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CN-116025405-B - Method for preventing and controlling air leakage of goaf of 2GN00 working method based on aerosol gel

CN116025405BCN 116025405 BCN116025405 BCN 116025405BCN-116025405-B

Abstract

The invention relates to the technical field of coal mine safety, in particular to a method for preventing and controlling air leakage in a goaf of a 2GN00 working method based on steam fog gel. According to the method, the characteristics that air flows move along an air leakage channel are utilized, air leakage is taken as a carrier, atomized materials A and B are conveyed into a goaf formed after coal mining by a 2GN00 working method by utilizing different pipelines and spray heads of a spraying device, after the two materials react in the goaf and the air leakage channel, pores of coal are blocked, the materials adhere to the surface of a coal rock mass, the surfaces are crosslinked into glue, a layer of covering film is formed, and contact between active groups in the coal and oxygen is reduced, so that the aim of accurately plugging the coal is achieved. The plugging method disclosed by the invention is not only convenient, but also improves the plugging accuracy.

Inventors

  • LU WEI
  • LI JINLIANG
  • YANG YANG
  • ZHANG QINGSONG
  • LV MAOYUN
  • LI JINHU
  • ZHUO HUI
  • WANG CHANGXIANG
  • ZHAO SHUJIE

Assignees

  • 安徽理工大学
  • 内蒙古黄陶勒盖煤炭有限责任公司

Dates

Publication Date
20260508
Application Date
20221228

Claims (9)

  1. 1. A method for preventing and controlling air leakage of a 2GN00 working method goaf based on aerosol gel is characterized in that the method takes air leakage of the goaf as a carrier, atomized materials are conveyed to the goaf, the atomized materials enter pores of coal along with wind flow in the goaf to crosslink into gel, the pores of the coal are blocked, contact between active groups in the coal and oxygen is reduced, and then the air leakage channel is gradually deposited into a film to block the air leakage channel; The nebulizable material comprises a material A and a material B, wherein the material A comprises an organic micromolecule monomer with a crosslinking film forming function, a substance containing phenolic hydroxyl groups, an initiator, a surfactant and water, and the material B comprises a crosslinking agent, an initiator, a surfactant and water; The concrete construction comprises the following steps: In the first stage, in the mining process of a working face by adopting a 2GN00 working method, an atomizing device arranged on a coal mining support is utilized, atomized materials A and B are respectively sprayed to a goaf which is not plugged behind the support by utilizing different spray heads of the atomizing device, the atomized materials are diffused and mixed along with wind flow, the materials A and B react in the migration and mixing process, cross-link is formed in pores of residual coal and on the surface of the residual coal of the goaf, and a plugging layer for isolating oxygen is formed on the surface of residual coal of the goaf; In the second stage, after a tunnel is formed by roof cutting and a goaf overlying strata collapses, spraying nebulizable materials A and B on an air inlet tunnel by utilizing reserved spray holes, enabling the nebulizable materials A and B to enter the goaf along with an air leakage channel, and depositing and crosslinking into a film again in the air leakage channel and the goaf to form a plugging layer; And thirdly, after the goaf is completely compacted and stabilized, determining an air leakage channel by using sulfur hexafluoride, spraying nebulizable materials A and B at the air side of the air leakage channel by using reserved spray holes, and transporting the nebulizable materials into cracks by using air current, wherein the materials A and B are gradually deposited and crosslinked to form a plugging layer.
  2. 2. A method for preventing and controlling air leakage in a 2GN00 working goaf based on an aerosol-gel method as claimed in claim 1, wherein in the first stage, spraying devices are arranged in a mode that a group of spraying devices is arranged on every other bracket near an air inlet side end, each group comprises two spraying heads, namely a first spraying head and a second spraying head, materials A and B are respectively sprayed, a group of spraying devices is arranged on every other bracket in the middle of a coal face, and a group of spraying devices is arranged on every other bracket near an air return side end.
  3. 3. The method for preventing and controlling air leakage of 2GN00 goaf based on the aerosol-gel method as claimed in claim 1, wherein in the second stage, the spray holes are arranged by reserving one spray hole at intervals of 30 m at the top of a roadway after roof cutting and roadway forming.
  4. 4. The method for preventing and controlling air leakage in a 2GN00 working method goaf based on the aerosol gel as claimed in claim 1, wherein the spraying device is a high-pressure spraying device, the driving force is high-pressure nitrogen, the spraying pressure is 7-12 mpa, the inclination angle is 52.5-60 degrees, and the spraying distance is 6-12m.
  5. 5. A method for controlling air leakage in a 2GN00 goaf based on a gas-fog gel as claimed in claim 1, wherein the first stage is to provide a flexible wind screen at the upper corner of the return air side of the working surface.
  6. 6. The method for preventing and controlling air leakage in a 2GN00 working method goaf based on the aerosol and gel method according to claim 5, wherein the flexible air blocking curtain is an air duct cloth which is divided into strips, and the top end of the air duct cloth is suspended on a roof anchor rod so as not to prevent normal ventilation.
  7. 7. The method for preventing and controlling air leakage in a 2GN00 working method goaf based on the aerosol gel according to claim 1, wherein the aerosol gel material with the accurate plugging function is prepared by the following specific steps: (1) Firstly, 7-9 parts of organic micromolecular monomer material and surfactant are added into 5-10 parts of water, then 0.5-1 part of initiator is added into the solution and stirred for 10-30min at room temperature, finally 0.5-1.0 part of substance containing phenolic hydroxyl is added and stirred for 10min, and finally material A is formed; (2) Adding 0.5-1 part of cross-linking agent, 0.1-0.5 part of initiator and 0.5-1 part of surfactant into 100 parts of water, and slowly stirring for 10min to obtain a material B; (3) Atomizing the material A and the material B, respectively spraying by using different spray heads of a spraying device, and reacting A, B in the process of transportation and mixing to obtain the aerosol gel material; (4) When the device is used, the material A is conveyed to the first gas-liquid mixer through the first one-way valve by the high-pressure double-liquid conveying pump, then the material A in the first gas-liquid mixer is conveyed to the first nozzle of the spraying device by utilizing high-pressure gas generated by the movable nitrogen making machine, and sprayed out by utilizing the first nozzle, meanwhile, the material B is conveyed to the second gas-liquid mixer through the second one-way valve by the high-pressure double-liquid conveying pump, then the material B in the second gas-liquid mixer is conveyed to the second nozzle of the spraying device by utilizing the high-pressure gas generated by the movable nitrogen making machine, and then the materials A and B react in the migration and mixing processes by utilizing the second nozzle, and are crosslinked into films on the surface and in pores of the coal to form the plugging layer.
  8. 8. The method for preventing and controlling air leakage in a 2GN00 working method goaf based on the aerosol gel as claimed in claim 1, wherein in the material A, the organic small molecular monomer with a crosslinking film forming function is one or a mixture of more of acrylic acid, polyvinyl alcohol, sodium alginate and a compound material thereof, the substance containing phenolic hydroxyl groups is a substance of mono-phenolic hydroxyl group, bisphenol hydroxyl group and polyphenol hydroxyl group, the initiator is peroxide and is one or a mixture of two of ammonium persulfate and sodium persulfate, and the surfactant is OP-10.
  9. 9. The method for preventing and controlling air leakage in a 2GN00 working method goaf based on the aerosol gel as claimed in claim 1, wherein in the material B, the cross-linking agent is sodium carboxymethyl cellulose or glycan, 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 dodecyl benzene sulfonate and OP-10.

Description

Method for preventing and controlling air leakage of goaf of 2GN00 working method based on aerosol gel Technical Field The invention relates to the technical field of coal mine safety materials, in particular to a method for preventing and controlling air leakage in a goaf of a 2GN00 working method based on steam-fog gel. Background The spontaneous combustion of coal seriously threatens the safety production of mines, and the filling of plugging air is a key technology for preventing and controlling the spontaneous combustion of coal. At present, the mine fracture plugging technology can be divided into a roadway fracture plugging technology and a goaf plugging technology according to different positions. The tunnel crack is mainly plugged by spraying plugging materials, and the materials used are mainly divided into inorganic and organic two types. The inorganic materials mainly comprise concrete, cement mortar, fly ash, gel and the like, and the inorganic filling plugging material has the characteristics of low price and wide sources. However, most inorganic materials have no toughness, are easy to break along with the pressure change of mines to form a certain air leakage channel, and are difficult to meet the requirement of durable air leakage. Compared with inorganic filling plugging materials, the organic polymer filling plugging materials have the characteristics of controllable curing time, expandability, good air tightness, capability of bearing certain rock stratum movement and the like, and embody good service performance. However, the existing polymer foam material reacts to release a large amount of heat in the filling process, and secondary disasters are easy to occur. Both types of materials are difficult to meet the requirement of 2GN00 for coal pillar-free forward mining leakage blocking, because a retaining roadway formed by roof cutting or filling is easily influenced by multiple mining to generate the conditions of difficult roof connection and unreasonable wall connection, in addition, the retaining roadway wall is often subjected to fracturing deformation, so that the materials attached to the wall fall off or crack, a new air leakage channel is generated, and the problem of air leakage can be solved by repeated spraying, so that thorough leakage blocking from the periphery of a goaf is more and more difficult. On the contrary, if the problem of goaf air leakage is solved, the goaf air leakage quantity is not increased even if the roadway is cracked and air leakage occurs, so that the goaf spontaneous combustion probability is reduced. Therefore, the prevention or reduction of goaf air leakage is the root of solving the hidden danger of 2GN00 coal pillar-free advancing fire. The technology for preventing and controlling the leakage of the goaf mainly comprises grouting (gel), foam injection, stopping agent spraying and the like. The grouting technology has low cost, but is easy to generate a 'ditching' phenomenon, cannot cover a goaf in a large range and is difficult to accumulate to a high place. The foam material is considered to be the most suitable technology for preventing and curing spontaneous combustion of goaf coal due to the characteristics of wide diffusion range, good accumulation, capability of covering high-altitude residual coal and the like, but the traditional water-based foam, three-phase foam and other fire prevention and extinguishing materials are easy to crack and have poor long-term covering and oxygen-isolation effects, and in addition, the construction method of the prevention and curing technology is difficult to accurately leak stoppage by utilizing wind current. Therefore, the technology cannot meet the requirements of accurately plugging and preventing coal spontaneous combustion under the non-coal-pillar advancing mining condition. Disclosure of Invention The invention aims to solve the technical problem of providing a method for preventing and controlling air leakage in a goaf of a 2GN00 working method based on steam-gel, which is used for solving at least one problem in the background technology. The technical scheme adopted is as follows: The method for preventing and controlling air leakage of the goaf based on the 2GN00 working method based on the aerosol gel comprises the steps of taking air leakage of the goaf as a carrier, atomizing an atomized material, conveying the atomized material to the goaf, adhering the atomized material to the surfaces of coal and rock mass in the goaf and an air leakage channel, and crosslinking the atomized material to form a layer of covering film on the surfaces to achieve the aim of accurately stopping leakage; The method specifically comprises the following steps: In the first stage, in the mining process of a working face by adopting a 2GN00 working method, an atomizing device arranged on a coal mining support is utilized to respectively spray an atomized material A and an atomized material B in a goaf which is not