Ventilation method for preventing corner gas over-limit on stope face

Abstract

The invention relates to the technical field of coal mining, in particular to a ventilation method for preventing corner gas over-limit on a stope face, which comprises the following steps of: adopting a U-shaped ventilation mode for each stope face, a left side mining area branch roadway, a right side mining area branch roadway and an upper side mining area branch roadway which are connected to form a through ventilation roadway are constructed along the boundary line of the mining area roadway, the left side mining area branch roadway is communicated with the mining area air return roadway, and the right side mining area branch roadway is communicated with the mining area air inlet roadway; a plurality of rows of penetrating holes are constructed in a protection coal pillar, communication of a return airway and a transportation crossheading roadway of a preparation working face is achieved, after an open-off cut roadway of a stope working face is pushed through the penetrating holes, the penetrating holes in the deep portion of a goaf of the stope working face are sealed, the penetrating holes entering the goaf are opened, and therefore on the basis that ventilation stability of the whole mining area is guaranteed, the goaf is protected. The gas accumulation at the upper corner is avoided, the potential safety hazard of ventilation of the goaf is solved, and the operation safety during the coal production period is effectively guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of coal mining, and in particular to a ventilation method for preventing gas from exceeding the limit in the upper corner of a mining surface. Background Art

[0002] The new version of the "Coal Mine Safety Regulations" has strict regulations on ventilation management of mining faces, including strictly prohibiting ventilation in goaf areas and strictly prohibiting the establishment of gas emission tunnels. In order to strengthen ventilation management of mining faces, many provinces have abolished the multi-tunnel ventilation method and adopted the "two-in-one" or "U" type ventilation method, which has improved the reliability of the mining face ventilation system.

[0003] However, the change in ventilation mode has increased the difficulty of controlling gas in the upper corner. In order to prevent a large amount of gas from flowing to the upper corner during the production process of the mining face, most mines use high-position drilling holes in the roof, medium- and low-position drilling holes, buried pipes in the goaf, or inserted pipes in the upper corner to intercept the gas flowing from the goaf to the upper corner, change the gas flow channel, and avoid gas accumulation in the upper corner. However, this method has defects such as complicated procedures and great management difficulty. Although some gas in the goaf can be intercepted to a certain extent, the safety hazards of excessive gas in the upper corner and gas concentration approaching the critical value of excessive limit still cannot be resolved. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a ventilation method that can extract gas from the entire working face of the mining area and avoid gas accumulation in the upper corners to prevent excessive gas in the upper corners of the mining face.

[0005] The present invention provides a ventilation method for preventing gas from exceeding the limit in the upper corner of a mining surface, comprising the following steps:

[0006] S1. Each mining working face adopts a U-shaped ventilation method, and a mining area branch roadway is constructed along the boundary line of the mining area roadway. The mining area branch roadway includes a left mining area branch roadway, a right mining area branch roadway and an upper mining area branch roadway connected to form a through ventilation roadway. The left mining area branch roadway is connected to the mining area return air roadway of the mining area roadway, and the right mining area branch roadway is connected to the mining area intake air roadway of the mining area roadway;

[0007] S2. Construct multiple rows of penetration holes in the protective coal pillar on the side of the return air lane of the mining face close to the adjacent preparation working face, so as to connect the return air lane with the transport drift lane of the preparation working face. After the cutting lane of the mining face passes through the penetration holes, the penetration holes deep in the goaf of the mining face are closed, and the penetration holes entering the goaf are opened, so as to realize the circulation of the penetration holes into the goaf in turn for return air.

[0008] Optionally, one end of the air inlet tunnel of the mining working face is connected to the air inlet tunnel of the mining area, and the other end is connected to the cut-eye tunnel;

[0009] One end of the return air tunnel is connected to the return air tunnel of the mining area, and the other end is connected to the cutting eye tunnel.

[0010] Optionally, the step S2 of constructing multiple rows of penetration holes specifically includes the following steps:

[0011] Before the mining face starts mining, a penetration hole close to the eye-cutting roadway is constructed, and a leading distance of 10 to 15 meters is maintained from the eye-cutting roadway. Both ends of the penetration hole that has not been passed by the eye-cutting roadway are sealed, and the sealing cover plates at both ends of the penetration holes 1 to 2 meters close to the eye-cutting roadway and passing through the eye-cutting roadway are removed to realize ventilation on both sides of the protective coal pillar;

[0012] A drainage pipe is connected to the penetration hole pushed through the cut-eye lane and entering the goaf 2 to 10 m away, the drainage pipe is connected to one end of the penetration hole close to the transport drift lane, and is connected to the drainage main pipe laid on one side of the adjacent preparation working face, and the drainage main pipe is connected to the ground drainage pump;

[0013] A cover plate is provided to seal the penetration hole that is pushed through the cut-eye tunnel and enters the goaf for more than 10m. The cover plate is provided at one end of the penetration hole close to the transport drift tunnel.

[0014] Optionally, the penetration hole is drilled with a drill bit having a diameter of 500 to 800 mm, and after the hole is formed, the penetration hole is protected with a steel pipe;

[0015] The penetration holes are constructed sequentially from top to bottom, with 2 to 5 penetration holes arranged in each row, the spacing between penetration holes in the same row being 0.2 to 2.5 m, and the spacing between penetration holes in each row being 0.5 to 1 m.

[0016] Optionally, one end of the transport chute roadway is connected to the air intake roadway of the mining area, and the other end is connected to the branch roadway of the upper mining area;

[0017] The return air chute tunnel of the preparation working face is connected to the return air tunnel of the mining area, and the preparation working face adopts full wind pressure ventilation.

[0018] Optionally, the mining area branch tunnel is arranged at the periphery of the mining working face, and the distance from the boundary tunnel of the mining working face is 15 to 20m.

[0019] Compared with the prior art, the technical solution provided by the embodiment of the present invention has the following beneficial effects:

[0020] The ventilation method for preventing excessive gas in the upper corners of the mining face provided by the embodiment of the present invention ensures the stability of ventilation of the working face in the entire mining area by performing U-shaped ventilation on the working face in the mining area, avoids excessive gas concentration in the return air lane, and alleviates the pressure of excessive gas in the return air flow. A plurality of rows of large-diameter penetration holes are constructed in the protective coal pillar on the side of the return air lane of the mining working face close to the adjacent preparation working face. After the cutting eye lane of the mining working face pushes through the penetration holes, the penetration holes deep in the goaf are closed and the penetration holes entering the goaf are opened, thereby achieving the purpose of the penetration holes circulating and entering the goaf in turn for return air. Therefore, on the basis of ensuring stable ventilation of the entire mining area, no upper corner gas accumulation is achieved, the safety hazard of ventilation in the goaf is solved, and the operation safety during coal production is effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0023] Figure 1 A schematic diagram of a working surface and a penetration hole in a mining area according to an embodiment of the present invention;

[0024] Figure 2 A cross-sectional view of a through hole for constructing a return air lane according to an embodiment of the present invention;

[0025] Figure 3 It is a cross-sectional view of the through-hole extraction inside the goaf according to an embodiment of the present invention.

[0026] Among them, 1. mining working face; 2. preparation working face; 3. return air lane in mining area; 4. air intake lane in mining area; 5. ground extraction pump; 6. branch lane in left mining area; 7. branch lane in right mining area; 8. branch lane in upper mining area; 9. cutting lane; 10. goaf; 11. air intake lane; 12. return air lane; 13. protective coal pillar; 14. transport chute lane; 15. return air chute lane; 16. chute extraction pipe; 17. first penetration hole; 18. second penetration hole; 19. third penetration hole; 20. fourth penetration hole; 21. branch extraction pipe; 22. extraction pipe; 23. extraction main pipe. DETAILED DESCRIPTION

[0027] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0029] Reference Figure 1 As shown, an embodiment of the present invention provides a ventilation method for preventing gas from exceeding the limit in the upper corner of a mining surface, comprising the following steps:

[0030] S1. Each mining face 1 adopts a U-shaped ventilation method, and a mining area branch tunnel is constructed along the boundary line of the mining area tunnel. The mining area branch tunnel includes a left mining area branch tunnel 6, a right mining area branch tunnel 7 and an upper mining area branch tunnel 8 which are connected to form a through ventilation tunnel. The left mining area branch tunnel 6 is connected to the mining area return air tunnel 3 of the mining area tunnel, and the right mining area branch tunnel 7 is connected to the mining area intake air tunnel 4 of the mining area tunnel;

[0031] S2. Construct multiple rows of penetration holes in the protective coal pillar 13 on the side of the return air lane 12 of the mining face 1 close to the adjacent preparation face 2 to achieve the connection between the return air lane 12 and the transport drift lane 14 of the preparation face 2. After the cutting lane 9 of the mining face 1 pushes through the penetration holes, the penetration holes deep in the goaf 10 of the mining face 1 are closed, and the penetration holes entering the goaf 10 are opened, so that the penetration holes circulate and enter the goaf 10 in turn for return air.

[0032] Among them, the mining area branch tunnel can provide return air for the planned working face in the entire mining area. During the production of the mining working face 1, a part of the return air flows through the return air tunnel 12 and then enters the mining area return air tunnel 3, and the other part of the return air flows out from the two end outlets of the tunnel adjacent to the return air tunnel 12 through the penetration holes. One end of the tunnel adjacent to the return air tunnel 12 is connected to the mining area return air tunnel 3, and the airflow of the mining area return air tunnel 3 flows to the main return air tunnel of the mine, and the other end of the tunnel adjacent to the return air tunnel 12 is connected to the upper mining area branch tunnel 8, the upper mining area branch tunnel 8 is connected to the left mining area branch tunnel 6, and the left mining area branch tunnel 6 is connected to the mining area return air tunnel 3, and the airflow flowing to the upper mining area branch tunnel 8 flows out through the left mining area branch tunnel 6, and then flows into the mining area return air tunnel 3. In other words, the return air of the mining working face is Part of the return air flows out from the transport chute tunnel 14 adjacent to the working face, and the other part of the return air flows out from the branch tunnel of the mining area that runs through the entire mining area. By adopting the U-shaped ventilation method, the stability of the ventilation of the entire mining area working face is guaranteed, the gas concentration in the return air tunnel 12 is avoided to exceed the limit, and the pressure of the return air flow gas exceeding the limit is relieved. Multiple rows of penetration holes are constructed in the protective coal pillar 13. After the cutting eye tunnel 9 of the mining working face 1 pushes through the penetration holes, the penetration holes deep in the goaf 10 are closed, and the penetration holes entering the goaf 10 are opened, so as to achieve the purpose of the penetration holes circulating and entering the goaf 10 for return air in turn. Therefore, on the basis of ensuring the stability of the ventilation of the entire mining area, it is achieved that there is no gas accumulation in the upper corner, the safety hazard of ventilation in the goaf is solved, and the operation safety during coal production is effectively guaranteed.

[0033] In order to ensure the reliability of ventilation in the mining area, the branch tunnels in the mining area are set at the periphery of the mining face 1, and the distance from the boundary tunnels of the mining face 1 is 15 to 20 meters.

[0034] Furthermore, the mining working face 1 adopts a U-shaped ventilation method, specifically, one end of the air inlet lane 11 of the mining working face 1 is connected to the mining area air inlet lane 4, and the other end is connected to the eye-cutting lane 9, and one end of the return air lane 12 is connected to the mining area return air lane 3, and the other end is connected to the eye-cutting lane 9.

[0035] Reference Figure 2 and Figure 3 As shown, the specific steps of constructing multiple rows of penetration holes in step S2 include:

[0036] Before mining begins at the mining face 1, a penetration hole close to the eye-cutting tunnel 9 is constructed and maintained at an advance distance of 10 to 15 m from the eye-cutting tunnel 9. Both ends of the penetration hole that has not been passed by the eye-cutting tunnel 9 are sealed. This penetration hole is the fourth penetration hole 20. A special sealing cover plate is used to temporarily seal the openings at both ends of the fourth penetration hole 20 that has not passed through the eye-cutting tunnel. The sealing covers at both ends of the penetration holes that are 1 to 2 m close to the eye-cutting tunnel 9 and pass through the eye-cutting tunnel 9 are removed. The penetration hole that passes through the eye-cutting tunnel 9 is the third penetration hole 19. When the eye-cutting tunnel 9 approaches the fourth penetration hole 20, the sealing covers at both ends of the fourth penetration hole 20 close to the eye-cutting tunnel 9 are removed. After the sealing covers are removed, the fourth penetration hole 20 becomes the third penetration hole 19 that can be ventilated normally, thereby realizing ventilation on both sides of the protective coal pillar 13.

[0037] A drainage pipe 22 is connected to a penetration hole with a distance of 2 to 10 m through which the cut-eye lane 9 is pushed and enters the goaf 10. The drainage pipe 22 is connected to one end of the penetration hole close to the transport chute lane 14 and is connected to a drainage main pipe 23 laid on one side of the adjacent preparation working face 2. The drainage main pipe 23 is connected to the ground drainage pump 5. This penetration hole is the second penetration hole 18. The second penetration hole 18 is connected to one end of the drainage main pipe 23 using a dedicated drainage pipe 22, so that the goaf 10 is realized. Extraction is carried out through buried pipes, and the control method is simple and reliable. The other end of the extraction main pipe 23 is connected to the ground extraction pump 5, realizing large flow and high negative pressure extraction. A chute extraction pipe 16 and a branch extraction pipe 21 are also arranged between the extraction main pipe 23 and the extraction and discharge pipe 22. The negative pressure generated by the ground extraction pump 5 is transmitted to the second penetration hole 18 through the extraction main pipe 23, the chute extraction pipe 16, the branch extraction pipe 21 and the extraction and discharge pipe 22, realizing the extraction of the penetration holes inside the goaf 10. Of course, the connection between the chute extraction pipe 16, the branch extraction pipe 21 and the extraction and discharge pipe 22 is provided with a three-way valve to facilitate the connection and disassembly of the chute extraction pipe 16, the branch extraction pipe 21 and the extraction and discharge pipe 22.

[0038] A cover plate is set to seal the penetration hole that is pushed through the cutting tunnel 9 and enters the goaf 10 for more than 10m. The cover plate is set at one end of the penetration hole close to the transport chute tunnel 14. This penetration hole is the first penetration hole 17. By re-covering and permanently sealing the first penetration hole 17 at one end of the transport chute tunnel 14, the goaf 10 is isolated from the adjacent preparation working face 2, avoiding high-concentration gas in the goaf 10 to directly flow into the transport chute tunnel 14 of the preparation working face 2, fundamentally solving the problem of excessive return air gas concentration. The cover plate for sealing the first penetration hole 17 is made of steel, and the first penetration hole 17 entering the goaf 10 is sealed with a steel cover plate, ensuring that the drilled hole is leak-proof and avoiding gas leakage in the goaf 10.

[0039] Of course, the number of the above-mentioned first penetration hole 17, second penetration hole 18, third penetration hole 19 and fourth penetration hole 20 changes dynamically with the advancement of the eye-cutting tunnel 9. When the eye-cutting tunnel 9 is close to the fourth penetration hole 20 to be constructed, the fourth penetration hole 20 becomes the third penetration hole 19 that can be ventilated normally. When the eye-cutting tunnel 9 is pushed a certain distance and the third penetration hole 19 enters the goaf 10 at a distance of 2 to 10m, it becomes the second penetration hole 18 that can be connected to the pumping pipe 22. When the second penetration hole 18 enters the goaf 10 at a distance of more than 10m, it becomes the permanently sealed first penetration hole 17.

[0040] Furthermore, the penetration holes are drilled with a drill bit having a diameter of 500 to 800 mm, and after the holes are formed, the penetration holes are protected with steel pipes; the penetration holes are constructed from top to bottom, with 2 to 5 penetration holes in each row, the spacing between penetration holes in the same row is 0.2 to 2.5 m, and the spacing between penetration holes in each row is 0.5 to 1 m.

[0041] In order to achieve stable ventilation in the entire mining area, one end of the transport chute tunnel 14 is connected to the mining area air inlet tunnel 4, and the other end is connected to the upper mining area branch tunnel 8; the return air chute tunnel 15 of the preparation working face 2 is connected to the mining area return air tunnel 3, and the preparation working face 2 adopts full wind pressure ventilation, that is, the preparation working face 2 adopts U-shaped ventilation. The tunnel airflow flows from the mining area air inlet tunnel 4 through the transport chute tunnel 14, flows out from the upper mining area branch tunnel 8, and finally reaches the mining area return air tunnel 3.

[0042] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0043] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments described herein, but should conform to the widest scope consistent with the principles and novel features invented herein.

Claims

1. A ventilation method for preventing gas from exceeding the limit in the upper corner of a mining surface, characterized in that: The following steps are involved: S1. Each mining working face (1) adopts a U-shaped ventilation method, and a mining area branch tunnel is constructed along the boundary line of the mining area tunnel. The mining area branch tunnel includes a left mining area branch tunnel (6), a right mining area branch tunnel (7) and an upper mining area branch tunnel (8) which are connected to form a through ventilation tunnel. The left mining area branch tunnel (6) is connected to the mining area return air tunnel (3) of the mining area tunnel, and the right mining area branch tunnel (7) is connected to the mining area intake air tunnel (4) of the mining area tunnel; S2. A plurality of rows of penetration holes are constructed in the protective coal pillar (13) on the side of the return air lane (12) of the mining face (1) close to the adjacent preparation face (2), so as to realize the connection between the return air lane (12) and the transport drift lane (14) of the preparation face (2). After the cut-eye lane (9) of the mining face (1) passes through the penetration holes, the penetration holes deep in the goaf (10) of the mining face (1) are closed, and the penetration holes entering the goaf (10) are opened, so as to realize the circulation of the penetration holes and sequentially entering the goaf (10) for return air.

2. The ventilation method for preventing excessive gas in the upper corner of the mining surface according to claim 1 is characterized in that: One end of the air intake tunnel (11) of the mining working face (1) is connected to the mining area air intake tunnel (4), and the other end is connected to the cut-eye tunnel (9); One end of the return air tunnel (12) is connected to the mining area return air tunnel (3), and the other end is connected to the eye-cutting tunnel (9).

3. The ventilation method for preventing excessive gas in the upper corner of the mining surface according to claim 1 is characterized in that: The step S2 of constructing multiple rows of penetration holes specifically includes the following steps: Before the mining face (1) starts mining, a penetration hole close to the eye-cutting tunnel (9) is constructed, and a leading distance of 10 to 15 meters from the eye-cutting tunnel (9) is maintained, and both ends of the penetration hole that has not been passed by the eye-cutting tunnel (9) are sealed, and the sealing cover plates at both ends of the penetration holes 1 to 2 meters close to the eye-cutting tunnel (9) and passing through the eye-cutting tunnel (9) are removed, so as to realize ventilation on both sides of the protective coal pillar (13); A drainage pipe (22) is connected to a penetration hole that is pushed through the cut-eye lane (9) and enters the goaf (10) 2 to 10 m away, the drainage pipe (22) is connected to one end of the penetration hole close to the transport drift (14), and is communicated with a drainage main pipe (23) laid on one side of an adjacent preparation working surface (2), and the drainage main pipe (23) is connected to a surface drainage pump (5); A cover plate is provided to seal the penetration hole that the cut-eye tunnel (9) pushes through and enters the goaf (10) for more than 10 m, and the cover plate is provided at one end of the penetration hole close to the transport drift (14).

4. The ventilation method for preventing excessive gas in the upper corner of the mining surface according to claim 3 is characterized in that: The penetration hole is drilled with a drill bit having a diameter of 500 to 800 mm, and after the hole is formed, the penetration hole is protected with a steel pipe; The penetration holes are constructed sequentially from top to bottom, with 2 to 5 penetration holes arranged in each row, the spacing between penetration holes in the same row being 0.2 to 2.5 m, and the spacing between penetration holes in each row being 0.5 to 1 m.

5. The ventilation method for preventing excessive gas in the upper corner of the mining surface according to claim 1 is characterized in that: One end of the transport chute tunnel (14) is connected to the mining area air intake tunnel (4), and the other end is connected to the upper mining area branch tunnel (8); The return air chute tunnel (15) of the preparation working face (2) is connected to the return air tunnel (3) of the mining area, and the preparation working face (2) adopts full wind pressure ventilation.

6. The ventilation method for preventing excessive gas in the upper corner of the mining surface according to claim 1 is characterized in that: The mining area branch tunnel is arranged at the periphery of the mining working face (1), and the distance from the boundary tunnel of the mining working face (1) is 15 to 20 meters.

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