Green mining method of coordinating caving of adjacent longwall face with filling

Abstract

This invention relates to the field of coal mining technology, specifically to a green mining method that coordinates caving and backfilling of adjacent longwall faces. The method involves dividing the mining face of the mining area into a first, second, and third mining face along its width. The second mining face has a face length greater than both the first and third mining faces. The first and third mining faces utilize a caving method to treat the goaf, while the second mining face utilizes a backfilling method. This green mining method, which coordinates caving and backfilling of adjacent longwall faces, can avoid ground subsidence, improve coal mining efficiency, and reduce mining costs.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, specifically to a green mining method that coordinates the collapse and backfilling of adjacent longwall working faces. Background Technology

[0002] Calcutting mining causes the goaf to collapse, leading to rock strata damage and surface subsidence. Backfilling mining can fill the goaf to support the roof, thus preventing surface subsidence and aquifer damage. However, backfilling mining requires filling the goaf, reducing coal mining efficiency and incurring high costs. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a green mining method that coordinates the collapse and backfilling of adjacent longwall working faces, which can avoid ground subsidence, improve coal mining efficiency, and reduce mining costs.

[0004] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces according to embodiments of the present invention includes:

[0005] The mining face of the mining area is divided into a first mining face, a second mining face, and a third mining face along the width direction. The length of the second mining face is greater than the length of the first mining face and the length of the third mining face. The first mining face and the third mining face are treated by the caving method, and the second mining face is treated by the filling method.

[0006] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces according to embodiments of the present invention can avoid ground subsidence, improve coal mining efficiency, and reduce mining costs.

[0007] In some embodiments, the mining area includes a return airway and a haulage airway. The return airway is located between the first mining face and the second mining face, and is connected to the main return airway. The haulage airway is located between the second mining face and the third mining face, and is connected to the main haulage airway.

[0008] A return airway is arranged during the mining of the first mining face, and a transport airway is arranged during the mining of the third mining face. Supports are provided for the return airway and the transport airway.

[0009] The embodiments of the present invention propose a green mining method that coordinates the collapse and backfilling of adjacent longwall working faces, which can avoid ground subsidence, improve coal mining efficiency, and reduce mining costs.

[0010] In some embodiments, roadway filling bodies are provided in transport roadways and return air roadways, and surface filling stations and underground filling stations are provided to fill the roadway filling bodies. The roadway filling bodies isolate the goaf of the second mining face from the transport roadway or return air roadway.

[0011] In some embodiments, the second mining face is filled using both surface filling stations and underground filling stations.

[0012] In some embodiments, the first, second, and third mining faces all employ an advancing mining method.

[0013] The first and third mining faces were mined before the second mining face. During the mining of the first mining face, return airways were arranged, roadway supports were provided, and the roadway filling materials in the transport roadway and return airway were filled.

[0014] When mining the second mining face, the goaf area of ​​the second mining face is filled.

[0015] In some embodiments, the distance between the coal mining sites of the first and second mining faces in the direction of the mining area extension is A, and 100m ≤ A ≤ 200m.

[0016] The distance between the coal mining area of ​​the third mining face and the coal mining area of ​​the second mining face in the direction of the mining area extension is B, and 100m≤B≤200m.

[0017] In some embodiments, both the first and third mining faces employ forward mining, while the second mining face employs backward mining.

[0018] During the first mining operation, a return airway is constructed, roadway support is provided, and the roadway filling material within the return airway is filled.

[0019] During the mining of the third mining face, a transport roadway is arranged, roadway support is provided, and the roadway filling material in the transport roadway is filled.

[0020] In some embodiments, the length of the second mining face is c, and c satisfies 450m≥b≥200m. The dimension of the transport roadway in the width direction of the mining face is d, and the dimension of the return air roadway in the width direction of the mining face is e. Then d and e satisfy: 5m≤d=e≤7m.

[0021] In some embodiments, the first mining face, the second mining face, and the third mining face all adopt a retreat mining method, excavating the transport roadway and return air roadway in advance, filling the roadway filling body in the return air roadway and the transport roadway, and then starting the mining of the first mining face, the second mining face, and the third mining face.

[0022] In some embodiments, when the caving method is used to treat the first and third mining faces, as coal mining progresses, the rock strata above the goaf fracture and collapse. However, there is always a stable rock stratum, and regardless of the advancing distance, the fracture height of the rock stratum in the vertical direction no longer increases.

[0023] The rock strata above the goaf fractured and collapsed with a fracture angle. The coal mine roof fractured in the shape of a trapezoidal platform. The base angle of the trapezoidal platform is set as the rock strata fracture angle. The rock strata are numbered sequentially upwards from the coal seam, with the stratum number set as i, where i is 1, 2, etc. ,j,..., , ,

[0024] ,

[0025] in, This represents the ultimate fracture length of the rock strata unaffected by boundaries, indicating the minimum span of the rock strata. For the tensile strength of the rock strata, To bear the load for the (n+1)th rock layer. To stabilize the thickness of the rock strata in the vertical direction,

[0026] ,in W j The sag in the direction of the coal mining face. The value represents the thickness of the rock strata, and the subscript indicates the stratigraphic position. Number the highest rock stratum where the fracture occurred. The height of the trapezoidal truncated cone.

[0027] Let the length of the first mining face be 'a', and the length of the third mining face be 'b', where a and b satisfy: a = b < And 50m≤a=b≤80m.

[0028] In some embodiments, after the second mining face has been mined a predetermined distance, the goaf of the second mining face is filled. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the mining face according to an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the mining face according to an embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of the mining face in an embodiment of the present invention, and the second mining face adopts a retreating mining method.

[0032] Figure 4This is a cross-sectional view of the mining face according to an embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of the first mining face in an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the second mining face according to an embodiment of the present invention.

[0035] Figure label:

[0036] First mining face 1, first goaf 101

[0037] Second mining face 2, second goaf 201

[0038] Third mining face 3, third goaf 301

[0039] Return airway 4, transport airway 5, airway filling material 6, first airway filling material 61, second airway filling material 62.

[0040] The mining face is 10, the return airway is 20, the transport airway is 30, and the mining area is 40. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0042] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces according to embodiments of the present invention includes:

[0043] The mining face 10 of mining area 40 is divided into a first mining face 1, a second mining face 2, and a third mining face 3 along the width direction. The length of the second mining face 2 is greater than the length of the first mining face 1 and the length of the third mining face 3.

[0044] The first mining face 1 and the third mining face 3 use the caving method to treat the goaf, while the second mining face 2 uses the filling method to treat the goaf.

[0045] Specifically, such as Figures 1 to 6 As shown, the width direction of the mining face 10 is the left-right direction, the extension direction of the mining face 10 is the front-back direction, the height direction of the mining face 10 is the up-down direction, and the coal mining direction is the front-back direction.

[0046] From left to right, the working faces are designated as the first working face 1, the second working face 2, and the third working face 3. The first working face 1 or the third working face 3 will use the caving method to treat the roof, while the second working face 2 will use the filling method. The goaf formed after the third working face 3 is designated as the third goaf 301, the goaf formed after the first working face 1 is designated as the first goaf 101, and the goaf formed after the second working face 2 is designated as the second goaf 201. The second goaf 201 is filled to support the roof above the second goaf 201, or it can be understood as supporting the rock strata above the second goaf 201. That is, the filled second goaf 201 supports the upper rock. The second mining face 2 has a face length greater than the first mining face 1 and the third mining face 3. That is, the dimension of the second mining face 2 in the left and right direction is greater than the dimension of the first mining face 1 and the third mining face 3 in the left and right direction. Furthermore, after the filling of the second goaf 201 is completed, it not only supports the rock strata in contact with the filling material of the second goaf 201, but also supports the rock strata above the rock strata in contact with the filling material of the second goaf 201. Since the rock strata above mining area 40 are of the same layer and are integral, the filling material of the second goaf 201 provides support to a certain extent for the rock strata of the first goaf 101 and the third goaf 301, reducing the extent of fractures and collapses in the rock strata of the first goaf 101 and the third goaf 301.

[0047] Furthermore, the size of the second goaf 201 in the left-right direction is larger than that of the first goaf 101 and the second goaf 201 in the left-right direction. That is, the small goaf is collapsed and the large goaf is filled.

[0048] It should be noted that the first mining face 1, the second mining face 2, and the third mining face 3 can be mined simultaneously, or they can be mined at different times.

[0049] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces according to embodiments of the present invention involves collapsing the first goaf 101 and the third goaf 301 and backfilling the second goaf 201. After the second mining area 402 is backfilled, it provides a certain support for the first goaf 101 and the third goaf 301, thus eliminating the need to leave coal pillars and the need to backfill the entire mining area 40. This can avoid ground subsidence, improve coal mining efficiency, reduce mining costs, and increase the coal recovery rate.

[0050] In some embodiments, the mining area 40 is provided with a return airway 4 and a transport airway 5. The return airway 4 is located between the first mining face 1 and the second mining face 2, and is connected to the main return airway 20. The transport airway 5 is located between the second mining face 2 and the third mining face 3, and is connected to the main transport airway 30.

[0051] During the mining of the first mining face 1 or the mining of the second mining face 2, a return airway 4 is arranged. During the mining of the second mining face 2 or the mining of the third mining face 3, a transport airway 5 is arranged to support the return airway 4 and the transport airway 5.

[0052] Specifically, such as Figures 1 to 6 As shown, mining area 40 is equipped with a return airway 4 and a transport roadway 5, which extend in the front-to-back direction. Return airway 4 is located between the first mining face 1 and the second mining face 2, and is used for ventilation of mining area 40. Transport roadway 5 is located between the second mining face 2 and the third mining face 3, and is used for transporting materials and conveying coal. During mining at the first mining face 1, after the coal mining machine has finished mining, it advances in the mining direction, and the anchor bolt support machine supports either transport roadway 5 or return airway 4. That is, the roadway is formed by the coal mining machine cutting coal. Support construction equipment is deployed in ventilation roadway 4 to support return airway 4 and transport roadway 5. For example, anchor bolting machines can be used to achieve anchor bolt support, or existing support devices or equipment such as scaffolding or roadway supports can be used to support the sides of transport roadway 5 and return airway 4. This allows for the simultaneous mining of the first mining face 1 and the third mining face 3, and the simultaneous deployment of roadways, i.e., the deployment of transport roadway 5 and return airway 4, to facilitate coal transportation from the second mining face 2 and to provide ventilation for mining area 40, preventing excessively high concentrations of methane or carbon dioxide within mining area 40.

[0053] Meanwhile, transport roadway 5 and return air roadway 4 can also be used to transport backfill materials, which can then be used to fill and grout the second goaf 201 of the second mining face 2, improving mining efficiency. At the same time, after coal mining in the first mining face 1 and the third mining face 3, support is provided to avoid the cross-operation of coal cutting and support, saving roadway support time and preventing coal cutting from affecting roadway support, or vice versa.

[0054] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces in this invention involves deploying support construction equipment in the roadway after mining in the first and third working faces 1 and 3. This equipment includes anchor bolt support, canopy support, or roadway supports to support the return airway 4 or transport roadway 5, thereby facilitating the transportation of coal during construction and preventing excessive concentrations of methane or carbon dioxide in the mining area 40. After the coal is dropped by the mining machine, support is provided by the anchor bolt machine, achieving non-overlapping operations between coal dropping and support, thus improving mining efficiency.

[0055] In some embodiments, a roadway filling body 6 is provided in the transport roadway 5 and the return air roadway 4, and a surface filling station and an underground filling station are provided to fill the roadway filling body 6. The roadway filling body 6 isolates the goaf of the second mining face 2 from the transport roadway 5 or the return air roadway 4.

[0056] Specifically, such as Figures 1 to 6 As shown, a roadway filling body 6 is arranged in the transport roadway 5 adjacent to the first mining face 1, and a roadway filling body 6 is arranged on the side of the return air roadway 4 adjacent to the third mining face 3. The roadway filling body 6 in the transport roadway 5 is designated as the first roadway filling body 61, and the roadway filling body 6 in the return air roadway 4 is designated as the second roadway filling body 62. The first roadway filling body 61 and the second roadway filling body 62 extend in the front-back direction. The first roadway filling body 61 supports the roof of the mining area 40, that is, it supports the rock strata above the mining area 40, thereby preventing rock strata fracture and collapse, and preventing ground subsidence. Similarly, the second roadway filling body 62 supports the roof of the mining area 40, that is, it supports the rock strata above the mining area 40, thereby preventing rock strata fracture and collapse, and preventing ground subsidence.

[0057] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces in this embodiment of the invention uses a roadway backfill body 6 to support the rock strata above the mining area 40, thus preventing rock strata fracture and collapse. This eliminates the need to leave coal pillars to support the rock strata above the mining area 40, thereby increasing the coal mining rate. It also eliminates the need to excavate the transport roadway 5 and return air roadway 4 separately in advance, thereby reducing coal mining costs.

[0058] Furthermore, the second mining face 2 is filled using both surface and underground filling stations. The existing surface and underground filling stations are used to fill the roadway filling body 6. This can be understood as the surface and underground filling stations providing the filling material, which can be a mixture of mine gangue, municipal waste, sand, etc. However, when filling the roadway filling body 6, cement grouting can be used to improve its strength.

[0059] In some embodiments, the first mining face 1, the second mining face 2, and the third mining face 3 all employ an advancing mining method.

[0060] The first mining face 1 and the third mining face 3 were mined before the second mining face 2. During the mining of the first mining face 1, a return airway 4 was arranged and roadway support was provided.

[0061] During the mining of the third working face 3, a transport roadway 5 is arranged, roadway support is provided, and the roadway filling material 6 in the transport roadway 5 and return air roadway 4 is filled.

[0062] When mining the second mining face 202, the goaf of the second mining face 202 is filled.

[0063] Specifically, such as Figures 1 to 6 As shown, the first mining face 1 employs an advancing mining method. For example, the first mining face 1 begins mining from one end adjacent to the haulage roadway 30 and the return air roadway 20, and proceeds away from the haulage roadway 30 and the return air roadway 20. That is, the first mining face 1 mines from the rear end to the front end of the mining area 40. Similarly, the third mining face 3 employs an advancing mining method. For example, the first mining face 3 begins mining from one end adjacent to the haulage roadway 30 and the return air roadway 20, and proceeds away from the haulage roadway 30 and the return air roadway 20. That is, the third mining face 3 mines from the rear end to the front end of the mining area 40.

[0064] During the mining of the first mining face 1, after the coal chuck completes its coal cutting operation, the bolting machine provides bolt support for the return airway 4. Similarly, during the mining of the third mining face 3, after the coal chuck completes its coal cutting operation, the bolting machine provides bolt support for the transport airway 5. Then, the second mining face 2 begins mining from the rear end of mining area 40 towards the front end.

[0065] Furthermore, the first mining face 1 and the third mining face 3 are mined simultaneously, with the return airway 4 or haulage roadway 5 supported simultaneously, and the roadway backfill 6 within the return airway 4 or haulage roadway 5 being filled simultaneously. When the second mining face 2 is mined, the roadway backfill at both ends of the coal mining area 2 has already been injection molded to support the rock strata above the mining area 40, improving the stability and safety of coal mining. Alternatively, after the first mining face 1 and the third mining face 3 are completed, and the roadway backfill 6 within the return airway 4 or haulage roadway 5 is filled, the second mining face 2 can be mined. This can further improve the stability and safety of coal mining. The coal mining area refers to the position where the coal mining machine cuts coal.

[0066] Understandably, the first mining face 1 and the third mining face 3 can be mined first. During the mining of the first mining face 1, a return airway 4 can be laid out, and during the mining of the third mining face 3, a transport airway 5 can be laid out. After the first mining face 1 and the third mining face 3 have been mined for a certain distance, the first roadway backfill 61 and the second roadway backfill 62 can be filled to prevent collapses in the first goaf 101 and the third goaf 301 from impacting the transport airway 5 or the return airway 4. This will protect the personnel and equipment in the transport airway 5 and the return airway 4, improving the stability and safety of coal mining.

[0067] In some embodiments, the distance between the coal mining area of ​​the first mining face 10 and the coal mining area of ​​the second mining face 2 in the extension direction of the mining area 40 is A, and 100m≤A≤200m.

[0068] The distance between the third mining face 3 and the second mining face 2 in the extension direction of mining area 40 is B, and 100m≤B≤200m.

[0069] Specifically, such as Figures 1 to 6 As shown, the first mining face 1 and the third mining face 3 are mined before the second mining face 2 to facilitate the advance arrangement of the haulage roadway 5 and the return air roadway 4. After the first mining face 1 and the third mining face 3 advance 100 to 200 meters, mining of the second mining face 2 begins. It is understandable that in actual backfilling, the lengths of the first mining face 1 and the third mining face 3 also need to be considered on-site.

[0070] When the length of the first mining face 1 and the third mining face 3 is 80 meters, after the third mining face 3 and the first mining face 1 advance 100 meters, the second mining face 2 and the filling of the second goaf 201 are started.

[0071] When the lengths of the first mining face 1 and the third mining face 3 are both 50 meters, after the third mining face 3 and the first mining face 1 have advanced 200 meters, the second mining face 2 and the filling of the second goaf 201 will commence. This is to prevent the collapse of the first goaf 101 and the third goaf 301 from impacting the second goaf 201, thereby improving the stability and safety of the mining area 40 during on-site coal mining.

[0072] Understandably, after the first mining face 1 and the third mining face 3 have advanced 30 to 60 meters, the roadway filling body 6 in the transport roadway 5 and the return air roadway 4 will be filled. In actual roadway filling, the lengths of the first mining face 1 and the third mining face 3 also need to be considered on-site. When the length of the first mining face 1 and the third mining face 3 is 50 meters, the roadway filling body 6 will be grouted and filled after the third mining face 3 and the first mining face 1 have advanced 30 meters. When the length of the first mining face 1 and the third mining face 3 is 80 meters, the roadway filling body 6 will be filled after the third mining face 3 and the first mining face 1 have advanced 60 meters.

[0073] The green mining method for coordinating the collapse and filling of adjacent longwall working faces in this invention, by setting the distance between the coal mining sites of the first mining face 1 and the second mining face 2 in the extension direction of the mining area 40, and the distance between the coal mining site of the third mining face 3 and the coal mining site of the second mining face 2 in the extension direction of the mining area 40, after the first mining face 1 and the third mining face 3 have been mined first, the mining of the second mining face 2 is started after the first mining face 1 and the third mining face 3 have been mined for a preset distance. This avoids the impact on the second goaf 201 when the first goaf 101 and the third goaf 301 collapse, and improves the stability and safety of the mining area 40 during on-site coal mining.

[0074] In some embodiments, both the first mining face 1 and the third mining face 3 adopt forward mining, while the second mining face 2 adopts backward mining. When mining the first mining face 1, a return airway 4 is arranged for roadway support, and the roadway filling body 6 in the return airway 4 is filled. When mining the third mining face 3, a transport roadway 5 is arranged for roadway support, and the roadway filling body 6 in the transport roadway 5 is filled.

[0075] Specifically, such as Figures 1 to 6 As shown, both the first mining face 1 and the third mining face 3 adopt the forward mining method. After the mining of the first mining face and the third mining face 3 are completed, the support of the haulage roadway 5 and the return air roadway 4 is completed, and the roadway filling body 6 of the return air roadway 4 and the haulage roadway 5 is filled to support the rock strata above the haulage roadway 5 and the return air roadway 4, so as to prevent the collapse of the first goaf 101 and the third goaf 301 from entering the haulage roadway 5 and the return air roadway 4.

[0076] The third mining face 3 is mined using a retreating mining method, proceeding from the front end of mining area 40 to the rear end. Mining equipment is arranged at the front end of mining area 40. The return airway 4 is used for ventilation and material preparation before mining in the third mining face 3. The transport roadway 5 is used for transporting coal after mining, transporting the coal to the main transport roadway 30.

[0077] The green mining method for coordinating the collapse and backfilling of adjacent longwall working faces in this embodiment of the invention adopts forward mining for both the first mining face 1 and the third mining face 3. During mining, roadways are arranged, namely, transport roadways 5 and return airways 4. Before mining the second mining face 2, materials are transported through the return airway 4. During mining the second mining face 2, coal is transported through the transport roadway 5. The coal mined from the second mining face 2 is transported, thus eliminating the need to excavate roadways in advance to form transport roadways 5 or return airways 4, reducing costs. Furthermore, after arranging the roadway backfill body 6, there is no need to leave coal pillars, increasing the coal mining output of the mining area 40.

[0078] In some embodiments, the length of the second mining face 2 is c, and c satisfies 450m≥b≥200m. The dimension of the transport roadway 5 in the width direction of the mining face 10 in the mining area 40 is d, and the dimension of the return air roadway 4 in the width direction of the mining face 10 in the mining area 40 is e. Then d and e satisfy: 5m≤d=e≤7m.

[0079] Specifically, such as Figures 1 to 6 As shown, the dimension of the second mining face 2 in the left-right direction is c, and c satisfies 450m ≥ c ≥ 200m. Therefore, the length of the second mining face 2 can be set to increase the coal extraction rate. The length of the second mining face 2 can be 450m, 430m, 400m, 350m, 300m, 290m, 230m, 240m, 220m, 210m, or 200m. By setting the length of the second mining face 2 in the left-right direction, excessive length of the second mining face 2 avoids excessively high backfilling costs and also avoids the limited support of the backfilled second goaf 201 for the rock strata above mining area 40. Conversely, excessively short length of the second mining face 2 avoids the collapse of the first goaf 101 and the third goaf 301, leading to ground subsidence. At the same time, it avoids the second mining face 2 being too short, which would result in the mining area 40 being small in the left and right directions. This can control the coal mining cost and prevent the ground corresponding to the coal mining from subsiding.

[0080] The lateral spacing of transport roadway 5 is d, and the lateral spacing of return airway 4 is e. d and e satisfy the condition: 5m ≤ d = e ≤ 7m. For example, d and e can be 5m, 5.5m, 6.2m, 6.5m, or 7.0m, arranged according to the actual collapse conditions of the first goaf 101 and the third goaf 301. Since the material and hardness of each rock layer are different, the collapse amount varies. When the collapse amount is large, i.e., when many layers of rock collapse, d and e are set to 7.0m. Simultaneously, the lateral dimensions of the roadway filling body 6 are increased to improve its stability and safety, thereby protecting transport roadway 5 and return airway 4.

[0081] Alternatively, the dimensions of the haulage roadway 5 and the return airway 4 in the left-right direction can be determined based on the length of the second mining face 2. For example, when the length of the second mining face 2 is 200m, the left-right dimensions of the haulage roadway 5 and the return airway 4 are set to 5m; when the length of the second mining face 2 is 300m, the left-right dimensions of the haulage roadway 5 and the return airway 4 are set to 7m.

[0082] This facilitates ventilation in the return airway 4 during mining operations in the second mining face 2, and allows the transport airway 5 to transport coal during mining operations in the second mining face 2.

[0083] The green mining method for coordinating the collapse and filling of adjacent longwall working faces in this embodiment of the invention sets d and e to set the dimensions of the return airway 4 and the transport roadway 5 in the left and right directions. The size of d and e is set according to the collapse conditions on site and the length of the second mining working face 2, thereby improving the efficiency and safety of coal mining in the second mining working face 2.

[0084] In some embodiments, the first mining face 1, the second mining face 2, and the third mining face 3 all adopt a retreat mining method, excavating the transport roadway 5 and the return air roadway 4 in advance, filling the roadway filling body 6 in the return air roadway 4 and the transport roadway 5, and then starting the mining of the first mining face 1, the second mining face 2, and the third mining face 3.

[0085] Specifically, the first mining face 1, the second mining face 2, and the third mining face 3 are all mined from the front end of the mining area 40 to the rear end, that is, from the end of the mining area 40 away from the main haulage roadway 30 to the direction adjacent to the main haulage roadway 30. Before mining, the return airway 4 and the haulage roadway 5 are excavated in advance, supported, and the roadway filling body 6 in the return airway 4 and the haulage roadway 5 is filled, thereby starting the mining of the first mining face 1, the second mining face 2, and the third mining face 3. The first mining face 1 and the third mining face 3 can be mined before the second mining face 2, or the first mining face 1 and the third mining face 3 can be mined simultaneously with the second mining face 2. By excavating the haulage roadway 5 and the return airway 4 in advance, and filling the first roadway filling body 61 and the second roadway filling body 62, the rock strata above the mining area 40 can be supported, improving the stability and safety of coal mining in the mining area 40. Furthermore, the first mining face 1 and the third mining face 3 adopted the caving method to treat the goaf, while the second mining face 2 adopted the filling method to treat the goaf, supporting the rock strata in mining area 40, avoiding ground subsidence while reducing filling costs.

[0086] In some embodiments, when the caving method is used to treat the first mining face 1 and the third mining face 3, as coal mining progresses, the rock strata above the goaf fracture and collapse. However, there is always a stable rock stratum, and regardless of the advancing distance, the fracture height of the rock stratum in the vertical direction no longer increases.

[0087] The rock strata above the goaf fractured and collapsed with a fracture angle. The coal mine roof fractured in the shape of a trapezoidal platform. The base angle of the trapezoidal platform is set as the rock strata fracture angle. The rock strata are numbered sequentially upwards from the coal seam, with the rock strata numbered i=1, 2, ... ,j,..., , ,

[0088] ,

[0089] in, This represents the ultimate fracture length of the rock strata unaffected by boundaries, and indicates the minimum span of the rock strata. For the tensile strength of the rock strata, To bear the load for the (n+1)th rock layer. To stabilize the thickness of the rock strata in the vertical direction,

[0090] ,in The span in the direction of the coal mining face. h represents the thickness of the rock strata, with the subscript indicating the stratigraphic position. i This indicates the thickness of the corresponding rock stratum, where n is the number of the highest rock stratum where the fracture occurred. The height of the trapezoidal truncated cone.

[0091] Let the length of the first mining face 1 be a, and the length of the third mining face 3 be b, where a and b satisfy: a = b < And 50m≤a=b≤80m.

[0092] Specifically, such as Figures 1 to 6 As shown, when using the caving method to treat the first mining face 1 and the third mining face 3, as coal mining progresses, the rock strata above the goaf fracture and collapse. However, there is always a stable rock stratum. Regardless of the advancing distance, the fracture height of the rock stratum in the vertical direction no longer increases. That is, there is always a layer of rock that no longer fractures and collapses, regardless of the distance between the advances of the first mining face 1 and the third mining face 3.

[0093] The rock strata above the goaf fractured and collapsed with a fracture angle, specifically, after the rock strata above the first goaf 101 and the second goaf 201 fractured and collapsed, a fracture angle was formed, as shown in the figure. The longitudinal section of the collapsed rock fault in the front-to-back direction is trapezoidal, and the rock strata fracture angle is... This refers to the base angle of the trapezoid. The rock strata are numbered sequentially upwards from the coal seam, i=1, 2, ... ,j,..., , Where i is the rock stratum number, and when i=j, it can be understood as h j This refers to the thickness of the roof directly above mining area 40.

[0094] This refers to the thickness of the fractured rock strata above the mining area in the vertical direction.

[0095] This represents the ultimate fracture length of a rock stratum unaffected by its boundaries, indicating the minimum span of the rock stratum, which is the dimension of the unfractured rock stratum in the lateral direction. The tensile strength of the rock strata was determined by sampling and testing in the on-site construction laboratory. The load-bearing capacity of the (n+1)th rock layer is specifically determined by on-site construction laboratory sampling and testing.

[0096] For example, during mine construction, boreholes are drilled to sample the rock strata, and the rock strata above the coal mining face are numbered.

[0097] Tests will be conducted based on the specific mining location. For the tensile strength of rock strata and To bear the load for the (n+1)th rock layer, it can and The rock stratum with the largest ratio is set as a stable rock stratum, thereby predicting the approximate location of the non-fractured rock strata after the actual collapse.

[0098] It is understandable that the adoption and In the comparison, the three largest values ​​and their corresponding rock strata were selected for calculation. To obtain W n+1 , and then calculate Given a and b, and 50m≤a=b≤80m, the face length range of the first mining face 1 and the third mining face 3 is determined. Then, the workers determine the face length of the first mining face 1 and the third mining face 3 based on the actual coal cutting length of the coal mining machine in the left and right directions.

[0099] The span of the coal mining face for which the roof is treated using the caving method is the face length of the first mining face 1 and the third mining face 3.

[0100] Furthermore, after the second mining face 2 has been mined a predetermined distance, the goaf of the second mining face 2 will be backfilled. This will prevent the goaf of the second mining face 2 from collapsing and improve the stability and safety of on-site coal mining.

[0101] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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, they should not be construed as limitations on this invention.

[0102] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0103] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0104] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0105] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0106] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A green mining method for coordinating caving and backfilling in adjacent longwall working faces, characterized in that, include: The mining face of the mining area is divided into a first mining face, a second mining face, and a third mining face along the width direction. The length of the second mining face is greater than the length of the first mining face and the length of the third mining face. The first and third mining faces used the caving method to treat the goaf, while the second mining face used the filling method to treat the goaf. The length of the second mining face is c, and c satisfies 450m≥c≥200m. Let the dimension of the transport roadway in the width direction of the mining face be d, and let the dimension of the return air roadway in the width direction of the mining face be e. Then d and e satisfy: 5m≤d=e≤7m. When using the caving method to deal with the first and third mining faces, as coal mining progresses, the rock strata above the goaf fracture and collapse. However, there is always a stable rock stratum, and regardless of the advancing distance, the fracture height of the rock stratum in the vertical direction no longer increases. The rock strata above the goaf fractured and collapsed with a fracture angle. The coal mine roof fractured in the shape of a trapezoidal platform. The base angle of the trapezoidal platform is set as the rock strata fracture angle. The rock strata are numbered sequentially upwards from the coal seam, with the stratum number set as i, where i is 1, 2, etc. ,j,..., , , ， in, This represents the ultimate fracture length of the rock strata unaffected by boundaries, and indicates the minimum span of the rock strata. For the tensile strength of the rock strata, To bear the load for the (n+1)th rock layer. To stabilize the thickness of the rock strata in the vertical direction, ,in The span in the direction of the coal mining face. The value represents the thickness of the rock strata, and the subscript indicates the number of rock strata. Number the highest rock stratum where the fracture occurred. The height of the trapezoidal truncated cone. The span of rock strata is such that the rock strata strength is just sufficient to prevent fracture. Let the length of the first mining face be 'a', and the length of the third mining face be 'b', where a and b satisfy: a = b < And 50m≤a=b≤80m.

2. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 1, characterized in that, The mining area is provided with a return airway and a transport airway. The return airway is located between the first mining face and the second mining face and is connected to the main return airway. The transport airway is located between the second mining face and the third mining face and is connected to the main transport airway. The return airway is arranged when the first mining face is being mined and the transport airway is arranged when the third mining face is being mined. The return airway and the transport airway are supported.

3. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 2, characterized in that, Support is provided for the return airway and transport airway. Roadway filling bodies are set up in the transport airway and return airway. Surface filling stations and underground filling stations are set up to fill the roadway filling bodies. The roadway filling bodies isolate the goaf of the second mining face from the transport airway or return airway.

4. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 3, characterized in that, The second mining face was filled using both surface filling stations and underground filling stations.

5. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 2, characterized in that, The first, second, and third mining faces all employ an advance mining method. The first and third mining faces are mined before the second mining face. When the first mining face is mined, a return airway is arranged and roadway support is provided. When the third mining face is mined, a transport roadway is arranged and roadway support is provided. The roadway filling materials in the transport roadway and return airway are filled. When the second mining face is mined, the goaf of the second mining face is filled.

6. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 5, characterized in that, The distance between the coal mining sites of the first and second mining faces in the direction of the mining area extension is A, and 100m ≤ A ≤ 200m. The distance between the coal mining area of ​​the third mining face and the coal mining area of ​​the second mining face in the direction of the mining area extension is B, and 100m≤B≤200m.

7. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 2, characterized in that, Both the first and third mining faces adopt the forward mining method, while the second mining face adopts the backward mining method. When mining the first mining face, a return airway is arranged, roadway support is provided, and the roadway filling material in the return airway is filled. When mining the third mining face, a transport roadway is arranged, roadway support is provided, and the roadway filling material in the transport roadway is filled.

8. The green mining method for coordinating caving and backfilling of adjacent longwall working faces according to claim 2, characterized in that, The first, second, and third mining faces all employ a retreat mining method, with the transport roadway and return airway advanced in advance. The roadway filling material in the return airway and transport roadway is then filled before mining begins on the first, second, and third mining faces.

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