Active anti-blocking bunker system for coal mine underground coal bunker grading partition coal dropping

Abstract

The invention provides an active anti-blocking bunker system for grading zoning coal falling of an underground coal mine bunker, and belongs to the technical field of coal briquette storage. The device comprises a coal conveying device, a multi-stage drum screen and a graded coal briquette conveying device. Raw coal is screened in a classified mode through the multi-stage drum screen, the classified coal briquette conveying device is used for accurately conveying coal briquettes of different grades to the preset area in the coal bunker, classified stacking of the coal briquettes of different grades is achieved, coal briquette graded screening and partitioned coal falling are achieved from the source, and the risk of bunker blockage is actively prevented and controlled. The system thoroughly abandons a traditional passive dredging mode, eliminates potential safety hazards of dredging operations such as manual work and blasting, and remarkably improves the safety production level and the transportation efficiency of a coal mine by optimizing a coal briquette stacking structure in the coal bunker, greatly improving the fluidity of coal briquettes and reducing the production interruption time caused by bunker blockage; and meanwhile, the equipment maintenance cost and the accident treatment cost are reduced, and remarkable economic benefits and social benefits are achieved.

Description

Technical Field

[0001] This invention relates to the field of coal storage technology, and in particular to an active anti-blocking system for graded and zoned coal falling in underground coal bunkers. This active anti-blocking system is applicable to the prevention and control of blockage and collapse in various types of underground coal bunkers, and is especially suitable for large and medium-sized coal mines with low gas content and medium hydrogeological conditions. Background Technology

[0002] Underground coal bunkers are the core storage and transfer facilities in coal mine transportation systems, and their stable operation directly affects the continuous production efficiency of mining areas and the safety of underground operations. However, in current coal mine production, the coal blocks mined from the working face are of mixed particle sizes and enter the coal bunker directly without being graded. This results in the disorderly accumulation of coal blocks inside the bunker, with coal gangue, sticky mixtures, and coal blocks of different particle sizes sticking together and compacting, easily forming caking and blockages, leading to bunker blockage accidents.

[0003] To address coal bunker blockage, existing technologies primarily employ passive clearing methods, including manual clearing, blasting vibration clearing, air cannon vibration clearing, and intelligent mechanical clearing. However, these methods have significant drawbacks: manual clearing requires workers to operate in high-risk areas, increasing the risk of injury or death due to coal gangue instability and collapse; blasting clearing requires strict control of explosive dosage and gas concentration, involves complex procedures, and may damage the coal bunker structure; while air cannon and intelligent mechanical clearing offer high levels of automation, they cannot fundamentally eliminate blockage, have high equipment maintenance costs, and still carry the risk of bunker collapse during the clearing process.

[0004] In recent years, coal mine bunker collapses have occurred frequently, causing heavy casualties and economic losses. The root cause of these accidents lies in the lack of effective means to prevent bunker blockages at the source using existing technology. Passive handling methods are insufficient to eliminate safety hazards, severely restricting the improvement of coal mine safety production levels. There is an urgent need for a proactive, safe, and efficient bunker blockage prevention technology solution. Summary of the Invention

[0005] In view of this, to address the frequent technical problems of coal bunker blockage and collapse accidents in existing underground coal mines, this invention provides an active anti-blockage system for graded and zoned coal delivery in underground coal bunkers. The system uses a multi-stage drum screen to grade and screen raw coal, and a graded coal block conveying device to precisely transport coal blocks of different grades to preset areas within the coal bunker. This achieves graded stacking of coal blocks of different grades, realizing coal block grading and zoned delivery from the source, and actively preventing the risk of blockage. This system completely abandons traditional passive unblocking methods, eliminating the safety hazards of manual and blasting unblocking operations. By optimizing the coal block stacking structure within the coal bunker, it significantly improves coal block flowability, reduces production interruption time caused by blockage, and significantly improves the level of safe production and transportation efficiency in coal mines. Simultaneously, it reduces equipment maintenance costs and accident handling costs, resulting in significant economic and social benefits.

[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides an active anti-blocking system for graded and zoned coal falling in underground coal bunkers, comprising: Coal conveying equipment, used to transport raw coal mined from the working face; Multi-stage drum screens are arranged sequentially along the conveying direction of the main coal conveyor belt. The screen aperture size of each stage of the drum screen increases sequentially along the conveying direction of the raw coal. They are used to perform multi-stage screening of the raw coal to obtain coal blocks of different grades. A graded coal conveying device is used to transport coal blocks of different grades to the coal bunker separately. The coal bunker has tiered stacking spaces for stacking coal blocks of different grades.

[0007] Compared with the prior art, the present invention has the following beneficial effects: Proactively controlling the risk of coal blockage: Raw coal is graded and screened at the source using a multi-stage drum screen. A graded coal block conveying device precisely transports coal blocks of different grades to predetermined areas within the coal bunker, achieving graded stacking of coal blocks of different grades. This proactively controls the risk of blockage by implementing coal block grading and screening at the source. This system completely abandons traditional passive unblocking methods, eliminating the safety hazards of manual and blasting unblocking operations. By optimizing the coal block stacking structure within the coal bunker, it significantly improves coal block flowability, reduces production interruption time caused by blockage, and significantly improves the level of safe production and transportation efficiency in coal mines. Simultaneously, it reduces equipment maintenance costs and accident handling costs, resulting in significant economic and social benefits.

[0008] Improve transportation and production efficiency: Graded coal blocks have good fluidity, the coal discharge process is smooth, reducing production interruption time caused by blockage and improving the continuous production efficiency of the mining area.

[0009] Highly intelligent and adaptable: Integrated with bin monitoring, it can monitor the height of each bin in real time and automatically adjust the amount of coal dropped, realizing automated and precise control of the coal dropping process, reducing manual intervention, and adapting to the needs of intelligent transformation of modern coal mines.

[0010] Easy to promote and apply: The core equipment adopts commonly used coal mine drum screens, belt conveyors, etc., which are easy to modify, easy to install and maintain, and do not require large-scale modification of the existing coal bunker main structure, making them widely applicable. Attached Figure Description

[0011] Figure 1 A schematic diagram of an active anti-blocking system for graded and zoned coal delivery in underground coal bunkers; Figure 2 A schematic diagram of the reversible distribution conveyor belt layout at the entrance of the underground coal bunker. Figure 3A schematic diagram of the graded and zoned stacking structure of coal blocks of different grades in an underground coal bunker; In the diagram, 0 is the coal bunker; 1 is the main coal conveyor belt; 2 is the buffer transition plate; 3 is the primary drum screen; 4 is the branch conveyor belt of the primary drum screen; 5 is the secondary drum screen; 6 is the branch conveyor belt of the secondary drum screen; 7 is the tertiary drum screen; 8 is the branch conveyor belt of the tertiary drum screen; 9 is the impact-resistant, wear-resistant, and smooth lining of the ultra-high molecular weight polyethylene plastic sheet; 10 is the reversible batching belt conveyor for transporting large-particle-grade coal blocks; 11 is the reversible batching belt conveyor for transporting medium-particle-grade coal blocks; 12 is the outer ring area of ​​the coal bunker where large-particle-grade coal blocks are accumulated; 13 is the middle ring area of ​​the coal bunker where medium-particle-grade coal blocks are accumulated; and 14 is the central cylindrical area of ​​the coal bunker where small-particle-grade coal blocks are accumulated. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0013] like Figure 1-3 As shown, the present invention provides an active anti-blocking system for graded and zoned coal falling in underground coal bunkers in coal mines, characterized in that it includes: A coal conveying device is used to transport raw coal mined from the working face. Preferably, the coal conveying device is a main coal conveyor belt 1, which is installed between the underground working face and the coal bunker opening.

[0014] Multi-stage drum screens are sequentially arranged along the conveying direction of the main coal conveyor belt 1 and installed in the section of the coal conveying device near the coal bunker opening. The screen aperture size of each stage of the drum screen increases sequentially along the raw coal conveying direction. They are used to perform multi-stage screening of raw coal to obtain coal blocks of different grades.

[0015] A graded coal conveying device is used to transport coal blocks of different grades separately to a coal bunker. The graded coal conveying device is preferably a branched conveyor belt. The coal bunker has graded stacking spaces for stacking coal blocks of different grades.

[0016] This technical solution uses a coal conveying device to transport raw coal mined from the working face to a multi-stage drum screen area. The multi-stage drum screen is set along the direction of raw coal conveying, with the screen aperture size increasing sequentially to perform multi-grade screening of the raw coal, resulting in coal blocks of different grades. Then, a graded coal block conveying device transports the coal blocks of different grades to the graded stacking space in the coal bunker, achieving graded and zoned stacking of coal blocks. By grading and screening the raw coal at the source and separating the coal for separate disposal, it avoids the mixing and stacking of coal blocks of different particle sizes, mutual compression and arching, and actively prevents bunker blockage and collapse accidents. It eliminates the need for dangerous passive unblocking methods, reducing operational safety risks.

[0017] In this invention, the multi-stage drum screen is a three-stage drum screen, consisting of a primary drum screen 3, a secondary drum screen 5, and a tertiary drum screen 7. The number of branch conveyor belts matches the number of drum screens. The feed end of each branch conveyor belt corresponds to the discharge port of one drum screen, and the discharge end extends to the corresponding area above the coal bunker opening, used to transport coal blocks of different gradations to the coal bunker 0 respectively. Figure 1 As shown, a graded accumulation area is formed vertically within coal bunker 0: The central cylindrical area, located at the center of the coal bunker, is the central cylindrical area 14 of the coal bunker where small-particle graded coal blocks are piled up. It is formed by the small-particle graded coal blocks being transported by the branch conveyor belt 4 of the primary drum screen. The middle annular area, surrounding the outer side of the central cylindrical area, is the middle annular area 13 of the coal bunker where medium-sized coal blocks are piled up. It is formed by the accumulation of medium-sized coal blocks conveyed by the secondary drum screen branch conveyor belt 6. The outer ring area, surrounding the middle ring area, is the outer ring area 12 of the coal bunker where large-particle graded coal blocks are piled up. It is formed by the large-particle graded coal blocks being transported by the branch conveyor belt 8 of the three-stage drum screen.

[0018] This technical solution employs a three-stage drum screen structure, with primary, secondary, and tertiary drum screens sequentially installed along the raw coal conveying direction. This three-stage progressive screening achieves refined grading of the raw coal. The three-stage grading and screening structure is adapted to the particle size distribution characteristics of raw coal in coal mines, enabling more precise separation of coal lumps of different sizes, providing a precise grading basis for subsequent zoned stockpiling.

[0019] In this invention, the primary drum screen 3 has a screen aperture of 100mm, used to screen out small coal particles with a particle size ≤100mm; the secondary drum screen 5 has a screen aperture of 300mm, used to screen out medium-sized coal particles with a particle size of 100-300mm; and the tertiary drum screen 7 has a screen aperture of 500mm, used to screen out large coal particles with a particle size of 300-500mm, thus achieving precise particle size classification of raw coal. Clear particle size classification standards ensure accurate separation of coal particles of different grades, providing a guarantee for the graded stacking structure of "small particles in the center - medium particles in the middle - large particles on the outer layer" within the coal bunker 0, further optimizing the flowability of coal particles within the coal bunker 0.

[0020] This invention also includes: The four-stage drum screen, with a screen aperture size >500mm, is used to screen out extra-large coal particles with a particle size >500mm. The feed end of the grading coal conveying device corresponding to the fourth-stage drum screen is equipped with a crusher to crush oversized coal particles to ≤500mm before feeding them back to the third-stage drum screen. If a fourth-stage drum screen is installed, an outermost circular area is added to the coal bunker 0 to accumulate oversized graded coal particles. The fourth-stage drum screen is specifically designed to handle oversized coal particles, avoiding local blockages or uneven accumulation caused by their direct entry into the coal bunker 0. Simultaneously, the crushing and feeding back process achieves efficient resource utilization and improves the system's adaptability to complex raw coal.

[0021] In this invention, the discharge end of the graded coal block conveying device is equipped with a guiding device. The coal blocks are conveyed via the guiding device to a reversible distribution belt conveyor located at the entrance of the underground coal bunker 0. The reversible distribution belt conveyor then transports the coal blocks into the coal bunker 0. Through the cooperation of the guiding device and the reversible distribution belt conveyor, precise connection between the graded conveying and the coal falling into the coal bunker 0 is achieved, preventing the coal blocks from deviating from the preset path during the conveying process and ensuring the accuracy of graded zone coal falling.

[0022] In this invention, the reversible batching conveyor belt is equipped with bidirectional moving wheels, allowing it to move in both directions and unload screened coal blocks at multiple points. This is used to precisely control the dropping position and speed of coal blocks of different grades, ensuring that the coal blocks are piled up in preset zones within the coal bunker 0, avoiding cross-zone mixing. Preferably, the reversible batching conveyor belt is equipped with two ring zones: an outer ring zone 12 for large-particle-grade coal blocks and a middle ring zone 13 for medium-particle-grade coal blocks, respectively installed at the bottom of the coal bunker 0. The corresponding reversible batching conveyor belts are a reversible batching conveyor belt 10 for transporting large-particle-grade coal blocks and a reversible batching conveyor belt 11 for transporting medium-particle-grade coal blocks.

[0023] In this invention, the multi-stage drum screen also includes an anti-clogging and cleaning mechanism installed inside it. This mechanism is an elastic scraper that rotates synchronously with the drum screen, cleaning coal lumps adhering to the screen holes in real time. This effectively prevents the screen holes from being blocked by coal lumps, ensuring the screening efficiency and stability of the drum screen, reducing production downtime caused by screen hole blockage, and lowering the frequency of equipment maintenance.

[0024] In this invention, a buffer transition plate 2 is provided between the coal conveying device and the multi-stage drum screen to buffer the impact of coal blocks and guide them to enter the drum screen evenly, so as to avoid the impact of raw coal causing a decrease in screening efficiency, protect the screening equipment, and avoid screen hole blockage and component wear. The inclination angle of the buffer transition plate 2 is 15-30°.

[0025] In this invention, the inner wall of the coal bunker 0 is provided with an impact-resistant, wear-resistant, and smooth lining layer 9 of ultra-high molecular weight polyethylene plastic sheet, which is used to reduce the friction between coal blocks (including coal gangue and sticky mixtures) and the bunker wall, so that the coal blocks flow smoothly without sticking or accumulating, and avoid the formation of caking and blockage due to coal blocks sticking to the wall and compacting.

[0026] In this invention, the coal bunker 0 is equipped with a bunker level monitoring sensor to monitor the height distribution of each section within the bunker in real time, and the sensor is connected to the ground control system. This enables real-time monitoring of the coal accumulation within the bunker 0. When the coal level in a certain section reaches a preset threshold, the control system can intelligently adjust the flow rate of the corresponding branch conveyor belt to prevent coal overflow, ensure the stability of coal accumulation within the bunker 0, and improve the system's intelligence level.

[0027] In this invention, each multi-stage drum screen has a drive motor, a speed regulator, and an anti-clogging cleaning mechanism. The speed regulator adjusts the rotational speed of the drum screen as follows:

[0028] in The rotational speed (r / min) of the drum screen. The filling coefficient for the main coal conveyor belt 1 is 0.6~0.8. The speed of the main coal conveyor belt is 1 (m / s). The filling coefficient for the drum screen is 0.3~0.5. The diameter (m) of the drum screen is used to adapt to the screening requirements of different raw coals.

[0029] In this invention, the conveying speed of the branch conveyor belt is:

[0030] in The speed of the branch conveyor belt (m / s) The rotational speed (r / min) of the drum screen. The filling coefficient for the drum screen is 0.3~0.5. The diameter of the drum screen is (m). The filling coefficient of the branch conveyor belt is 0.6~0.8 to ensure the transportation efficiency required for continuous coal mine production and avoid raw coal accumulation due to excessively slow speed. The frame of the branch conveyor belt adopts a telescopic and adjustable structure, which can flexibly adjust the horizontal distance of the discharge end according to the diameter of the coal bunker and the horizontal position requirements of different coal dropping zones. This ensures that each belt is accurately aligned with the preset zone, avoids coal blocks falling into the wrong area, and ensures that the "gradation zone" does not fail.

[0031] The technical solution of the present invention will be clearly and thoroughly described below with reference to specific embodiments.

[0032] Example 1 This embodiment employs an anti-clogging bin system with a three-stage drum screen. The components are described below: Main coal conveyor belt 1: The belt conveyor commonly used in existing coal mines is used, with a belt width of 1.2m and a conveying speed of 2.5m / s. It is set between the working face and the coal bunker opening.

[0033] Multi-stage drum screens: Three drum screens are installed sequentially near the coal bunker 0 along the conveying direction of the main coal conveyor belt 1, with a spacing of 15m. Specific parameters: Primary drum screen 3: 800mm in diameter, 5m in length, 100mm in screen aperture (screens out small coal particles with a diameter ≤100mm). Secondary drum screen 5: 800mm in diameter, 5m in length, 300mm in screen aperture (screens out medium-sized coal lumps with a particle size of 100-300mm). Three-stage drum screen 7: 800mm in diameter, 5m in length, 500mm in screen aperture (screens out large coal particles with a diameter of 300-500mm); Each drum screen is equipped with a drive motor, speed regulator and elastic scraper.

[0034] Branch conveyor belts: 3 DTⅡ type belt conveyors, each with a width of 0.8m and a conveying speed of 2m / s. The feed ends correspond to the discharge ports of the 3 drum screens, and the discharge ends extend above the coal bunker opening. The first branch conveyor belt (corresponding to the first-stage drum screen 3): the discharge end is located directly above the 0 axis of the coal bunker, 3m above the coal bunker opening; The second branch conveyor belt (corresponding to the secondary drum screen 5): the discharge end is located 1.5m outside the 0 axis of the coal bunker, and 3m above the coal bunker opening; The third branch conveyor belt (corresponding to the third-stage drum screen 7): the discharge end is located 2.5m outside the 0 axis of the coal bunker, and 3m above the coal bunker opening; Each branch conveyor belt discharge end is equipped with an electric flow controller.

[0035] Coal Bunker 0: 6m in diameter, 25m in height. The bunker walls are lined with a wear-resistant and smooth lining layer 9 (15mm thick) made of impact-resistant ultra-high molecular weight polyethylene plastic sheet. Three bunker position monitoring sensors are installed inside the bunker (corresponding to the central cylindrical area 14 of the coal bunker with small particle size coal blocks, the middle annular area 13 of the coal bunker with medium particle size coal blocks, and the outer annular area 12 of the coal bunker with large particle size coal blocks), and are connected to the ground PLC control system.

[0036] Graded accumulation area: The outer ring area 12 of the coal bunker with large-particle-graded coal blocks: with a radius of 1m, is filled with small-particle coal blocks (≤100mm). The middle circular area 13 of the coal bunker where medium-sized coal blocks are piled up: inner radius 1m, outer radius 2m, piled up medium-sized coal blocks (100-300mm). The central cylindrical area 14 of the coal bunker is composed of small-particle-grade coal blocks with an inner radius of 2m and an outer radius of 3m, and contains large-particle coal blocks (300-500mm).

[0037] The work process is as follows: Raw coal conveying: The raw coal mined from the working face is conveyed to the multi-stage drum screen area via the main coal conveyor belt 1, and then smoothly enters the first-stage drum screen 3 via the buffer transition plate 2; Grading and screening: The primary drum screen separates small coal particles, which are then transported via the primary drum screen branch conveyor belt 4 to the central cylindrical area 14 of the coal bunker where small-particle graded coal particles are piled up; the raw coal that does not pass through the primary drum screen enters the secondary drum screen 5, which separates medium-particle coal particles, and is then transported via the secondary drum screen branch conveyor belt 6 to the central annular area 13 of the coal bunker where medium-particle graded coal particles are piled up; the raw coal that does not pass through the secondary drum screen enters the tertiary drum screen 7, which separates large coal particles, and is then transported via the tertiary drum screen branch conveyor belt 8 to the outer annular area 12 of the coal bunker where large-particle graded coal particles are piled up.

[0038] Intelligent monitoring and control: The ground control system obtains the height distribution of each zone's silos in real time through silo monitoring sensors. When a zone's silos reach 80% capacity, the flow controller of the corresponding branch conveyor belt is adjusted to reduce the amount of coal falling. When the silos reach 90% capacity, the corresponding branch conveyor belt is suspended to ensure stable coal accumulation within the coal silo and prevent overflow.

[0039] Example 2 Based on Example 1, a fourth-stage drum screen is added, as follows: The fourth-stage drum screen is installed behind the third-stage drum screen, with a spacing of 15m, a diameter of 800mm, a length of 5m, and a screen aperture size of 1000mm (to screen out oversized coal particles with a diameter >500mm). A branch conveyor belt for the fourth-stage drum screen is added accordingly. A small crusher is installed at the feed end of the branch conveyor belt for the fourth-stage drum screen, which can crush the oversized coal particles to ≤500mm and then return them to the third-stage drum screen. Subsequently, they are transported from the branch conveyor belt 8 of the third-stage drum screen to the outermost circular area of ​​the coal bunker for storage.

[0040] The work process is as follows: Raw coal conveying: The raw coal mined from the working face is conveyed to the multi-stage drum screen area via the main coal conveyor belt 1, and then smoothly enters the first-stage drum screen 3 via the buffer transition plate 2; Grading and screening: The primary drum screen separates small coal particles, which are then conveyed via the primary drum screen branch conveyor belt 4 to the central cylindrical area 14 of the coal bunker where small-particle graded coal particles are piled up; the raw coal that does not pass through the primary drum screen enters the secondary drum screen 5, which separates medium-sized coal particles, and is then conveyed via the secondary drum screen branch conveyor belt 6 to the central annular area 13 of the coal bunker where medium-particle graded coal particles are piled up; the raw coal that does not pass through the secondary drum screen enters the tertiary drum screen 7, which separates large coal particles, and is then conveyed via the tertiary drum screen branch conveyor belt 8 to the outer annular area 12 of the coal bunker where large-particle graded coal particles are piled up; the extra-large coal particles that do not pass through the tertiary drum screen are screened by the quaternary drum screen and then crushed by a small crusher, and then returned to the tertiary drum screen, and conveyed via the tertiary drum screen branch conveyor belt 8 to the outermost annular area of ​​the coal bunker for storage.

[0041] Intelligent monitoring and control: The ground control system obtains the height distribution of each zone in real time through sensors in the silo. When the silo of a certain zone reaches 80%, the flow controller of the corresponding branch belt is adjusted to reduce the amount of coal falling; when the silo reaches 90%, the conveying of the corresponding branch belt is suspended to ensure the stable accumulation of coal blocks in the coal silo and avoid overflow.

[0042] The above description is merely a preferred embodiment of the present invention. However, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the scope of protection of the present invention.

Claims

1. An active anti-blocking system for graded and zoned coal falling in underground coal bunkers of coal mines, characterized in that, include: Coal conveying equipment, used to transport raw coal mined from the working face; Multi-stage drum screens are arranged sequentially along the conveying direction of the main coal conveyor belt. The screen aperture size of each stage of the drum screen increases sequentially along the conveying direction of the raw coal. They are used to perform multi-stage screening of the raw coal to obtain coal blocks of different grades. A graded coal conveying device is used to transport coal blocks of different grades to the coal bunker separately. The coal bunker has tiered stacking spaces for stacking coal blocks of different grades.

2. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 1, characterized in that, The multi-stage drum screen is a three-stage drum screen, consisting of a primary drum screen, a secondary drum screen, and a tertiary drum screen.

3. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 2, characterized in that, The primary drum screen is used to screen out small coal particles with a diameter ≤100mm; the secondary drum screen is used to screen out medium coal particles with a diameter of 100-300mm; and the tertiary drum screen is used to screen out large coal particles with a diameter of 300-500mm.

4. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 2, characterized in that, Also includes: The four-stage drum screen is used to screen out ultra-large coal particles with a particle size >500mm; The feed end of the graded coal block conveying device corresponding to the fourth-stage drum screen is equipped with a crusher, which is used to crush the oversized coal blocks to ≤500mm and then feed them back to the third-stage drum screen.

5. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 1, characterized in that, The discharge end of the graded coal block conveying device is equipped with a guiding device, and the coal blocks are conveyed through the guiding device to the reversible distribution belt conveyor set at the entrance of the underground coal bunker.

6. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 5, characterized in that, The reversible coal distribution conveyor is equipped with bidirectional moving wheels to ensure that the screened coal blocks are piled up in the corresponding pile area of ​​the coal bunker.

7. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 1, characterized in that, The multi-stage drum screen also includes an anti-clogging and cleaning mechanism installed on its inner side, which is an elastic scraper.

8. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 1, characterized in that, A buffer transition plate is provided between the coal conveying device and the multi-stage drum screen to buffer the impact of coal blocks and guide them into the drum screen.

9. The active anti-blocking system for graded and zoned coal falling in underground coal bunkers according to claim 1, characterized in that, The inner wall of the coal bunker is lined with an impact-resistant, wear-resistant, and smooth layer of ultra-high molecular weight polyethylene plastic sheet.

10. An active anti-blocking system for graded and zoned coal falling in underground coal bunkers in coal mines according to any one of claims 1-9, characterized in that, The coal bunker is equipped with bunker level monitoring sensors.

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