A method for preventing and treating rock burst and mine earthquake in a combined preparation mode of a panel

Abstract

The application discloses a kind of disc area joint preparation mode rock burst and mine shock prevention and control method, comprising the following steps: mine development, along the inclined direction of coal seam at lower coal seam Construction return air roadway, lower air inlet gallery, coal conveying roadway, construction upper air inlet gallery at upper coal seam;Lower coal seam disc area preparation, within the rock stratum collapse angle of working face, construction top extraction roadway in relatively high position in upper coal seam;Lower coal seam disc area mining: during mining, top extraction roadway and gas extraction in gas extraction crossheading are used for gas extraction;Upper coal seam disc area preparation: upper coal seam disc area is arranged corresponding above lower coal seam disc area position, return air crossheading, air inlet crossheading are two top extraction roadways adjacent, transport crossheading is arranged directly above lower coal seam transport crossheading.The disc area joint preparation mode of the application can greatly improve the effect of rock burst and mine shock prevention and control, greatly improve the efficiency of gas extraction and gas control effect, can ensure the demand of high-intensity mining of mine without increasing the amount of roadway construction engineering.

Description

Technical Field

[0001] This invention belongs to the field of coal mine rockburst and mine tremor prevention, specifically a method for rockburst and mine tremor prevention using a panel-based combined preparation approach. Background Technology

[0002] Coal is buried in layers below the earth's surface, forming coal seams. During coal seam mining, the coal seam is subjected to pressure from the overlying strata. When the overall hardness of the overlying strata is relatively high, a large area of ​​the coal seam needs to be mined to cause the overlying strata to fracture. In this case, the overlying strata exist in a cantilever form for a long time and for a long period. This can easily lead to rockbursts in the coal seam mining area and mine tremors within the mining area. Severe mine tremors can endanger the surface. Rockbursts and mine tremors can affect the normal mining of coal seams, endanger the safety of miners, and damage mining equipment. Meanwhile, gas control is also a challenge in mines with rockbursts and seismic activity. Under high pressure, gas is more difficult to escape from the coal seam and harder to extract (pre-mining extraction). This leads to large gas spills during coal mining, causing gas levels to exceed limits at the working face. Gas explosions are a major cause of serious mine accidents. Therefore, in mines with rockbursts and seismic activity, it is crucial to prioritize the prevention and control of rockbursts and seismic activity, and to increase gas control measures. Currently, common methods for these conditions include drilling boreholes within the coal seam for pre-fracture and gas extraction. Pre-fracture disrupts the elasticity of the coal seam, reducing or eliminating its rockburst tendency. Pre-extraction of gas reduces the gas content during mining. Increased ventilation during face mining further extracts any spilled gas. For multi-seam geological conditions, mining the release layer is also an effective method. However, the above-mentioned technology has low construction efficiency, the pre-splitting drilling construction and related procedures in the coal mining process affect each other, the amount of residual gas in the working face and goaf is large after gas pre-drainage, and the gas control is not thorough enough. Summary of the Invention

[0003] To address the problems of large construction workload and incomplete gas control in existing technologies for preventing and controlling rockbursts and mine tremors, this invention proposes a panel-based combined preparation method for preventing and controlling rockbursts and mine tremors, comprising the following steps:

[0004] Mine development: Along the dip direction of the coal seam, construct the return airway, lower intake airway, and coal haulage roadway in parallel at the lower coal seam, and construct the upper intake airway above the lower intake airway at the upper coal seam;

[0005] Preferably, the return air roadway, the lower intake air roadway, and the coal conveying roadway are connected to the return air shaft, the main shaft, and the auxiliary shaft, respectively, while the upper intake air roadway is connected to the auxiliary shaft.

[0006] Preparation of the lower coal seam panel: Several panels are arranged sequentially along the extension direction of the main roadway, and several working faces are arranged in each panel;

[0007] At a relatively high point within the panel, the return air roadway, transport roadway, and intake air roadway are constructed from high to low along the strike. The return air roadway and transport roadway are connected to form the mining area of ​​the working face. The transport roadway and intake air roadway are connected by a connecting roadway. The return air roadway, transport roadway, and intake air roadway are connected to the return air main roadway, coal transport main roadway, and lower intake air main roadway, respectively. Within the strata collapse angle directly above the working face, a top drainage roadway is constructed at a relatively high point within the upper coal seam. The top drainage roadway is connected to the return air main roadway through a vertical first chute, forming the first mining working face within the lower coal seam panel.

[0008] Within the panel area, the remaining working faces are prepared sequentially from high to low along the diagonal direction. The transport roadway of the previous working face serves as the return air roadway of the next working face, and the intake air roadway of the previous working face serves as the gas drainage roadway of the next working face. The transport roadway and intake air roadway are constructed for the next working face, and the gas drainage roadway is connected to the return air main roadway. The top drainage roadway is constructed for the remaining working faces in the same manner as the first mining working face.

[0009] Lower coal seam panel mining: The first mining face is mined, and gas is extracted using the top extraction roadway; the remaining mining faces are mined, and gas is extracted simultaneously using the top extraction roadway and the gas extraction middle roadway during the mining process.

[0010] Preferably, in-seam drilling is carried out in the return air roadway and transport roadway of the first mining face to pre-splitting the lower coal seam in the mining area of ​​the first mining face.

[0011] Preferably, during subsequent face mining, pre-splitting of the lower coal seam is carried out by drilling boreholes along the roadway to both sides during gas drainage.

[0012] Upper coal seam panel preparation: The upper coal seam panel is arranged above the lower coal seam panel.

[0013] At a relatively high point within the panel, return air roadways, haulage roadways, and intake air roadways are arranged from high to low along the strike. The return air roadways and haulage roadways are connected to form the mining area of ​​the working face. The haulage roadways and intake air roadways are connected by connecting roadways. The return air roadway is connected to the return air main roadway through a chute, the haulage roadway is connected to the coal haulage main roadway through a chute, and the intake air roadway is connected to the upper intake air main roadway. The return air roadway and intake air roadway are two adjacent top extraction roadways, and the haulage roadway is arranged directly above the haulage roadway of the lower coal seam, thus forming the first mining face within the panel.

[0014] Within the panel area, the remaining working faces are prepared sequentially from high to low along the inclined direction. The transport roadway of the previous working face serves as the return air roadway of the next working face, and the intake air roadway of the previous working face serves as the gas extraction roadway of the next working face. The transport roadway and intake air roadway are arranged for the next working face. The gas extraction roadway is connected to the return air roadway through the connecting roadway.

[0015] Upper coal seam panel mining: The first mining face is mined, and the remaining mining faces are mined. During the mining process, gas is drained from the gas drainage roadway.

[0016] The same method was used to coordinate the layout of other panels, and the mining of the lower and upper coal seams within the panels was carried out.

[0017] Beneficial effects: The panel-based combined preparation method of the present invention can greatly improve the prevention and control of rock bursts and mine tremors, greatly improve the efficiency of gas extraction and the effect of gas control, and ensure the high-intensity mining needs of the mine without increasing the amount of roadway construction. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the joint preparation method for the panel area of ​​the present invention, showing the arrangement of the roadway.

[0019] Figure 2 This is a plan view of the working face layout of the No. 2 coal seam panel under the panel joint preparation method of the present invention;

[0020] Figure 3 This is a plan view of the working face layout of the No. 1 coal seam panel under the panel joint preparation method of the present invention;

[0021] In the diagram: Coal seam 1#: Working face 1-1, return air roadway 1-2, transport roadway 1-3, intake air roadway 1-4, gas drainage roadway 1-5, connecting roadway 1-6, first ore pass 1-7, intake airway 1-8, second ore pass 1-9; Coal seam 2#: Working face 2-1, return air roadway 2-2, transport roadway 2-3, intake air roadway 2-4, gas drainage roadway 2-5, top drainage roadway 2-6, return airway 2-7, intake airway 2-8, coal transport roadway 2-9; Rock strata collapse angle 3. Detailed Implementation

[0022] The following example uses a coal mine in the Dongsheng Coalfield of Inner Mongolia Autonomous Region, a subsidiary of the group company, in conjunction with the attached... Figure 1-3 The technical solution of the present invention will be described in more detail below.

[0023] The mine has a certified production capacity of 8 million tons per year, recoverable reserves of approximately 1,500 million tons, and a service life of 110 years. Within this service life, the main coal seams to be mined are No. 1 and No. 2. The impact tendency of No. 1 and No. 2 coal seams and their roof and floor strata was assessed. The assessment results show that No. 1 coal seam and its roof and floor strata have a strong impact tendency, and its gas content is classified as high-gas. No. 2 coal seam and its roof and floor strata have a weak impact tendency, and its gas content is also classified as high-gas. The thickness of No. 2 coal seam is 4.4–5.8 m, with an average of 4.9 m, a burial depth of 686–701 m, and a dip angle of 1–5°. The thickness of No. 1 coal seam is 3.8–5.0 m, with an average of 4.2 m, a burial depth of 617–631 m, and a dip angle of 1–4°. The average distance between No. 1 and No. 2 coal seams is 70 m. Based on the geological conditions of coal seams 1 and 2, and after extensive research and evaluation, the mine ultimately adopted a panel-based joint preparation method. In each panel, coal seam 2, which has a relatively weaker tendency to impact, will be mined first. After coal seam 2 is mined, coal seam 1 will be mined. Mining coal seam 2 will relieve pressure on coal seam 1, thus solving the problem of its tendency to impact. In addition, by setting up a top drainage roadway, the gas problem of both coal seams can be solved simultaneously (pre-drainage of coal seam 1 before mining, and drainage during mining of coal seam 2). Both coal seams will be mined using fully mechanized caving mining technology, with the roof managed by the caving method. The detailed plan is as follows.

[0024] Mine Development: Within the mining area, in the middle of the strike (perpendicular to the dip direction) of the No. 2 coal seam, three main roadways are constructed parallel to the dip direction of the No. 2 coal seam: Return Air Roadway 2-7, Intake Air Roadway 2-8, and Coal Transport Roadway 2-9. Return Air Roadway 2-7, Intake Air Roadway 2-8, and Coal Transport Roadway 2-9 are connected to the Return Air Shaft, Main Shaft, and Auxiliary Shaft (not shown in the figure), respectively. In the No. 1 coal seam, along the dip direction of the No. 1 coal seam, Intake Air Roadway 1-8 is constructed directly above Intake Air Roadway 2-8. Intake Air Roadway 1-8 is connected to the Auxiliary Shaft (not shown in the figure).

[0025] Preparation of No. 2 coal seam panel: Several panels are arranged in sequence along the direction of the main roadway extension, that is, along the dip direction of No. 2 coal seam, and several working faces 2-1 are arranged in each panel;

[0026] At a relatively high point within the panel, three roadways are constructed along the strike, from high to low: return air roadway 2-2, transport roadway 2-3, and intake air roadway 2-4. The return air roadway 2-2 and transport roadway 2-3 are connected to form the mining area of ​​working face 2-1. Working face 2-1, including the two side roadways, is 302m wide and approximately 2330m long. The coal pillar width between transport roadway 2-3 and intake air roadway 2-4 is 40m, connected by a connecting... The roadways are connected; the return air roadway 2-2, transport roadway 2-3, and intake air roadway 2-4 are respectively connected to the return air main roadway 2-7, the coal transport main roadway 2-9, and the intake air main roadway 2-8; within the rock strata collapse angle 3 directly above the working face 2-1, in the No. 1 coal seam, a top extraction roadway 2-6 is constructed on the side near the return air roadway 2-2, and the top extraction roadway 2-6 is connected to the return air main roadway 2-7 through the vertical first chute 1-7; thus forming the first mining working face in the panel area;

[0027] Arranging the top drainage roadway 2-6 within the strata collapse angle 3 of the No. 2 coal seam can greatly improve the gas extraction within the No. 2 coal seam and the gas extraction from the goaf of the No. 2 coal seam during the mining of the No. 2 coal seam. At the same time, the top drainage roadway 2-6 is arranged in the No. 1 coal seam. Due to the pressure relief brought about by the mining of the No. 2 coal seam, the top drainage roadway 2-6 can pre-drain the gas in the No. 1 coal seam. Subsequently, the mining of the No. 1 coal seam can proceed directly without pre-draining the gas. More importantly, the top drainage roadway 2-6 is arranged in the No. 1 coal seam and can also be used as a mining roadway during the mining of the No. 1 coal seam. This improves the gas extraction effect while reducing the total amount of construction work. This is the important inventive point of this invention.

[0028] Within the panel, prepare the remaining working faces 2-1 sequentially from high to low along the dip direction. The transport roadway 2-3 of the previous working face serves as the return air roadway 2-2 of the next working face, and the intake air roadway 2-4 of the previous working face serves as the gas drainage roadway 1-5 of the next working face. The connection method of the transport roadway 2-3, intake air roadway 2-4, return air roadway 2-2, transport roadway 2-3, and intake air roadway 2-4 for the next working face is the same as that of the first mining working face. At the same time, connect the gas drainage roadway 2-5 to the return air main roadway 2-7. The top drainage roadway 2-6 of the remaining working faces within the panel is constructed in the same way as that of the first mining working face.

[0029] The mine's production capacity needs to reach 8 million tons per year, which is a very large capacity. Therefore, it is essential to ensure mining efficiency. Thus, the working faces (including 1-1 and 2-1) in this invention adopt a 3-way roadway arrangement to reduce interference between various construction processes. The transport roadway 2-3 of the previous working face serves as the return air roadway 2-2 of the next working face, and the intake air roadway 2-4 of the previous working face serves as the gas drainage roadway 1-5 of the next working face. This can reduce the amount of roadway construction work and improve the coal recovery rate. In addition, the setting of the gas drainage roadway 1-5 can further improve the pre-splitting effect and gas drainage effect of the working face. This is the second important inventive point of this invention.

[0030] Mining of Coal Seam #2: The first mining face of coal seam #2 will be mined. As the first mining face within the panel, it causes minimal disturbance to the strata, minimizing the possibility of rockbursts or mine tremors. Therefore, conventional mining methods can be used for the first mining face. However, to further reduce the possibility of rockbursts, this embodiment involves drilling along the seam into the mining area of ​​the first mining face within the return airway 2-2 and transport roadway 2-3 to perform pre-splitting work on the coal seam #2. To reduce its tendency to impact; during the mining process of the first mining face, the gas generated during the mining of No. 2 coal seam is extracted using the top extraction roadway 2-6. At the same time, after the mining of No. 2 coal seam, the overlying rock strata and No. 1 coal seam will collapse and subside, thus relieving pressure. Affected by the mining of No. 2 coal seam, the gas in No. 1 coal seam will gush out from No. 1 coal seam after the pressure is relieved, and be extracted together from the top extraction roadway 2-6. That is, the mining of No. 2 coal seam will simultaneously solve the rock pressure and gas problems of the overlying No. 1 coal seam.

[0031] The mining of the remaining working face 2-1 within the panel area will be carried out. As the mining range increases, the possibility of rock bursts and mine tremors will increase. In the gas drainage roadway 2-5, boreholes will be drilled along the seam to both sides of the working face to carry out pre-splitting work on the No. 2 coal seam in order to reduce its rock burst tendency. During the mining of the working face, gas drainage will be carried out simultaneously using the top drainage roadway 2-6 and the gas drainage roadway 2-5.

[0032] Preparation of No. 1 coal seam panel: The No. 1 coal seam panel is arranged above the No. 2 coal seam panel, and several working faces 1-1 are arranged in each panel; forming a joint preparation method for the panel. Since the distance between No. 1 coal seam and No. 2 coal seam is large, the joint preparation method of the panel in this patent is more reflected in the joint arrangement of the development of the main roadway and the special arrangement of the top extraction roadway 2-6.

[0033] At a relatively high point in the panel, three roadways are arranged along the strike, from high to low: return air roadway 1-2, haulage roadway 1-3, and intake air roadway 1-4. The return air roadway 1-2 and haulage roadway 1-3 connect to form the mining area of ​​working face 1-1, with a total width of 251m including the two side roadways and a mining length of approximately 2330m. The coal pillar width between haulage roadway 1-3 and intake air roadway 1-4 is 51m, connected by a connecting roadway. Return air roadway 1-2 is connected to the main return air roadway 2-7 in the No. 2 coal seam via the vertical first chute 1-7. haulage roadway 1-3 is connected via a vertical... The straight second chute 1-9 connects to the coal transport roadway 2-9 in the No. 2 coal seam, and the intake airway 1-4 connects to the intake airway 1-8 in the No. 1 coal seam. Among them, the return airway 1-2 and the intake airway 1-4 are two adjacent top extraction roadways 2-6. The transport roadway 1-3 is arranged directly above the transport roadway 2-3 in the No. 2 coal seam. Since the transport roadway 1-3 undertakes the high-load work of transporting coal, it is selected outside the strata collapse angle of the adjacent working face of the No. 2 coal seam. This location is less affected by the mining of the No. 2 coal seam, which is conducive to the maintenance of the roadway stability, thus forming the first mining working face in the panel.

[0034] Within the panel area, the remaining working faces 1-1 are prepared sequentially from high to low along the diagonal direction. The transport roadway 1-3 of the previous working face serves as the return air roadway 1-2 of the next working face, and the intake air roadway 1-4 of the previous working face serves as the gas drainage roadway 1-5 of the next working face. The connection method of the transport roadway 1-3, intake air roadway 1-4, return air roadway 1-2, transport roadway 1-3, and intake air roadway 1-4 for the next working face is the same as that of the first working face. At the same time, the gas drainage roadway 1-5 is connected to the return air roadway 1-2 through the connecting roadway 1-6. The mining area of ​​the subsequent working face includes the width of the roadways on both sides, totaling 308m.

[0035] The roadway of the upper No. 1 coal seam of this invention can make full use of the top extraction roadway. Since there are no residual coal pillars in the panel after the No. 2 coal seam is mined, arranging the transport roadway of the No. 1 coal seam directly above the transport roadway of the No. 2 coal seam can make the transport roadway of the No. 1 coal seam located outside the rock strata collapse angle of the adjacent working face of the No. 2 coal seam. This location is less affected by the mining of the No. 2 coal seam, which is conducive to the maintenance of the stability of the roadway. However, if there are residual coal pillars in the No. 2 coal seam, this arrangement is actually not conducive to the stability of the transport roadway of the No. 1 coal seam, because this is a stress concentration area. This is the third inventive point of this invention.

[0036] The two-layer coal seam main roadway layout of this invention is as follows: three main roadways are arranged for the No. 2 coal seam, and only one intake airway is arranged for the No. 1 coal seam. The intake airway is then connected to the No. 2 coal seam's coal transport roadway and return airway via a chute. In this way, the coal conveyor belt only needs to be arranged in the No. 2 coal seam's transport roadway, reducing equipment investment. The No. 1 coal seam does not have a coal transport roadway or return airway, which can reduce the amount of main roadway development work. The reason for arranging one intake airway in the No. 1 coal seam is that the intake airway also undertakes the function of auxiliary material transport. Materials (such as support materials and production consumables) in the intake airway need to be transported from the transport roadway to the working face. However, it is easy to transport materials from top to bottom through the chute (for example, the coal mined from the No. 1 coal seam is directly transported to the No. 2 coal seam's transport roadway by its own weight through the chute), while it is difficult and inefficient to transport materials from bottom to top. Therefore, one transport roadway is arranged in the No. 1 coal seam. This four-main-roadway layout for the two coal seams is the fourth inventive point of this invention.

[0037] Mining of No. 1 coal seam panel: The first mining face of No. 1 coal seam is being mined. Due to the mining of No. 2 coal seam, the pressure of No. 1 coal seam has been relieved, and the gas has been pre-extracted through the top extraction roadway 2-6. Therefore, there is no need to continue the pre-splitting and extraction work, and normal mining can be carried out.

[0038] The remaining working faces 1-1 within the panel area will be mined. During the mining process, gas will be extracted using the gas extraction roadway 1-5.

[0039] The other panels were arranged in the same manner, and the No. 2 and No. 1 coal seams within the panels were mined.

[0040] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for preventing rockbursts and mine tremors through a combined preparation approach in a mining panel, characterized in that, Includes the following steps: Mine development: Along the dip direction of the coal seam, construct the return airway, lower intake airway, and coal haulage roadway in parallel at the lower coal seam, and construct the upper intake airway above the lower intake airway at the upper coal seam; Preparation of the lower coal seam panel: Several panels are arranged sequentially along the extension direction of the main roadway, and several working faces are arranged in each panel; At a relatively high point within the working face, the return air roadway, transport roadway, and intake air roadway are constructed from high to low along the strike. The return air roadway and transport roadway are connected to form the mining area of ​​the working face. The transport roadway and intake air roadway are connected by a connecting roadway. The return air roadway, transport roadway, and intake air roadway are connected to the main return air roadway, main coal transport roadway, and lower intake air roadway, respectively. At a relatively high point within the strata collapse angle directly above the working face, a top drainage roadway is constructed within the upper coal seam. The top drainage roadway is connected to the main return air roadway via a vertical first chute, forming the first mining face within the lower coal seam panel. The top drainage roadway is used as the mining roadway for the working face during the mining of the upper coal seam. Within the panel area, the remaining working faces are prepared sequentially from high to low along the diagonal direction. The transport roadway of the previous working face serves as the return air roadway of the next working face, and the intake air roadway of the previous working face serves as the gas drainage roadway of the next working face. The transport roadway and intake air roadway are constructed for the next working face, and the gas drainage roadway is connected to the return air main roadway. The top drainage roadway is constructed for the remaining working faces in the same manner as the first mining working face. Lower coal seam panel mining: The first mining face is mined, and gas is extracted using the top drainage roadway; the remaining mining faces are mined, and during the mining of the remaining mining faces, in-seam boreholes are drilled to both sides in the gas extraction roadway to carry out pre-splitting work on the lower coal seam. During the mining of the remaining mining faces, gas extraction is carried out simultaneously using the top drainage roadway and the gas extraction roadway; after the lower coal seam is mined, there are no residual coal pillars in the panel. Upper coal seam panel preparation: The upper coal seam panel is arranged above the lower coal seam panel. At a relatively high point within the panel, return air roadways, haulage roadways, and intake air roadways are arranged from high to low along the strike. The return air roadways and haulage roadways are connected to form the mining area of ​​the working face. The haulage roadways and intake air roadways are connected by connecting roadways. The return air roadway is connected to the return air main roadway through a chute, the haulage roadway is connected to the coal haulage main roadway through a chute, and the intake air roadway is connected to the upper intake air main roadway. The return air roadway and intake air roadway are two adjacent top extraction roadways, and the haulage roadway is arranged directly above the haulage roadway of the lower coal seam, thus forming the first mining face within the panel. Within the panel area, the remaining working faces are prepared sequentially from high to low along the dip direction. The transport roadway of the previous working face serves as the return air roadway of the next working face, and the intake air roadway of the previous working face serves as the gas drainage roadway of the next working face. Transport roads and intake air roads are arranged for the next working face. The gas drainage roadway is connected to the return air roadway through a connecting roadway. The transport roadway of the upper coal seam is arranged directly above the transport roadway of the lower coal seam. Upper coal seam panel mining: The first mining face is mined, and the remaining mining faces are mined. During the mining process, gas is drained from the gas drainage roadway. The same method was used to coordinate the layout of other panels, and the mining of the lower and upper coal seams within the panels was carried out.

2. The method for preventing rockbursts and mine tremors according to claim 1, characterized in that, During mine development, the return airway, lower intake airway, and coal transport airway are connected to the return air shaft, main shaft, and auxiliary shaft, respectively, while the upper intake airway is connected to the auxiliary shaft.

3. The method for preventing rockbursts and mine tremors according to claim 1, characterized in that, During the mining of the lower plate area, in-seam drilling is carried out in the return air roadway and transport roadway of the first mining face to pre-splitting the lower coal seam in the mining area of ​​the first mining face.

Images