Coal mining earthquake prevention method in deep stress concentration area

Abstract

The present application belongs to the field of coal mine earthquake prevention and treatment, and particularly relates to a method for preventing and treating coal mining earthquake in deep stress concentration area. The present application firstly adopts a filling method to mine the coal pillars between two roadways in the coal pillars of the roadways. The coal pillars on both sides of the two roadways can protect safety and prevent mine earthquake from occurring. Meanwhile, the filling body after filling can prevent the formation of isolated coal pillars when the coal pillars on both sides of the two roadways are mined, so as to avoid mine earthquake when the coal pillars on both sides of the two roadways are mined. Only the coal pillars between the two roadways are filled in the whole roadway coal pillars, the filling workload is small, the filling proportion is small, and the mining efficiency of the whole roadway coal pillars is high. The present application ingeniously designs the coal transportation, filling material transportation, pedestrian and ventilation lines, so as to maximize the utilization of the functions of the original roadway.

Description

Technical Field

[0001] This invention belongs to the field of coal mine seismic prevention and control, specifically relating to a method for seismic prevention and control in coal mining in deep stress concentration zones. Background Technology

[0002] Mine seismic activity refers to seismic activity caused by mining operations at ground level or in shallow layers (hundreds of meters to thousands of meters deep). Coal mine seismic activity is characterized by its wide distribution, high frequency, and large magnitude. Mine seismic activity easily induces secondary disasters such as mine rock bursts, gas accidents, dynamic water hazards, and roof collapses. Furthermore, as the depth of coal mining increases, the possibility of mining-induced strong mine seismic activity further increases, seriously threatening safe coal mine production.

[0003] The main roadway in a mine is located at the lowest level of the mining area, serving multiple mining areas. Therefore, the main roadway is relatively deep, making it prone to mine tremors when mining the coal pillars. Furthermore, the coal pillars in the main roadway tend to be located in goaf areas, where stress concentration zones exist, resulting in high energy levels from mine tremors and a greater likelihood of secondary disasters. Therefore, when mining in deep stress concentration zones such as the main roadway pillars, it is crucial to focus on preventing and controlling mine tremors. Summary of the Invention

[0004] To address the technical problem that coal mining in deep stress concentration zones is prone to mine tremors, which can then trigger secondary disasters, this invention proposes a method for preventing mine tremors in coal mining in deep stress concentration zones, specifically including the following steps:

[0005] Step 1: At the boundary of the mine field, excavate a return air incline along the direction of the return air incline from the end of the main track roadway;

[0006] Step 2: Gradually move from the left mining boundary to the minefield boundary, and excavate the mining channels from the main haulage roadway to the coal pillars between the main haulage roadway and the track roadway. Coal pillars are formed between the mining channels. The excavated coal passes through the main haulage roadway and then through the first connecting stone gate and the main shaft.

[0007] After the roadway is excavated, it is filled with paste. After the filling material stabilizes, the coal pillars between the filling materials are excavated. Then, the empty areas of the excavated coal pillars are filled. At certain intervals, one excavated coal pillar is left unfilled to form a connecting roadway. A closed retaining wall is set up in the connecting roadway. The filling material arrives at the main track roadway from the auxiliary shaft and the second connecting stone gate and fills the areas that need to be filled. After filling, the original transport roadway and the main track roadway are retained.

[0008] Workers enter the work area through the auxiliary shaft, the second connecting stone gate, and the main track roadway, and return via the same route after completing their work. One stream of fresh air enters the work area through the main shaft, the first connecting stone gate, and the transport roadway, while another stream of fresh air enters the work area through the auxiliary shaft, the second connecting stone gate, and the main track roadway. After becoming exhaust air, it passes through the main track roadway, then through the return air uphill, the return air roadway, the third connecting stone gate, and the ventilation shaft before being discharged.

[0009] Step 3: Use the auxiliary shaft as a ventilation shaft;

[0010] Step 4: Simultaneously mine the remaining coal pillars in the upper side of the track roadway and the lower side of the transport roadway using the full caving method, and open the closed retaining wall in the connecting roadway closest to the mining area during the mining process; the coal mined from the upper side of the track roadway passes through the connecting roadway and then passes through the transport roadway together with the coal mined from the lower side of the transport roadway, and is then transported out through the first connecting gate and the main shaft.

[0011] Workers enter the mining area via the main shaft, the first connecting gate, and the transport roadway, and return via the same route after completing their work. Fresh air enters the transport roadway via the main shaft and the first connecting gate. Then, some of the fresh air enters the mining area below the transport roadway, becomes exhaust air, and then enters the second connecting gate through the main track roadway via the connecting roadway, and is discharged through the auxiliary shaft. The other part of the fresh air first enters the mining area above the main track roadway via the connecting roadway, becomes exhaust air, and then enters the second connecting gate through the main track roadway and is discharged through the auxiliary shaft.

[0012] Preferably, continuous miners or tunneling machines are used to excavate the main roadway coal pillars.

[0013] Preferably, the width of the roadway interval is the same as the width of the roadway.

[0014] Preferably, a coal pillar is left unfilled every 30m after the roadway has been mined.

[0015] Preferably, at least one mining roadway is retained between the mining roadway and the backfilling area and the backfilled area, and a temporary retaining wall is set between the mining roadway pillar above the retained mining roadway and the track incline; or at least one mining roadway pillar is retained between the mining roadway and the backfilling area and the backfilled area, and a temporary retaining wall is set between the backfilling body above the retained mining roadway pillar and the track incline.

[0016] Preferably, a ventilation duct is used to draw turbid air from the lower side of the transport roadway to the track roadway; fresh air is introduced into the upper side of the track roadway by a fan, and a ventilation duct is used to draw turbid air from the side of the track roadway to the left side of the track roadway.

[0017] Beneficial technical effects: 1. This invention first employs a backfilling method to mine the coal pillar between two main roadways. Protected by the coal pillars on both sides of the two main roadways, safety is ensured and mine vibrations are prevented. Simultaneously, the backfilled material prevents the formation of isolated coal pillars during the mining of the coal pillars on both sides of the two main roadways, thus avoiding mine vibrations during mining. Only the coal pillar between the two main roadways is backfilled, resulting in a small backfilling workload, a small backfilling ratio, and high overall mining efficiency.

[0018] 2. This invention ingeniously designs coal transportation, backfill material transportation, pedestrian and ventilation routes, which can maximize the use of the original roadway functions, especially the scheme of using the auxiliary shaft as a ventilation shaft when mining the main roadway coal pillar by the full caving method. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the coal pillar layout in the main roadway of the present invention;

[0020] Figure 2 This is a schematic diagram of the mining of the middle area of ​​the main roadway coal pillar in this invention;

[0021] Figure 3 This is a schematic diagram of the mining of the area on both sides of the main roadway coal pillar in this invention;

[0022] Figure 4 In this invention Figure 2 Enlarged view of a local area;

[0023] Figure 5 In this invention Figure 3 Enlarged view of a local area;

[0024] In the diagram, 1 is the main roadway coal pillar, 2 is the main shaft, 3 is the auxiliary shaft, 4 is the first connecting stone gate, 5 is the second connecting stone gate, 6 is the track main roadway, 7 is the transport main roadway, 8 is the ventilation shaft, 9 is the third connecting stone gate, 10 is the return air main roadway, 11 is the goaf, 12 is the return air incline, 13 is the roadway mining and filling area, 14 is the filled area, 15 is the connecting roadway, 16 is the filling body, 17 is the closed retaining wall, 18 is the roadway mining coal pillar, 19 is the roadway mining passage, 20 is the temporary retaining wall, 21 is the coal pillar goaf, 22 is the transfer area, and 23 is the mining boundary. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-5 The present invention will be further described below.

[0026] like Figure 1As shown, after coal mining, a goaf 11 was formed in a certain mine. Currently, only the main roadway pillar 1 is feasible for remining. The length direction of the main roadway pillar 1 is basically parallel to the strike. The main roadway pillar 1 also retains the track roadway 6 and the transport roadway 7. Goaf 11 is located on both sides of the main roadway. At the industrial square, there is also the main shaft 2 and the first connecting stone gate 4 connecting the main shaft 2 and the transport roadway 7, as well as the auxiliary shaft 3 and the second connecting stone gate 5 connecting the auxiliary shaft 3 and the track roadway 6. Transfer area 22 is also set on the first connecting stone gate 4 and the second connecting stone gate 5. In addition, the return air roadway 10, the return air shaft 8, and the third connecting stone gate 9 connecting the two are also well preserved. The distance from the boundary of the minefield to the protective coal pillar of the industrial square of the main roadway coal pillar 1 is about 1800m, that is, the length of the main roadway coal pillar is about 1800m and the dip width is 150m. The track roadway 6 is located 50m away from the upper boundary of the main roadway coal pillar, and the transport roadway 7 is located 50m away from the lower boundary of the main roadway coal pillar. The width of both the transport roadway 7 and the track roadway 6 is 5m, and the interval between the transport roadway 7 and the track roadway 6 is 40m.

[0027] The main roadway coal pillar 1 is bordered on both sides by goaf areas 11 formed after the mining of the original longwall working face. Due to the collapse characteristics of the coal mining strata, the weight of the overburden 1 borne by the main roadway coal pillar is greater than the weight of the overburden directly above it. That is, the main roadway coal pillar 1 also bears the weight of the overburden beyond its direct upper surface. The overburden beyond its direct upper surface exists in the form of a cantilever beam, and the main roadway coal pillar 1 is in a stress concentration zone. In addition, the main roadway coal pillar 11 is buried at a relatively deep depth, with an average depth of nearly 600m. Therefore, mining the main roadway coal pillar 1 is prone to mine tremors, which may lead to secondary disasters.

[0028] To address the technical problem of mine tremors easily generated during coal mining in deep stress concentration zones such as main roadway coal pillars, this invention proposes a method for preventing mine tremors during coal mining in deep stress concentration zones, comprising the following steps:

[0029] Step 1: At the boundary of the well field, from the end of the main track roadway 6, along the direction of the return air roadway 10, a return air uphill roadway 12 is formed by excavating along the open roadway;

[0030] Step 2: Determine the left mining boundary 23 of the main roadway coal pillar 1 and the right mining boundary as the minefield boundary;

[0031] Drive the continuous mining machine or tunneling machine into the haulage roadway 7, such as Figure 2 , 4 As shown, from the left mining boundary 23 towards the minefield boundary, the coal pillar between the main transport roadway 7 and the main track roadway 6 is mined using the roadway mining method, and the roadway mining area is filled.

[0032] like Figure 2 , 4As shown, specifically: from the left mining boundary 23 towards the minefield boundary, the coal pillars of the main roadway between the main roadway 7 and the track roadway 6 are successively excavated to form mining channels 19 with a width of 5-6m. The width of the intervals between mining channels 19 is the same as the width of the mining channels 19, which is also 5-6m. Coal pillars 18 are formed between the mining channels 19. The excavated coal passes through the main roadway 7 and then through the first connecting stone gate 4 and the main shaft 2 for transportation out.

[0033] The mined-out voids, i.e., the mined roadways 19, are filled with paste to form a filling body 16. After the filling body 16 stabilizes, continuous miners or tunneling machines are used to mine the coal pillars 18 between the filling bodies 16. Then, the mined-out coal pillar voids are filled, and every 30m, one mined-out coal pillar 18 is left unfilled to form a connecting roadway 15. A closed retaining wall 17 is set up in the connecting roadway. The filling material arrives at the main track roadway 6 from the auxiliary shaft 3 and the second connecting stone gate 5 and then fills the areas that need to be filled. After filling, the original transport roadway 7 and the main track roadway 6 are retained.

[0034] At least one mining passage 19 or a mined coal pillar 18 shall be retained between the mining and filling area 13 and the filled area 14 (the filled area 14 here specifically refers to the area after all mining and filling has been completed without mining coal pillars 18, excluding the connecting roadway 15). A temporary retaining wall 20 shall be set between the mining coal pillar 18 above the retained mining passage 19 and the track incline 9, or a temporary retaining wall 20 shall be set between the filling body 16 above the retained mined coal pillar 18 and the track incline 9.

[0035] Workers enter the work area through auxiliary shaft 3, second connecting stone gate 5, and track main roadway 6, and return via the same route after completing their work. One stream of fresh air enters the work area through auxiliary shaft 2, first connecting stone gate 4, and transport main roadway 7, while another stream of fresh air enters the work area through auxiliary shaft 3, second connecting stone gate 5, and track main roadway 6. After becoming exhaust air, it passes through track main roadway 6 and is discharged via return air uphill 12, return air main roadway 10, third connecting stone gate 9, and ventilation shaft 8.

[0036] Step 3: After the coal pillar between the main transport roadway 7 and the main track roadway 6 is mined in the manner of step 2, the auxiliary shaft 3 will be used as a ventilation shaft. The auxiliary shaft 3 will no longer be used for transporting backfill materials, ventilation, or pedestrian access.

[0037] Step 4: Using a continuous miner or tunneling machine, the remaining coal pillars on the upper side of the main track roadway 6 and the lower side of the main transport roadway 7 are simultaneously mined using the full caving method. During the mining process, the closed retaining wall 17 in the connecting roadway 15 closest to the mining area is opened until the mining boundary 23 is reached. The coal mined on the upper side of the main track roadway 6 passes through the connecting roadway 15 and then passes through the main transport roadway 7 together with the coal mined on the lower side of the main transport roadway 7 before being transported out through the first connecting gate 4 and the main shaft 2.

[0038] Workers enter the mining area via shaft 2, first connecting gate 4, and transport roadway 7, and return via the same route after completing their work. Fresh air enters transport roadway 7 via shaft 2 and first connecting gate 4. Part of the fresh air enters the mining area below transport roadway 7, becomes exhaust air, and then enters the second connecting gate 5 via connecting roadway 15 and then the track roadway 6. It is then discharged via auxiliary shaft 3 (a ventilation duct is used to draw the turbid air from the mining area below transport roadway 7 to track roadway 6). The other part of the fresh air first enters the mining area above track roadway 6 via connecting roadway 15 (fresh air is introduced into the mining area above track roadway 6 using a fan). It becomes exhaust air and then enters the second connecting gate 5 from track roadway 6 and is discharged via auxiliary shaft 3 (a ventilation duct is used to draw the turbid air from the mining area above track roadway 6 to the left side of track roadway 6). The turbid air gathers on the left side of track roadway 6.

[0039] While the present invention has been described above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A method for preventing earthquakes in coal mines located in deep stress concentration zones, characterized in that, Includes the following steps: Step 1: At the boundary of the mine field, excavate a return air incline along the direction of the return air incline from the end of the main track roadway; Step 2: Gradually move from the left mining boundary to the minefield boundary, and excavate the mining channels from the main haulage roadway to the coal pillars between the main haulage roadway and the track roadway. Coal pillars are formed between the mining channels. The excavated coal passes through the main haulage roadway and then through the first connecting stone gate and the main shaft. After the roadway is excavated, it is filled with paste. After the filling material stabilizes, the coal pillars between the filling materials are excavated. Then, the empty areas of the excavated coal pillars are filled. At certain intervals, one excavated coal pillar is left unfilled to form a connecting roadway. A closed retaining wall is set up in the connecting roadway. The filling material arrives at the main track roadway from the auxiliary shaft and the second connecting stone gate and fills the areas that need to be filled. After filling, the original transport roadway and the main track roadway are retained. Workers enter the work area through the auxiliary shaft, the second connecting stone gate, and the main track roadway, and return via the same route after completing their work. One stream of fresh air enters the work area through the main shaft, the first connecting stone gate, and the transport roadway, while another stream of fresh air enters the work area through the auxiliary shaft, the second connecting stone gate, and the main track roadway. After becoming exhaust air, it passes through the main track roadway, then through the return air uphill, the return air roadway, the third connecting stone gate, and the ventilation shaft before being discharged. Step 3: Use the auxiliary shaft as a ventilation shaft; Step 4: Simultaneously mine the remaining coal pillars in the upper side of the track roadway and the lower side of the transport roadway using the full caving method, and open the closed retaining wall in the connecting roadway closest to the mining area during the mining process; the coal mined from the upper side of the track roadway passes through the connecting roadway and then passes through the transport roadway together with the coal mined from the lower side of the transport roadway, and is then transported out through the first connecting gate and the main shaft. Workers enter the mining area via the main shaft, the first connecting gate, and the transport roadway, and return via the same route after completing their work. Fresh air enters the transport roadway via the main shaft and the first connecting gate. Then, some of the fresh air enters the mining area below the transport roadway, becomes exhaust air, and then enters the second connecting gate through the main track roadway via the connecting roadway, and is discharged through the auxiliary shaft. The other part of the fresh air first enters the mining area above the main track roadway via the connecting roadway, becomes exhaust air, and then enters the second connecting gate through the main track roadway and is discharged through the auxiliary shaft.

2. The method for preventing earthquakes in coal mines with deep stress concentration zones according to claim 1, characterized in that, The main roadway coal pillars are mined using continuous miners or tunneling machines.

3. The method for preventing earthquakes in coal mines with deep stress concentration zones according to claim 1, characterized in that, The spacing width of the mining tunnel is the same as the width of the mining tunnel itself.

4. The method for preventing earthquakes in coal mines with deep stress concentration zones according to claim 1, characterized in that, Every 30m, a coal pillar is left unfilled after the roadway has been excavated.

5. The method for preventing earthquakes in coal mines with deep stress concentration zones according to claim 1, characterized in that, At least one mining roadway shall be retained between the mining roadway and the backfilling area and the backfilled area, and a temporary retaining wall shall be set up between the mining roadway pillar above the retained mining roadway and the track incline; or at least one mining roadway pillar shall be retained between the mining roadway and the backfilling area and the backfilled area, and a temporary retaining wall shall be set up between the backfilling body above the retained mining roadway pillar and the track incline.

6. The method for preventing earthquakes in coal mines with deep stress concentration zones according to claim 1, characterized in that, A ventilation duct is used to draw turbid air from the lower side of the transport roadway to the track roadway; fresh air is introduced into the upper side of the track roadway by a fan, and a ventilation duct is used to draw turbid air from the side of the track roadway to the left side of the track roadway.

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