S1: Select sodium-based bentonite, KPAM, PAC-LV, polyamine inhibitor, polyol, nano-blocking agent, ultrafine calcium carbonate, NaOH and fresh water as raw materials, and crush the ultrafine calcium carbonate to 800 mesh.

[0045] S2: Add fresh water to the mixing tank, start the first motor 4 to drive the stirring blade 6 to rotate, slowly add sodium-based bentonite from the second feed port 3, continue stirring for 30 minutes to form a uniform suspension, add soda ash, adjust the pH to 9-10, continue stirring for 20 minutes to promote full hydration of bentonite, let stand for 4-6 hours to allow the bentonite to fully expand and stabilize its viscosity.

[0046] S3: Thus, the first feed port 2 adds the polyamine inhibitor and the polyol anti-collapse agent into the hollow block 12, and stirs it with the help of the stirring plate 14 for 15 to 18 minutes. Then, the mixed additives are discharged into the stirring tube from the discharge port 15.

[0047] S4: Add nano-blocking agent to the second feed hole in 2-3 batches, with an interval of 5 minutes between each batch. At the same time, add ultrafine calcium carbonate and lubricant and stir for 30 minutes until there is no particle sediment.

[0048] S5: Fine-tune the pH to 9.5-10.5 with NaOH solution, test the density. If it is too high, centrifuge to remove sand; if it is too low, add barite. Finally, discharge it from the outlet pipe to complete the processing of the drilling fluid.

[0049] Working principle: Fresh water is added to the mixing tank 1 through the second feed port 3. Then, various additives are added to the mixing tank 1 sequentially through the first feed port 2. The first motor 4 drives the rotating shaft 7 to rotate, which in turn drives the connecting shaft 5 to rotate. This allows the stirring blades 6 to stir and mix the fresh water and additives in the mixing tank 1. During the mixing process, the first motor 4 drives the first lead screw 11 to reciprocate in both forward and reverse directions. This causes the first lead screw 11 to move the connecting shaft 5 up and down in the slide groove 9, which in turn moves the stirring blades 6 up and down. This allows the stirring blades 6 to stir and mix the water and additives while moving, thereby improving the mixing efficiency and uniformity of the additives and water.

[0050] During the processing of drilling fluid, some additives (polyamine inhibitors, polyol anti-collapse agents) need to be mixed in advance and then added to the mixing tube. The above mechanism can inject the additives into the hollow block 12 from the first feed port 2. Then, the rotating component drives the first feed port 2 to rotate, and the hollow block 12 will also rotate, so that the mixing plate 14 can stir and mix the additives. After the mixing is completed, the sealing component will no longer seal the discharge port 15, and the additives can be discharged from the discharge port 15 into the mixing tank 1. When the rotating shaft 7 in this application rotates, it will drive the first gear 16 to rotate. The first gear 16 will drive the second gear 17 to rotate, thereby driving the hollow block 12 to rotate, so that the mixing plate 14 can stir and mix the additives.

[0051] When the additive needs to be discharged from the hollow block 12, the first electromagnet 20 can be activated. At this time, the first electromagnet 20 will push the first magnetic block 21, causing the first magnetic block 21 to move the sealing block 18 away from the hollow block 12. At this time, the discharge hole 15 is no longer sealed by the sealing block 18, so that the additive can be discharged from the discharge hole 15. After the additive is discharged from the hollow block 12, the electromagnet can be turned off. At this time, the elastic rope 19 will pull the sealing block 18 to reset, causing the sealing block 18 to move upward. At this time, the elastic block 22 will be squeezed by the bottom surface of the hollow block 12, causing the gas inside the hollow block 12 to be discharged from the vent. At this time, the gas will blow onto the top surface of the sealing block 18, so that the additive on the top surface of the sealing block 18 can be blown into the mixing tank 1.

[0052] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0053] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and 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. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A special silicate water-based drilling fluid processing device for coalbed methane wells, comprising a mixing tank (1); the top of the mixing tank (1) is connected to a first feed inlet (2) and a second feed inlet (3), and the bottom of the mixing tank (1) is connected to a discharge pipe; Its features are: The inner wall top surface of the mixing tank (1) is rotatably connected to a rotating shaft (7), the bottom surface of the rotating shaft (7) is provided with a sliding groove (9), the inner wall of the sliding groove (9) is slidably connected to a connecting shaft (5), and multiple sets of stirring blades (6) are fixedly connected to the surface of the connecting shaft (5). The rotating shaft (7) has a cavity (8) that communicates with the slide groove (9). The top surface of the mixing tank (1) is fixedly connected to a first motor (4) that drives the rotating shaft (7) to rotate. The top surface of the connecting shaft (5) is threadedly connected to a first lead screw (11). The cavity (8) is provided with a second motor (10) that drives the first lead screw (11) to rotate.

2. The silicate water-based drilling fluid processing device for coalbed methane wells according to claim 1, characterized in that: The bottom end of the first feed inlet (2) is connected to a hollow block (12). The bottom end of the hollow block (12) is provided with a set of discharge holes (15). A sealing component is provided on the hollow block (12) to seal the discharge holes (15). A connecting rod (13) is fixedly connected to the top surface of the mixing tank (1). One end of the connecting rod (13) extends into the hollow block (12). A set of stirring plates (14) is fixedly connected to the surface of the connecting rod (13) inside the hollow block (12). The second feed inlet (3) is rotatably connected to the top surface of the mixing tank (1). A rotating component is provided inside the mixing tank (1) to drive the first feed inlet (2) to rotate.

3. The silicate water-based drilling fluid processing device for coalbed methane wells according to claim 2, characterized in that: The rotating assembly includes a first gear (16) and a second gear (17). The first gear (16) is fixed on the outer wall of the rotating shaft (7), and the second gear (17) is fixed on the outer wall of the first feed port (2). The first gear (16) meshes with the second gear (17).

4. The silicate water-based drilling fluid processing device for coalbed methane wells according to claim 3, characterized in that: The sealing assembly includes a sealing block (18) disposed on the bottom surface of the hollow block (12), a first magnetic block (21) is fixedly connected to the top surface of the sealing block (18), a first electromagnet (20) repelling the first magnetic block (21) is fixedly connected to the bottom surface of the hollow block (12), and a pair of elastic ropes (19) are fixedly connected to the side wall of the sealing block (18), with one end of the elastic rope (19) away from the sealing block (18) being fixedly connected to the outer side wall of the hollow block (12).

5. The silicate water-based drilling fluid processing device for coalbed methane wells according to claim 4, characterized in that: The top surface of the sealing block (18) is provided with a set of grooves, and a hollow elastic block (22) is fixedly connected to the inner wall of the grooves. The top surface of the elastic block (22) is arc-shaped, and a set of air vents is provided on the outer wall of the elastic block (22). The position of the air vents is higher than the top surface of the sealing block (18).

6. The silicate water-based drilling fluid processing device for coalbed methane wells according to claim 5, characterized in that: The inner wall of the mixing tank (1) is rotatably connected to a vertically arranged second lead screw (23). A cleaning ring (26) is threadedly connected to the surface of the second lead screw (23). The cleaning ring (26) is slidably connected to the inner wall of the mixing tank (1). A connecting sleeve (25) is slidably connected to the top surface of the second lead screw (23). A second magnetic block (28) is fixedly connected to the top surface of the inner wall of the connecting sleeve (25). A second electromagnet (27) that repels the second magnetic block (28) is fixedly connected to the top surface of the second lead screw (23). A spring is fixedly connected between the top surface of the lead screw and the inner wall of the connecting sleeve (25). A third gear (24) that meshes with the second gear (17) is fixedly connected to the outer wall of the connecting sleeve (25).

7. A silicate-based water-based drilling fluid for coalbed methane wells, wherein the drilling fluid is suitable for the processing apparatus for the silicate-based water-based drilling fluid for coalbed methane wells as described in claim 6, characterized in that: Includes the following substances in parts by weight:

8. A method for processing silicate-based water-based drilling fluid for coalbed methane wells, the method being used to process the silicate-based water-based drilling fluid for coalbed methane wells as described in claim 7, characterized in that: The method includes the following steps: S1: Select sodium bentonite, KPAM, PAC-LV, polyamine inhibitor, polyol, nano-blocking agent, ultrafine calcium carbonate, NaOH and fresh water as raw materials, and grind the ultrafine calcium carbonate to 800 mesh. S2: Add fresh water to the mixing tank, start the first motor (4) to drive the stirring blade (6) to rotate, so that sodium-based bentonite is slowly added through the second feed inlet (3), and continue stirring for 30 minutes to form a uniform suspension. Add soda ash, adjust the pH to 9-10, continue stirring for 20 minutes to promote full hydration of bentonite, and let stand for 4-6 hours to allow the bentonite to fully expand and stabilize its viscosity. S3: Thus, the first feed port (2) adds the polyamine inhibitor and the polyol anti-collapse agent into the hollow block (12), and stirs it with the help of the stirring plate (14) for 15 to 18 minutes. Then, the mixed additives are discharged into the stirring tube from the discharge port (15).

9. The method for processing silicate water-based drilling fluid for coalbed methane wells according to claim 8, characterized in that: The method also includes the following steps: S4: Add nano-blocking agent to the second feed hole in 2-3 batches, with an interval of 5 minutes between each batch. At the same time, add ultrafine calcium carbonate and lubricant and stir for 30 minutes until there is no particle sediment. S5: Fine-tune the pH to 9.5-10.5 with NaOH solution, test the density. If it is too high, centrifuge to remove sand; if it is too low, add barite. Finally, discharge it from the outlet pipe to complete the processing of the drilling fluid.

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