A large-area gas prevention and control method for layer-by-layer progressive mining of close strong outburst coal seam group

Abstract

The present application provides a kind of near distance strong coal seam group layer by layer progressive mining large area gas prevention and control method, roadway layout and driving are carried out using roof and floor roadway combined arrangement mode, and in the process of driving roof or floor roadway, directional long borehole is used in roof roadway to carry out the regional gas advanced control of first mining layer driving face and stoping face area; after first mining layer stoping, lower adjacent layer is layer by layer progressive, and pressure relief mining of protected layer is carried out, at the same time, gas comprehensive control is carried out layer by layer in air inlet roadway of working face and air return roadway of working face, until the last coal seam of coal seam group; before the last coal seam of coal seam group is mined, pressure relief mining of protected layer is carried out, at the same time, regional gas supplementary control of driving face and stoping face area of the last coal seam of coal seam group is carried out through floor roadway. The present application combines roof or floor rock roadway and mining area raise, so that the roadway has the dual functions of detecting coal seam group occurrence and gas control, and layer by layer progressive pressure relief protection mining is realized, to achieve three-dimensional comprehensive control.

Description

Technical Field

[0001] This invention belongs to the field of coal mining technology and relates to a method for large-area gas control through progressive mining of closely spaced, high-burst coal seams. Background Technology

[0002] Coal seam group mining refers to mining multiple adjacent coal seams within a coalfield, rather than mining only a single seam. This method is common in some coal mining areas where multiple layers of coal seams form a coal seam group. The main methods of coal seam group mining include:

[0003] Layered mining: Selecting suitable coal seams for mining within a coal seam group requires significant differences in coal quality, thickness, dip angle, and other characteristics among the various coal seams, so as to select different layers of coal for mining and thus make full use of coal resources.

[0004] Joint mining: Simultaneously mining multiple adjacent coal seams, utilizing the voids between different seams to improve mining efficiency. This method requires suitable geological conditions between the coal seams to ensure minimal mutual influence.

[0005] Alternating mining: Mining different coal seams in rotation to balance coal resource extraction and mine safety and stability. This avoids over-mining of a particular coal seam within the same time period, which could lead to mine instability.

[0006] Layer-by-layer mining: Mining proceeds layer by layer from top to bottom, ensuring that the mining of one layer does not negatively impact the stability of the next. This method is particularly suitable for multi-layered, inclined coal seam groups. The strategy for layer-by-layer mining includes: Sectional mining: Dividing the coal seam group into different mining sections and mining them one section at a time. Ensuring the effective operation of the gas control system in each mining section. Staged ventilation: Employing a staged ventilation system for each mining section, allowing ventilation to be adjusted according to the progressive mining progress of the coal seam, ensuring concentrated gas extraction.

[0007] In the progressive mining of closely spaced, high-risk coal seams, gas control is a crucial aspect of ensuring mine safety and stability. Existing roadway layout and ventilation design methods include: multi-level roadway layout: based on the thickness and dip angle of the coal seam, multiple levels of main, auxiliary, and exploration roadways are designed. This ensures that the roadways cover the entire coal seam, forming a progressive roadway structure. Simultaneously, horizontal, oblique, and vertical intersecting roadways are employed to ensure rapid gas extraction. Connecting roadways are rationally designed to improve gas diffusion speed.

[0008] The choice of mining method for coal seam groups depends on various factors, including the geological characteristics, economic conditions, and safety requirements of the coal seam group. In most mines in Southwest my country, the coal seams are closely spaced and are characterized by strong outbursts. Some mines employ a progressive mining method, using single floor or roof rock roadways to extract gas from the coal seam group to prevent outbursts. However, due to uneven extraction across the coal seams, insufficient gas extraction from the first seam leads to a mismatch between mining and extraction operations. Inadequate gas control also poses safety hazards for subsequent coal seam mining operations. Therefore, it is necessary to address the shortcomings of the existing progressive mining method for closely spaced, strong outburst-prone coal seams and propose new large-area gas control methods to ensure the safety of mine operations. Summary of the Invention

[0009] In view of this, the purpose of this invention is to solve the above problems and provide a method for large-area gas control by progressively mining closely spaced, high-burst coal seams.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A method for large-area gas control in the progressive mining of closely spaced, high-outburst coal seams involves a combined roof and floor roadway layout and excavation. During the excavation of the roof or floor roadways, directional long boreholes are used in the roof roadways to pre-control regional gas in the first mining face and the longwall face. After the first mining face is mined, the adjacent lower layers are progressively excavated to depressurize the protected layer. At the same time, comprehensive gas control is carried out in the intake and return airways of the working face for the adjacent lower layers until the last coal seam in the coal seam group.

[0012] Before mining the last coal seam of the coal seam group, while the protected layer is depressurized during mining, regional gas replenishment and control are carried out through the bottom roadway for the tunneling and mining faces of the last coal seam of the coal seam group.

[0013] Furthermore, the combined arrangement of the top and bottom roadways is as follows:

[0014] In the roof strata of the first mining layer, interconnected roof haulage main roadway, roof track main roadway, roof return air main roadway, roof haulage uphill roadway, roof track uphill roadway and roof return air uphill roadway are arranged in a concentrated manner.

[0015] The longwall face adopts a double-wing layout. The top extraction roadway is arranged along the roof of the longwall face of the first mining layer. After the section inclined stone gate is made at the opening of the roof track uphill and the roof return air uphill, the longwall face intake roadway and the longwall face return airway are arranged along the longwall face of the first mining layer.

[0016] In the bottom strata of the last coal seam of the coal seam group, interconnected bottom haulage roadways, bottom track roadways, or bottom haulage uphill roadways, bottom track uphill roadways, bottom return air uphill roadways, and bottom return air roadways are arranged in a concentrated manner.

[0017] The roof slab transport roadway and the floor slab transport roadway are connected by an air intake stone gate, and the roof slab return air roadway and the floor slab return air roadway are connected by a return air stone gate.

[0018] A main shaft and an auxiliary shaft are used to connect the roof slab transport roadway and the roof slab track roadway, respectively, to form an intake air system; a return air shaft is used to connect the roof slab return air roadway, to form a return air system.

[0019] Furthermore, in the roof haulage main roadway, roof track main roadway, roof haulage uphill roadway, or roof track uphill roadway, directional long boreholes are used to carry out advanced regional gas control for the first mining layer's tunneling and mining faces. At the same time, in the top extraction roadway, through-layer downward boreholes are used to supplement gas control for the first mining layer's tunneling faces.

[0020] Furthermore, before the mining of the last coal seam of the coal seam group, regional gas supplementation and control are carried out in the bottom haulage roadway, bottom track roadway, bottom haulage uphill roadway, or bottom track uphill roadway for the tunneling and mining faces of the last coal seam of the coal seam group.

[0021] Furthermore, during the excavation of the roof or floor roadway, exploration is conducted simultaneously to obtain information on the structure and undulation of the coal seam, providing data support for coal roadway excavation.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. In this invention, the main roadway of the roof or floor rock and the uphill of the mining area are arranged in a combined manner, so that the roadway has the dual functions of detecting the occurrence of coal seam groups and preventing gas.

[0024] 2. This invention utilizes roof roadways, uphill tunnels, and rock tunnels for advanced gas control in the first mining face of a closely located, high-risk coal seam group. It then progressively depressurizes and mines the coal seam group layer by layer, simultaneously depressurizing and draining gas from adjacent lower layers. Finally, it supplements gas control in the last coal seam of the coal seam group through floor roadways, uphill tunnels, and rock tunnels. The roof roadways enable rapid and effective gas control in the first mining face, ensuring a fast mine succession rate. Progressive depressurization and protection mining are implemented layer by layer, and the roadways provide comprehensive control of gas from multiple adjacent lower layers, achieving a three-dimensional, comprehensive gas control system for closely located, high-risk coal seam groups through progressive depressurization and drainage.

[0025] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0027] Figure 1 This is a box plot of the large-area gas control method for the progressive mining of closely spaced, high-burst coal seams in this invention.

[0028] Figure 2 This is a correlation fitting analysis diagram between element measurement values ​​and burial depth data in this invention.

[0029] Attached diagram labels: 1-Roof haulage main roadway; 2-Roof track main roadway; 3-Floor haulage main roadway; 4-Floor track main roadway; 5-Main vertical shaft; 6-Auxiliary vertical shaft; 7-Roof haulage uphill; 8-Roof track uphill; 9-Roof return air uphill; 10-Floor haulage uphill; 11-Floor track uphill; 12-Floor return air uphill; 13-Return air shaft; 14-Return air portal; 15-Floor return air main roadway; 16-Roof return air main roadway; 17-Roof extraction roadway; 18-Working face return air roadway; 19-Working face intake air roadway; 20-Roof extraction roadway; 21-Intake air portal. Detailed Implementation

[0030] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0031] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0032] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0033] Please see Figures 1-2 A method for large-area gas control through progressive mining of closely spaced, high-risk coal seam groups, employing a combined roof and floor roadway layout for roadway arrangement and excavation. The combined roof and floor roadway layout is as follows:

[0034] In the roof strata of the first mining layer, interconnected roof haulage main roadway 1, roof track main roadway 2, roof return air main roadway 16, roof haulage uphill roadway 7, roof track uphill roadway 8 and roof return air uphill roadway 9 are arranged in a concentrated manner.

[0035] The longwall face adopts a double-wing layout. Top extraction roadways 17 and 20 are arranged along the roof of the longwall face of the first mining layer. After the section inclined rock gate is opened at the roof track uphill 8 and the roof return air uphill 9 to expose the coal, the working face intake roadway 19 and the working face return airway 18 are arranged along the longwall face of the first mining layer.

[0036] In the bottom strata of the last coal seam of the coal seam group, the interconnected bottom haulage roadway 3, bottom track roadway 4, bottom haulage uphill roadway 10, bottom track uphill roadway 11, bottom return air uphill roadway 12, and bottom return air roadway 15 are arranged in a concentrated manner.

[0037] The top slab transport roadway 1 and the bottom slab transport roadway 3 are connected by an air intake gate 21, and the top slab return air roadway 16 and the bottom slab return air roadway 15 are connected by a return air gate 14.

[0038] The main shaft 5 and the auxiliary shaft 6 are used to connect the roof slab transport roadway 1 and the roof slab track roadway 2 respectively to form an air intake system; the return air shaft 13 is used to connect the roof slab return air roadway 16 to form a return air system.

[0039] During the excavation of the roof or floor roadways, directional long boreholes are used in the roof haulage main roadway 1, roof track main roadway 2, roof haulage uphill roadway 7, or roof track uphill roadway 8 to conduct regional gas advance control of the first mining face and the mining face. At the same time, through-layer downward boreholes are used in the top drainage roadway to supplement the gas control of the first mining face. After the first mining face is mined, the lower adjacent layers are progressively advanced for depressurization mining of the protected layer. At the same time, gas comprehensive control is carried out layer by layer in the working face intake airway 19 and working face return airway 18 until the last coal seam in the coal seam group.

[0040] Before mining the last coal seam of the coal seam group, while carrying out depressurization mining of the protected layer, regional gas supplementation and treatment are carried out in the bottom haulage main roadway 3, bottom track main roadway 4, bottom haulage uphill roadway 10, or bottom track uphill roadway 11 for the tunneling and mining faces of the last coal seam of the coal seam group.

[0041] During the excavation of roof or floor roadways, exploration is conducted simultaneously to obtain information on the structure and undulation of the coal seam, providing data support for coal roadway excavation.

[0042] In this embodiment, coal seam 1 is the first mining seam of the coal seam group. Gas advance control is carried out in the working face intake airway 19 and working face return airway 18 area of ​​coal seam 1 through roof haulage roadway 1, roof track roadway 2, roof return airway 16, roof haulage uphill roadway 7, roof track uphill roadway 8, roof return air uphill roadway 9, and top extraction roadways 17 and 20.

[0043] After the mining of coal seam 1, coal seam 2 is depressurized and mined under the protection of the seam. At the same time, regional gas depressurization and extraction are carried out on coal seam 2 in the intake airway 19 and return airway 18 of the working face.

[0044] After the mining of coal seam 2, coal seam 3 is depressurized and mined under the protection of the seam. At the same time, regional gas depressurization and extraction are carried out in coal seam 3 from coal seam 2.

[0045] In addition to being protected by progressively depressurized layers, the gas supply and control of the working face can be carried out through the bottom haulage roadway 3 and the bottom track roadway 4 and / or the bottom haulage uphill roadway 10 and the bottom track uphill roadway 11 and the bottom return air uphill roadway 12 and the bottom return air roadway 15 before the mining operation of coal seam 3.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for large-area gas control through progressive mining of closely spaced, high-risk coal seam groups, characterized in that: The roadway layout and excavation adopt a combined top and bottom roadway arrangement. During the excavation of the top or bottom roadway, directional long boreholes are used in the top roadway to carry out regional gas advance treatment of the first mining face and the mining face. After the first mining face is mined, the lower adjacent layers are progressively advanced to carry out depressurization mining of the protected layer. At the same time, gas comprehensive treatment is carried out in the intake airway and return airway of the working face for the lower adjacent layers until the last coal seam of the coal seam group. Before mining the last coal seam of the coal seam group, while the protected layer is depressurized during mining, regional gas replenishment and treatment are carried out through the bottom roadway for the tunneling and mining faces of the last coal seam of the coal seam group. The combined layout of the top and bottom slab roadways is as follows: In the roof strata of the first mining layer, interconnected roof haulage main roadway, roof track main roadway, roof return air main roadway, roof haulage uphill roadway, roof track uphill roadway and roof return air uphill roadway are arranged in a concentrated manner. The longwall face adopts a double-wing layout. The top extraction roadway is arranged along the roof of the longwall face of the first mining layer. After the section inclined stone gate is made at the opening of the roof track uphill and the roof return air uphill, the longwall face intake roadway and the longwall face return airway are arranged along the longwall face of the first mining layer. In the bottom strata of the last coal seam of the coal seam group, interconnected bottom haulage roadways, bottom track roadways, or bottom haulage uphill roadways, bottom track uphill roadways, bottom return air uphill roadways, and bottom return air roadways are arranged in a concentrated manner. The roof slab transport roadway and the floor slab transport roadway are connected by an air intake stone gate, and the roof slab return air roadway and the floor slab return air roadway are connected by a return air stone gate. A main shaft and an auxiliary shaft are used to connect the roof slab transport roadway and the roof slab track roadway, respectively, to form an intake air system; a return air shaft is used to connect the roof slab return air roadway, to form a return air system.

2. The method for large-area gas control by progressively mining closely spaced, high-risk coal seam groups according to claim 1, characterized in that: In the main haulage roadway, main track roadway, or incline roadway, directional long boreholes are used to advance the regional gas control of the first mining layer for the tunneling and mining faces. At the same time, in the top extraction roadway, cross-layer downward boreholes are used to supplement the gas control of the first mining layer for the tunneling faces.

3. The method for large-area gas control by progressively mining closely spaced, high-risk coal seam groups according to claim 1, characterized in that: Before mining the last coal seam of a coal seam group, regional gas supplementation and control are carried out in the bottom haulage roadway, bottom track roadway, bottom haulage uphill roadway, or bottom track uphill roadway for the tunneling and mining faces of the last coal seam of the coal seam group.

4. The method for large-area gas control by progressively mining closely spaced, high-risk coal seam groups according to claim 1, characterized in that: During the excavation of roof or floor roadways, exploration is conducted simultaneously to obtain information on the structure and undulation of the coal seam, providing data support for coal roadway excavation.

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