Mining and filling method and equipment of full-negative-pressure continuous mining machine for leftover coal

Abstract

The invention discloses a mining and filling method and equipment of a full-negative-pressure continuous mining machine for leftover coal, and belongs to the technical field of coal mining. The mining and filling method comprises the steps of stoping unit arrangement, block mining chamber stoping, block goaf filling, mining and filling of the whole set of stoping units and mining and filling of all edge coal, the length of the mining chamber can exceed the length of a continuous mining machine body by 10-50 m, and the moving and reversing frequency of a working face is effectively reduced; the mining and filling equipment comprises a continuous mining machine, a mining support, a filling support, a wind barrier and a detachable retaining wall, the filling support is additionally provided with a tail isolation device and has the advantages of being easy to assemble and good in isolation effect, and the wind barrier can guarantee ventilation safety when full-negative-pressure wind flows through a mining cave; the mining efficiency and the filling effect of the working face are effectively improved, and then the resource recovery rate and the coal yield of a mine are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mining, and specifically relates to a mining and filling method and equipment for a full negative pressure continuous mining machine for corner coal. Background Art

[0002] Mines often use shortwall mining, tunnel mining, and continuous mining (such as Wangwili mining) to recover corner coal. Various methods have played a certain role in improving the overall resource recovery rate of coal mines. Since the corner coal area is small and irregular, its recovery face (i.e., working face) is mostly a short wall face, and it is difficult to form full negative pressure ventilation in longwall mining. Therefore, most of the recovery faces in the existing corner coal mining methods still use local ventilators for ventilation. Compared with the longwall mining method, a large number of coal pillars need to be left when mining corner coal, and the recovery rate is low. The recovery rate of the existing corner coal mining methods is mostly between 30% and 50%. A few mines combine the filling process with the corner coal continuous mining machine, making full use of the filling body to replace the coal pillar to support the roof and the rapid excavation function of the continuous miner, which reduces the loss of coal pillars to a certain extent. However, due to the problems of ventilation safety and the matching of mining and filling equipment, there are few successful cases of filling mining of corner coal continuous miners.

[0003] The Coal Mine Safety Regulations (2016 Edition) first regulated continuous mining, and the current Coal Mine Safety Regulations (2022 Edition) still uses these regulations, two of which are: "The continuous mining face must be ventilated with full wind pressure before mining can begin", and "The maximum cutting depth of the continuous miner should be reasonably determined based on factors such as roof conditions, equipment support, and coal mining technology". After the 2016 Edition of the Regulations was implemented, the previous mining method of using local ventilators for ventilation on the mining face was eliminated. It is understood that the current filling mining technology of corner coal continuous miners has almost always been in the technical research stage or trial mining stage.

[0004] CN 113944464 A discloses "a method for mining corner coal with full negative pressure continuous mining machine", which adopts the "one in and one out" ventilation mode to arrange the tunnels, and realizes full negative pressure ventilation in the mining unit branch tunnels and the mining chamber (i.e., the mining face). Although this patented technology meets the full wind pressure ventilation regulations in the "Coal Mine Safety Regulations", the maximum length of the mining chamber (i.e., the maximum cutting depth of the continuous mining machine in the mining face) is the length of the continuous mining machine body. When the length of the mining face exceeds the length of the continuous mining machine body, it can only rely on diffusion ventilation or local ventilation fans, and full negative pressure ventilation cannot be achieved; the short length of the mining chamber will lead to frequent relocation and reversal of the working face, affecting the production progress and low coal production. Secondly, in this patented technology, fresh air flows past the continuous miner and the mining shaft during mining. When the stability of the coal seam roof is poor, the air flow may flow through the roof collapse area next to the mining shaft. This violates the provisions of the "Coal Mine Safety Regulations" that "the air intake and return air of the mining face shall not pass through the roof collapse area". When the coal seam gas concentration is high, it may also cause safety accidents.

[0005] CN 115839240 A discloses "a method for continuous mining of corner coal in high-gas mines", which adopts a "one-in, two-out" ventilation method to arrange the tunnels, and uses a gas extraction method that mainly exhausts gas with wind and extracts gas from the goaf in parallel to dilute the gas. Full negative pressure ventilation is achieved in the branch tunnels of the mining unit and the mining chamber, and the problem of gas accumulation or over-limit in the continuous mining working face is solved. However, like the patent CN 113944464 A, the maximum length of the mining chamber in this patent technology is still the length of the continuous mining machine body, the working face is frequently moved and reversed, and the wind flow may flow through the roof collapse area next to the mining chamber, which violates the relevant provisions of the "Coal Mine Safety Regulations".

[0006] After consulting existing patent documents, academic reports and related books at home and abroad, the problem of short maximum cutting depth in full negative pressure continuous mining face has not been effectively solved; for the problem of wind flow flowing through the roof collapse area, a few projects have combined the filling process with the continuous mining machine mining technology, using the filling body to support the coal seam roof to prevent large-scale collapse of the roof in the goaf area. However, how to reasonably determine the factors such as roof management, cutting depth, and mining and filling equipment matching after continuous mining combined with the filling process is a major technical problem currently faced by many scholars and engineers.

[0007] CN 108825237 A discloses "a layered and divided mining process combining a continuous miner with filling for extra-thick coal", which combines the continuous miner mining and filling processes and applies them to the corner coal of extra-thick coal seams. It has a certain reference role in the in-depth study of the continuous miner filling mining technology, especially the study of roof management after continuous miner mining. However, there are still some problems and shortcomings in this patented technology: first, the upper layer adopts Wangevilli mining, which no longer meets the full wind pressure ventilation regulations in the "Coal Mine Safety Regulations"; secondly, the length of the mining tunnel (i.e., the cutting depth) is limited to the length of the continuous miner body (only 10m), which has the disadvantage of frequent moving and reversing of the working face; thirdly, it simply fills the filling pipeline deep into the goaf of the working face, and does not introduce how the mining and filling equipment is matched, resulting in the inability of this patented technology to guide the construction work on the engineering site.

[0008] CN 104500070 A discloses "a method for continuous coal mining machine paste filling mining", where the continuous mining machine mining and paste filling pipelines are arranged in the branch lanes on both sides of the main and auxiliary lanes, and the parallel mining and filling operations are applied to the "three-down" compressed coal mining. Since the patent application was filed in 2015, the "Coal Mine Safety Regulations" (2016 edition) has not yet been implemented. Now the patent technology has the following problems and shortcomings: first, the continuous mining machine mining is a lane-type left-right mining (similar to the Wangeville type), which is ventilated by local ventilators and does not meet the full wind pressure ventilation regulations in the "Coal Mine Safety Regulations"; secondly, the length of the mining tunnel is 11m, and there is a problem of frequent moving and reversing of the working face; thirdly, the mining and filling operations are arranged on both sides of the main and auxiliary lanes, and the two systems are carried out independently, and the supporting technology of the mining and filling equipment is not mentioned.

[0009] CN 111535844 A discloses "coal pillar-free mining equipment system and method for hard roof along goaf-retaining lanes", which sets a combined support consisting of a base, a top beam, a support, a filling baffle and a fixed plate, and performs filling operations in the goaf-retaining area on one side of the goaf while performing coal mining operations in the coal mining channel. Since coal pillar-free mining along goaf-retaining lanes belongs to a type of longwall mining system, it is necessary to densely distribute a number of combined supports on the working face to support the working face roof and push the working face mining and transportation equipment. However, in the continuous mining machine filling mining technology, only a few supports are needed to support the working face roof, and there is no need to push the mining and transportation equipment. Therefore, the mining equipment system and method disclosed in this patent technology are not suitable for the continuous mining machine filling mining process. Summary of the invention

[0010] The present invention overcomes the shortcomings of the prior art and proposes a mining and filling method and equipment for a full-negative pressure continuous miner of marginal coal; it solves the problems in the current filling mining technology of the continuous miner of marginal coal, such as the short length of the mining tunnel, the inability to ensure ventilation safety when the wind flows past the deep mining tunnel, the unreasonable matching of the mining and filling equipment, and the low resource recovery rate and coal output.

[0011] The present invention is achieved through the following technical solutions: A method for mining and filling a corner coal full negative pressure continuous mining machine comprises the following steps: Step 1: Arrange the mining unit: the mining unit includes the mining branch tunnel, the filling branch tunnel and the internal coal pillars between them; the internal coal pillars are divided into multiple blocks, each block includes multiple deep mining chambers; isolation coal pillars and unit cross-sections are set between adjacent blocks, and temporary closed walls are set in the unit cross-sections; Step 2: Mining the innermost block: first, set up mining supports and filling supports in front of the two end branch tunnels of the innermost deep mining cave in the innermost block, and then use a continuous miner to mine the innermost deep mining cave. After mining, move the mining supports and filling supports to the two end branch tunnels of the innermost deep mining cave, and hang wind barriers between the mining supports and filling supports, and then mine the next adjacent deep mining cave. In this way, retreat mining in sequence until the last deep mining cave in the innermost block is mined; Step 3, filling the goaf of the innermost block: after the last deep mining chamber in the innermost block is mined, the wind barrier is removed, and the mining support and the filling support are respectively moved to the branch tunnel openings at both ends of the isolation coal pillar between the innermost block and the next block, and then the temporary closed wall in the unit cross-section between the two blocks is opened to form a ventilation system between the mining unit branch tunnel and the next block; then a detachable retaining wall is set at the isolation coal pillar position in the mining branch tunnel, and at the same time, the tail isolation device of the filling support is started in the filling branch tunnel to block the goaf of the innermost block; then the goaf is filled; Step 4: Mining and filling the entire mining unit: Mining and filling the remaining blocks in the mining unit from the inside to the outside in accordance with steps 2 and 3, until all the blocks in the entire mining unit are mined and filled; Step 5: Mining and filling all the corner coal: According to steps 2 to 4, adjacent mining units are mined and filled from the inside to the outside and alternately from left to right until all the corner coal areas are mined and filled.

[0012] Preferably, the length of the deep mining shaft is 10m to 50m.

[0013] Preferably, the width of the deep mining chamber is the mining width of the continuous miner, and the width of each block is 4 to 6 mining chamber widths; the width of the isolation coal pillar is 1 to 2 mining chamber widths, and the transverse width of the unit is 1 mining chamber width.

[0014] Preferably, the filling of the goaf in step three is to extend the filling pipe into the goaf along the top plate of the filling branch tunnel through the filling hole reserved at the upper end of the tail isolation device of the filling support, open the gate valve on the filling pipe for filling, until the filling body fills the goaf of the innermost block.

[0015] Preferably, in step three, the detachable retaining wall is inserted into the surrounding rock of the mining branch tunnel on all sides, and an isolation membrane is closely attached to the goaf side of the detachable retaining wall to seal the mining branch tunnel.

[0016] The mining and filling equipment used for the described method of full-negative-pressure continuous miner mining and filling of corner coal includes a continuous miner, a mining support, a filling support, a wind barrier and a detachable retaining wall; the mining support is arranged in the mining branch tunnel at one end of the deep mining tunnel immediately following the continuous miner, and the filling support is arranged in the filling branch tunnel at the other end of the deep mining tunnel; during mining, the wind barrier is hung between the mining support and the filling support across the goaf; during filling, the filling support and the detachable retaining wall are arranged in the branch tunnels at both ends of the isolation coal pillar to seal the goaf of the entire block.

[0017] Furthermore, the filling bracket includes a bracket body and a tail isolation device arranged on the bracket body; the bracket body includes a top beam, a base and a pillar; the tail isolation device includes a tail beam, a tail seat, an isolation plate, an inclined pillar and a film roller; the tail of the top beam is connected to the tail beam, and the tail of the base is connected to the tail seat, and the tail beam and the tail seat are still supported by the pillars; the tail of the tail seat is connected to the isolation plate, and the inclined pillar is connected between the base and the isolation plate, and a film roller is suspended under the tail of the top beam, and an isolation film is installed on the film roller.

[0018] Furthermore, the isolation plate is a combined plate that can be combined and spliced ​​upward and left and right; when the filling support is used to seal the goaf, the membrane roller is first rotated to pull the isolation membrane to the bottom plate of the goaf side branch tunnel of the isolation plate, and then the isolation plates are combined and spliced ​​to close the filling branch tunnel.

[0019] The beneficial effects of the present invention compared with the prior art are as follows: (1) The mining and filling method provided by the present invention breaks through the technical bottleneck of the existing continuous mining technology that the maximum cutting depth (i.e., the length of the mining tunnel) during mining does not exceed the length of the continuous mining machine body. The length of the deep mining tunnel can reach 10m to 50m. After the length of the mining tunnel is increased, it can not only ensure full negative pressure ventilation of the working face, but also avoid safety problems such as roof collapse. At the same time, it can reduce the frequency of moving and falling of the working face, promote production progress, and thus increase coal production. Taking mining safety into consideration, the present invention limits the length of the deep mining tunnel to 10m to 50m. Under the premise that the coal seam roof is stable, the filling body is strong enough, and the coal pillars are sufficient, the maximum length of the mining tunnel can be even greater.

[0020] (2) The mining and filling method and equipment provided by the present invention innovatively introduce wind barriers into the full negative pressure air path of the continuous mining machine. The wind barriers are reasonably hung in the goaf area of ​​the previous mining cave of the positive recovery deep mining cave, and full negative pressure ventilation of the working face can be achieved during the deep mining cave. Since the wind barrier is close to the positive recovery deep mining cave (the distance is usually less than the maximum control top distance), although it is located in the goaf area, the roof of the goaf area where the wind barrier is located will not collapse in a short time. Therefore, the wind barrier can smoothly guide the full negative pressure airflow in the deep mining cave, improve the ventilation efficiency, and avoid the airflow from flowing through the roof collapse area, meeting the relevant provisions of the "Coal Mine Safety Regulations". At the same time, the wind barrier can also isolate the gas and toxic and harmful gases in the goaf area on the other side of the wind barrier, effectively solving the ventilation safety problem of full negative pressure airflow passing by the deep mining cave.

[0021] (3) The mining and filling method and equipment provided by the present invention innovatively integrate the filling support and the detachable retaining wall into the continuous mining process. During mining and filling, each device performs its own function and cooperates closely, which effectively improves the recovery efficiency and filling effect of the working face. The mining support is arranged in the mining branch tunnel at one end of the deep mining shaft right after the continuous miner. It is responsible for supporting the roof of the branch tunnel behind the mining shaft, which can not only ensure the stability of the roof caused by mining at the rear of the mining shaft, but also ensure the safety of personnel operating the continuous miner and ancillary equipment under the mining support; the filling support is arranged in the filling branch tunnel at the other end of the deep mining shaft, which can not only assist the mining support in jointly supporting the roof of the branch tunnels at both ends of the deep mining shaft, but also ensure the safety of personnel operating the filling device under the filling support during filling; during mining, the wind barrier is hung between the mining support and the filling support across the goaf, which can effectively guide the wind flow during mining in the deep mining shaft; during filling, the filling support and the detachable retaining wall are arranged in the branch tunnels at both ends of the isolation coal pillar, which can effectively seal the goaf of the entire block to prevent leakage and slurry running during the filling process. At the same time, the filling support and the detachable retaining wall can be reused, reducing the cost of goaf sealing materials.

[0022] (4) The mining and filling method provided by the present invention divides each group of mining units into multiple blocks, and performs mining and filling operations from the inside to the outside. During operation, the filling body, isolation coal pillars, inter-unit coal pillars, mining supports, filling supports, and support materials across the top of the branch tunnel are used to jointly support the roof of the coal seam in the block, which is conducive to the roof management of the goaf area after deep mining, and avoids large-scale collapse of the roof in the goaf area of ​​the block, as well as safety problems such as roof pressure and gas influx caused by roof collapse. Compared with the existing full negative pressure continuous mining machine mining technology, the addition of filling bodies and filling supports can reduce the size of isolation coal pillars and inter-unit coal pillars, thereby improving the resource recovery rate of the working face, which can reach 50% to 70%.

[0023] (5) The mining and filling equipment provided by the present invention also innovatively proposes a new type of filling support, which is modified by adding a tail isolation device to the ordinary support body. It takes into account the supporting ability of the ordinary support for the coal seam roof and the sealing ability of the isolation device for the filling area. It has the characteristics of simple assembly, low investment and good isolation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the plan layout of the mining and filling method of the full negative pressure continuous mining machine for corner coal according to the present invention; Figure 2 This is a schematic diagram of the mining arrangement of block ① in the mining unit of the present invention; Figure 3 It is a schematic diagram of the filling arrangement of the goaf area in block ① of the mining unit according to the present invention; Figure 4 This is a schematic diagram of the modified structure of the filling bracket according to the present invention; In the figure: 1—transport chute; 2—return air chute; 3—mining branch tunnel; 4—filling branch tunnel; 5—coal pillars between units; 6—adjusting air door; 7—enclosed wall; 8—deep mining cavern; 9—isolation coal pillars; 10—unit cross-section; 11—temporary closed wall; 12—goaf; 13—new air flow; 14—lack of air flow; 15—mining support; 16—filling support; 161—tail beam; 162—tail seat; 163—isolation board; 164—inclined support; 165—membrane roller; 166—top beam; 167—base; 168—support; 17—continuous miner; 18—wind barrier; 19—detachable retaining wall; 20—isolation membrane; 21—filling pipe; 22—filling body. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail in conjunction with the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. The technical solutions of the present invention are described in detail below in conjunction with the embodiments and the accompanying drawings, but the scope of protection is not limited thereto.

[0026] like Figures 1 to 3 As shown, this embodiment provides a method for mining and filling corner coal with a full negative pressure continuous mining machine, comprising the following five steps: Step 1: Layout of mining units: Figure 1As shown, two drift tunnels, a transport drift 1 and a return wind drift 2, are arranged along the corner coal area, and then multiple groups of mining units are arranged in sequence from the inside to the outside along both sides of the drift tunnel (a group of mining units on the right side of the drift tunnel is taken as an example in this embodiment), and a group of mining units consists of a mining branch tunnel 3, a filling branch tunnel 4 and its internal coal pillars; the interior of the mining unit is divided into multiple blocks such as ①, ②, ③, ..., each block has 4 to 6 mining tunnels, and each mining tunnel is a deep mining tunnel 8; isolation coal pillars 9 and unit cross-sections 10 are provided between adjacent blocks, and temporary closed walls 11 are provided in the unit cross-sections 10. During on-site construction, the drift tunnel should be arranged as high as possible along the corner coal area, so that the position of the mining unit branch tunnel is relatively low, so as to facilitate the self-flow of the filling body 22 during filling. The two drift tunnels are connected to the two branch tunnels of each mining unit, and adjustable dampers 6 and closed walls 7 are reasonably set at the intersections to form a full negative pressure ventilation system between the drift tunnel and the branch tunnels of each mining unit.

[0027] Furthermore, in step 1, the length of the deep mining cave 8 is 10m to 50m, and the width of the deep mining cave 8 is the mining width of the continuous mining machine 17. During on-site construction, the angle between the chute roadway and the mining unit branch roadway is 50° to 70°, and the angle between the deep mining cave 8 and the mining branch roadway 3 is 40° to 60°. The two mining unit branch roads may not be arranged in parallel, but the angle between the branch roadway and the chute roadway should be in the range of 50° to 70°, and the net width of the coal pillar inside the mining unit shall not be greater than the cosine value of the angle between the deep mining cave 8 and the mining branch roadway 3 multiplied by the maximum length of the deep mining cave 8; the width of the deep mining cave 8 should be reasonably determined according to the specifications of the continuous mining machine 17, which is the width of one cut of the continuous mining machine 17.

[0028] Furthermore, in step one, the width of each block is 4 to 6 mining tunnels, the width of the isolation coal pillar 9 is 1 to 2 mining tunnels, and the width of the unit cross section 10 is 1 mining tunnel; an inter-unit coal pillar 5 is provided between two adjacent groups of mining units, and the width of the inter-unit coal pillar 5 is 10m to 15m. During on-site construction, when dividing the internal blocks of the mining unit, the width of each block should be reasonably determined based on factors such as the width of the isolation coal pillar 9 and the inter-unit coal pillar 5, the length of the mining tunnels within the block, the support strength of the mining unit branch tunnels and the top of the unit cross section 10. It is usually appropriate to take 4 to 6 mining tunnels. If the width is too small, there will be too many block divisions and frequent alternation of mining and filling processes. If the width is too large, it will make it difficult to manage the roof of the goaf after the mining of the mining tunnels in the block. The main function of the isolation coal pillar 9 is to effectively control the internal blocks. Effective plugging, its width should be reasonably determined according to factors such as coal seam thickness (specifically, mining height of the mining tunnel), coal seam stability and density. In the project, when encountering medium-thick coal seams with good stability and density, the isolation coal pillar 9 takes 1 mining tunnel width, and when encountering poor stability and density or thick coal seams, it takes 2 mining tunnel widths; the main function of the unit cross 10 is to ensure the formation of a ventilation system during mining in each block, and it does not need to be too wide. When arranging the branch tunnels of the mining unit, it can be dug in advance with a continuous mining machine 17, that is, the width of the unit cross 10 takes 1 mining tunnel width. If the coal seam roof has structural or other special geological conditions and the mine pressure is serious at the project site, the size of the inter-unit coal pillar 5 and the isolation coal pillar 9 should be increased to ensure the safety of the project construction.

[0029] Step 2: Mining and recovery of block ①: Figure 2 As shown, mining supports 15 and filling supports 16 are first set in front of the two end branch tunnels of the innermost deep mining shaft 8 in block ①, and then the continuous mining machine 17 is used to mine the innermost deep mining shaft 8; after the innermost deep mining shaft 8 is mined, the mining supports 15 and filling supports 16 are respectively moved to the two end branch tunnels of the innermost deep mining shaft 8, and wind barriers 18 are hung between the mining supports 15 and the filling supports 16, and then the next connected deep mining shaft 8 is mined; in this way, backward mining is carried out in sequence until the last deep mining shaft 8 in block ① is mined. During on-site construction, the number of mining supports 15 and filling supports 16 should be reasonably determined based on factors such as roof pressure and branch tunnel width, and usually should not be less than two. During mining, the distance between the front end of the mining supports 15 and filling supports 16 and the empty wall of the deep mining shaft 8 being mined is 1m to 2m; the mining support 15 is used in conjunction with the continuous mining machine 17, which is responsible for supporting the branch tunnel roof behind the deep mining shaft 8 being mined, and the filling support 16 is mainly used in conjunction with the filling pipe 21, and assists the mining support 15 in jointly supporting the branch tunnel roof at both ends of the deep mining shaft 8; the wind barrier 18 is hung above the nearest mining support 15 and filling support 16 at both ends of the deep mining shaft 8, and crosses the goaf of the previous deep mining shaft 8 of the deep mining shaft 8 being mined, and is responsible for guiding the full negative pressure airflow in the deep mining shaft 8; see Figure 2The new air flow 13 flows from the mining branch tunnel 3 to the area between the deep mining chamber 8 and the wind barrier 18, forming the exhausted air flow 14 and then flowing to the filling branch tunnel 4.

[0030] Step 3: Filling of the mined-out area in Block ①: Figure 3 and Figure 4 As shown, after the last deep mining cavern 8 in block ① is mined, the wind barrier 18 is removed, and the mining support 15 and the filling support 16 are moved to the branch tunnels at both ends of the isolation coal pillar 9 between blocks ① and ②, and then the temporary closed wall 11 in the innermost unit cross section 10 of block ② is opened to form a ventilation system for the mining unit branch tunnel and block ②, see Figure 3 , the new air flow 13 passes through the unit crossbar 10 to form the exhausted air flow 14 and then flows to the filling branch tunnel 4; then a removable retaining wall 19 is set at the position of the isolation coal pillar 9 in the mining branch tunnel 3, and at the same time, the tail isolation device of the filling support 16 is started in the filling branch tunnel 4 to block the goaf 12 of block ①; then the filling pipe 21 is extended into the goaf 12 along the top plate of the filling branch tunnel 4 through the filling hole reserved at the upper end of the isolation plate 163, and the gate valve on the filling pipe 21 is opened for filling until the filling body 22 fills the goaf of block ①. During on-site construction, before sealing the goaf 12 of a block, the temporary closed wall 11 in the unit cross-section 10 between the next connected block should be opened first to form a ventilation system between the mining unit branch tunnel and the next connected block before sealing the goaf 12 of the block; when setting up the removable retaining wall 19 and starting the tail isolation device, the staff should operate within 6m of the ventilation system line to meet the requirements of diffuse ventilation. At the same time, gas monitoring at the location of the personnel should be strengthened to prevent poisoning and suffocation of the personnel; in order to meet the filling needs of the filling pipe 21, the filling pipe 21 in the filling branch tunnel 4 should be reasonably equipped with a series of supporting regulating valves, stop valves, material distribution valves, reducers and other components. After filling each block, the filling pipe 21 should be cleaned as necessary.

[0031] Furthermore, in step 3, the detachable retaining wall 19 should be inserted into the surrounding rock of the mining branch tunnel 3, and the mining side of the detachable retaining wall 19 is closely attached with an isolation membrane 20 to seal the mining branch tunnel 3. During on-site construction, the detachable retaining wall 19 can be assembled by itself or purchased as a finished product on the market, as long as it meets the effective blocking and disassembly functions of the mining branch tunnel 3; the isolation plate 163 of the filling support 16 and the mining side of the detachable retaining wall 19 are closely attached with a layer of isolation membrane 20, and the isolation membrane 20 needs to seal the entire branch tunnel section. When one layer cannot seal the entire branch tunnel section, multiple layers can be overlapped.

[0032] Step 4: mining and filling of the entire mining unit: after the filling body 22 in block ① is basically solidified, remove the removable retaining wall 19, and retract the tail isolation device of the filling support 16, then move the mining support 15 and the filling support 16 to the branch tunnels at both ends of the innermost unit traverse 10 in block ② respectively, and hang the wind barrier 18 in the same way as step 2, and retreat the deep mining caves 8 in block ② in sequence, until the last deep mining cave 8 in block ② is mined; leave an isolation coal pillar 9 and open the temporary closed wall 11 in the innermost unit traverse 10 of block ③, after forming a ventilation system between the mining unit branch tunnel and block ③, fill the goaf of block ② in the same way as step 3; in this way, the remaining blocks in the mining unit are mined and filled in turn from the inside to the outside in the same way as steps 2 and 3, until all the blocks in the entire mining unit are mined and filled. During on-site construction, the removable retaining wall 19 can be removed and the tail isolation device can be retracted only after the solidification strength of the filling body 22 in the block reaches 70% of the design strength and is not squeezed, deformed or flowed; after removal and retraction, the isolation membrane 20 is still attached to the filling body 22, and try not to destroy the closed structure of the isolation membrane 20.

[0033] Step 5: Mining and filling all the corner coal: After a group of mining units are mined and filled, the next group of mining unit branch tunnels are arranged from the inside to the outside and alternately from left to right. The adjacent mining units are mined and filled in turn in the same way as steps 2 to 4, and this is done until all the corner coal areas are mined and filled. During on-site construction, when all mining units are mined and filled, on the premise of ensuring roof safety and ventilation safety, the two chute tunnels can be compared to the mining unit branch tunnels, and the two chute tunnels and their internal coal pillars can be reasonably mined and filled in a similar way to steps 2 to 4 to further improve the recovery rate of corner coal resources.

[0034] Furthermore, the tops of the drift tunnel, mining branch tunnel 3, filling branch tunnel 4, and unit cross section 10 are all provided with supporting materials to stabilize the coal seam roof, and no supporting materials are required on the tops of the deep mining chambers 8 inside each mining unit. During on-site construction, the supporting materials on both sides of the aforementioned tunnels should be reasonably determined based on factors such as roof pressure, mining height, and coal seam stability. Under the premise of ensuring the safety of tunnel construction, the mining sides (i.e., the side of the mining chamber arranged inside the mining unit) of the mining branch tunnel 3 and the filling branch tunnel 4, as well as the two sides of the unit cross section 10 should not be provided with supporting materials other than the protective net as much as possible to improve the mining progress.

[0035] Based on the aforementioned method for mining and filling of a full negative pressure continuous miner for corner coal, this embodiment further provides a mining and filling equipment for a full negative pressure continuous miner for corner coal, including a continuous miner 17, a mining support 15, a filling support 16, a wind barrier 18, and a detachable retaining wall 19; the filling support 16 and the detachable retaining wall 19 are matched to the continuous miner mining, and each device performs its own function and cooperates closely during mining and filling, which effectively improves the recovery efficiency and filling effect of the working face. The filling support 16 is modified by adding a tail isolation device to the ordinary support body, taking into account the support capacity of the ordinary support for the coal seam roof and the sealing capacity of the isolation device for the filling area, and has the characteristics of simple assembly, low investment, and good isolation effect.

[0036] During on-site construction, the mining support 15 is arranged in the mining branch tunnel 3 at one end of the deep mining shaft 8, following the continuous mining machine 17, and is responsible for supporting the roof of the branch tunnel behind the mining shaft, which can not only ensure the stability of the roof caused by mining at the rear of the mining shaft, but also ensure the safety of personnel operating the continuous mining machine 17 and its ancillary equipment under the mining support 15; the filling support 16 is arranged in the filling branch tunnel 4 at the other end of the deep mining shaft 8, which can not only assist the mining support 15 in jointly supporting the roof of the branch tunnels at both ends of the deep mining shaft 8, but also ensure the safety of personnel operating under the filling support 16 during filling. Control the safety of the filling pipe 21 and supporting equipment; during mining, the wind barrier 18 crosses the goaf 12 after the deep mining shaft 8 is mined and is hung between the mining support 15 and the filling support 16, which can effectively guide the wind flow during the deep mining shaft mining; during filling, the filling support 16 and the removable retaining wall 19 are set in the branch tunnels at both ends of the isolation coal pillar 9 to block the goaf 12 of the entire block to prevent leakage and slurry running during the filling process. At the same time, the filling support 16 and the removable retaining wall 19 can be reused, reducing the cost of goaf plugging materials. It should be noted that in addition to the aforementioned mining and filling equipment, the project site should also include other necessary supporting equipment such as transportation, support, loading and unloading.

[0037] Further, such as Figure 4As shown, the filling support 16 includes a common support body and a tail isolation device arranged on the support body; the support body includes a top beam 166, a base 167 and a support 168; the tail isolation device of the filling support 16 includes a tail beam 161, a tail seat 162, an isolation plate 163, an inclined support 164, and a film roller 165. When the modification is performed, the tail beam 161 is installed at the tail of the common support top beam 166, and the tail seat 162 is installed at the tail of the base 167. The tail beam 161 and the tail seat 162 are still supported by the support 168. The tail of the tail seat 162 is provided with an isolation plate 163, and the isolation plate 164 is provided with a film roller 165. One side of 63 is hinged to the tail of the tailstock 162; the isolation plate 163 is a combined plate that can be combined and spliced ​​upward and left and right, and a film roller 165 is suspended below the tail of the top beam 166, and an isolation film 20 is installed on the film roller 165; when the filling bracket 16 blocks the goaf, first rotate the film roller 165 to pull the isolation film 20 to the bottom plate of the goaf side branch tunnel of the isolation plate 163, and then rotate the isolation plate 163 to an upright state, and then connect the inclined support 164 between the tail of the base 167 and the isolation plate 163, support and fix the isolation plate 163, and close the filling branch tunnel 4 through the isolation plate 163. During on-site reconstruction, the widths of the tail beam 161 and the top beam 166 need to match, and they are connected by bearings; the widths of the tail seat 162 and the base 167 need to match, and they are connected by bearings; the isolation plate 163 is a composite plate composed of multiple plates spliced ​​together, and the plates are extended or retracted by cableways. A filling hole needs to be reserved at the upper end of the isolation plate 163, and the hole diameter needs to match the filling pipe 21; the two ends of the inclined support 164 are connected to the base 167 and the isolation plate 163 by bearings.

[0038] The mining method and equipment proposed in this embodiment are applied to the filling mining of the corner coal in a certain mine. The average thickness of the coal seam in the corner coal area of ​​the mine is 4.2m, the average burial depth is 240m, and the coal seam roof is limestone with good stability. The specifications and models of the main mining equipment used are as follows: the continuous mining machine 17 adopts the EML340 continuous coal mining machine, with an overall size of 11m×3.3m×2.05m, a mining height range of 2.7 to 5.5m, and a mining width of 3.3m; the mining support 15 adopts 2 XZ7000 / 24.5 / 46 crawler hydraulic supports, and the filling support 16 adopts the two existing ZY6000 / 22 / 45 hydraulic supports of the mine party with the tail isolation device added, and the wind barrier 18 adopts a canvas wind barrier with a width of 4m, and the detachable retaining wall 19 is welded with steel plates and channel steels, and the maximum plugging size after extension is 5.5m×5.0m.

[0039] The corresponding layout parameters in the adopted mining and filling method are as follows: the cross-sectional dimensions of the transport drift 1 and the return air drift 2 are both 4.5m×3.5m, and the top and two sides are supported by anchor mesh; the cross-sectional dimensions of the mining branch roadway 3 and the filling branch roadway 4 are both 4.8m×4.2m, and the top and non-mining sides are supported by anchor rods + metal mesh, and the mining side is supported by metal mesh; the angle between the drift roadway and the mining unit branch roadway is 60°, the net width of the coal pillar inside the mining unit is 30m, and the angle between the deep mining shaft 8 and the mining branch roadway 3 is 45°; the length of the deep mining shaft 8 is 42.4m (equal to 30 / cos45°), The width is 3.3m (equal to the mining width of continuous miner 17), the height is 4.2m (equal to the thickness of the coal seam), and no support materials are set in the deep mining shaft 8; the width of each block inside the mining unit is 16.5m (equal to the width of 5 mining shafts), the width of the isolation coal pillar 9 is 3.3m (the width of 1 mining shaft), and the width of the coal pillar 5 between units is 12m; the width of the unit cross section 10 is 3.3m (the width of 1 mining shaft) and 4.2m (equal to the thickness of the coal seam), the cross section top is supported by anchor rods + metal mesh, and the two sides are supported by metal mesh; the filling method of the goaf is paste filling, and the compressive strength of the filling body after solidification is 4MPa.

[0040] After on-site verification at the mine, the recovery rate of corner coal resources in the working face of the mine is about 65%, the monthly coal production reaches 35,000 tons, and the estimated annual coal production is about 400,000 tons, which exceeds the normal level of the industry (300,000 tons / year). No roof collapse accidents or ventilation safety accidents occurred during mining, and the safety is relatively good. There was basically no leakage or slurry running during filling, and the filling effect was good. The mining and filling method and equipment proposed in this patent have achieved good economic and social benefits for the mine, proving the feasibility and rationality of the technical solution of the present invention.

[0041] Furthermore, the mining and filling method and equipment of the full-negative-pressure continuous miner for corner coal provided by the present invention can replace the continuous miner 17 with an ordinary tunneling machine or coal planer, and the mining and filling method is still applicable; the filling of the goaf is not only suitable for paste filling, but also for slurry filling.

[0042] The above content is a further detailed description of the present invention in combination with a specific preferred embodiment. It cannot be determined that the specific embodiments of the present invention are limited to this. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the present invention, which should be regarded as belonging to the present invention and the scope of patent protection determined by the submitted claims.

Claims

1. A method for mining and filling corner coal with a full negative pressure continuous mining machine, characterized in that: The following steps are involved: Step 1: Arrange the mining unit: the mining unit includes a mining branch tunnel (3), a filling branch tunnel (4) and the internal coal pillars therebetween; the internal coal pillars are divided into a plurality of blocks, each block including a plurality of deep mining chambers (8); an isolation coal pillar (9) and a unit cross section (10) are provided between adjacent blocks, and a temporary closed wall (11) is provided in the unit cross section (10); Step 2, mining and recovery of the innermost block: first, mining supports (15) and filling supports (16) are respectively set in front of the two end branch tunnels of the innermost deep mining cave (8) of the innermost block, and then the innermost deep mining cave (8) is mined by a continuous mining machine (17). After the mining is completed, the mining supports (15) and the filling supports (16) are respectively moved to the two end branch tunnels of the innermost deep mining cave (8), and a wind barrier (18) is hung between the mining supports (15) and the filling supports (16), and then the next adjacent deep mining cave (8) is mined; in this way, the mining is carried out in a backward manner in sequence until the last deep mining cave (8) in the innermost block is mined; Step 3, filling the goaf of the innermost block: after the last deep mining cavern (8) in the innermost block is mined, the wind barrier (18) is removed, and the mining support (15) and the filling support (16) are respectively moved to the branch tunnel openings at both ends of the isolation coal pillar (9) between the innermost block and the next block, and then the temporary closed wall (11) in the unit cross section (10) between the two blocks is opened to form a ventilation system between the mining unit branch tunnel and the next block; then a removable retaining wall (19) is set at the position of the isolation coal pillar (9) in the mining branch tunnel (3), and at the same time, the tail isolation device of the filling support (16) is started in the filling branch tunnel (4) to block the goaf (12) of the innermost block; then the goaf (12) is filled; Step 4: Mining and filling the entire mining unit: Mining and filling the remaining blocks in the mining unit from the inside to the outside in accordance with steps 2 and 3, until all the blocks in the entire mining unit are mined and filled; Step 5: Mining and filling all the corner coal: According to steps 2 to 4, adjacent mining units are mined and filled from the inside to the outside and alternately from left to right until all the corner coal areas are mined and filled.

2. A method for mining and filling corner coal with a full negative pressure continuous mining machine according to claim 1, characterized in that: The length of the deep mining tunnel (8) is 10m to 50m.

3. A method for mining and filling a corner coal full negative pressure continuous mining machine according to claim 2, characterized in that: The width of the deep mining cave (8) is the mining width of the continuous mining machine (17), the width of each block is 4 to 6 mining cave widths, the width of the isolation coal pillar (9) is 1 to 2 mining cave widths, and the width of the unit cross section (10) is 1 mining cave width.

4. A method for mining and filling corner coal with a full negative pressure continuous mining machine according to claim 1, characterized in that: In step three, the goaf (12) is filled by extending the filling pipe (21) along the top plate of the filling branch tunnel (4) through the filling hole reserved at the upper end of the tail isolation device of the filling support (16) into the goaf (12), and opening the gate valve on the filling pipe (21) to fill until the filling body (22) fills the goaf (12) of the innermost block.

5. The method for mining and filling corner coal with a full negative pressure continuous mining machine according to claim 1, characterized in that: In the step three, the detachable retaining wall (19) is inserted into the surrounding rock of the mining branch tunnel (3) on all sides, and the mining side of the detachable retaining wall (19) is closely attached with an isolation membrane (20) to seal the mining branch tunnel (3).

6. The mining and filling equipment used in the mining and filling method of the full negative pressure continuous mining machine for corner coal as claimed in any one of claims 1 to 5 is characterized in that: The invention comprises a continuous mining machine (17), a mining support (15), a filling support (16), a wind barrier (18) and a detachable retaining wall (19); the mining support (15) is arranged in a mining branch tunnel (3) at one end of a deep mining tunnel (8) immediately following the continuous mining machine (17); the filling support (16) is arranged in a filling branch tunnel (4) at the other end of the deep mining tunnel (8); during mining, the wind barrier (18) crosses the goaf (12) and is hung between the mining support (15) and the filling support (16); during filling, the filling support (16) and the detachable retaining wall (19) are arranged in the branch tunnels at both ends of the isolation coal pillar (9) to seal the goaf (12) of the entire block.

7. The mining and filling equipment for a full negative pressure continuous mining machine for corner coal according to claim 6 is characterized in that: The filling support (16) comprises a support body and a tail isolation device arranged on the support body; the support body comprises a top beam (166), a base (167) and a support column (168); the tail isolation device comprises a tail beam (161), a tail seat (162), an isolation plate (163), an inclined support column (164) and a film roller (165); the tail of the top beam (166) is connected to the tail beam (161), the tail of the base (167) is connected to the tail seat (162), and the tail beam (161) and the tail seat (162) are still supported by the support column (168); the tail of the tail seat (162) is connected to the isolation plate (163), the base (167) and the isolation plate (163) are connected to the inclined support column (164), the film roller (165) is suspended below the tail of the top beam (166), and the film roller (165) is equipped with an isolation film (20).

8. The mining and filling equipment for a full negative pressure continuous mining machine for corner coal according to claim 7 is characterized in that: The isolation plate (163) is a combined plate that can be combined and spliced ​​upward and leftward and rightward; when the filling support (16) blocks the goaf (12), the film roller (165) is first rotated to pull the isolation film (20) onto the bottom plate of the goaf side branch tunnel of the isolation plate (163), and then the isolation plates (163) are combined and spliced ​​to close the filling branch tunnel (4).

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