A method for preventing and treating gob air leakage in 2GN00 mining method based on steam mist gel

Abstract

The present application relates to the technical field of coal mine safety, in particular to a method for preventing and treating air leakage in goaf of 2GN00 mining method based on steam mist gel. The method uses the characteristics of air flow migration along the air leakage channel, takes air leakage as the carrier, uses different pipelines and nozzles of the spraying device to transport atomized materials A and B into the goaf formed after the 2GN00 mining method, and the two materials react in the goaf and the air leakage channel to block the pores of coal and adhere to the surface of coal and rock body, and crosslink into gel on the surface to form a covering film, reducing the contact between active groups in coal and oxygen to achieve the purpose of precise plugging. The method of the present application not only facilitates the plugging, but also improves the precision of the plugging.

Description

Technical Field

[0001] This invention relates to the field of coal mine safety materials technology, specifically to a method for preventing air leakage in goaf areas based on vaporized gel in the 2GN00 method. Background Technology

[0002] Spontaneous combustion of coal poses a serious threat to safe production in mines, and filling and sealing leaks is a key technology for preventing spontaneous combustion. Currently, mine fracture sealing technology can be divided into roadway fracture sealing technology and goaf sealing technology, depending on the location. Roadway fracture sealing mainly involves spraying sealing materials, which are primarily divided into two categories: inorganic and organic. Inorganic materials mainly include concrete, cement mortar, fly ash, and gels, etc. Using inexpensive inorganic filling and sealing materials is advantageous due to their low price and wide availability. However, most inorganic materials lack toughness and are easily broken by changes in mine pressure, forming air leakage channels and making it difficult to achieve long-term air sealing.

[0003] Compared to inorganic filling and sealing materials, organic polymer filling and sealing materials offer advantages such as controllable curing time, expandability, good airtightness, and the ability to withstand certain rock movement, demonstrating superior performance. However, existing polymer foam materials release a large amount of heat during the filling process, which can easily trigger secondary disasters.

[0004] Neither of the aforementioned types of materials can meet the sealing requirements of "2GN00" pillarless forward mining. This is because the roadways formed by roof cutting or backfilling are easily affected by repeated mining activities, leading to difficulties in roof and side wall connections. Furthermore, the roadway walls are often cracked and deformed, causing the materials attached to the walls to detach or crack, resulting in new air leakage channels. Repeated spraying is required to solve the air leakage problem, making thorough sealing from the outside of the goaf increasingly difficult. Conversely, if the air leakage problem in the goaf is solved, even if cracks occur in the roadways, the air leakage in the goaf will not increase, thus reducing the probability of spontaneous combustion in the goaf. Therefore, preventing or reducing goaf air leakage is fundamental to solving the fire hazards of "2GN00" pillarless forward mining.

[0005] The main technologies for preventing and controlling leakage in goaf areas include grouting (gel injection), foam injection, and spraying inhibitors. While grouting is low-cost, it is prone to "grooving" and cannot cover a large area of ​​the goaf, nor can it be easily deposited at higher elevations. Foam materials, due to their wide diffusion range, good stacking properties, and ability to cover residual coal at higher elevations, are considered the most suitable technology for preventing spontaneous combustion of coal in goaf areas. However, traditional water-based foam and three-phase foam fire extinguishing materials are prone to rupture and have poor long-term oxygen-barrier effects. Furthermore, the construction methods of the above-mentioned prevention and control technologies make it difficult to achieve precise leakage sealing using airflow. Therefore, these technologies cannot meet the requirements for precise leakage sealing and prevention of spontaneous combustion of coal under pillarless forward mining conditions. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel, thereby solving at least one problem in the background art. The technical solution adopted is as follows:

[0007] A method for preventing air leakage in goaf using the 2GN00 construction method based on aerosol gel. The construction method uses the air leakage in the goaf as a carrier, atomizes the atomizable material and delivers it to the goaf, where it adheres to the surface of the coal and rock mass in the goaf and the air leakage channel, and cross-links into a gel on the surface to form a covering film, thereby achieving the purpose of precise leak sealing.

[0008] Specifically, the following steps are included:

[0009] In the first stage, during the mining process using the 2GN00 method, atomizable materials A and B are sprayed into the unsealed goaf area behind the coal mining support using a spraying device installed on the coal mining support. The atomizable materials diffuse and mix with the airflow. Materials A and B react during the transport and mixing process to form a vapor gel material, which cross-links into a film in the pores and surface of the residual coal, forming a leak-proof layer on the surface of the residual coal in the goaf.

[0010] In the second stage, after the roof is cut to form a roadway and the overlying rock strata of the goaf collapse, atomizable materials A and B are sprayed in the air intake roadway using the reserved spray holes. Atomizable materials A and B enter the goaf through the air leakage channel and are deposited and reacted again in the air leakage channel and goaf to cross-link into a film, forming a plugging layer.

[0011] In the third stage, after the goaf is fully compacted and stabilized, sulfur hexafluoride is used to determine the air leakage channel. Atomizable materials A and B are sprayed at the windward side of the air leakage channel using pre-reserved spray holes, and the airflow is used to transport the atomizable materials into the cracks. Materials A and B gradually deposit and cross-link to form a film to form a leak-stopping layer.

[0012] Preferably, in the first stage, the spraying devices are arranged as follows: a set of spraying devices is arranged every other support near the end of the air intake side, each set including two nozzles, namely the first nozzle and the second nozzle, which spray materials A and B respectively; a set of spraying devices is arranged every two supports in the middle of the coal mining face; and a set of spraying devices is arranged every four supports near the end of the return air side.

[0013] Preferably, in the second stage, the spray holes are arranged as follows: after the top is cut to form the tunnel, a spray hole is reserved every 30 meters at the top of the tunnel.

[0014] Preferably, the spraying device is a high-pressure spraying device, driven by high-pressure nitrogen gas, with a spray pressure of 7-12 MPa, an inclination angle of 52.5-60°, and a spray distance of 6-12 m.

[0015] Preferably, in the first stage, a flexible windbreak curtain is installed at the upper corner of the return air side of the working face to reduce the escape of atomized material into the return airway with the airflow.

[0016] Preferably, the flexible windbreak curtain is a duct cloth, which is divided into strips and suspended at the top of the roof anchor rod, so as not to hinder normal ventilation.

[0017] Preferably, the atomizable material includes material A and material B; wherein, material A includes an organic small molecule monomer with cross-linking film-forming function, a substance containing phenolic hydroxyl groups, an initiator, a surfactant, and water, and material B includes a cross-linking agent, an initiator, a surfactant, and water; materials A and B are mixed and reacted to form an atomized gel material with precise leak-sealing function.

[0018] As a further preferred design, the preparation and application method of the aforementioned vapor gel material with precise leak-sealing function are as follows:

[0019] (1) First, take 7-9 parts of organic small molecule monomer material and surfactant and add them to 5-10 parts of water. Then, add 0.5-1 parts of initiator to the above solution and stir at room temperature for 10-30 minutes. Finally, add 0.5-1.0 parts of substance containing phenolic hydroxyl groups and stir for 10 minutes to form material A.

[0020] (2) Add 0.5-1 part of crosslinking agent, 0.1-0.5 part of initiator and 0.5-1 part of surfactant to 100 parts of water and stir slowly for 10 minutes to obtain material B;

[0021] (3) Materials A and B are sprayed out using different nozzles of a spraying device. A and B react during the transport and mixing process to obtain the vapor gel material.

[0022] (4) In use, material A is transported to the first gas-liquid mixer via a high-pressure dual-liquid transfer pump and a first one-way valve. Then, the high-pressure gas generated by the mobile nitrogen generator is used to transport material A in the first gas-liquid mixer to the first nozzle of the spray device, where it is sprayed out. Simultaneously, material B is transported to the second gas-liquid mixer via a high-pressure dual-liquid transfer pump and a second one-way valve. Then, the high-pressure gas generated by the mobile nitrogen generator is used to transport material B in the second gas-liquid mixer to the second nozzle of the spray device, where it is sprayed out. During the transport and mixing process, materials A and B react and cross-link to form a film on the surface and pores of the residual coal, forming a sealing layer. The high-pressure dual-liquid transfer pump, the mobile nitrogen generator, and the gas-liquid mixer are used to atomize materials A and B.

[0023] Preferably, the organic small molecule monomer with cross-linking film-forming function in material A is one or more of acrylic acid, polyvinyl alcohol, sodium alginate and their compound materials; the substance containing phenolic hydroxyl groups is monophenolic, bisphenolic, and polyphenolic; the initiator is a peroxide, and is one or a mixture of two of ammonium persulfate and sodium persulfate; the surfactant is OP-10.

[0024] As a further preferred embodiment, the organic small molecule monomer with cross-linking film-forming function is acrylic acid; the substance containing phenolic hydroxyl groups is catechol.

[0025] Preferably, the crosslinking agent in material B is sodium carboxymethyl cellulose or polysaccharide, the toughening agent is dodecyl glycoside, and the surfactant is sodium dodecylbenzenesulfonate and OP-10, or a mixture of two of them.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] To address the challenges of preventing and controlling large air leaks and numerous fissures in goaf areas formed by the 2GN00 method of forward coal mining, this invention provides a method for preventing air leaks in 2GN00 goaf areas based on aerosol gel. Utilizing the characteristic of airflow transport along the leak channels, the method uses airflow to carry atomizable materials into the leak channels for deposition, cross-linking, and film formation to seal the leaks, achieving precise sealing. The construction method of this invention is not only convenient but also improves the accuracy of sealing. Attached Figure Description

[0028] Figure 1 This is a cross-sectional view of the construction in the first stage of this invention;

[0029] Figure 2 This is a construction diagram of the first stage of the present invention;

[0030] Figure 3 This is a schematic diagram of the entire construction process of the present invention;

[0031] Figure 4 This is an enlarged view of the material pumping section of the present invention.

[0032] Figure 5 This is a diagram showing the film-forming effect of the atomizable material of the present invention after it is sprayed out.

[0033] In the diagram: 1-Container, 1-1, First Container, 1-2, Second Container; 2-Atomizable Material, 2-1, Material A, 2-2, Material B; 3-High-Pressure Dual-Liquid Transfer Pump; 4-1, First Check Valve, 4-2, Second Check Valve; 5-Mobile Nitrogen Generator; 6-1, First Gas-Liquid Mixer, 6-2, Second Gas-Liquid Mixer; 7-Spraying Device, 7-1, First Nozzle, 7-2, Second Nozzle; 8-Ground Goaf, 8-1, Non-Collapsed Area of ​​Ground Goaf, 8-2, Collapsed Area of ​​Ground Goaf, 8-3, Compacted Area of ​​Ground Goaf; 9-Flexible Windbreak Curtain; 10-Coal Seam; 11-Spray Hole. Detailed Implementation

[0034] The accompanying drawings are for illustrative purposes only; it should be understood that the examples mentioned below are merely for explaining the present invention, in order to facilitate the description of the present invention and simplify the description, and therefore should not be construed as limiting the present invention.

[0035] The principles and features of the present invention are described below with reference to embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer should be followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0036] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0037] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0038] Example 1

[0039] like Figure 1-4 As shown, a method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel includes the following steps:

[0040] In the first stage, during the mining of coal seam 10 using the 2GN00 method, a set of spray devices 7 is arranged every other support on the air intake side, every two supports in the middle of the coal mining face, and every four supports near the return air side. Each set of spray devices 7 includes two nozzles: the first nozzle 7-1 and the second nozzle 7-2. Then, material A2-1 in container 1-1 is transported to the first gas-liquid mixer 6-1 via the high-pressure dual-liquid transfer pump 3 and the first one-way valve 4-1. The high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the first gas-liquid mixer 6-1 to the first nozzle 7-1 in the spray device 7, and the first nozzle 7-1 is used to spray into the non-collapsed area 8-1 of the goaf. At the same time, material B2-2 in container 1-2 is transported to the second gas-liquid mixer 6-2 via the high-pressure dual-liquid transfer pump 3 and the second one-way valve 4-2. The high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the second gas-liquid mixer 6-2 to the second nozzle 7-2 in the spray device 7, and the second nozzle 7-2 is used to spray into the non-collapsed area 8-1 of the goaf. During the transport and mixing process, materials A and B react to form atomizable materials, which are diffused and deposited with the airflow, cross-linking into a film on the surface and pores of the residual coal, thereby forming a plugging layer on the surface of the residual coal in the goaf 8. Meanwhile, a flexible windbreak curtain 9 is installed on the return air side of the working face to prevent materials from entering the return airway with the airflow;

[0041] In the second stage, after the roof is cut to form a roadway and the overlying rock strata of the goaf 8 collapse, the atomizable material 2 in container 1 is transported to the gas-liquid mixer 6 through a high-pressure double-liquid transfer pump 3 and a one-way valve. Then, the high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the materials A and B in the gas-liquid mixer to the spraying device 7. The spraying device 7 sprays the atomizable material into the goaf collapse area 8-2 through the reserved spray holes 11. The materials A and B are deposited and cross-linked into a film again in the air leakage channel and the goaf to form a leak-blocking layer.

[0042] In the third stage, after the goaf 8 is completely stabilized, sulfur hexafluoride is used to determine the air leakage channel. Atomizable materials A and B are sprayed on the windward side of the air leakage channel using a spraying device 7. The airflow is used to transport the atomizable materials A and B to the cracks in the compacted zone 8-3 of the goaf, where they are gradually deposited and cross-linked to form a sealing layer.

[0043] The atomizable material 2 used is an aerosol gel material with precise leak-sealing function. It is prepared by mixing materials A 2-1 and B 2-2 after atomization. The preparation method includes the following specific steps:

[0044] (1) Preparation of material A 2-1: Weigh 5 parts of deionized water at room temperature and add it to the first container 1-1. Then weigh 7 parts of organic small molecule monomer (acrylic acid) and 0.5 parts of surfactant and add them to the first container 1-1. Stir evenly at room temperature. Add 0.5 parts of ammonium persulfate again and continue stirring for 10 min. Finally, add 1.0 part of catechol and continue stirring for 10 min to obtain material A 2-1.

[0045] (2) Preparation of material B2-2: 100 parts of deionized water were added to the second container 1-2, and 0.5 parts of sodium carboxymethyl cellulose or polysaccharide, 0.5 parts of ammonium persulfate and 0.5 parts of surfactant were added to the water and stirred to obtain material B2-2;

[0046] (3) After materials A2-1 and B2-2 are prepared, materials A2-1 and B2-2 are extracted by high-pressure dual-liquid transfer pump 3 respectively. Material A2-1 enters the first gas-liquid mixer 6-1 through the first one-way valve 4-1. The high-pressure nitrogen generated by the mobile nitrogen generator 5 is used as a power source to spray material A in the first gas-liquid mixer 6-1 through the first nozzle 7-1. At the same time, material B enters the second gas-liquid mixer 6-2 through the second one-way valve 4-2. The high-pressure nitrogen generated by the mobile nitrogen generator 5 is used as a power source to spray material B in the second gas-liquid mixer 6-2 through the second nozzle 7-2. During the transportation and mixing process, materials A and B react to form atomizable materials, that is, a vapor gel material that can be diffused with the airflow to seal leaks.

[0047] Subsequently, the atomizable material diffuses and deposits with the airflow, cross-linking into a film on the surface and pores of the residual coal, thereby forming a plugging layer on the surface of the residual coal in the goaf.

[0048] like Figure 5 The image shows the film-forming effect after the atomizable material is sprayed. The atomizable material is easily atomized and can be transported by airflow to fissures and goaf areas. It possesses strong adhesion, good flexibility, and film-forming properties, and is environmentally friendly. Utilizing the characteristic of airflow transport along the leakage channel, the prepared atomized gel material is transported into the leakage channel for deposition, cross-linking, and film formation to plug the leak. Using the construction method of this invention for leak plugging improves the accuracy of the sealing process.

[0049] Example 2

[0050] like Figure 1-3 As shown, a method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel includes the following steps:

[0051] In the first stage, during the mining of coal seam 10 using the 2GN00 method, a set of spray devices 7 is arranged every other support on the intake side, every two supports in the middle of the coal face, and every four supports near the return air side. Then, material A2-1 in container 1-1 is transported to the first gas-liquid mixer 6-1 via a high-pressure double-liquid pump 3 and a first one-way valve 4-1. High-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the first gas-liquid mixer 6-1 to the first nozzle 7-1 in the spray device 7. The first nozzle 7-1 then sprays the material into the uncollapsed goaf area. Spraying is carried out in the fall zone 8-1; simultaneously, material B2-2 in container 1-2 is transported to the second gas-liquid mixer 6-2 via the high-pressure dual-liquid transfer pump 3 and the second one-way valve 4-2. Then, the high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the second gas-liquid mixer 6-2 to the second nozzle 7-2 in the spray device 7. The second nozzle 7-2 is used to spray into the non-collapsed area 8-1 of the goaf. During the transport and mixing process, materials A and B react to form atomizable materials, which diffuse and deposit with the airflow, cross-linking into a film on the surface and pores of the residual coal, thereby forming a plugging layer on the surface of the residual coal in the goaf 8. At the same time, a flexible windbreak curtain 9 is installed on the return air side of the working face to prevent the material from entering the return airway with the airflow.

[0052] In the second stage, after the roof is cut to form a roadway and the overlying rock strata of the goaf 8 collapse, the atomizable material 2 in container 1 is transported to the gas-liquid mixer 6 through the high-pressure double-liquid transfer pump 3 and the one-way valve 4. Then, the high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the materials A and B in the gas-liquid mixer to the spraying device 7. The spraying device 7 sprays the atomizable material into the goaf collapse area 8-2 through the reserved spray holes 11. The materials A and B are deposited and cross-linked into a film again in the air leakage channel and the goaf to form a leak-blocking layer.

[0053] In the third stage, after the goaf 8 is completely stabilized, sulfur hexafluoride is used to determine the air leakage channel. On the windward side of the air leakage channel, atomizing materials A and B are sprayed using atomizing device 7. The atomizing materials A and B are then transported by airflow to the cracks in the compacted zone 8-3 of the goaf, and gradually deposited and cross-linked to form a film to form a leak-stopping layer.

[0054] The atomizable material used is an aerosol gel material with precise leak-sealing function, and its preparation method includes the following specific steps:

[0055] (1) Preparation of material A2-1: Weigh 8 parts of deionized water at room temperature and add it to the first container 1-1. Then weigh 8 parts of organic small molecule monomer (acrylic acid) and 0.2 parts of surfactant and add them to the first container 1-1. Stir evenly at room temperature. Add 0.8 parts of ammonium persulfate again and continue stirring for 20 min. Finally, add 0.8 parts of catechol and continue stirring for 10 min to obtain material A2-1.

[0056] (2) Preparation of material B2-2: 100 parts of deionized water were added to the second container 1-2, and 0.8 parts of sodium carboxymethyl cellulose or polysaccharide, 0.8 parts of ammonium persulfate and 0.8 parts of surfactant were added to the water and stirred to obtain material B2-2;

[0057] (3) After materials A2-1 and B2-2 are prepared, they are mixed to generate atomizable material.

[0058] Other parts not mentioned are the same as in Example 1.

[0059] Example 3

[0060] like Figure 1-3 As shown, a method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel includes the following steps:

[0061] In the first stage, during the mining of coal seam 10 using the 2GN00 method, a set of spray devices 7 is arranged every other support on the air intake side, every two supports in the middle of the coal face, and every four supports near the return air side. Then, the material A2-1 in container 1-1 is transported to the first gas-liquid mixer 6-1 via the high-pressure double-liquid pump 3 and the first one-way valve 4-1. The high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the first gas-liquid mixer 6-1 to the first nozzle 7-1 in the spray device 7. The first nozzle 7-1 is then used to spray the material into the uncollapsed goaf area. Spraying is carried out in the fall zone 8-1; simultaneously, material B2-2 in container 1-2 is transported to the second gas-liquid mixer 6-2 via the high-pressure dual-liquid transfer pump 3 and the second one-way valve 4-2. Then, the high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the material in the second gas-liquid mixer 6-2 to the second nozzle 7-2 in the spray device 7. The second nozzle 7-2 is used to spray into the non-collapsed area 8-1 of the goaf. During the transport and mixing process, materials A and B react to form atomizable materials, which diffuse and deposit with the airflow, cross-linking into a film on the surface and pores of the residual coal, thereby forming a plugging layer on the surface of the residual coal in the goaf 8. At the same time, a flexible windbreak curtain 9 is installed on the return air side of the working face to prevent the material from entering the return airway with the airflow.

[0062] In the second stage, after the roof is cut to form a roadway and the overlying rock strata of the goaf 8 collapse, the atomizable material 2 in container 1 is transported to the gas-liquid mixer 6 through the high-pressure double-liquid transfer pump 3 and the one-way valve 4. Then, the high-pressure gas generated by the mobile nitrogen generator 5 is used to transport the materials A and B in the gas-liquid mixer to the spraying device 7. The spraying device 7 sprays the atomizable material into the goaf collapse area 8-2 through the reserved spray holes 11. The materials A and B are deposited and cross-linked into a film again in the air leakage channel and the goaf to form a leak-blocking layer.

[0063] In the third stage, after the goaf 8 is completely stabilized, sulfur hexafluoride is used to determine the air leakage channel. On the windward side of the air leakage channel, atomizing materials A and B are sprayed using atomizing device 7. The atomizing materials A and B are then transported by airflow to the cracks in the compacted zone 8-3 of the goaf, and gradually deposited and cross-linked to form a film to form a leak-stopping layer.

[0064] The atomizable material used is an aerosol gel material with precise leak-sealing function, and its preparation method includes the following specific steps:

[0065] (1) Preparation of material A2-1: Weigh 10 parts of deionized water at room temperature and add it to the first container 1-1. Then weigh 9 parts of organic small molecule monomer (acrylic acid) and 0.5 parts of surfactant and add them to the first container 1-1. Stir evenly at room temperature. Add 1.0 part of ammonium persulfate again and continue stirring for 30 min. Finally, add 0.5 parts of catechol and continue stirring for 10 min to obtain material A.

[0066] (2) Preparation of material B2-2: 100 parts of deionized water were added to the second container 1-2, and 0.8 parts of sodium carboxymethyl cellulose or polysaccharide, 0.8 parts of ammonium persulfate and 0.8 parts of surfactant were added to the water and stirred to obtain material B;

[0067] (3) After materials A2-1 and B2-2 are prepared, they are mixed to generate atomizable material.

[0068] Other parts not mentioned are the same as in Example 1.

[0069] The OP-10 used in this invention is an emulsifier, OP-10, a surfactant.

[0070] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for preventing air leakage in goaf areas using aerosol gel based on the 2GN00 method, characterized in that, The method uses the air leakage in the goaf as a carrier to atomize the atomized material and transport it to the goaf. In the goaf, the material enters the pores of the coal with the airflow and cross-links into a gel, blocking the pores of the coal and reducing the contact between the active groups in the coal and oxygen. Then, the material is gradually deposited into a film in the goaf and its air leakage channels to block the air leakage channels. The atomizable material includes material A and material B; wherein, material A includes an organic small molecule monomer with cross-linking film-forming function, a substance containing phenolic hydroxyl groups, an initiator, a surfactant, and water, and material B includes a cross-linking agent, an initiator, a surfactant, and water; materials A and B are mixed and reacted to form an atomized gel material with precise leak-sealing function; The specific construction process includes the following steps: In the first stage, during the mining process using the 2GN00 method, a spraying device installed on the coal mining support is used to spray atomized materials A and B into the unsealed goaf area behind the support using different nozzles. The atomized materials diffuse and mix with the airflow. Materials A and B react during the transport and mixing process, cross-linking into a film in the pores and on the surface of the residual coal, forming a plugging layer to isolate oxygen on the surface of the residual coal in the goaf. In the second stage, after the roof is cut to form a roadway and the overlying rock strata of the goaf collapse, atomizable materials A and B are sprayed in the air intake roadway using the reserved spray holes. Atomizable materials A and B enter the goaf through the air leakage channel and are deposited and reacted again in the air leakage channel and goaf to cross-link into a film, forming a plugging layer. In the third stage, after the goaf is fully compacted and stabilized, sulfur hexafluoride is used to determine the air leakage channel. Atomizable materials A and B are sprayed at the windward side of the air leakage channel using pre-reserved spray holes, and the airflow is used to transport the atomizable materials into the cracks. Materials A and B gradually deposit and cross-link to form a film to form a leak-stopping layer.

2. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, In the first stage, the spraying devices are arranged as follows: a set of spraying devices is arranged every other support near the end of the air intake side, each set including two nozzles, namely the first nozzle and the second nozzle, which spray materials A and B respectively; a set of spraying devices is arranged every two supports in the middle of the coal mining face; and a set of spraying devices is arranged every four supports near the end of the return air side.

3. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, In the second stage, the spray holes are arranged as follows: after the top is cut to form the tunnel, a spray hole is reserved every 30 meters at the top of the tunnel.

4. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, The spraying device is a high-pressure spraying device, driven by high-pressure nitrogen gas, with a spray pressure of 7~12 MPa, an inclination angle of 52.5-60°, and a spray distance of 6-12 m.

5. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, In the first stage, a flexible windbreak curtain is installed at the upper corner of the return air side of the working face.

6. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 5, characterized in that, The flexible windbreak curtain is a duct cloth, which is divided into strips and suspended from the top of the ceiling anchor rod so as not to obstruct normal ventilation.

7. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, The preparation and application method of the aforementioned vapor gel material with precise leak-sealing function is as follows: (1) First, take 7-9 parts of organic small molecule monomer material and surfactant and add them to 5-10 parts of water. Then, add 0.5-1 parts of initiator to the above solution and stir at room temperature for 10-30 minutes. Finally, add 0.5-1.0 parts of substance containing phenolic hydroxyl groups and stir for 10 minutes to form material A. (2) Add 0.5-1 parts of crosslinking agent, 0.1-0.5 parts of initiator and 0.5-1 parts of surfactant to 100 parts of water and stir slowly for 10 minutes to obtain material B; (3) After atomizing materials A and B, they are sprayed out using different nozzles of a spraying device. A and B react during the transport and mixing process to obtain the vapor gel material. (4) When in use, material A is transported to the first gas-liquid mixer via the first one-way valve through the high-pressure dual-liquid transfer pump. Then, the high-pressure gas generated by the mobile nitrogen generator is used to transport material A in the first gas-liquid mixer to the first nozzle of the spray device and spray it out. At the same time, material B is transported to the second gas-liquid mixer via the second one-way valve through the high-pressure dual-liquid transfer pump. Then, the high-pressure gas generated by the mobile nitrogen generator is used to transport material B in the second gas-liquid mixer to the second nozzle of the spray device and spray it out. Material A and B react during the transport and mixing process, cross-linking into a film on the surface and pores of the residual coal to form a plugging layer.

8. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, In material A, the organic small molecule monomer with cross-linking film-forming function is one or more of acrylic acid, polyvinyl alcohol, sodium alginate and their compound materials; the substance containing phenolic hydroxyl groups is monophenolic, bisphenolic, and polyphenolic hydroxyl substances; the initiator is a peroxide, and is one or a mixture of two of ammonium persulfate and sodium persulfate; the surfactant is OP-10.

9. The method for preventing air leakage in the goaf of the 2GN00 method based on aerosol gel as described in claim 1, characterized in that, In material B, the crosslinking agent is sodium carboxymethyl cellulose or polysaccharide, the initiator is one or a mixture of two of ammonium persulfate and sodium persulfate, and the surfactant is one or a mixture of two of sodium dodecylbenzenesulfonate and OP-10.

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