Gas extraction drilling intelligent plugging-displacement yield increase-redundancy protection integrated device and method

Abstract

The present application relates to coal mine gas extraction technology and equipment technical field, specifically relates to gas extraction drilling intelligent plugging-displacement production-increase redundancy protection integrated equipment and method, the equipment includes carbon dioxide displacement system, grouting system and gas extraction system, intelligent control system, the present application can carry out intelligent plugging to gas extraction drilling, greatly limit the airtightness of drilling is guaranteed, can displace the adsorbed gas in each layer, improve the extraction amount of gas, reduce the gas outburst risk, and increase the redundancy protection such as emergency closure device, increase the safety of extraction equipment. Greatly reduce the cost of manual intervention, improve the sealing effect of drilling plugging, compared with ordinary drilling plugging, improve the gas production, increase the safety of gas extraction operation.

Description

Technical Field

[0001] This invention relates to the field of coal mine gas extraction technology and equipment technology, specifically to an integrated equipment and method for intelligent sealing, displacement and production enhancement, and redundant protection of gas extraction boreholes. Background Technology

[0002] Gas disasters are one of the major threats to coal mine safety in my country. Statistics show that high-gas and coal and gas outburst mines account for over 30% of all coal mines in my country. Gas accidents (such as gas explosions and outbursts) not only cause significant casualties and property damage but also severely restrict efficient coal mining. With increasing mining depth, coal seam gas pressure and content further increase, making gas control more difficult, and traditional prevention and control technologies are no longer sufficient to meet safety requirements. Furthermore, low gas extraction efficiency and poor borehole sealing quality leading to borehole leakage directly affect the extraction concentration and effectiveness. The failure of the explosion-proof performance of gas extraction equipment further exacerbates the safety risks of gas disasters.

[0003] Gas drainage is the core means of controlling gas disasters, mainly including drainage from the coal seam itself, drainage from adjacent seams, and drainage from goaf areas. During borehole drainage, borehole sealing technology has always faced numerous challenges. Sealing quality is a key factor affecting drainage efficiency, and improving gas drainage efficiency and volume is the primary objective. The safety of drainage equipment is paramount, as it concerns the lives and property of underground workers. Currently, commonly used traditional sealing methods include chemical foaming materials, inorganic cementing materials, and mechanical sealing devices. While chemical foaming materials have rapid expansion characteristics and can achieve rapid sealing, incomplete sealing often occurs in practice. Inorganic cementing materials (such as cement) often suffer from leakage channels after hardening due to continuous seepage of coal seam gas during injection, often resulting in failure due to ground stress. Mechanical sealing devices, limited by material properties, are prone to creep failure under complex underground stress environments, and even repeated sealing measures cannot achieve ideal sealing results. While existing dynamic sealing technologies can achieve some response adjustment, they still rely on preset parameters and cannot accurately identify whether gas is leaking based solely on pressure sensors. They lack real-time sensing and intelligent decision-making capabilities and do not have means or methods to promote gas desorption, thus failing to achieve sufficient gas extraction. Furthermore, they lack redundant safety design, and in the event of equipment explosion-proof performance failure, accidents such as gas explosions may occur. Summary of the Invention

[0004] This invention addresses the bottlenecks of traditional plugging technologies, such as poor sealing, frequent manual intervention, insufficient gas extraction, and lack of equipment redundancy protection. It provides an integrated intelligent plugging, displacement, and redundant protection device for gas extraction boreholes. By real-time monitoring of the extracted gas composition and borehole pressure changes, intelligent analysis enables adaptive plugging and intelligent gas displacement, improving borehole sealing and gas extraction efficiency. The designed redundant protection significantly enhances equipment safety, providing an extra layer of protection for extraction safety. This invention enables sufficient gas extraction, significantly improving gas control levels, greatly extending the service life of boreholes, and enhancing the safety of gas extraction equipment, thus achieving intelligent gas extraction.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: an integrated intelligent plugging-displacement-redundant protection device for gas extraction boreholes, including a carbon dioxide displacement system, a grouting system, a gas extraction system, and an intelligent control system;

[0006] The carbon dioxide displacement system includes a carbon dioxide displacement device 1, which is connected to an injection pipe and has a first electric valve installed on the injection pipe. The end of the injection pipe extends to the gas extraction space.

[0007] The grouting system includes a stirable grout storage tank, a cement grout storage tank, and a first and a second slurry bag placed in the borehole. The stirable grout storage tank and the cement grout storage tank are connected in parallel via pipelines connected in series with a second electric valve and a third electric valve, respectively. After being connected in parallel, they are connected in series with a grouting pipe. The grouting pipe passes through the first and second slurry bags, and a burst valve is installed in the grouting pipe located between the two slurry bags. A grouting pressure gauge is also installed on the grouting pipe.

[0008] The gas extraction system includes a gas extraction pipeline, the end of which extends into the gas extraction space. The gas extraction pipeline is also connected in series with a gas extraction pump, a multi-component gas analyzer, and an emergency sealing device. The multi-component gas analyzer has a CH4 concentration sensor, a CO2 concentration sensor, an O2 concentration sensor, and an N2 concentration sensor.

[0009] The intelligent control system includes an intelligent control platform. The gas extraction pump, multi-component gas analyzer, emergency sealing device, first electric valve, second electric valve, third electric valve, and grouting pressure gauge are all electrically connected to the intelligent control platform. The intelligent control platform includes an electric valve control module, an RTU control module, and a data visualization module. The electric valve control module controls all on / off valves. The RTU control module collects monitoring data of various gases, makes corresponding judgments, and feeds back to the electric valve control module. The data visualization module collects gas concentration change data and generates a gas concentration decay map. The multi-component gas analyzer collects gas component data in the gas extraction pipeline and transmits it to the intelligent control platform.

[0010] As a further limitation of the technical solution of the present invention, the top of the stirable slurry storage tank is provided with a slurry injection port, and the interior of the stirable slurry storage tank is equipped with stirring fan blades.

[0011] As a further limitation of the technical solution of the present invention, one-way grouting valves are respectively installed on the pipelines connecting the grouting pipe to the first bladder and the second bladder.

[0012] As a further limitation of the technical solution of the present invention, the measurement range of the O2 concentration sensor is 0-10% for explosion-proof safety monitoring, the measurement range of the CH4 concentration sensor is 0-100% for judging changes in gas extraction concentration, the measurement range of the N2 concentration sensor is 0-100% but mainly for indirect measurement, and the measurement range of the CO2 concentration sensor is 0-10% to avoid errors caused by low precision.

[0013] This invention also provides an integrated method for intelligent plugging, displacement and production enhancement, and redundant protection of gas extraction boreholes, using the aforementioned equipment, and comprising the following steps:

[0014] Step 1, Burr Bag Sealing Stage: First, drill holes and check the grouting pipe, air injection pipe, gas extraction pipe, and pressure sensor for integrity. Then, place the sealing equipment into the hole in sequence. Put cement mortar into the cement storage tank. The intelligent control platform opens the third electric valve and injects cement mortar into the first and second burr bags through the grouting pump. Observe the grouting pressure gauge. When the pressure reaches 3MPa, stop grouting. After the pressure stabilizes for two minutes, close the third electric valve and detonate the blasting valve first. The intelligent control platform opens the second electric valve to inject a certain amount of non-condensable fluid to push the remaining cement mortar in the grouting pipe into the borehole to prevent the pipe from being blocked by cement mortar. Then, let it stand for 10-12 hours to wait for the cement mortar in the burr bags to solidify.

[0015] Step 2, Non-condensable fluid sealing stage: After the cement mortar in the sump has solidified, add the pre-mixed non-condensable fluid or constituent materials to the stirable slurry storage tank, and start the stirring to continuously stir the grouting material. Open the second electric valve and inject the non-condensable fluid into the borehole through the grouting pump. At the same time, observe the pressure change in the borehole fed back by the grouting pressure gauge. When the grouting pressure reaches 1.5 to 2 times or 2 to 3 MPa of the coal seam gas pressure and is maintained stably for 3 to 5 minutes, the grouting can be stopped. At this time, the gas extraction pump is turned on to extract the gas.

[0016] Step 3, S1 Intelligent Sealing: The RTU control module of the intelligent control platform monitors and analyzes the concentration of each component in the extracted gas in real time. When the oxygen concentration in the extracted gas increases significantly, and the gas concentration decreases slowly but is not zero, it can be determined that there is air leakage in the borehole. The intelligent control platform controls the opening of the second electric valve and continues to inject sealing grout into the grout penetration zone through the grouting pump until it reaches 1.5 to 2 times the coal seam gas pressure. Then, the valve control module closes the second electric valve to stop grouting. S2 Displacement and Production Enhancement: When the oxygen concentration in the extracted gas does not change, but the gas concentration gradually decreases until it reaches zero, the intelligent control platform can determine that gas extraction is complete and shuts off the gas extraction pump. The electric valve control module opens the first electric valve to inject sealing grout into the coal seam. A certain amount of carbon dioxide is injected into the gas extraction space, with the injection amount depending on the volume of the coal seam, to displace the methane in the coal seam. After standing for 4-6 hours, the gas extraction pump is restarted to fully extract the desorbed gas. S3 redundancy protection: When the oxygen concentration in the extracted gas reaches 7% or more, while grouting and sealing, the intelligent control platform opens the first electric valve to inject carbon dioxide to reduce the oxygen concentration to a safe range, ensuring that the oxygen is controlled at a safe concentration before the sealing is completed. If the oxygen concentration continues to rise to 10% or more, it indicates that the sealing has failed, and the gas extraction pump is shut down. Since the gas extraction pump will continue to extract for a period of time after power failure, the emergency sealing device is immediately controlled to stop the gas extraction in an emergency to ensure the safety of gas extraction.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Redundant Safety Protection: Traditional technologies lack proactive safety response mechanisms. This invention constructs multiple layers of protection: an emergency sealing device quickly cuts off abnormal operating conditions (oxygen concentration reaches 10% or higher, close to the oxygen concentration required for a gas explosion), and injects carbon dioxide to reduce the oxygen concentration (when the oxygen concentration reaches 7% or higher, and before the intelligent grouting completely seals the air leakage gap). In the event of equipment explosion-proof performance failure, the gas concentration is controlled within a safe range, increasing the safety of the sealing equipment.

[0019] 2. Intelligent displacement and gas extraction synergistic optimization: Traditional methods lack gas production enhancement measures. This invention innovatively integrates carbon dioxide displacement equipment, which automatically switches gas injection based on changes in gas concentration through an intelligent control platform. This can not only enhance gas desorption efficiency and increase gas production and profits, but also reduce the risk of explosion by diluting gas and oxygen concentrations.

[0020] 3. Intelligent judgment and analysis: By observing the real-time changes in gas decay and gas composition concentration, it is possible to determine whether the gas decay is due to the exhaustion of gas extraction or to air leakage in the borehole. Intelligent control can be implemented to prevent the gas extraction pump from performing ineffective extraction and reduce the consumption of ineffective energy.

[0021] 4. Multifunctional material and structural design: The system adopts a dual-tank parallel system of "non-solid sealing material + cement grouting", combined with the design of unidirectional grouting port and burst valve of the bladder bag. This ensures both initial rapid sealing (bladder bag expansion) and continuous replenishment of non-solid material through the stirable grout storage tank, solving the problems of shrinkage, rupture and air leakage of traditional solidified materials.

[0022] 5. Intelligent and Visualized: The intelligent control platform integrates RTU data acquisition, gas decay display charts, and automatic valve control, enabling fully automated operation from grouting and displacement to extraction, significantly reducing labor costs and improving gas utilization and extraction volume. Furthermore, it visualizes gas decay trends through real-time curves, allowing for automatic control triggered by preset parameters, whereas traditional techniques rely on manual experience.

[0023] 6. Dynamic adaptive control capability: Ordinary technologies rely on manual judgment or equipment such as pressure sensors, while this invention uses real-time data feedback from a multi-component gas analyzer (CH4 / CO2 / O2 / N2) combined with algorithm analysis from an intelligent control platform to dynamically adjust the grouting volume and the amount of carbon dioxide injected as displacement gas. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the integrated intelligent plugging, displacement and production enhancement, and redundancy protection equipment for gas extraction boreholes according to the present invention.

[0025] Figure 2 This is a schematic diagram of the internal components of the intelligent control platform of the present invention.

[0026] Figure 3 This is a schematic diagram of the internal components of the multi-gas component analyzer of the present invention.

[0027] Figure 4 This is a partially enlarged schematic diagram of the grouting pipe of the present invention.

[0028] The markings in the image are as follows:

[0029] 1-Carbon dioxide displacement device; 2-Gas extraction space; 3-Stirred slurry storage tank; 4-Cement slurry storage tank; 5-Grouting port; 601-First electric valve; 602-Second electric valve; 603-Third electric valve; 7-Grouting pump; 8-Gas injection pipe; 9-Intelligent control platform; 10-Gas extraction pump; 11-Multi-component gas analyzer; 12-Emergency sealing device; 13-Grouting pipe; 14-Gas extraction pipeline; 15-First bladder; 16-Second bladder; 17-Grouting pressure gauge; 18-Slurry permeation zone; 19-Electric valve control module; 20-RTU control module; 21-Gas attenuation visualization module; 22-One-way grouting valve; 23-Explosion valve; 24-CH4 concentration sensor; 25-CO2 concentration sensor; 26-O2 concentration sensor; 27-N2 concentration sensor; 28-Stirring fan blade. Detailed Implementation

[0030] The present invention will be further described below with reference to specific embodiments. Example 1

[0031] like Figure 1 As shown, an integrated intelligent plugging-displacement-redundant protection device for gas extraction boreholes includes a carbon dioxide displacement system, a grouting system, a gas extraction system, and an intelligent control system.

[0032] The carbon dioxide displacement system includes a carbon dioxide displacement device 1, which is connected to an injection pipe 8 and a first electric valve 601 is installed on the injection pipe 8. The end of the injection pipe 8 extends to the gas extraction space 2. When the oxygen concentration of the extracted gas remains constant and the gas concentration continues to decrease and approaches zero, the intelligent control platform 9 can determine that the gas extraction is complete and can start the electric valve to inject carbon dioxide to displace the gas, so as to achieve the effect of full extraction.

[0033] The grouting system includes a stirable grout storage tank 3, a cement grout storage tank 4, and a first bag 15 and a second bag 16 placed in the borehole. The stirable grout storage tank 3 and the cement grout storage tank 4 are connected in parallel via pipelines connected in series with a second electric valve 602 and a third electric valve 603, respectively. After being connected in parallel, they are connected in series with a grouting pipe 13. The grouting pipe 13 passes through the first bag 15 and the second bag 16. The end port of the grouting pipe 13 is in a closed state, and a burst valve 23 is installed in the grouting pipe located between the two bags. A grouting pressure gauge 17 is also installed on the grouting pipe 13.

[0034] The gas extraction system includes a gas extraction pipeline 14, the end of which extends into the gas extraction space 2. The gas extraction pipeline 14 is also connected in series with a gas extraction pump 10, a multi-component gas analyzer 11, and an emergency sealing device 12. When the oxygen concentration exceeds the limit and reaches an explosion hazard level, the extraction pipeline can be blocked immediately to improve equipment safety. It can also immediately close the pipeline and prevent gas from entering the extraction pump 10 if the residual power is maintained after the gas extraction pump is powered off. The multi-component gas analyzer 11 internally includes a CH4 concentration sensor 24, a CO2 concentration sensor 25, an O2 concentration sensor 26, and an N2 concentration sensor 27 (e.g., CH4 concentration sensor 24, CO2 concentration sensor 25, O2 concentration sensor 26, N2 concentration sensor 27, etc.). Figure 3 (As shown); if during the extraction process, the multi-component gas analyzer 11 detects that the oxygen concentration is above 7% or even higher, in order to reduce the risk of explosion, the intelligent control platform opens the first moving valve 601 to inject carbon dioxide, reduce the oxygen concentration to a safe range, prevent gas explosion, and increase pressure to accelerate the extraction rate.

[0035] The intelligent control system includes an intelligent control platform 9. The gas extraction pump 10, multi-component gas analyzer 11, emergency sealing device 12, first electric valve 601, second electric valve 602, third electric valve 603, and grouting pressure gauge 17 are all electrically connected to the intelligent control platform 9. Figure 2 As shown, the intelligent control platform 9 includes an electric valve control module 19, an RTU control module 20, and a data visualization module 21. The electric valve control module 19 controls all on / off valves. The RTU control module 20 collects monitoring data of various gases, makes corresponding judgments, and feeds them back to the electric valve control module 19. The data visualization module 21 collects gas concentration change data and generates a gas concentration decay chart to ensure the efficiency and safety of gas extraction. The multi-component gas analyzer 11 collects gas component data in the gas extraction pipeline 14 and transmits it to the visualization module 21 inside the intelligent control platform 9. After processing the data, the module can draw a gas concentration decay chart and visualize the gas decay trend through real-time curves.

[0036] Furthermore, the top of the stirable slurry storage tank 3 is provided with a slurry inlet 5, and the interior of the stirable slurry storage tank 3 is equipped with a stirring fan blade 28, which can stir the injected slurry in real time and mix the put-in slurry raw materials evenly.

[0037] Furthermore, such as Figure 4 As shown, one-way grouting valves 22 are installed on the pipelines connecting the grouting pipe 13 to the first bladder 15 and the second bladder 16, respectively.

[0038] Furthermore, the O2 concentration sensor 26 has a measurement range of 0-10% for explosion-proof safety monitoring, the CH4 concentration sensor 24 has a measurement range of 0-100% for judging changes in gas extraction concentration, the N2 concentration sensor 27 has a measurement range of 0-100% but is mainly used for indirect measurement, and the CO2 concentration sensor 25 has a measurement range of 0-10% to avoid errors caused by low precision. Example 2

[0039] A method for intelligent plugging, displacement and production enhancement, and redundant protection of gas extraction boreholes, using the equipment described in Example 1 above, includes the following steps:

[0040] Step 1, Sealing the Bags: First, drill holes and check the grouting pipe 13, air injection pipe 8, gas extraction pipe 14, and pressure sensor for integrity. Then, place the sealing equipment into the holes one by one. Put cement mortar into the cement storage tank 4. The intelligent control platform 9 controls the opening of the third electric valve 603. The cement mortar is injected into the first bag 15 and the second bag 16 through the grouting pump 7. The one-way grouting valve 22 prevents the injected cement mortar from flowing back into the grouting pipe. Observe the grouting pressure gauge 17. When the pressure reaches 3MPa, stop grouting. After the pressure stabilizes for two minutes, close the third electric valve 603. Detonate the blasting valve 23 first. The intelligent control platform 9 opens the second electric valve 602 to inject a certain amount of non-condensable fluid to push the remaining cement mortar in the grouting pipe into the borehole to prevent the pipe from being blocked by cement mortar. Then, let it stand for 10-12 hours to wait for the cement mortar in the bags to solidify.

[0041] Step 2, Non-condensable fluid sealing stage: After the cement mortar in the bladder has solidified, add the pre-mixed non-condensable fluid or constituent materials to the stirable slurry storage tank 3, and start the stirring to continuously stir the grouting material. Open the second electric valve 602 and inject the non-condensable fluid into the borehole through the grouting pump 7. At the same time, observe the pressure change in the borehole fed back by the grouting pressure gauge 17. When the grouting pressure reaches 1.5 to 2 times or 2 to 3 MPa of the coal seam gas pressure and is maintained stably for 3 to 5 minutes, the grouting can be stopped. At this time, the gas extraction pump is turned on to extract the gas.

[0042] Step 3, S1 Intelligent Sealing: The RTU control module 20 of the intelligent control platform 9 monitors and analyzes the concentration of each component in the extracted gas in real time. When the oxygen concentration in the extracted gas increases significantly and the gas concentration decreases slowly but is not zero, it can be determined that there is air leakage in the borehole. The intelligent control platform 9 controls the opening of the second electric valve 602 and continues to inject sealing grout into the grout penetration zone through the grouting pump until it reaches 1.5 to 2 times the coal seam gas pressure. Then, the valve control module closes the second electric valve 602 to stop grouting. S2 Displacement and Production Increase: When the oxygen concentration in the extracted gas does not change, but the gas concentration gradually decreases until it reaches zero, the intelligent control platform can determine that the gas extraction is complete and closes the gas extraction pump 10. The electric valve control module 19 opens the first electric valve 601. A certain amount of carbon dioxide is injected into the gas extraction space 2, with the injection amount depending on the volume of the coal seam, to displace the methane in the coal seam. After standing for 4-6 hours, the gas extraction pump 10 is restarted to fully extract the desorbed gas. S3 Redundancy Protection: When the oxygen concentration in the extracted gas reaches 7% or more, while grouting and sealing, the intelligent control platform 9 opens the first electric valve 601 to inject carbon dioxide to reduce the oxygen concentration to a safe range, ensuring that the oxygen is controlled at a safe concentration before the sealing is completed. If the oxygen concentration continues to rise to 10% or more, it indicates that the sealing has failed, and the gas extraction pump 10 is shut down. Since the gas extraction pump 10 will continue to extract for a period of time after power failure, the emergency sealing device 12 is immediately controlled to stop the gas extraction in an emergency to ensure the safety of gas extraction.

[0043] The scope of protection of this invention is not limited to the above embodiments. Any equivalent substitutions, technical improvements, simple modifications, or adaptive adjustments made based on the core technical solutions of this invention, as long as they do not depart from the design principles and technical concepts of this invention, shall be considered reasonable extensions of this invention and shall be included within the patent protection scope of this invention. It is hereby declared that any unauthorized imitation or substantial application constitutes infringement.

Claims

1. A gas extraction drilling intelligent plugging-displacement stimulation-redundancy protection integrated device, characterized in that, The system comprises a carbon dioxide displacement system, a grouting system, a gas extraction system and an intelligent control system. The carbon dioxide displacement system comprises a carbon dioxide displacement device (1), an injection pipe (8) connected to the carbon dioxide displacement device (1), and a first electric valve (601) installed on the injection pipe (8). The grouting system comprises a stirrable grouting tank (3), a cement grouting tank (4), a first bag (15) and a second bag (16) placed in a borehole, the stirrable grouting tank (3) and the cement grouting tank (4) are connected in parallel through a pipeline, and a second electric valve (602) and a third electric valve (603) are connected in series to the pipeline, the pipeline connected in parallel is connected in series to a grouting pipe (13), the grouting pipe (13) passes through the first bag (15) and the second bag (16), and a blasting valve (23) is arranged in the grouting pipe between the two bags, and a grouting pressure gauge (17) is installed on the grouting pipe (13). The gas extraction system comprises a gas extraction pipeline (14), the end of the gas extraction pipeline (14) extends to a gas extraction space (2), and the gas extraction pipeline (14) is connected in series to a gas extraction pump (10), a multi-component gas analyzer (11) and an emergency closure device (12), the multi-component gas analyzer (11) has a CH4 concentration sensor (24), a CO2 concentration sensor (25), an O2 concentration sensor (26) and an N2 concentration sensor (27) arranged therein. The intelligent control system comprises an intelligent control platform (9), the gas extraction pump (10), the multi-component gas analyzer (11), the emergency closure device (12), the first electric valve (601), the second electric valve (602), the third electric valve (603) and the grouting pressure gauge (17) are electrically connected to the intelligent control platform (9), the intelligent control platform (9) comprises an electric valve control module (19), an RTU control module (20) and a data visualization module (21), the electric valve control module (19) is used for controlling all on-off valves, the RTU control module (20) collects monitoring data of various gases, makes corresponding judgments and feeds back to the electric valve control module (19), and the data visualization module (21) collects gas concentration change data and generates a gas concentration decay graph, and the multi-component gas analyzer (11) collects gas component data in the gas extraction pipeline (14) and transmits the data to the intelligent control platform (9).

2. The gas extraction drilling intelligent plugging-displacement stimulation-redundancy protection integrated device according to claim 1, characterized in that, A grouting port (5) is arranged on the top of the stirrable grouting tank (3), and a stirring fan blade (28) is arranged in the stirrable grouting tank (3).

3. The gas extraction drilling intelligent plugging-displacement stimulation-redundancy protection integrated device according to claim 1, characterized in that, A one-way grouting valve (22) is arranged on the pipeline connecting the grouting pipe (13) with the first bag (15) and the second bag (16).

4. The gas extraction drilling intelligent plugging-displacement stimulation-redundancy protection integrated device according to claim 1, characterized in that, The measurement range of the O2 concentration sensor (26) is 0-10% for explosion-proof safety monitoring, the measurement range of the CH4 concentration sensor (24) is 0-100% for judging the concentration change of gas extraction, the measurement range of the N2 concentration sensor (27) is 0-100% for indirect measurement, and the measurement range of the CO2 concentration sensor (25) is 0-10%.

5. A gas extraction drilling intelligent plugging-displacement stimulation-redundancy protection integrated method, using the device of any one of claims 1-4, characterized in that, The method comprises the following steps: Step one, bag hole sealing stage: first, drill a hole, check whether the grouting pipe (13), gas injection pipe (8), gas extraction pipeline (14) and pressure sensor are intact, then put the hole sealing equipment into the hole in turn; put the cement mortar into the cement storage tank (4), open the third electric valve (603) of the intelligent control platform (9), inject the cement mortar into the first bag (15) and the second bag (16) through the grouting pump (7), observe the grouting pressure gauge (17), stop grouting when the pressure reaches 3MPa, close the third electric valve (603) after two minutes of pressure stabilization, first detonate the blasting valve (23), open the second electric valve (602) of the intelligent control platform (9) to inject a certain amount of non-condensable fluid to push the residual cement slurry in the grouting pipe into the hole to prevent the pipeline from being blocked by the cement mortar, then stand by for 10-12 hours to wait for the solidification of the cement mortar in the bag; Step two, non-condensable fluid sealing stage: after the solidification of the cement mortar in the bag, supplement the non-condensable fluid or component materials prepared in advance into the stirrable storage tank (3), and start stirring the grouting material continuously, open the second electric valve (602) to inject the non-condensable fluid into the hole through the grouting pump (7), and observe the pressure change in the hole fed back by the grouting pressure gauge (17), stop grouting when the grouting pressure reaches 1.5-2 times or 2-3 MPa of the coal seam gas pressure and is stable for 3-5 minutes, at this time, open the gas extraction pump for gas extraction; Step three, S1 intelligent plugging: the RTU control module (20) of the intelligent control platform (9) detects and analyzes the concentration of each component of the extracted gas in real time. When the concentration of oxygen in the extracted gas increases significantly, and the gas concentration slowly decreases but is not zero, it can be judged that the drilling leaks. The intelligent control platform (9) controls to open the second electric valve (602) to continue injecting sealing slurry into the slurry permeation area to 1.5-2 times of the coal seam gas pressure through the grouting pump, and then the valve control module closes the second electric valve (602) to stop grouting; S2 displacement and yield increase: when the oxygen concentration in the extracted gas does not change, but the gas concentration gradually decreases to zero, the intelligent control platform can determine that the gas extraction is complete, and the gas extraction pump (10) is closed. The electric valve control module (19) opens the first electric valve (601) to inject a certain amount of carbon dioxide into the gas extraction space (2). The injection amount of carbon dioxide is referred to the volume of the coal seam, and the methane in the coal seam is displaced. After 4-6 hours, restart the gas extraction pump 10 to fully extract the desorbed gas; S3 redundancy protection: when the oxygen concentration in the extracted gas reaches 7% or more, while grouting and plugging, the intelligent control platform (9) opens the first electric valve (601) to inject carbon dioxide to reduce the oxygen concentration to a safe range, ensuring that the oxygen concentration is controlled within a safe range before plugging is completed. If the oxygen concentration continues to rise to 10% or more, it means that the plugging has failed, so the gas extraction pump (10) is turned off. Since the gas extraction pump (10) will still maintain a certain amount of power for a period of time after being powered off, the emergency sealing device (12) is immediately controlled to stop gas extraction to ensure the safety of gas extraction.

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