Low-permeability coal seam gas extraction equipment and method

Abstract

The invention is suitable for the technical field of coal mine gas extraction, and provides low-permeability coal seam gas extraction equipment and a low-permeability coal seam gas extraction method.The low-permeability coal seam gas extraction equipment comprises a base plate; the box body is fixed on the base plate, and an extraction mechanism for extracting gas is arranged on the box body; the driving mechanism and the filtering mechanism are arranged in the box body; and the filtering mechanism is used for purifying the extracted gas-liquid mixture. According to the low-permeability coal seam gas extraction equipment and method provided by the scheme, the adaptability of the equipment to the low-permeability coal seam is integrally improved, the operation procedures and the drilling collapse risk are reduced, and high-efficiency extraction of the low-permeability coal seam gas is achieved.

Description

Technical Field

[0001] This invention belongs to the field of coal mine gas extraction technology, and particularly relates to a gas extraction device and method for low-permeability coal seams. Background Technology

[0002] Low-permeability coal seams generally have a permeability of less than 1×10⁻⁶. -15 m 2 Low-permeability coal seams are characterized by low porosity, poor pore connectivity, strong gas adsorption capacity, high desorption and transport resistance, and poor permeability. This results in low gas extraction efficiency, long extraction cycles, and difficulty in achieving extraction standards, making it a core challenge for coal mine gas disaster prevention and gas resource utilization. Gas extraction equipment plays a crucial role in preventing gas disasters in low-permeability coal seams and ensuring safe coal mining; however, existing equipment still needs improvement in the coordination between drilling operations and gas extraction, as well as the rationality of fluid transport.

[0003] Traditional drill pipes only have drilling and cutting functions and lack integrated fluid transport channels. Water supply and slag removal during drilling are independent of subsequent gas transport, requiring multiple disassemblies to switch processes, resulting in low operational efficiency. Frequent disassembly and assembly can disturb the borehole wall, inducing borehole collapse, and is particularly unsuitable for fragile geological conditions such as low-permeability coal seams. Therefore, based on the geological characteristics of low-permeability coal seams and the gas occurrence and migration characteristics, how to improve the adaptability of gas drainage equipment and achieve efficient gas extraction from low-permeability coal seams has become an urgent technical challenge. Summary of the Invention

[0004] This invention provides a gas extraction device and method for low-permeability coal seams, aiming to solve the problem mentioned in the background art of how to improve the adaptability of gas extraction equipment and achieve efficient gas extraction from low-permeability coal seams based on the geological characteristics and gas occurrence and migration characteristics of low-permeability coal seams.

[0005] The present invention is implemented as follows: a low-permeability coal seam gas extraction device, comprising: a base plate; a box fixed on the base plate, wherein the box is provided with an extraction mechanism for extracting gas; a drive mechanism and a filter mechanism disposed in the box; wherein the filter mechanism is used to purify the extracted gas-liquid mixture.

[0006] Preferably, the extraction mechanism includes: a height-adjustable mounting base disposed on the housing; a power rod rotatably mounted on the mounting base via a bearing, the front end of the power rod having a threaded groove for mounting a drill rod; and water and air channels formed on the power rod.

[0007] Preferably, the extraction mechanism further includes an adjustment mechanism for adjusting the height of the mounting base. The adjustment mechanism comprises: a partition fixed inside the housing, on which a first electro-hydraulic rod is fixed; an adjustment frame fixed to the push rod of the first electro-hydraulic rod, the top of which is fixedly connected to the corresponding mounting base; a pipe rack fixed to the adjustment frame, on which a dual-channel rotary joint is fixed; a second connecting pipe fixedly connected to the air inlet end of the dual-channel rotary joint; a second telescopic pipe fixedly connected to the air outlet end of the dual-channel rotary joint; an extraction pump fixed to the partition, the air inlet end of which is fixedly connected to the second telescopic pipe; and a guide plate slidably installed inside the housing, the top of which is fixedly connected to the corresponding mounting base.

[0008] Preferably, the filtration mechanism includes: a gas-water separator fixed on the partition plate; a gas guide pipe fixedly connected to the gas inlet end of the gas-water separator, the gas inlet end of the gas guide pipe being fixedly connected to the gas outlet end of the extraction pump; and a gas outlet pipe fixedly connected to the gas outlet end of the gas-water separator for connecting to a gas conveying pipeline.

[0009] Preferably, the drive mechanism includes: a spline tube rotatably mounted in the housing via a bearing seat; a spline rod rotatably mounted on the adjusting frame via a bearing, the bottom end of the spline rod being inserted into the spline tube; a motor and a speed regulator fixed in the housing, the output shaft of the motor being fixedly connected to the input shaft of the speed regulator via a coupling; a first bevel gear fixed to the output shaft of the speed regulator and the spline tube respectively and meshing with each other; a second bevel gear fixed to the spline rod and the power rod respectively and meshing with each other; and two fourth bevel gears fixed to the spline tube and the input shaft of the extraction pump respectively and meshing with each other.

[0010] Preferably, the housing is equipped with a water supply mechanism for supplying drilling water. The water supply mechanism includes: a water guide shell fixed inside the housing; the outlet of the water guide shell is fixedly connected to the inlet of the dual-channel rotary joint via a water guide pipe and a first telescopic pipe; the outlet of the dual-channel rotary joint is fixedly connected to the water channel via a first connecting pipe; a rotating rod rotatably mounted inside the water guide shell via a sealed bearing; an impeller fixed on the rotating rod; a third bevel gear fixed to the rotating rod and the splined tube respectively and meshing with each other; and an inlet pipe fixedly connected to the inlet of the water guide shell for connecting to an external water supply pipeline.

[0011] Preferably, a positioning mechanism is provided inside the housing, the positioning mechanism including a second electro-hydraulic rod, an assembly plate and a positioning plate; the second electro-hydraulic rod is fixed inside the housing, the bottom end of the push rod of the second electro-hydraulic rod is fixedly connected to the assembly plate, and the positioning plate is fixed at the bottom of the assembly plate, the bottom end of which is conical and used to insert into the coal gangue layer to achieve equipment positioning.

[0012] Preferably, a connecting seat is fixed at the tail of the base plate for installing a steel wire rope, and a pluggable pin is provided on the connecting seat.

[0013] Preferably, a base frame is symmetrically fixed to the bottom of the base plate, and a track wheel is rotatably mounted on the base frame for moving along the track.

[0014] The present invention also proposes a method for gas extraction equipment in low-permeability coal seams, the method comprising the following steps: Step 1: Set the track wheels on the bottom frame of the base plate onto the preset track, install the wire rope through the connecting seat at the tail of the base plate and insert the pin to fix it, and use the wire rope to lower the equipment into the inclined mine channel until it reaches the designated extraction point, then stop lowering and fix the rope.

[0015] Step 2: Install the extension drill rod thread onto the front thread of the power rod, ensuring that the water channel on the drill rod is aligned with the water channel on the power rod and that the air channel on the drill rod is connected to the air channel on the power rod. Then, install the drill bit thread with the air and water holes onto the front end of the extension drill rod.

[0016] Step 3: Activate the second electro-hydraulic rod. Its push rod extends and drives the assembly plate to descend, so that the cone-shaped structure at the bottom end of the positioning plate at the bottom of the assembly plate is inserted into the coal gangue layer. After the equipment positioning is completed, close the second electro-hydraulic rod.

[0017] Step 4: Activate the first electro-hydraulic rod according to the extraction requirements. Its push rod rises, driving the adjustment frame to rise. The pipe rack, spline rod and guide plate fixed to the adjustment frame rise synchronously. The mounting seat at the top of the guide plate adjusts its height accordingly. After the power rod reaches the appropriate drilling height, the first electro-hydraulic rod is closed.

[0018] Step 5: Connect the water inlet pipe to the external water supply line and the gas outlet pipe to the gas delivery line. Ensure that all pipe connections are sealed and check that the check valve and solenoid valve are in normal working condition.

[0019] Step Six: Start the motor. The motor drives the speed regulator through the coupling. The first bevel gear on the output shaft of the speed regulator meshes with the first bevel gear on the spline tube, driving the spline tube to rotate. The spline rod rotates synchronously with the spline tube.

[0020] Step 7: The second bevel gear at the top of the spline rod meshes with the second bevel gear on the power rod, driving the power rod, the extension drill rod, and the drill bit to rotate. During the rotation of the drill bit, it pushes the equipment forward along the track and drills into the low-permeability coal seam.

[0021] Step 8: When the spline tube rotates, the third bevel gear on it meshes with the third bevel gear on the rotating rod, driving the rotating rod and impeller inside the water guide shell to rotate and generate negative pressure. External water enters the water guide shell through the inlet pipe, and then enters the water channel of the power rod through the first telescopic pipe, the double-channel rotary joint, and the first connecting pipe in sequence. It then flows out from the drill bit water hole through the drill rod water channel to cool the drill bit.

[0022] Step 9: The two fourth bevel gears on the spline tube mesh with the two fourth bevel gears on the input shaft of the extraction pump, driving the extraction pump to run. The gas-liquid mixture in the coal seam enters the extraction pump through the drill bit air hole, drill rod air passage, power rod air passage, second connecting pipe, double-channel rotary joint, and second telescopic pipe, and is then sent to the gas-liquid separator by the extraction pump through the air guide pipe.

[0023] Step 10: The gas-liquid separator separates the gas-liquid mixture, and the separated gas is discharged into the gas delivery pipeline through the gas outlet pipe.

[0024] Step 11: After the gas extraction is completed, turn off the motor, reverse the second electric hydraulic rod to detach the positioning plate from the coal gangue layer, and use the wire rope to retrieve the equipment along the track to the designated position. Disassemble the drill bit, extend the drill rod and all pipelines to complete the extraction operation.

[0025] Compared with related technologies, the low-permeability coal seam gas extraction equipment and method provided by the present invention have the following beneficial effects: By integrating water and gas channels through a power rod, and combining it with a drive mechanism to drive the coordinated operation of multiple components such as drilling, water supply, and extraction, along with adjustment, filtration, and cooling mechanisms, the equipment achieves stable movement and positioning by relying on a base plate, track wheels, and positioning mechanism. Gas-liquid separation and wastewater circulation are achieved by using a gas-liquid separator, filter, and water collection tank. This improves the overall adaptability of the equipment to low-permeability coal seams, reduces operational procedures and the risk of borehole collapse, and enables efficient extraction of gas from low-permeability coal seams. At the same time, it simplifies the equipment structure, reduces energy consumption, and extends the service life of the equipment. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the main structure of a low-permeability coal seam gas extraction device provided by the present invention; Figure 2 This is a schematic diagram of the main cross-sectional structure of a low-permeability coal seam gas extraction device provided by the present invention; Figure 3 for Figure 2 An enlarged structural diagram of part A shown in the figure; Figure 4 for Figure 2 An enlarged structural diagram of part B shown in the figure; Figure 5 for Figure 2 An enlarged structural diagram of section C shown in the figure; Figure 6 for Figure 2 An enlarged structural diagram of part D shown in the figure; Figure 7 This is a schematic diagram of the base plate in this invention; Figure 8 This is a schematic diagram of the assembly plate and positioning plate in this invention.

[0027] Reference numerals: 1. Base plate; 2. Track wheel; 3. Housing; 4. Mounting seat; 5. Power rod; 6. Water channel; 7. Air channel; 8. Partition plate; 9. Guide plate; 10. First electro-hydraulic rod; 11. Adjusting frame; 12. Spline tube; 13. Spline rod; 14. Motor; 15. Speed ​​regulator; 16. First bevel gear; 17. Second bevel gear; 18. Double-channel rotary joint; 19. First connecting pipe; 20. Second connecting pipe; 21. Pipe rack; 22. First telescopic pipe; 23. Second telescopic pipe; 24. Extraction pump; 25. 16. Air-water separator; 27. Air outlet pipe; 28. Water guide shell; 29. ​​Rotating rod; 30. Impeller; 31. Water inlet pipe; 32. Water guide pipe; 33. Third bevel gear; 34. Connecting seat; 35. Fourth bevel gear; 36. Cooling shell; 37. Water guide cavity; 38. Fan blade; 39. Connecting pipe; 40. Exhaust pipe; 41. Water collection tank; 42. Water outlet pipe; 43. Solenoid valve; 44. Drain pipe; 45. Check valve; 46. Second electro-hydraulic rod; 47. Assembly plate; 48. Positioning plate; 49. Filter. Detailed Implementation

[0028] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0029] This invention provides a low-permeability coal seam gas extraction device, such as... Figure 1-8 As shown, the low-permeability coal seam gas extraction equipment includes: a base plate 1; a box 3 fixed on the base plate 1, wherein the box 3 is provided with an extraction mechanism for extracting gas; a drive mechanism and a filter mechanism disposed within the box 3; and the filter mechanism is used to purify the extracted gas-liquid mixture.

[0030] In this embodiment, when using the low-permeability coal seam gas extraction equipment, the base plate 1 is first erected on the preset track via the bottom track wheel 2. The steel wire rope is fixed by the connecting seat 34 at the tail of the base plate 1. After the equipment is lowered to the designated extraction point, the second electric hydraulic rod 46 is started to push the positioning plate 48 into the coal gangue layer to complete the positioning. Then, the extension drill rod and drill bit are assembled on the power rod 5. The height of the mounting seat 4 is adjusted by the first electric hydraulic rod 10 to adapt to the drilling requirements. The water inlet pipe 31 is connected to the external water supply pipeline, and the gas outlet pipe 27 is connected to the gas conveying pipeline. After checking the status of each pipeline and valve, the motor 14 is started. The power rod 5 and the drill bit are driven by the drive mechanism to rotate and carry out the drilling operation.

[0031] When the motor 14 is running, it drives the speed regulator 15 to work, which drives the spline tube 12 and spline rod 13 to rotate via the first bevel gear 16. The spline rod 13 drives the power rod 5 to rotate via the second bevel gear 17. At the same time, the spline tube 12 drives the impeller 30 in the water guide shell 28 to generate negative pressure via the third bevel gear 33, so that the cooling water flows out from the drill bit through the water channel 6 of the power rod 5 and the drill rod water channel to achieve borehole cooling. The spline tube 12 also drives the extraction pump 24 to run via the fourth bevel gear 35, which extracts the gas-liquid mixture in the coal seam through the gas channel 7 of the power rod 5 to the gas-liquid separator 25. The separated gas is transported through the gas outlet pipe 27, and the wastewater is filtered and cooled by the filtration mechanism before flowing into the water inlet pipe 31 for recycling.

[0032] By integrating water channel 6 and gas channel 7 through power rod 5, the drilling water supply and gas extraction processes can be carried out simultaneously without disassembling the equipment, reducing the number of process switching and equipment disassembly frequency, reducing the risk of borehole collapse, and adapting to the fragile geological conditions of low-permeability coal seams; relying on the same drive mechanism to drive the coordinated operation of multiple components of drilling, water supply, and extraction, simplifying the operation process and improving operation efficiency; gas-water separator 25 and filter 49 work together to achieve gas purification and wastewater recycling, reducing water consumption; fan blade 38 and cooling shell 36 work together to reduce the operating temperature of extraction pump 24 and extend the service life of the equipment.

[0033] In a further preferred embodiment of the present invention, the extraction mechanism includes: a mounting base 4 disposed on the housing 3 and having an adjustable height; a power rod 5 rotatably mounted on the mounting base 4 via a bearing, the front end of the power rod 5 having a threaded groove for mounting a drill rod; and a water channel 6 and an air channel 7 formed on the power rod 5.

[0034] In this embodiment, the mounting base 4 of the extraction mechanism is assembled on the housing 3, and its height can be adjusted by the matching adjustment components. The power rod 5 is rotatably mounted on the mounting base 4 through the bearing. During operation, the drill rod is assembled and fixed through the threaded groove at the front end of the power rod 5 to ensure that the drill rod is connected to the water channel 6 and air channel 7 on the power rod 5. Then, the drill bit is installed at the front end of the drill rod. After the assembly of the extraction mechanism and the drilling tool is completed, the drilling operation is prepared in accordance with the equipment positioning process.

[0035] During the drilling process, the drive mechanism drives the power rod 5 to rotate, and the power rod 5 drives the drill rod and drill bit to operate synchronously to cut into the coal seam. At the same time, external cooling water is transported to the drill rod through the water channel 6 of the power rod 5 and finally flows out from the drill bit to achieve cooling. The mixture of gas and water vapor generated in the coal seam enters the drill rod through the drill bit vent and is then extracted by the extraction mechanism through the vent 7 of the power rod 5, so that the drilling and gas delivery actions are carried out synchronously.

[0036] The power rod 5 integrates the water channel 6 and the gas channel 7, eliminating the need for switching between drilling and gas extraction processes and the disassembly and assembly operations required in traditional equipment. This reduces operation time and lowers the risk of borehole collapse caused by frequent disassembly and assembly, making it suitable for fragile geological conditions in low-permeability coal seams. The height-adjustable mounting base 4 allows the power rod 5 and drilling tools to adapt to drilling needs at different heights, improving the operational flexibility of the extraction mechanism. The integrated design of the gas and water channels also simplifies pipeline layout and helps improve overall operational stability.

[0037] In a further preferred embodiment of the present invention, the extraction mechanism further includes an adjustment mechanism for adjusting the height of the mounting base 4. The adjustment mechanism comprises: a partition 8 fixed inside the housing 3, on which a first electro-hydraulic rod 10 is fixed; an adjustment frame 11 fixed to the push rod of the first electro-hydraulic rod 10, the top of which is fixedly connected to the corresponding mounting base 4; a pipe rack 21 fixed to the adjustment frame 11, on which a dual-channel rotary joint 18 is fixed; a second connecting pipe 20 fixedly connected to the air inlet end of the dual-channel rotary joint 18; a second telescopic pipe 23 fixedly connected to the air outlet end of the dual-channel rotary joint 18; an extraction pump 24 fixed to the partition 8, the air inlet end of which is fixedly connected to the second telescopic pipe 23; and a guide plate 9 slidably installed inside the housing 3, the top of which is fixedly connected to the corresponding mounting base 4.

[0038] In this embodiment, when the height of the mounting base 4 needs to be adjusted, the first electric hydraulic rod 10 is activated. Its push rod drives the adjusting frame 11 to move up and down. The adjusting frame 11 drives the mounting base 4 and the guide plate 9 to slide synchronously. The guide plate 9 provides guidance for the movement of the mounting base 4, so that the power rod 5 is adjusted to the appropriate height along with the mounting base 4. During drilling and extraction, the gas-liquid mixture in the coal seam enters the dual-channel rotary joint 18 through the second connecting pipe 20, and is then transported to the extraction pump 24 through the second telescopic pipe 23, ensuring unobstructed gas flow while adapting to the height adjustment of the mounting base 4.

[0039] The adjustment mechanism drives the adjustment frame 11 through the first electric hydraulic rod 10, achieving stable height adjustment of the mounting base 4 to meet the drilling requirements of different coal seam locations. The guide plate 9 enhances the stability of the mounting base 4 during movement and prevents the power rod 5 from deviating. The pipe rack 21 fixes the dual-channel rotary joint 18, which, together with the second telescopic pipe 23, adapts to the air circuit expansion and contraction during height adjustment. Height adjustment can be completed without disassembling the pipeline, reducing the operation process. At the same time, the extraction pump 24 is fixed on the partition plate 8, improving the structural stability of the extraction process.

[0040] In a further preferred embodiment of the present invention, the filtration mechanism includes: a gas-water separator 25 fixed on the partition plate 8; a gas guide pipe 26 fixedly connected to the gas inlet end of the gas-water separator 25, the gas inlet end of the gas guide pipe 26 being fixedly connected to the gas outlet end of the extraction pump 24; and a gas outlet pipe 27 fixedly connected to the gas outlet end of the gas-water separator 25 for connecting to a gas conveying pipeline.

[0041] In this embodiment, after the extraction pump 24 extracts the gas-liquid mixture in the coal seam, it sends it into the gas pipe 26 through its gas outlet. The gas pipe 26 transports the mixture to the gas-liquid separator 25. The gas-liquid separator 25 separates the mixture. The separated gas is sent into the gas conveying pipeline through the gas outlet 27, so that the gas can smoothly enter the subsequent conveying stage and realize gas-liquid separation. The gas-liquid separator 25 is fixed to the partition plate 8 to improve structural stability. It connects with the extraction pump 24 via the gas guide pipe 26 to promptly separate the extracted mixture, removing moisture and some impurities from the gas. The gas outlet pipe 27 is specifically used to transport the separated gas, reducing the impact of moisture on subsequent pipelines and equipment. It also simplifies the gas-liquid separation process and works in synergy with the extraction and regulating mechanisms to improve overall extraction efficiency.

[0042] In a further preferred embodiment of the present invention, the driving mechanism includes: a spline tube 12 rotatably mounted in the housing 3 via a bearing seat; a spline rod 13 rotatably mounted on the adjusting frame 11 via a bearing, the bottom end of the spline rod 13 being inserted into the spline tube 12; a motor 14 and a speed regulator 15 fixed in the housing 3, the output shaft of the motor 14 being fixedly connected to the input shaft of the speed regulator 15 via a coupling; a first bevel gear 16 respectively fixed to the output shaft of the speed regulator 15 and the spline tube 12 and meshing with each other; a second bevel gear 17 respectively fixed to the spline rod 13 and the power rod 5 and meshing with each other; and two fourth bevel gears 35 respectively fixed to the spline tube 12 and the input shaft of the extraction pump 24 and meshing with each other.

[0043] In this embodiment, after the motor 14 is started, its power is transmitted to the speed regulator 15 via a coupling. After the speed regulator 15 adjusts the speed, it drives the spline tube 12 to rotate through the first bevel gear 16 on the output shaft. The spline tube 12 drives the spline rod 13 inserted therein to rotate synchronously. The spline rod 13 drives the power rod 5 to rotate through the second bevel gear 17 at the top, providing power for the drilling operation. At the same time, the spline tube 12 drives the input shaft of the extraction pump 24 to rotate through the fourth bevel gear 35, so that the extraction pump 24 starts synchronously to carry out the extraction operation.

[0044] The drive mechanism is powered by a single motor 14, which is linked to the spline structure via a bevel gear set to enable simultaneous drilling and extraction operations, simplifying the power transmission structure and reducing the space occupied by the equipment. The spline tube 12 and spline rod 13 are matched to allow the adjustment frame 11 to move the spline rod 13 up and down without affecting the power transmission, thus forming a synergy with the adjustment mechanism.

[0045] In a further preferred embodiment of the present invention, a water supply mechanism is provided inside the housing 3 for supplying drilling water. The water supply mechanism includes: a water guide shell 28 fixed inside the housing 3; the outlet of the water guide shell 28 is fixedly connected to the inlet end of the dual-channel rotary joint 18 through a water guide pipe 32 and a first telescopic pipe 22; the outlet end of the dual-channel rotary joint 18 is fixedly connected to the water channel 6 through a first connecting pipe 19; a rotating rod 29 rotatably mounted inside the water guide shell 28 through a sealed bearing; an impeller 30 fixed on the rotating rod 29; a third bevel gear 33 fixed on the rotating rod 29 and the splined pipe 12 and meshing with each other; and an inlet pipe 31 fixedly connected to the inlet end of the water guide shell 28 for connecting to an external water supply pipeline.

[0046] In this embodiment, when the drive mechanism is running, the spline tube 12 rotates, driving the meshing third bevel gear 33 to rotate. The third bevel gear 33 drives the rotating rod 29 and the impeller 30 to rotate synchronously. The rotation of the impeller 30 generates negative pressure, causing external water to enter the water guide shell 28 through the water inlet pipe 31. The water flows sequentially through the water guide pipe 32 and the first telescopic pipe 22 into the dual-channel rotary joint 18, and then through the first connecting pipe 19 into the water channel 6 of the power rod 5, finally delivering it to the drill bit to cool the drilling operation, thus realizing the simultaneous operation of water supply, drilling, and extraction. The water supply mechanism is powered by the spline tube 12 of the drive mechanism, eliminating the need for additional drive components, simplifying the overall structure of the equipment, and reducing energy consumption. The first telescopic tube 22 can be adapted to the adjustment frame 11 to drive the dual-channel rotary joint 18 to move up and down, ensuring unobstructed and well-sealed water supply pipeline during height adjustment. The sealed bearing reduces the risk of leakage from the water guide shell 28, and the impeller 30, in conjunction with the rotating rod 29, stably delivers water flow, continuously cooling the drill bit, reducing component wear caused by high temperatures during drilling, and improving operational continuity.

[0047] In a further preferred embodiment of the present invention, a positioning mechanism is provided inside the housing 3. The positioning mechanism includes a second electro-hydraulic rod 46, an assembly plate 47, and a positioning plate 48. The second electro-hydraulic rod 46 is fixed inside the housing 3. The bottom end of the push rod of the second electro-hydraulic rod 46 is fixedly connected to the assembly plate 47. The positioning plate 48 is fixed to the bottom of the assembly plate 47, and its bottom end is conical, used to insert into the coal gangue layer to achieve equipment positioning.

[0048] In this embodiment, when the equipment moves to the designated position and reaches the extraction layer, and there is no need to continue drilling, the second electro-hydraulic rod 46 is activated. Its push rod extends and drives the assembly plate 47 to move downward. The assembly plate 47 drives the bottom positioning plate 48 to move downward synchronously, so that the cone-shaped structure at the bottom of the positioning plate 48 is inserted into the coal gangue layer to achieve the positioning of the equipment. Then the second electro-hydraulic rod 46 is closed to provide a stable foundation for subsequent gas extraction operations. The positioning mechanism is driven by the second electro-hydraulic rod 46, making it easy to operate and adaptable to complex underground working environments. It can quickly fix and unlock the equipment. The cone-shaped positioning plate 48 facilitates cutting into the coal gangue layer, improving the stability of the equipment during the extraction process and reducing the impact of equipment shaking on the extraction operation.

[0049] In a further preferred embodiment of the present invention, a connecting seat 34 is fixed at the tail of the base plate 1 for installing a steel wire rope, and a pluggable pin is provided on the connecting seat 34.

[0050] In this embodiment, after the equipment is transported to the mine entrance, the wire rope is attached to the connecting seat 34, and a pin is inserted to limit and fix the rope. The base plate 1 is pulled by the wire rope, which drives the track wheel 2 to move along the preset track, transporting the equipment to the designated extraction point. After reaching the position, the pin is pulled out to unlock the rope, and then the positioning mechanism is used to fix the equipment and carry out subsequent operations. The connecting seat 34 provides a stable mounting point for the wire rope. The pluggable pin facilitates quick and easy fixing and unlocking of the rope, simplifying the operation process during equipment lowering and retrieval, and meeting the needs of efficient underground operations. The limiting function of the pin improves the stability of the rope connection, reduces the risk of the rope falling off during equipment movement, and has a simple structure that is easy to maintain. In conjunction with the track wheel 2, it enhances the reliability of equipment movement in inclined mine tunnels.

[0051] In a further preferred embodiment of the present invention, a base frame is symmetrically fixed to the bottom of the base plate 1, and a track wheel 2 is rotatably mounted on the base frame for moving along the track.

[0052] In this embodiment, after the equipment is transported to the mine entrance, the steel wire rope is fixed by the connecting seat 34. With the help of the rope, the base plate 1 is pulled, which drives the track wheel 2 on the base frame to roll along the preset track, smoothly transporting the equipment to the designated extraction point. After reaching the position, the rope is unlocked and the positioning mechanism is activated to fix the equipment. The track wheel 2 remains in contact with the track, providing stable support for subsequent operations.

[0053] To further improve the performance of this device, in addition to the above-mentioned solutions, this solution also includes the following embodiments: In another embodiment of the present invention, a cooling mechanism is provided inside the housing 3 for cooling the extraction pump 24. The cooling mechanism includes: a cooling shell 36 disposed outside the extraction pump 24, a water guiding cavity 37 disposed on the cooling shell 36 for guiding the water discharged from and filtered by the gas-liquid separator 25; a filter 49 disposed inside the housing 3, the inlet and outlet of the filter 49 being connected to the outlet of the gas-liquid separator 25 and the water guiding cavity 37 respectively via connecting pipes 39; and a water valve disposed at the outlet of the gas-liquid separator 25, which is fixedly connected to the water guiding cavity 37. The water outlet has a water outlet pipe 42, on which a solenoid valve 43 is installed. A water collection tank 41 is fixed at the bottom of the partition plate 8. The water inlet of the water collection tank 41 is fixedly connected to the outlet of the water outlet pipe 42. A drain pipe 44 is fixedly connected to the outlet of the water collection tank 41. The outlet of the drain pipe 44 is fixedly connected to the water inlet pipe 31. A one-way valve 45 is installed on the drain pipe 44. An exhaust pipe 40 is fixedly connected to the cooling shell 36. The exhaust end of the exhaust pipe 40 extends out of the box body 3. A fan blade 38 is fixed on the input shaft of the extraction pump 24.

[0054] In this embodiment, the cooling mechanism is assembled inside the housing 3 around the extraction pump 24. The cooling shell 36 is fitted outside the extraction pump 24 and forms a water guiding cavity 37. The filter 49 is connected to the water outlet of the gas-water separator 25 and the water guiding cavity 37 through the connecting pipe 39. A water valve is provided at the water outlet of the gas-water separator 25 to control the water flow. The water outlet pipe 42 connects the water outlet of the water guiding cavity 37 to the water collection tank 41. The solenoid valve 43 is assembled on the water outlet pipe 42. The drain pipe 44 connects the water collection tank 41 and the water inlet pipe 31 and is equipped with a one-way valve 45. The exhaust pipe 40 is fixed to the cooling shell 36 and extends out of the housing 3. The fan blade 38 is fixed on the input shaft of the extraction pump 24 and works in conjunction with other mechanisms. When the extraction pump 24 is running, its input shaft drives the fan blades 38 to rotate synchronously, generating airflow to blow heat onto the cooling shell 36. The hot air is discharged from the housing 3 through the exhaust pipe 40. At the same time, the water valve at the outlet end of the air-water separator 25 is opened, and the separated wastewater enters the filter 49 through the connecting pipe 39 for filtration. After filtration, the water flows into the water guiding chamber 37 to cool the extraction pump 24 with water. Then, it flows into the water collection tank 41 through the outlet pipe 42 and the solenoid valve 43, and finally flows into the inlet pipe 31 through the drain pipe 44 and the one-way valve 45 for recycling. The cooling mechanism combines air and water cooling, eliminating the need for additional drive components. It relies on the input shaft of the extraction pump 24 to drive the fan blades 38, simplifying the structure and reducing energy consumption. The filter 49 purifies wastewater and, in conjunction with the one-way valve 45, prevents backflow, enabling water resource recycling.

[0055] The present invention also proposes a method for gas extraction equipment in low-permeability coal seams, the method comprising the following steps: Step 1: Place the track wheel 2 on the bottom frame of the base plate 1 onto the preset track, install the wire rope through the connecting seat 34 at the tail of the base plate 1 and insert the pin to fix it, and use the wire rope to lower the equipment into the inclined mine channel until it reaches the designated extraction point, then stop lowering and fix the rope.

[0056] Step 2: Install the extension drill rod thread onto the front thread of the power rod 5, ensuring that the water channel on the drill rod is aligned with the water channel 6 of the power rod 5 and that the air channel on the drill rod is connected to the air channel 7 of the power rod 5. Then, install the drill bit thread with the air and water holes onto the front end of the extension drill rod.

[0057] Step 3: Activate the second electro-hydraulic rod 46. Its push rod extends and drives the assembly plate 47 to descend, so that the cone-shaped structure at the bottom end of the positioning plate 48 at the bottom of the assembly plate 47 is inserted into the coal gangue layer. After the equipment positioning is completed, close the second electro-hydraulic rod 46.

[0058] Step 4: Start the first electric hydraulic rod 10 according to the extraction requirements. Its push rod rises and drives the adjustment frame 11 to rise. The pipe frame 21, spline rod 13 and guide plate 9 fixed to the adjustment frame 11 rise synchronously. The mounting seat 4 at the top of the guide plate 9 adjusts its height accordingly. After the power rod 5 reaches the appropriate drilling height, the first electric hydraulic rod 10 is closed.

[0059] Step 5: Connect the water inlet pipe 31 to the external water supply pipeline and the gas outlet pipe 27 to the gas delivery pipeline. Ensure that all pipeline connections are sealed and check that the one-way valve 45 and the solenoid valve 43 are in normal working condition.

[0060] Step 6: Start motor 14. Motor 14 drives speed regulator 15 through coupling. The first bevel gear 16 on the output shaft of speed regulator 15 meshes with the first bevel gear 16 on spline tube 12, driving spline tube 12 to rotate. Spline rod 13 rotates synchronously with spline tube 12.

[0061] Step 7: The second bevel gear 17 at the top of the spline rod 13 meshes with the second bevel gear 17 on the power rod 5, driving the power rod 5, the extension drill rod and the drill bit to rotate. During the rotation of the drill bit, the equipment is pushed forward along the track to drill into the low-permeability coal seam.

[0062] Step 8: When the spline tube 12 rotates, the third bevel gear 33 on it meshes with the third bevel gear 33 on the rotating rod 29, driving the rotating rod 29 and impeller 30 inside the water guide shell 28 to rotate and generate negative pressure. External water enters the water guide shell 28 through the water inlet pipe 31, and then enters the water channel 6 of the power rod 5 through the first telescopic pipe 22, the double-channel rotary joint 18, and the first connecting pipe 19 in sequence. It then flows out from the drill bit water hole through the drill rod water channel to cool the drill bit.

[0063] Step 9: The two fourth bevel gears 35 on the spline tube 12 mesh with the two fourth bevel gears 35 on the input shaft of the extraction pump 24, driving the extraction pump 24 to run. The gas-liquid mixture in the coal seam enters the extraction pump 24 through the drill bit air hole, drill rod air passage, power rod 5 air passage 7, second connecting pipe 20, double channel rotary joint 18, and second telescopic pipe 23, and is then sent by the extraction pump 24 to the gas-liquid separator 25 through the air guide pipe 26.

[0064] Step 10: The gas-liquid separator 25 separates the gas-liquid mixture. The separated gas is discharged into the gas delivery pipeline through the gas outlet pipe 27, and the separated water flows into the filter 49 through the connecting pipe 39 for filtration.

[0065] Step 11: The filtered water flows through the water guide cavity 37 inside the cooling shell 36 of the pump 24 to cool the pump 24. At the same time, the fan blades 38 on the input shaft of the pump 24 rotate to blow air and accelerate the heat dissipation of the cooling shell 36. The airflow is discharged through the exhaust pipe 40.

[0066] Step 12: After cooling, the water flows through the outlet pipe 42, and the flow rate is controlled by the solenoid valve 43 before flowing into the water collection tank 41. Then, it flows through the drain pipe 44 and the one-way valve 45 into the inlet pipe 31 to achieve recycling.

[0067] Step 13: After the gas extraction is completed, turn off motor 14, reverse the second electric hydraulic rod 46 to make the positioning plate 48 detach from the coal gangue layer, and use steel wire rope to retrieve the equipment along the track to the designated position. Disassemble the drill bit, extend the drill rod and each pipeline to complete the extraction operation.

[0068] In summary, compared with related technologies, by integrating water channels 6 and air channels 7 through the power rod 5, and combining the drive mechanism to drive the coordinated operation of multiple components such as drilling, water supply, and extraction, and with the assistance of adjustment mechanisms, filtration mechanisms, cooling mechanisms, and other components, the equipment achieves stable movement and positioning by relying on the base plate 1, track wheels 2, and positioning mechanism. By using the gas-liquid separator 25, filter 49, and water collection tank 41 to achieve gas-liquid separation and wastewater circulation, the overall adaptability of the equipment to low-permeability coal seams is improved, the number of operation procedures and the risk of borehole collapse are reduced, and efficient extraction of gas from low-permeability coal seams is achieved. At the same time, the equipment structure is simplified, energy consumption is reduced, and the service life of the equipment is extended.

[0069] It is worth noting that the circuits, electronic components, and modules involved in this invention are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated upon. The content protected by this invention does not involve improvements to the software and methods.

[0070] It should be understood, in the several embodiments provided in this application, that the disclosed apparatus may be implemented in other ways.

[0071] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still combine, add, delete, or otherwise adjust the features of the various embodiments of the present invention according to the circumstances without conflict or creative effort, thereby obtaining different technical solutions that do not fundamentally depart from the concept of the present invention. These technical solutions are also within the scope of protection of the present invention.

Claims

1. A low-permeability coal seam gas extraction device, characterized in that, include: Base plate; A housing fixed to the base plate, the housing being equipped with a gas extraction mechanism; The drive mechanism and the filter mechanism are installed inside the housing; The filtration mechanism is used to purify the extracted gas-liquid mixture.

2. The low-permeability coal seam gas extraction equipment as described in claim 1, characterized in that, The sampling mechanism includes: A height-adjustable mounting base is installed on the housing; A power rod is rotatably mounted on the mounting base via a bearing, and the front end of the power rod has a threaded groove for mounting a drill rod. Water and air passages are provided on the power rod.

3. The low-permeability coal seam gas extraction equipment as described in claim 2, characterized in that, The extraction mechanism further includes an adjustment mechanism for adjusting the height of the mounting base, wherein the adjustment mechanism: A partition fixed inside the box, on which a first electro-hydraulic rod is fixed; An adjustment bracket is fixed to the first electric hydraulic rod push rod, and the top of the adjustment bracket is fixedly connected to the corresponding mounting base; A pipe rack fixed on the adjusting frame, and a dual-channel rotary joint fixed on the pipe rack; A second connecting pipe is fixedly connected to the air inlet end of the dual-channel rotary joint; A second telescopic pipe is fixedly connected to the air outlet end of the dual-channel rotary joint; A pumping unit fixed to the partition plate, wherein the air inlet of the pumping unit is fixedly connected to the second telescopic pipe; A guide plate is slidably installed inside the housing, and the top end of the guide plate is fixedly connected to the corresponding mounting base.

4. The low-permeability coal seam gas extraction equipment as described in claim 3, characterized in that, The filtration mechanism includes: A gas-liquid separator fixed on the partition plate; A gas guide pipe is fixedly connected to the gas inlet end of the gas-water separator, and the gas inlet end of the gas guide pipe is fixedly connected to the gas outlet end of the extraction pump. A gas outlet pipe is fixedly connected to the gas outlet end of the gas-water separator and is used to connect to a gas conveying pipeline.

5. The low-permeability coal seam gas extraction equipment as described in claim 4, characterized in that, The drive mechanism includes: The spline tube, which is rotatably mounted inside the housing, is rotatably mounted via a bearing housing. The spline rod, which is mounted on the adjusting frame, is rotated by a bearing, and the bottom end of the spline rod is inserted into the spline tube. The motor and speed controller are fixed inside the housing, and the output shaft of the motor is fixedly connected to the input shaft of the speed controller via a coupling; The first bevel gears, which are respectively fixed to the output shaft of the speed regulator and the spline tube and mesh with each other; A second bevel gear, which is fixed to the spline rod and the power rod respectively and meshes with each other; Two fourth bevel gears are fixed to the spline tube and the input shaft of the extraction pump, respectively, and mesh with each other.

6. The low-permeability coal seam gas extraction equipment as described in claim 5, characterized in that, The tank is equipped with a water supply mechanism for supplying water for drilling. The water supply mechanism includes: A water guide shell fixed inside the box, the water outlet of the water guide shell being fixedly connected to the water inlet of the dual-channel rotary joint through a water guide pipe and a first telescopic pipe; The outlet end of the dual-channel rotary joint is fixedly connected to the waterway through the first connecting pipe; The rotating rod installed inside the water guide shell is rotated by a sealed bearing. The impeller is fixed on the rotating rod; A third bevel gear, which is fixed to the rotating rod and the spline tube respectively and meshes with each other; A water inlet pipe is fixedly connected to the water inlet end of the water guide shell and is used to connect to an external water supply pipeline.

7. The low-permeability coal seam gas extraction equipment as described in claim 1, characterized in that, The housing is equipped with a positioning mechanism, which includes a second electro-hydraulic rod, an assembly plate, and a positioning plate. The second electro-hydraulic rod is fixed inside the housing, and the bottom end of the push rod of the second electro-hydraulic rod is fixedly connected to the assembly plate. The positioning plate is fixed to the bottom of the assembly plate, and its bottom end is conical, which is used to insert into the coal gangue layer to achieve equipment positioning.

8. The low-permeability coal seam gas extraction equipment as described in claim 1, characterized in that, The base plate is fixed with a connecting seat at its tail for installing steel wire rope, and the connecting seat is provided with a pluggable pin.

9. The low-permeability coal seam gas extraction equipment as described in claim 1, characterized in that, The base plate has a base frame symmetrically fixed to its bottom, and a track wheel is rotatably mounted on the base frame for moving along the track.

10. A method for extracting gas from low-permeability coal seams as described in any one of claims 1-9, characterized in that, The method includes the following steps: Step 1: Set the track wheel on the bottom frame of the base plate on the preset track, install the wire rope through the connecting seat at the tail of the base plate and insert the pin to fix it, and use the wire rope to lower the equipment into the inclined mine channel until it reaches the designated extraction point, then stop lowering and fix the rope. Step 2: Install the extension drill rod thread onto the front thread of the power rod, ensuring that the water channel on the drill rod is aligned with the water channel on the power rod and that the air channel on the drill rod is connected to the air channel on the power rod. Then install the drill bit thread with the air and water holes onto the front thread of the extension drill rod. Step 3: Activate the second electro-hydraulic rod, which extends to lower the assembly plate, causing the conical structure at the bottom of the positioning plate at the bottom of the assembly plate to insert into the coal gangue layer. After the equipment is positioned, close the second electro-hydraulic rod. Step 4: Start the first electric hydraulic rod according to the extraction requirements. Its push rod rises and drives the adjustment frame to rise. The pipe rack, spline rod and guide plate fixed to the adjustment frame rise synchronously. The mounting seat at the top of the guide plate adjusts its height accordingly. After the power rod reaches the appropriate drilling height, the first electric hydraulic rod is turned off. Step 5: Connect the water inlet pipe to the external water supply line and the gas outlet pipe to the gas delivery line. Ensure that all pipe connections are sealed and check that the check valve and solenoid valve are in normal working condition. Step 6: Start the motor. The motor drives the speed regulator through the coupling. The first bevel gear on the output shaft of the speed regulator meshes with the first bevel gear on the spline tube, driving the spline tube to rotate. The spline rod rotates synchronously with the spline tube. Step 7: The second bevel gear at the top of the spline rod meshes with the second bevel gear on the power rod, driving the power rod, the extension drill rod and the drill bit to rotate. During the rotation of the drill bit, the equipment is pushed forward along the track to drill into the low-permeability coal seam. Step 8: When the spline tube rotates, the third bevel gear on it meshes with the third bevel gear on the rotating rod, driving the rotating rod and impeller inside the water guide shell to rotate and generate negative pressure. External water enters the water guide shell through the inlet pipe, and then enters the water channel of the power rod through the first telescopic pipe, the double-channel rotary joint, and the first connecting pipe in sequence. It then flows out from the drill bit water hole through the drill rod water channel to cool the drill bit. Step 9: The two fourth bevel gears on the spline tube mesh with the two fourth bevel gears on the input shaft of the extraction pump, driving the extraction pump to run. The gas-liquid mixture in the coal seam enters the extraction pump through the drill bit air hole, drill rod air passage, power rod air passage, second connecting pipe, double-channel rotary joint, and second telescopic pipe, and is then sent to the gas-liquid separator by the extraction pump through the air guide pipe. Step 10: The gas-liquid separator separates the gas-liquid mixture, and the separated gas is discharged into the gas delivery pipeline through the gas outlet pipe; Step 11: After the gas extraction is completed, turn off the motor, reverse the second electric hydraulic rod to detach the positioning plate from the coal gangue layer, and use the wire rope to retrieve the equipment along the track to the designated position. Disassemble the drill bit, extend the drill rod and all pipelines to complete the extraction operation.

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