Fluidized coal mining method using energy storage of coal seam

Abstract

A fluidized coal mining method using energy storage of a coal seam, comprising the steps of mine shaft development, active coal uncovering, and fluidized coal mining. According to the method, a dynamic phenomenon is induced by means of active coal uncovering, a coal mining borehole (12) is established from the ground to a coal seam (1), hydraulic in-situ cutting is performed on the coal seam (1), a coal-rock mixture produced after hydraulic cutting flows into a roadway system along a floor roadway (4), and then coal, gangue, and water in the mixture are separated and are recycled in the subsequent coal mining process, achieving underground unmanned fluidized coal mining, and high crushing of coal bodies is achieved in the active coal uncovering process, thereby making hydraulic coal mining more efficient, and reducing the water resource consumption in the coal mining process.

Description

A fluidized coal mining method utilizing the coal seam's own energy storage Technical Field

[0001] The present invention belongs to the technical field of coal mining, and in particular relates to a fluidized coal mining method utilizing the energy storage of the coal seam itself. Background Art

[0002] For a considerable period of time to come, coal will remain my country's most important basic energy source and industrial raw material, playing an irreplaceable role in economic and social development. Currently, with the exception of a small amount of open-pit mining, over 90% of China's coal mines utilize underground mining methods, where coal is mined through underground tunnels and transported to the surface via a transportation system. This traditional underground mining method requires the construction of numerous underground tunnels and supporting production chambers, resulting in extensive geotechnical engineering and high coal mining costs. Furthermore, although mechanized mining has been achieved, underground equipment installation and operation still require a large number of workers, leading to significant casualties in the event of a coal and gas outburst. Therefore, underground mining is not a safe method.

[0003] Coal and gas outburst (abbreviated as outburst) is a violent dynamic process in which gas-containing coal and rock in a crushed state move rapidly from the coal and rock layer to the mining space in a coal mine, accompanied by a large amount of gas ejection, which seriously threatens the safe production of coal mines. In recent years, research has focused on how to prevent the occurrence of outburst accidents. However, precisely because the outburst process is accompanied by a large amount of energy release, if the large amount of energy such as gas pressure energy, coal body potential energy and ground stress stored in the coal seam itself is released instantly and acts on the coal body through artificial coal mining, the coal body will be broken in a very short time. If this dynamic disaster is fully utilized as an effective way to break the coal body, it will save a lot of coal mining work.

[0004] Physical fluidized coal mining refers to a mining technology that uses water power to complete all or part of the work in the production links of mine production, such as coal mining, transportation, and hoisting. The physical fluidized coal mining method can greatly reduce the configuration of underground tunnels and underground workers. The coal mining cost is low and the coal mining safety is high. Physical fluidized coal mining is usually used in unstable coal seams, steeply inclined coal seams, re-mined coal seams, and areas or blocks with irregular coal seam occurrence. As long as the coal seam conditions are suitable, its advantages can be fully utilized.

[0005] After consulting the existing relevant research literature, it is known that the published patents and literature have done some research on fluidized coal mining technology. The Chinese invention patent with application number 202110758090.0 discloses a ground directional drilling fluidized hydraulic coal mining method. This method is based on directional drilling technology. A directional coal mining drill is drilled from the ground at a high position relative to the coal seam. At the same time, a directional coal suction drill is drilled from the ground to the coal seam. Then, the coal seam is hydraulically cut by an integrated drilling and mining device, which can reduce the cost of coal mining under the premise of achieving underground operations without operators. However, its coal mining process relies entirely on hydraulic and drilling and mining integrated devices, and does not mention the recycling of water and gangue resources, nor does it mention the separation and treatment of the mined coal-rock mixture.

[0006] Therefore, in order to further achieve low-cost and high-efficiency fluidized coal mining, it is urgent to propose a fluidized coal mining method that utilizes the energy storage of the coal seam itself.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to provide a fluidized coal mining method that utilizes the energy storage of the coal seam itself to solve the above problems.

[0009] To achieve the above object, the present invention provides the following solutions:

[0010] A fluidized coal mining method utilizing the energy storage of the coal seam itself comprises the following steps:

[0011] Development of shafts and tunnels: Detecting and determining the depth, size and inclination of the coal seam to be mined, demarcating different mining areas and the mining sequence; drilling the coal seam through a drilling system to form a vertical hoist shaft; developing a tunnel system along the bottom of the vertical hoist shaft and installing a surface equipment system on the ground; the tunnel system is placed below the coal seam;

[0012] Active coal uncovering: delivering explosives to the roadway system through the lifting shaft, sealing the top of the lifting shaft, detonating the explosives to disturb the coal seam and generate coal and gas outburst dynamic phenomena; processing the fluid mixture formed by the explosion through the surface equipment system;

[0013] Fluidized coal mining: The location of the coal mining drill is determined on the ground according to the location of the protruding holes formed after active coal mining, and the coal mining drill is drilled to the upper part of the tunnel system by the drilling system to form a mining area; the mining area is mined;

[0014] Backfilling of goaf: After the first mining area is mined, a goaf is formed, and the goaf is transported to the goaf through the ground equipment system for backfilling, so that the goaf and the roadway system form a gangue backfill area;

[0015] After backfilling is completed, the above steps are repeated to mine the next adjacent coal mining area in turn until the mining of the entire coal seam is completed.

[0016] In the coal seam mining step, the surface equipment system includes a gas filtering and compression device, a gas storage tank, a sedimentation tank, a mixture separation device, a gangue storage chamber, a water storage tank, a high-pressure pump and a coal storage bin;

[0017] The gas compression and filtering device is tightly connected to the gas extraction hole opened at the top of the lifting shaft; the gas compression and filtering device is tightly connected to the gas storage tank through a gas delivery pipeline;

[0018] One end of the mixture separation device is connected to the sedimentation tank opened on the ground through a conveying pipeline; the other end is connected to the gangue storage room, water storage tank and coal storage bin through valves respectively; the water storage tank is tightly connected to the high-pressure pump through a water supply pipeline.

[0019] In the coal seam mining step, the drilling system includes a coal-rock mixture delivery pipe disposed in the lifting shaft; a slurry suction pump and a crushing and stirring device are installed at the bottom end of the coal-rock mixture delivery pipe, and the top end is connected to the sedimentation tank;

[0020] The top of the lifting shaft is sealed by a shaft sealing unit.

[0021] In the fluidized coal mining step, the drilling system further includes a coal mining drill rod disposed in the coal mining well; the inner cavity of the coal mining drill rod is tightly connected to the output end of a high-pressure water pipe, and the input end of the high-pressure water pipe is connected to the high-pressure pump;

[0022] The bottom end of the coal mining drill rod is transmission connected to the coal mining drill rig, and a rotation control device is also installed at the bottom of the coal mining drill rod. A high-pressure ejector is fixedly installed on the rotation control device through an injection distance telescopic rod, and a hollow water passage is opened in the injection distance telescopic rod, and the hollow water passage is connected to the inner cavity of the coal mining drill rod.

[0023] The tunnel system includes a coal and rock collection chamber and a floor tunnel; the bottom end of the lifting shaft is connected to the coal and rock collection chamber; the floor tunnel is excavated along the coal and rock collection chamber, and the floor tunnel is connected to the coal seam through a stone gate.

[0024] In the active coal uncovering step, the specific steps are to send the explosives to the stone gate at the bottom of the coal seam through the lifting shaft, seal the top of the lifting shaft through the wellhead sealing unit, detonate the explosives to disturb the coal seam; the fluid mixture formed by the explosion enters the coal and rock collection chamber through the bottom plate tunnel and is then stored in the gas storage tank through the gas extraction hole.

[0025] In the fluidized coal mining step, drilling the coal mining well to the upper part of the tunnel system through the drilling system and stopping specifically includes: arranging the high-pressure pump and the water storage tank at the wellhead of the coal mining well, extending the coal mining drill rod into the coal mining well, and opening the coal mining well through the coal mining drill rig; after completing the drilling of the coal mining well, continue drilling the coal seam drilling section into the coal seam until drilling reaches the upper part of the stone gate and stops drilling.

[0026] In the fluidized coal mining step, forming the mining area specifically includes: hydraulically cutting the loose coal seam around the protruding hole by the high-pressure jet; controlling the coal mining drill rod to slowly retract until the high-pressure jet retracts to the top of the coal seam drilling section, completing the initial mining;

[0027] The coal mining drill rod is controlled to descend and reset so that the high-pressure ejector reaches the lower limit position of the coal seam burial depth, and the ejection distance telescopic rod is extended to increase the effective ejection distance of the high-pressure ejector and increase the water pressure to expand the hydraulic coal breaking radius. This cycle is repeated until the first mining area is mined.

[0028] In the fluidized coal mining step, mining the mining area includes: the coal-rock mixture cut in the mining area enters the coal-rock collection chamber along the bottom plate tunnel, and is lifted into the sedimentation tank through the slurry suction pump and the crushing and stirring device.

[0029] In the fluidized coal mining step, backfilling the goaf includes: constructing a blocking unit in the floor roadway below the coal seam adjacent to the goaf; transporting the gangue in the gangue storage chamber to the goaf through the gangue conveying pipe for backfilling, so that the goaf and the floor roadway below form a gangue backfill area;

[0030] After the backfilling is completed, the above steps are repeated to mine the next adjacent mining area in turn until the mining of the coal seam is completed, and the coal and rock collection chamber and the lifting shaft are backfilled.

[0031] Compared with the existing technology, the present invention has the following advantages and technical effects: The present invention proposes a fluidized coal mining method that utilizes the energy stored in the coal seam itself. Before carrying out traditional physical fluidized coal mining, the coal body at a predetermined position is actively and controllably exposed to induce dynamic phenomena. By utilizing the large amount of energy such as gas expansion energy and ground stress energy stored in the coal seam itself to act on the coal body itself, it not only effectively controls coal and gas outburst disasters, but also achieves the initial high degree of crushing of the coal body, truly turning waste into treasure. It also causes the coal body around the hole to loosen, saving a lot of work for subsequent hydraulic mining and improving the overall coal mining efficiency.

[0032] During the coal mining process, gas released from the coal seam and coal particles is collected simultaneously. At the same time, the coal-rock mixture lifted up the well is separated into coal, water, and gangue through a separation device. The separated water is returned to the water storage tank and recycled in fluidized coal mining, while the gangue is used to backfill the goaf. This fully utilizes resources during the coal mining process, effectively saving production costs while achieving green and efficient co-mining of coal and gas.

[0033] A complete fluidized coal mining process that utilizes the coal seam's own energy storage has been developed. The mining area and mining sequence are optimized based on the actual conditions of the coal seam. At the same time, a spray distance telescopic rod is added to the fixed drill rod for coal mining, which can change the spray range of the high-pressure jet and increase the size of the single mining area, greatly improving the coal mining efficiency and reducing the drilling construction workload. At the same time, through the cyclic backfilling of the goaf and floor tunnels, coal pillars can be eliminated. Combined with the rotary control device and the spray distance telescopic rod, the corner coal and residual coal can be effectively crushed. Compared with traditional coal mining methods, the coal recovery rate can be increased by about 20%, basically achieving 100% coal recovery and effectively avoiding the waste of coal resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work.

[0035] FIG1 is a schematic diagram of active coal uncovering during the fluidized coal mining method utilizing the coal seam's own energy storage;

[0036] FIG2 is a schematic diagram of fluidized mining during a fluidized coal mining method utilizing the energy storage of the coal seam itself;

[0037] FIG3 is a schematic diagram of backfilling of goaf and mining of adjacent blocks during the fluidized coal mining method utilizing the energy storage of the coal seam itself;

[0038] Among them, 1. Coal seam; 2. Hoisting shaft; 3. Coal and rock collection chamber; 4. Floor roadway; 5. Stone gate; 6. Protruding hole; 7. Loose coal body area; 8. Gas extraction hole; 9. Gas filtration and compression device; 10. Gas storage tank; 11. Wellhead sealing unit; 12. Coal drilling; 13. Coal drilling rod; 14. High-pressure water pipe; 15. Coal drilling rig; 16. Rotation control device; 17. High-pressure ejector; 18. Spray distance telescopic rod; 19. Coal seam drilling section; 20. Sedimentation tank; 21. Mixture separation device; 22. Gangue storage chamber; 23. Water storage tank; 24. High-pressure pump; 25. Coal storage bin; 26. Slurry suction pump; 27. Crushing and stirring device; 28. Coal-rock mixture conveying pipe; 29. ​​Sealing unit; 30. Gangue conveying pipe; 31. Goaf; 32. Gangue backfill area; 33. Boundary of mining area. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] A fluidized coal mining method utilizing the energy storage of the coal seam itself comprises the following steps:

[0042] Development of shafts and tunnels: Detect and determine the depth, size, and inclination of the coal seam 1 to be mined, delineate different mining areas and the mining sequence; drill the coal seam 1 using a drilling system to form a vertical hoist shaft 2; develop a tunnel system along the bottom of the vertical hoist shaft 2 and install a surface equipment system on the ground; the tunnel system is placed below the coal seam 1;

[0043] Active coal uncovering: Explosives are delivered to the roadway system through the hoist shaft 2, the top of the hoist shaft 2 is sealed, and the explosives are detonated to disturb the coal seam 1, causing coal and gas outburst dynamic phenomena; the fluid mixture formed by the explosion is processed by the surface equipment system;

[0044] Fluidized coal mining: The position of the coal mining drill 12 is determined on the ground according to the position of the protruding hole 6 formed after active coal mining, and the coal mining drill 12 is drilled to the upper part of the tunnel system through the drilling system to form a mining area; the mining area is mined;

[0045] Backfilling of the goaf: After the first mining area is mined, a goaf 31 is formed. The goaf 31 is transported to the goaf 31 through the surface equipment system for backfilling, so that the goaf 31 and the roadway system form a gangue backfill area 32;

[0046] After the backfilling is completed, the above steps are repeated to mine the next adjacent coal mining area in turn until the mining of the entire coal seam 1 is completed.

[0047] In the coal seam mining step, the surface equipment system includes a gas filtering and compression device 9, a gas storage tank 10, a sedimentation tank 20, a mixture separation device 21, a gangue storage chamber 22, a water storage tank 23, a high-pressure pump 24 and a coal storage bin 25;

[0048] The gas compression, filtering and compression device 9 is tightly connected to the gas extraction hole 8 opened at the top of the lifting shaft 2; the gas compression, filtering and compression device 9 is tightly connected to the gas storage tank 10 through a gas transmission pipeline;

[0049] One end of the mixture separation device 21 is connected to the sedimentation tank 20 opened on the ground through a delivery pipe; the other end is connected to the gangue storage chamber 22, the water storage tank 23 and the coal storage bin 25 through valves respectively; the water storage tank 23 is sealedly connected to the high-pressure pump 24 through a water delivery pipe.

[0050] In the coal seam mining step, the drilling system includes a coal-rock mixture delivery pipe 28 disposed in the lifting shaft 2; a slurry suction pump 26 and a crushing and stirring device 27 are installed at the bottom end of the coal-rock mixture delivery pipe 28, and the top end is connected to the sedimentation tank 20;

[0051] The top of the hoist shaft 2 is sealed by a shaft sealing unit 11 .

[0052] In the fluidized coal mining step, the drilling system further includes a coal mining drill rod 13 disposed in the coal mining well 12; the inner cavity of the coal mining drill rod 13 is tightly connected to the output end of the high-pressure water pipe 14, and the input end of the high-pressure water pipe 14 is connected to the high-pressure pump 24;

[0053] The bottom end of the coal mining drill rod 13 is transmission connected to the coal mining drill rig 15. A rotation control device 16 is also installed at the bottom of the coal mining drill rod 13. A high-pressure ejector is fixedly installed on the rotation control device 16 through an injection distance telescopic rod 18. A hollow water passage is opened in the injection distance telescopic rod 18, and the hollow water passage is connected to the inner cavity of the coal mining drill rod 13.

[0054] The tunnel system includes a coal and rock collection chamber 3 and a floor tunnel 4; the bottom end of the lifting shaft 2 is connected to the coal and rock collection chamber 3; a floor tunnel 4 is excavated along the coal and rock collection chamber 3, and the floor tunnel 4 is connected to the coal seam through a stone gate 5.

[0055] In the active coal mining step, the specific steps are to send the explosives to the stone gate 5 at the bottom of the coal seam 1 through the lifting shaft 2, seal the top of the lifting shaft 2 through the wellhead sealing unit 11, detonate the explosives to disturb the coal seam 1; the fluid mixture formed by the explosion enters the coal and rock collection chamber 3 through the bottom plate tunnel 4 and is then stored in the gas storage tank 10 through the gas extraction hole 8.

[0056] In the fluidized coal mining step, the coal mining drill 12 is drilled to the upper part of the tunnel system by the drilling system and stopped, which specifically includes: arranging a high-pressure pump 24 and a water storage tank 23 at the wellhead of the coal mining drill 12, extending the coal mining drill rod 13 into the coal mining drill 12, and opening the coal mining drill 12 by the coal mining drill rig 15; after completing the drilling of the coal mining drill 12, continue to drill the coal seam drilling section 19 into the coal seam 1 until drilling reaches the upper part of the stone gate 5 and stops drilling.

[0057] In the fluidized coal mining step, the formation of the mining area specifically includes: using the high-pressure jet 17 to hydraulically cut the loose coal seam around the protruding hole 6; controlling the coal mining drill rod 13 to slowly retract until the high-pressure jet 17 retracts to the top of the coal seam drilling section 19, completing the initial mining;

[0058] The coal mining drill rod 13 is controlled to descend and reset so that the high-pressure ejector 17 reaches the lower limit of the coal seam burial depth. The ejection distance telescopic rod 18 is extended to increase the effective ejection distance of the high-pressure ejector 17 and increase the water pressure to expand the hydraulic coal breaking radius. This cycle is repeated until the first mining area is mined.

[0059] In the fluidized coal mining step, mining the mining area includes: the coal-rock mixture cut in the mining area enters the coal-rock collection chamber 3 along the bottom plate tunnel 4, and is lifted into the sedimentation tank 20 through the slurry suction pump 26 and the crushing and stirring device 27.

[0060] In the fluidized coal mining step, backfilling the goaf includes: constructing a plugging unit 29 in the lower floor roadway 4 adjacent to the coal seam 1 in the goaf; transporting the gangue in the gangue storage chamber 22 to the goaf 31 through the gangue conveying pipe 30 for backfilling, so that the goaf 31 and the lower floor roadway 4 form a gangue backfill area 32;

[0061] After the backfilling is completed, the above steps are repeated to mine the next adjacent mining area in turn until the mining of the coal seam 1 is completed, and the coal and rock collection chamber 3 and the lifting shaft 2 are backfilled.

[0062] In one embodiment of the present invention, in the active coal stripping step, explosives are detonated to disturb the coal seam 1 to cause dynamic phenomena such as coal and gas outbursts, so that a large amount of gas expansion energy, ground stress energy and gravitational potential energy stored in the coal seam 1 are instantaneously released and act on the coal seam 1 itself to achieve the purpose of highly crushing the coal seam 1 to complete the active coal stripping, forming a fluid mixture of coal, rock, gas, water, etc.; to achieve the initial high crushing of the coal body, and cause the coal body around the protruding holes to loosen, thereby improving the efficiency of subsequent fluidized coal mining and hydraulic coal mining.

[0063] In one embodiment of the present invention, the floor tunnel 4 is inclined at a 5° angle to the coal seam 1, ensuring that the coal-rock mixture that is protruding and hydraulically broken can be automatically transported to the coal-rock collection chamber 3 under the conditions of continuous expansion of gas and its own gravity, thereby avoiding blockage of the floor tunnel 4.

[0064] Furthermore, a coal mining drill 12 is used to drill into the protruding hole 6, and the coal seam 1 surrounding the protruding hole 6 is hydraulically cut in situ. The hydraulically cut coal-rock mixture flows along the floor roadway 4 into the coal-rock collection chamber 3, and is then lifted up the well by a slurry pump 26 and into the sedimentation tank 20, achieving efficient fluidized coal mining.

[0065] In one embodiment of the present invention, gas is extracted simultaneously during the coal mining process. At the same time, the coal-rock mixture is lifted up the well by the slurry pump 26 and enters the sedimentation tank 20, and then separated into coal, water and gangue by the mixture separation device 21. The coal is transported to the coal storage bin 25, and the water is sent to the water storage tank 23 through the water pipe for recycling. The gas released by the coal seam and the crushed coal particles during the coal mining process enters the gas filtering and compression device 9 through the gas extraction hole 8, and the separated water stored in the gas storage tank 10 is returned to the water storage tank 23 for recycling in fluidized coal mining. The gangue is used for backfilling the goaf 31 and the bottom plate tunnel 4, thereby realizing full utilization of resources in the coal mining process.

[0066] In one embodiment of the present invention, by extending the injection distance telescopic rod 18, the injection range of the high-pressure ejector 17 can be effectively improved, the size of a single mining area is increased, so as to reduce drilling construction work and improve coal mining efficiency.

[0067] In one embodiment of the present invention, the mining area is delineated in advance according to the coal seam conditions, and the goaf 31 and the bottom plate tunnel 4 of the previous block are backfilled before mining the current block to prevent the roof from collapsing during subsequent mining. Therefore, there is no need to leave coal pillars during the subsequent mining process, effectively improving the coal resource recovery rate.

[0068] In one embodiment of the present invention, backfill is performed on the mining area boundary 33 formed between the mining area adjacent to the goaf and the goaf; the mining areas adjacent to the goaf are mined sequentially, and the stone gates 5 at the bottom of the remaining mining areas are formed by extending along the bottom plate tunnel 4; the bottom plate tunnel 4 at the bottom of the goaf and the stone gates 5 at the bottom of the remaining mining areas are cut off by a construction sealing unit.

[0069] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0070] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A fluidized coal mining method utilizing the energy storage of the coal seam itself, characterized in that: The following steps are involved: Development of shafts and tunnels; detecting and determining the buried depth, size and inclination of the coal seam (1) to be mined, demarcating different mining areas and mining sequences; drilling the coal seam (1) through a drilling system to form a lifting shaft (2); developing a tunnel system along the bottom of the lifting shaft (2), and installing a ground equipment system on the ground; the tunnel system is placed below the coal seam (1); Active coal uncovering: sending explosives to the tunnel system through the lifting shaft (2), sealing the top of the lifting shaft (2), and detonating the explosives to disturb the coal seam (1) to cause coal and gas outburst dynamic phenomena; Processing the fluid mixture formed by the explosion through the ground equipment system; Fluidized coal mining: determining the position of a coal mining drill (12) on the ground according to the position of the protruding hole (6) formed after active coal mining, and drilling the coal mining drill (12) to the upper part of the tunnel system through a drilling system to stop, thereby forming a mining area; and mining the mining area; Backfilling of the goaf: after the first mining area is mined, a goaf (31) is formed, and the goaf (31) is transported to the goaf (31) through the ground equipment system for backfilling, so that the goaf (31) and the roadway system form a gangue backfill area (32); After the backfilling is completed, the above steps are repeated to mine the next adjacent coal mining area in turn until the mining of the entire coal seam (1) is completed.

2. A fluidized coal mining method utilizing the energy storage of the coal seam itself according to claim 1, characterized in that: In the step of mining the coal seam, the surface equipment system includes a gas filtering and compressing device (9), a gas storage tank (10), a sedimentation tank (20), a mixture separation device (21), a gangue storage chamber (22), a water storage tank (23), a high-pressure pump (24) and a coal storage bin (25); The gas compression and filtering device (9) is tightly connected to the gas extraction hole (8) opened at the top of the lifting shaft (2); the gas compression and filtering device (9) is tightly connected to the gas storage tank (10) via a gas delivery pipeline; One end of the mixture separation device (21) is connected to the sedimentation tank (20) opened on the ground through a conveying pipeline; the other end is connected to the gangue storage chamber (22), the water storage tank (23) and the coal storage bin (25) through valves respectively; the water storage tank (23) is tightly connected to the high-pressure pump (24) through a water delivery pipeline.

3. A fluidized coal mining method utilizing the energy storage of the coal seam itself according to claim 2, characterized in that: In the coal seam mining step, the drilling system comprises a coal-rock mixture conveying pipe (28) arranged in the lifting shaft (2); a slurry suction pump (26) and a crushing and stirring device (27) are installed at the bottom end of the coal-rock mixture conveying pipe (28), and the top end is connected to the sedimentation tank (20); The top of the lifting shaft (2) is sealed by a shaft sealing unit (11).

4. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 2 is characterized in that: In the fluidized coal mining step, the drilling system further comprises a coal mining drill rod (13) arranged in the coal mining drilling well (12); the inner cavity of the coal mining drill rod (13) is tightly connected to the output end of the high-pressure water pipe (14), and the input end of the high-pressure water pipe (14) is connected to the high-pressure pump (24); The bottom end of the coal mining drill rod (13) is transmission-connected to the coal mining drill rig (15), and a rotation control device (16) is also installed at the bottom of the coal mining drill rod (13). A high-pressure ejector is fixedly installed on the rotation control device (16) via an injection distance telescopic rod (18), and a hollow water passage is opened in the injection distance telescopic rod (18), and the hollow water passage is communicated with the inner cavity of the coal mining drill rod (13).

5. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 2, characterized in that: The tunnel system comprises a coal and rock collection chamber (3) and a floor tunnel (4); the bottom end of the lifting shaft (2) is connected to the coal and rock collection chamber (3); the floor tunnel (4) is excavated along the coal and rock collection chamber (3), and the floor tunnel (4) is connected to the coal seam through a stone door (5).

6. A fluidized coal mining method utilizing the energy storage of the coal seam itself according to claim 5, characterized in that: In the active coal uncovering step, the specific steps are as follows: delivering explosives to the stone gate (5) at the bottom of the coal seam (1) through the lifting shaft (2), sealing the top of the lifting shaft (2) through a wellhead sealing unit (11), detonating the explosives to disturb the coal seam (1); the fluid mixture formed by the explosion enters the coal-rock collection chamber (3) through the bottom plate tunnel (4) and is then stored in the gas storage tank (10) through the gas extraction hole (8).

7. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 4, characterized in that: In the fluidized coal mining step, drilling the coal mining borehole (12) to the upper part of the tunnel system by means of a drilling system and stopping specifically comprises: arranging the high-pressure pump (24) and the water storage tank (23) at the wellhead position of the coal mining borehole (12), extending the coal mining drill rod (13) into the coal mining borehole (12), and opening up the coal mining borehole (12) by means of the coal mining drill rig (15); after completing the drilling of the coal mining borehole (12), continuing to drill the coal seam drilling section (19) into the coal seam (1) until drilling reaches the upper part of the stone gate (5) and stopping drilling.

8. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 7, characterized in that: In the fluidized coal mining step, forming a mining area specifically includes: hydraulically cutting the loose coal seam around the protruding hole (6) by the high-pressure jet (17); controlling the coal mining drill rod (13) to slowly retreat until the high-pressure jet (17) retreats to the top of the coal seam drilling section (19), thereby completing preliminary mining; The coal mining drill rod (13) is controlled to descend and reset so that the high-pressure ejector (17) reaches the lower limit position of the coal seam burial depth, and the ejection distance telescopic rod (18) is extended to increase the effective ejection distance of the high-pressure ejector (17) and increase the water pressure to expand the hydraulic coal breaking radius, and this cycle is repeated until the first mining area is mined.

9. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 3, characterized in that: In the fluidized coal mining step, mining the mining area includes: the coal-rock mixture cut from the mining area enters the coal-rock collection chamber (3) along the bottom plate tunnel (4), and is lifted into the sedimentation tank (20) by the slurry suction pump (26) and the crushing and stirring device (27).

10. The fluidized coal mining method using the energy storage of the coal seam itself according to claim 5, characterized in that: In the fluidized coal mining step, backfilling the goaf includes: constructing a plugging unit (29) in the floor tunnel (4) below the coal seam (1) adjacent to the goaf (31); transporting the gangue in the gangue storage chamber (22) to the goaf (31) through the gangue transport pipe (30) for backfilling, so that the goaf (31) and the floor tunnel (4) below form a gangue backfill area (32); After the backfilling is completed, the above steps are repeated to mine the next adjacent mining area in turn until the mining of the coal seam (1) is completed, and the coal and rock collection chamber (3) and the lifting shaft (2) are backfilled.

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