A gas control system and method for closed working face in high-gas coal seam

Abstract

The present invention discloses a gas control system and method for a closed working face in a high-gas coal seam. By changing the mining mode, the traditional mining mode of eliminating gas by ventilation is changed to a closed mining mode, and a sealing mechanism is used to seal the tunnels on both sides, so that the working face area is in a fully closed state. Due to the lack of external ventilation, the gas inside it continues to accumulate as the coal is mined, and the gas concentration greatly exceeds the gas explosion limit, thereby preventing the risks of coal spontaneous combustion, coal dust explosion and gas explosion; personnel cooperate in coal mining in the working cabin and the operating cabin, and transport the coal to the closed floor tunnel for storage, realizing a fully closed-loop process of coal mining, transportation and storage; through the coordinated operation of the gas concentration sensor and the filter, dynamic adjustment of the gas concentration and pressure in the working face is realized; in addition, the pressure relief drilling and microseismic monitoring sensors realize monitoring and early warning of gas outbursts and impact ground pressure in the working face, thereby effectively improving the efficiency of coal mining.

Description

Technical Field

[0001] The present invention relates to a gas control system and method for a closed working face in a high-gas coal seam, belonging to the technical field of coal and gas co-mining. Background Art

[0002] As coal mining goes deeper, the potential disasters faced during the mining process (such as gas, fire, flood, coal dust, roof accidents, etc.) are more serious, especially in deep high-gas outburst mines. When drilling into deep high-gas outburst coal seams, gas will continue to spew out from the boreholes, which can easily cause the gas in the tunnel to exceed the limit and become unable to continue working, which can easily cause accidents and restrict coal mine production. During the extraction process, due to the high gas pressure in the coal seam, the sealing effect of the extraction drill hole is not ideal, and it is easy to leak, which can also cause the gas in the tunnel to exceed the limit and cause accidents. Therefore, gas prevention and control in deep high-gas outburst mines has always been an industry problem that needs to be solved urgently.

[0003] Furthermore, the greenhouse effect of the same volume of gas (i.e., methane) is approximately 25 times greater than that of carbon dioxide. Since the concentration of extracted gas during current coal mining is low and cannot be effectively utilized, improving gas extraction efficiency requires extensive drilling into the coal seam. This increases production costs and, in turn, prolongs the time required to achieve gas extraction standards, hindering coal seam mining and replacement, which in turn affects coal production. Furthermore, ventilation systems are essential equipment in existing mines to protect the health of personnel within the working face and tunnels. They draw outside air into the mine and exhaust internal gases, completing the exchange process and maintaining air quality within the mine. However, during coal face mining, some gas inevitably enters the tunnels and is released into the outside environment through the ventilation system, resulting in both energy waste and environmental pollution. Furthermore, since the ventilation system allows oxygen from outside air to enter the goaf, it creates the necessary conditions for spontaneous coal combustion and gas and coal dust explosions, increasing the risk of mine disasters. Despite the long-term development and progress of existing coal mining technology, major disasters such as gas outbursts, gas explosions, and spontaneous coal combustion still occur frequently and are difficult to eradicate. Furthermore, with deeper mining, various disasters become more frequent and increasingly difficult to prevent and cure. The current mining system model makes it difficult to completely eliminate the impact of disasters. There is an urgent need to explore new methods and technologies for coal mining and gas extraction.

[0004] Therefore, for deep high-gas outburst mines, how to provide a new system and method to completely eradicate the risks of coal spontaneous combustion and gas explosion caused by gas, while monitoring and early warning of gas outbursts and impact ground pressure in the working face, improving the mine's coal mining efficiency, and effectively solving coal mine gas explosions, coal dust explosions, coal spontaneous combustion and other problems that have long plagued coal mine safety production, is the research direction of this industry. Summary of the Invention

[0005] In response to the problems existing in the above-mentioned prior art, the present invention provides a gas control system and method for a closed working face in a high-gas coal seam. The system can extract gas from the entire high-gas coal seam without ventilating the working face, and coal mining can be carried out at the same time as the extraction. This not only ensures the gas extraction efficiency, but also guarantees the coal mining volume. It effectively eliminates the hidden dangers of gas explosions while providing high-concentration, easily usable clean energy for subsequent gas extraction and utilization. It can also solve problems that have long plagued coal mine safety production, such as coal mine gas explosions, coal dust explosions, and coal spontaneous combustion.

[0006] In order to achieve the above-mentioned object, the technical solution adopted by the present invention is: a gas control system for a closed working face in a high-gas coal seam, comprising a closed isolation system, a personnel operation system, an intelligent production system, a gas extraction system, and a control and monitoring system;

[0007] The closed isolation system includes two sealing mechanisms, which are symmetrically arranged in the tunnels on both sides of the working face, and are used to separate and seal the tunnels, so that the working face area is in a fully closed state; the sealing mechanism includes a sealing wall 1, a sealing wall 2, a movable track and a refuge chamber, and the movable track is arranged on its bottom plate along the direction of the tunnel, and the sealing wall 1 and the sealing wall 2 are both installed on the movable track and can slide on the movable track; the sealing wall 1 and the sealing wall 2 are relatively fixed to the movable track by a locking mechanism, and the four sides of the sealing wall 1 and the four sides of the sealing wall 2 are sealed with the two side walls, bottom plate and top plate of the tunnel by sealing parts, so that a buffer zone is formed between the sealing wall 1 and the sealing wall 2, and the refuge chamber is installed in the buffer zone, and is respectively connected to the sealing wall 1 and the sealing wall 2 for personnel to take shelter; the sealing wall 1 and the sealing wall 2 are both provided with hatches;

[0008] The personnel operating system includes a working cabin, a guide rail and a plurality of hydraulic supports. The plurality of hydraulic supports are arranged side by side between the working face and the goaf and are used to support the working face after mining. The guide rail passes through each hydraulic support in sequence and is fixed relative to each hydraulic support. The working cabin is mounted on the guide rail and can slide on the guide rail, so that personnel can adjust and control the movement of each hydraulic support.

[0009] The intelligent production system includes a coal cutter, an operating cabin, and a scraper conveyor. The coal cutter is installed on the working surface. The operating cabin is fixedly connected to the coal cutter and is used to control the coal cutter to mine coal on the working surface. The cutting drum of the coal cutter is equipped with a temperature sensor and a coal cutter positioning sensor to monitor the temperature of the coal cutter during coal mining and the position of the coal cutter, and to feed back to the display screen in the operating cabin for display. One end of the scraper conveyor is located on the side of the coal cutter and the other end extends into the closed floor roadway, and is used to transport the mined coal to the closed floor roadway.

[0010] The gas extraction system includes an extraction pipe and a filter. One end of the extraction pipe extends from the outside of the tunnel through a sealing mechanism into the working face area. The other end of the extraction pipe is connected to a gas extraction pump station for extracting gas from the working face area. The filter is installed at one end of the extraction pipe for filtering impurities in the extracted gas.

[0011] The control and monitoring system includes a main control room, a control center, a gas concentration sensor, a temperature sensor, an air pressure sensor, and a microseismic monitoring sensor. The gas concentration sensor is installed at one end of the extraction pipe to monitor the real-time gas concentration of the extracted gas and provide feedback to the control center. The temperature sensor and air pressure sensor are both installed in the working face area to monitor the real-time temperature and air pressure of the working face area, respectively, and provide feedback to the control center. The microseismic monitoring sensor is installed around the working face to monitor the microseismic conditions during the working face mining process and provide feedback to the control center.

[0012] The main control room is arranged in a tunnel outside the working face area, and the control center is arranged in the main control room, which is used to receive data feedback from the gas concentration sensor, temperature sensor and air pressure sensor, and adjust the gas extraction flow after analyzing the data; the control center receives microseismic data feedback from the microseismic monitoring sensor, and after analyzing the data, determines the impact ground pressure hazard of the working face.

[0013] Furthermore, the working cabin is provided with a retractable ladder for personnel to enter and exit.

[0014] Furthermore, the hydraulic support is equipped with a hydraulic support positioning sensor for locating the position of the hydraulic support and feeding it back to the display screen inside the working cabin for display. This ensures that when the support needs to be moved, the corresponding hydraulic support can be directly positioned for moving operation.

[0015] Furthermore, the control center is a computer.

[0016] Furthermore, a belt conveyor is provided in the closed floor tunnel for transferring the coal transported by the scraper conveyor to a desired location for storage. In this way, after the mining is completed, the floor tunnel is opened to facilitate the subsequent transportation of the coal.

[0017] Furthermore, the sealing member is a sealing strip, which is convenient for installation and disassembly.

[0018] Furthermore, the locking mechanism is a locking bolt.

[0019] The working method of the gas control system for the closed working face in the high-gas coal seam is as follows:

[0020] A. Laying out the gas control system for the closed working face in high-gas coal seams: First, determine the working face to be mined, and open a floor lane below the roadway on one side of the working face. Seal the floor lane to form a closed floor lane to prevent outside air from entering. Then, lay out the various components of the gas control system for the closed working face in high-gas coal seams on the working face. Adjust the two sealing mechanisms to the required positions, secure them with the locking mechanism, and seal them with the two side walls, floor, and roof of the roadway using seals. This creates a buffer zone between the first and second sealing walls, and fully seals the working face area. Complete the system deployment.

[0021] B. Leak detection and gas extraction: Use a portable leak detector to check for leaks in both sealed mechanisms. If any leaks occur, they are immediately addressed until they are completely sealed. The control center then checks the readings of the air pressure sensor and gas concentration sensor. When the air pressure in the working face area exceeds the set threshold, the gas extraction pump station is activated and gas extraction is performed in the working face area through the extraction pipe. The air initially present in the working face area and the gas continuously desorbed from the coal seam are extracted. During the extraction process, the gas concentration sensor continuously collects real-time gas concentration values, and the air pressure sensor obtains real-time air pressure values ​​in the working face area.

[0022] C. Coal mining and hydraulic support operations: When the real-time gas concentration exceeds the upper limit of the gas explosion limit concentration and the air pressure in the working face area is within the set safety threshold range, the first group of mining workers are in the tunnel where the main control room is located. They first open the hatch of the enclosed wall 1 to enter the buffer zone and wear protective clothing in the buffer zone. After completion, they open the hatch of the enclosed wall 2 to enter the fully enclosed working face area until they enter the working cabin; start the working cabin and move it to the coal cutter. At this time, some mining workers leave the working cabin and enter the operating cabin, while the other part stays in the working cabin; the mining workers in the operating cabin The miner controls the coal cutter to start the coal mining operation and controls the scraper conveyor to transport the mined coal to the floor roadway. At the same time, the temperature during coal mining and the position of the coal cutter are known in real time through temperature sensors and coal cutter positioning sensors. The real-time position of the coal cutter is fed back to the miner in the working cabin. The miner in the working cabin positions each hydraulic support based on the real-time position of the coal cutter and the positioning sensors of each hydraulic support. When the coal cutter moves to the support range of the corresponding hydraulic support during coal mining, the miner controls the hydraulic support to move the support, thereby completing the coal mining and hydraulic support support operations.

[0023] D. Normal departure from the working face area and emergency evacuation: When the first group of mining workers reaches the working time, the mining workers in the operating cabin stop the coal cutter and work, leave the operating cabin and return to the working cabin, and then the working cabin moves to a position close to the entry position. The first group of mining workers all leave the working cabin and reach the sealing wall 2, and then first open the hatch of the sealing wall 2 to enter the buffer zone, and take off the protective clothing in the buffer zone. After completion, open the hatch of the sealing wall 1 to enter the tunnel outside the working face area to complete the normal departure process; the microseismic monitoring sensor monitors the microseismic conditions during the mining process of the working face in real time. If the control center analyzes the impact ground pressure risk exceeding the set value based on the microseismic monitoring data, the control center will communicate wirelessly with the working cabin and the mining workers in the operating cabin to send an early warning signal, so that the mining workers can return to the refuge in the buffer zone in time to take shelter, and then enter the tunnel from the buffer zone after the external environment stabilizes, completing the emergency evacuation process;

[0024] E. Continue to carry out gas co-mining: The second group of mining workers repeats steps C and D to continue coal mining and extracting high-concentration gas; the mining workers of subsequent groups continue to repeat to achieve the process of continuous gas co-mining; in the subsequent mining process, if each hydraulic support is moved, the position of the working cabin and the guide rail needs to be adjusted accordingly. At the same time, as the working face is mined, the position of the two sealing mechanisms also needs to be adjusted. The specific adjustment process is: first remove the seals around the sealing mechanism and loosen the locking mechanism. At this time, move the sealing mechanism along the moving track. After reaching the required position, fix the sealing mechanism with the locking mechanism. Finally, install seals around the sealing mechanism to complete the re-sealing of the working face area; leak detection is required after each re-sealing to ensure the sealing effect.

[0025] F. Temperature and pressure monitoring in the working face area: Gas extraction is carried out continuously throughout the coal mining process. Temperature sensors and pressure sensors monitor the real-time temperature and pressure of the working face area and feed them back to the control center. The control center analyzes the data and adjusts the power of the gas extraction pump station based on the real-time pressure value to keep the pressure in the working face area within the set threshold range. At the same time, the real-time temperature value fed back is compared with the set temperature threshold. If the set temperature threshold is exceeded, it indicates that there is a gas leak in the working face area, causing coal spontaneous combustion. In this case, the mining workers in the working face area are notified to evacuate in a timely manner.

[0026] G. Recycling of the device after the mining operation is completed: When the entire coal seam is mined, check the gas concentration shown by the gas concentration sensor. If the gas concentration exceeds the set standard, continue to perform gas extraction until the extracted gas concentration is lower than the set standard. Stop gas extraction, then recycle all detachable parts, close the entire mining area, and repeat steps A to G to enter the next working face for mining.

[0027] Furthermore, before the working face is mined, pressure relief boreholes are constructed in advance of the working face, thereby reducing the risk of rock burst during subsequent mining on the working face.

[0028] Compared with the existing technology, the present invention adopts a fully enclosed method for coal mining and gas extraction, which has the following advantages:

[0029] 1. The present invention fully seals the working face and goaf through a sealing mechanism to form a sealed space, thereby eliminating the existing ventilation system. Since no outside air enters the goaf and the coal mining working face, and by extracting the gas in the fully enclosed working face area, the internal oxygen is continuously reduced, and the gas in the coal seam is continuously desorbed into the working face area, so that the gas concentration in the enclosed area exceeds the upper explosion limit, and the working face area is continuously isolated from oxygen and the gas concentration is continuously higher than the upper explosion limit during the entire coal mining process, thereby fundamentally eliminating the risks of coal spontaneous combustion and gas and coal dust explosions.

[0030] 2. After the sealed space is formed, the present invention does not require the construction of gas extraction drilling holes for the entire high-gas coal seam, that is, the gas extraction compliance period is zero. The reason is that after the internal oxygen is extracted, the coal mining face is subsequently in an oxygen-isolated state, that is, there is no possibility of gas and coal dust explosion; thereby greatly accelerating the mining and replacement speed and reducing the construction cost of the mine. In addition, when subsequent coal mining is carried out in the sealed space, the desorbed gas is directly discharged into the coal mining face and the sealed space. Since the internal oxygen is extremely low, as the gas desorption continues, the gas concentration in the sealed space will continue to increase. At this time, the gas is extracted through the gas extraction pump station, which greatly improves the gas utilization rate; in addition, since it is a fully enclosed environment, all the desorbed gas enters the gas extraction pump station for extraction and will not be discharged into the atmosphere, which reduces the impact of gas on the greenhouse effect and is environmentally friendly; thereby achieving gas extraction of the entire high-gas coal seam, and coal mining can be carried out while extraction is taking place, which not only ensures the gas extraction efficiency, but also guarantees the coal mining volume.

[0031] 3. In the present invention, the mining workers enter the working cabin and the operating cabin respectively. The personnel in the working cabin controls the hydraulic support, and the personnel in the operating cabin controls the coal cutter to mine coal. Wireless communication between the two is used for coordinated control, so that the hydraulic support can provide corresponding support as the coal cutter mines, ensuring mining safety and ultimately realizing the coal gas co-mining process. The extracted gas has a high concentration, which is convenient for subsequent direct use.

[0032] 4. The present invention monitors the real-time temperature and air pressure of the working face area through temperature sensors and air pressure sensors respectively, adjusts the power of the gas extraction pump station according to the real-time air pressure value, so that the air pressure in the working face area is maintained within the set safety threshold range, and at the same time judges whether there is a gas leakage inside the working face area that causes coal spontaneous combustion based on the feedback real-time temperature value. If such a situation occurs, the mining workers in the working face area can be notified in time to evacuate; in addition, microseismic monitoring sensors are used to monitor the microseismic conditions during the working face mining process in real time. If impact ground pressure occurs, the mining workers can be notified in time to return to the refuge cabin in the buffer zone in time to avoid it, thereby ensuring the safety of personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall layout of the present invention.

[0034] In the figure: 1-main control room, 2-control center, 3-cabin door, 4-sealing mechanism, 5-buffer zone, 6-refuge chamber, 7-mobile track, 8-tunnel, 9-microseismic monitoring sensor, 10-retractable ladder, 11-pressure relief drilling hole, 12-working cabin, 13-hydraulic support, 14-hydraulic support positioning sensor, 15-goaf, 16-spray dust suppression device, 17-coal cutter positioning sensor, 18-operating cabin, 19-coal cutter, 20-guide rail, 21-temperature sensor, 22-air pressure sensor, 23-scraper conveyor, 24-gas concentration sensor, 25-enclosed bottom plate tunnel, 26-filter, 27-extraction pipe, 28-belt conveyor. DETAILED DESCRIPTION

[0035] The present invention will be further described below.

[0036] like Figure 1 As shown, a gas control system for a closed working face in a high-gas coal seam includes a closed isolation system, a personnel operation system, an intelligent production system, a gas extraction system, and a control and monitoring system;

[0037] The closed isolation system includes two sealing mechanisms 4, which are symmetrically arranged in the tunnels 8 on both sides of the working face, and are used to separate and seal the tunnels 8 so that the working face area is in a fully closed state; the sealing mechanism 4 includes a sealing wall 1, a sealing wall 2, a movable track 7 and a refuge chamber 6, and the movable track 7 is arranged on the bottom plate of the tunnel 8. The sealing wall 1 and the sealing wall 2 are both installed on the movable track 7 and can slide on the movable track 7; the sealing wall 1 and the sealing wall 2 are relatively fixed to the movable track 7 by a locking mechanism, and the locking mechanism is a locking bolt or other existing mechanism with the same function. The four sides of the first and second closed walls are sealed with the two side walls, bottom plate and top plate of the tunnel 8 by seals, so that a buffer zone 5 is formed between the first and second closed walls. The seals are sealing strips or other existing mechanisms with the same function, which are easy to install and remove. The refuge chamber 6 is installed in the buffer zone 5 and is connected to the first and second closed walls respectively for personnel to take shelter. The first and second closed walls are both provided with hatches 3.

[0038] The personnel operating system includes a working cabin 12, a guide rail 20 and a plurality of hydraulic supports 13. The plurality of hydraulic supports 13 are arranged side by side between the working face and the goaf 15 for supporting the working face after excavation. The guide rail 20 passes through each hydraulic support 13 in sequence and is fixed relative to each hydraulic support 13. The working cabin 12 is mounted on the guide rail 20 and can slide on the guide rail 20 for personnel to control the movement of each hydraulic support 13. The working cabin 12 is provided with a retractable ladder 10 for personnel to enter and exit. The hydraulic support 13 is equipped with a hydraulic support positioning sensor 14 for locating the position of the hydraulic support 13 and feeding it back to the display screen inside the working cabin 12 for display. This ensures that when the frame needs to be moved, the corresponding hydraulic support 13 can be directly located for the frame moving operation.

[0039] The intelligent production system includes a coal cutter 19, an operating cabin 18 and a scraper conveyor 23. The coal cutter 19 is installed on the working surface. The operating cabin 18 is fixedly connected to the coal cutter 19 and is used to control the coal cutter 19 to mine coal on the working surface. The cutting drum of the coal cutter 19 is equipped with a temperature sensor and a coal cutter positioning sensor 17, which are used to monitor the temperature of the coal cutter 19 during coal mining and the position of the coal cutter 19, and feed back to the display screen in the operating cabin 18 for display; one end of the scraper conveyor 23 is located on the side of the coal cutter 19 and the other end extends into the closed floor lane 25, which is used to transport the mined coal to the closed floor lane 25; a belt conveyor 28 is provided in the closed floor lane 25, which is used to transfer the coal transported by the scraper conveyor 23 to the required location for storage. In this arrangement, during coal mining, the closed floor tunnel 25 and the working face area together form a fully enclosed area. In this way, when the scraper conveyor 23 transfers the coal to the closed floor tunnel 25, since the closed floor tunnel 25 is in a closed state, the desorbed gas can be extracted and utilized during the process of transporting the coal from the working face area to the floor tunnel 25 and when the coal is accumulated in the floor tunnel 25. In addition, since the floor tunnel is isolated from the outside world, the oxygen content is extremely low, thereby reducing the possibility of oxidation reaction during coal storage and ensuring the coal storage effect. In addition, after the subsequent working face completes coal mining, the closed floor tunnel 25 is opened to carry out subsequent transportation of the coal.

[0040] The gas extraction system includes an extraction pipe 27 and a filter 26. One end of the extraction pipe 27 extends from the outside of the tunnel through the sealing mechanism 4 into the working face area. The other end of the extraction pipe 27 is connected to the gas extraction pump station for extracting gas from the working face area. The filter 26 is installed at one end of the extraction pipe 27 for filtering impurities in the extracted gas.

[0041] The control and monitoring system includes a main control room 1, a control center 2, a gas concentration sensor 24, a temperature sensor 21, an air pressure sensor 22, and a microseismic monitoring sensor 9. The control center 2 is a computer. The gas concentration sensor 24 is installed at one end of the extraction pipe 27 to monitor the real-time gas concentration of the extracted gas and provide feedback to the control center 2. The temperature sensor 21 and the air pressure sensor 22 are both installed in the working face area to monitor the real-time temperature and air pressure of the working face area, respectively, and provide feedback to the control center 2. The microseismic monitoring sensor 9 is installed around the working face to monitor microseismic conditions during the working face mining process and provide feedback to the control center 2.

[0042] The main control room 1 is arranged in the tunnel 8 outside the working face area, and the control center 2 is arranged in the main control room 1, which is used to receive data fed back by the gas concentration sensor 24, the temperature sensor 21 and the air pressure sensor 22, and adjust the gas extraction flow after analyzing the data; the control center 2 receives the microseismic data fed back by the microseismic monitoring sensor 9, and after analyzing the data, determines the impact ground pressure hazard of the working face.

[0043] The above-mentioned locking mechanism, seals, refuge chamber 6, hydraulic support 13, working cabin 12, coal cutter 19, operating cabin 18, scraper conveyor 23, temperature sensor, coal cutter positioning sensor 17, belt conveyor 28, filter 26, gas extraction pump station, control center 2, gas concentration sensor 24, temperature sensor 21, protective clothing, air pressure sensor 22 and microseismic monitoring sensor 9 are all existing components or equipment and can be purchased on the market.

[0044] The working method of the gas control system for the closed working face in the high-gas coal seam is as follows:

[0045] A. Laying out a gas control system for a closed working face in a high-gas coal seam: first determine the working face to be mined, and open a floor lane below the roadway 8 on one side of the working face. The floor lane is sealed to form a closed floor lane 25 to prevent outside air from entering the floor lane. The floor lane is used to store coal mined from the working face. No personnel are allowed inside the floor lane during coal mining. Then, various parts of the gas control system for a closed working face in a high-gas coal seam are laid out on the working face. The two sealing mechanisms 4 are adjusted to the desired positions, fixed by a locking mechanism, and sealed with the two side walls, floor, and roof of the roadway 8 by sealing members, so that a buffer zone 5 is formed between the sealing wall 1 and the sealing wall 2, and the working face area is in a fully enclosed state. The system is laid out. If needed, a spray dust suppression device 16 can be added next to the working face to reduce dust during the mining process.

[0046] B. Detect leaks and perform gas extraction: Use a portable leak detector to check the two sealed mechanisms 4 for leaks. If there is a leak, immediately deal with it until it is completely sealed; then, check the readings of the air pressure sensor 22 and the gas concentration sensor 24 through the control center 2. When the air pressure in the working face area exceeds the set threshold (the gas continuously desorbed in the coal seam enters the working face area, which will increase its air pressure), start the gas extraction pump station and extract gas from the working face area through the extraction pipe 27 to extract the air initially present in the working face area and the gas continuously desorbed from the coal seam. During the extraction process, the real-time gas concentration value is continuously collected by the gas concentration sensor 24; since the working face area is in a fully enclosed state, the air content continues to decrease as the extraction continues, while the gas desorbed from the coal seam continues to increase, resulting in a continuous increase in the gas concentration in the extracted gas, thereby ensuring the efficiency of gas extraction.

[0047] C. Coal mining and hydraulic support support operations: When the real-time gas concentration value exceeds the upper limit of the gas explosion limit concentration and the air pressure in the working face area is within the set safety threshold range, the first group of mining workers are in the tunnel 8 where the main control room 1 is located. They first open the hatch 3 of the enclosed wall 1 to enter the buffer zone 5 and wear protective clothing in the buffer zone. After completion, they open the hatch 3 of the enclosed wall 2 to enter the fully enclosed working face area until they enter the working cabin 12; start the working cabin 12 and move it to the coal cutter 19. At this time, some mining workers leave the working cabin 12 and enter the operating cabin 18, while the other part stays in the working cabin 12; the mining workers in the operating cabin 18 control The coal cutter 19 begins coal mining and simultaneously controls the scraper conveyor 23 to transport the mined coal to the floor roadway 25. Simultaneously, the temperature of the coal during mining and the position of the coal cutter 19 are known in real time through the temperature sensor and the coal cutter positioning sensor 17. The real-time position of the coal cutter 19 is fed back to the miners in the working cabin 12. Based on the real-time position of the coal cutter 19 and the positioning of each hydraulic support 13 by the positioning sensors of each hydraulic support 13, the miners in the working cabin 12 control the hydraulic support 13 to move when the coal cutter 19 moves to the support range of the corresponding hydraulic support 13 during coal mining, thereby completing the coal mining and hydraulic support support operations.

[0048] D. Normal departure from the working face area and emergency evacuation: When the first group of mining workers reaches the working time, the mining workers in the operating cabin 18 stop the coal cutter 19 and work, and leave the operating cabin 18 and return to the working cabin 12, and then the working cabin 12 moves to a position close to the entry position. The first group of mining workers all leave the working cabin 12 and reach the sealing wall 2, and then first open the hatch 3 of the sealing wall 2 to enter the buffer zone 5, and take off the protective clothing in the buffer zone 5. After completion, open the hatch of the sealing wall 1 to enter the tunnel 8 outside the working face area, and complete the normal departure process; the microseismic monitoring sensor 9 monitors the microseismic conditions of the working face mining process in real time. If the control center 2 analyzes the impact ground pressure risk exceeding the set value based on the microseismic monitoring data, the control center 2 communicates wirelessly with the mining workers in the working cabin 12 and the operating cabin 18 to send an early warning signal, so that the mining workers can return to the refuge chamber 6 in the buffer zone 5 in time to take shelter, and enter the tunnel 8 from the buffer zone 5 after the external environment stabilizes, completing the emergency evacuation process;

[0049] E. Continue to carry out gas co-mining: The second group of mining workers repeats steps C and D to continue coal mining and extracting high-concentration gas; the mining workers of each subsequent group continue to repeat to realize the process of continuous gas co-mining; in the subsequent mining process, after each hydraulic support 13 is moved, the position of the working cabin 12 and the guide rail 20 needs to be adjusted accordingly. At the same time, as the working face is mined, the position of the two sealing mechanisms 4 also needs to be adjusted. The specific adjustment process is: first remove the seals around the sealing mechanism 4 and release the locking mechanism. At this time, the sealing mechanism is moved along the movable track 7. After reaching the desired position, the locking mechanism fixes the sealing mechanism. Finally, seals are installed around the sealing mechanism 4 to complete the re-sealing of the working face area; leak detection is required after each re-sealing to ensure the sealing effect.

[0050] F. Monitoring of temperature and air pressure in the working face area: During the entire coal mining process, gas extraction operations are continuously carried out. The temperature sensor 21 and the air pressure sensor 22 respectively monitor the real-time temperature and air pressure of the working face area and feed them back to the control center 2. The control center 2 analyzes the data and adjusts the power of the gas extraction pump station according to the real-time air pressure value to keep the air pressure in the working face area within the set safety threshold. At the same time, the real-time temperature value fed back is compared with the set temperature threshold. If the set temperature threshold is exceeded, it indicates that there is a gas leak in the working face area, causing coal spontaneous combustion. In this case, the mining workers in the working face area are promptly notified to evacuate.

[0051] G. Recycling of the device after the mining operation is completed: When the entire coal seam is mined, check the gas concentration shown by the gas concentration sensor 24. If the gas concentration exceeds the set standard, continue to perform gas extraction until the extracted gas concentration is lower than the set standard. Stop gas extraction, then recycle all detachable parts, close the entire mining area, and repeat steps A to G to enter the next working face for mining.

[0052] As an improvement of the present invention, before the working face is mined, a pressure relief borehole 11 is constructed in advance toward the working face, thereby reducing the risk of rock burst during subsequent mining at the working face.

[0053] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A closed working face gas control system for high-gas coal seams, characterized in that: Including closed isolation system, personnel operation system, intelligent production system, gas extraction system and control and monitoring system; The closed isolation system includes two sealing mechanisms, which are symmetrically arranged in the tunnels on both sides of the working face, and are used to separate and seal the tunnels, so that the working face area is in a fully closed state; the sealing mechanism includes a sealing wall 1, a sealing wall 2, a movable track and a refuge chamber, and the movable track is arranged on its bottom plate along the direction of the tunnel, and the sealing wall 1 and the sealing wall 2 are both installed on the movable track and can slide on the movable track; the sealing wall 1 and the sealing wall 2 are relatively fixed to the movable track by a locking mechanism, and the four sides of the sealing wall 1 and the four sides of the sealing wall 2 are sealed with the two side walls, bottom plate and top plate of the tunnel by sealing parts, so that a buffer zone is formed between the sealing wall 1 and the sealing wall 2, and the refuge chamber is installed in the buffer zone, and is respectively connected to the sealing wall 1 and the sealing wall 2 for personnel to take shelter; the sealing wall 1 and the sealing wall 2 are both provided with hatches; The personnel operating system includes a working cabin, a guide rail and a plurality of hydraulic supports. The plurality of hydraulic supports are arranged side by side between the working face and the goaf and are used to support the working face after mining. The guide rail passes through each hydraulic support in sequence and is fixed relative to each hydraulic support. The working cabin is mounted on the guide rail and can slide on the guide rail, so that personnel can adjust and control the movement of each hydraulic support. The intelligent production system includes a coal cutter, an operating cabin, and a scraper conveyor. The coal cutter is installed on the working surface. The operating cabin is fixedly connected to the coal cutter and is used to control the coal cutter to mine coal on the working surface. The cutting drum of the coal cutter is equipped with a temperature sensor and a coal cutter positioning sensor to monitor the temperature of the coal cutter during coal mining and the position of the coal cutter, and to feed back to the display screen in the operating cabin for display. One end of the scraper conveyor is located on the side of the coal cutter and the other end extends into the closed floor roadway, and is used to transport the mined coal to the closed floor roadway. The gas extraction system includes an extraction pipe and a filter. One end of the extraction pipe extends from the outside of the tunnel through a sealing mechanism into the working face area. The other end of the extraction pipe is connected to a gas extraction pump station for extracting gas from the working face area. The filter is installed at one end of the extraction pipe for filtering impurities in the extracted gas. The control and monitoring system includes a main control room, a control center, a gas concentration sensor, a temperature sensor, an air pressure sensor, and a microseismic monitoring sensor. The gas concentration sensor is installed at one end of the extraction pipe to monitor the real-time gas concentration of the extracted gas and provide feedback to the control center. The temperature sensor and air pressure sensor are both installed in the working face area to monitor the real-time temperature and air pressure of the working face area, respectively, and provide feedback to the control center. The microseismic monitoring sensor is installed around the working face to monitor the microseismic conditions during the working face mining process and provide feedback to the control center. The main control room is arranged in a tunnel outside the working face area, and the control center is arranged in the main control room, which is used to receive data feedback from the gas concentration sensor, temperature sensor and air pressure sensor, and adjust the gas extraction flow after analyzing the data; the control center receives microseismic data feedback from the microseismic monitoring sensor, and after analyzing the data, determines the impact ground pressure hazard of the working face.

2. The closed working face gas control system for high-gas coal seams according to claim 1, characterized in that: The working cabin is provided with a retractable ladder for personnel to enter and exit.

3. The closed working face gas control system for high-gas coal seams according to claim 1, characterized in that: The hydraulic support is equipped with a hydraulic support positioning sensor for locating the position of the hydraulic support and feeding back the position to a display screen inside the working cabin for display.

4. The closed working face gas control system for high-gas coal seams according to claim 1, characterized in that: The control center is a computer.

5. The closed working face gas control system for high-gas coal seams according to claim 1 is characterized in that: A belt conveyor is provided in the closed floor tunnel for transferring the coal transported by the scraper conveyor to a desired location for storage.

6. The closed working face gas control system for high-gas coal seams according to claim 1, characterized in that: The sealing member is a sealing strip.

7. The closed working face gas control system for high-gas coal seams according to claim 1, characterized in that: The locking mechanism is a locking bolt.

8. A method for operating a closed working face gas control system for a high-gas coal seam according to any one of claims 1 to 7, characterized in that: The specific steps are: A. Laying out the gas control system for the closed working face in high-gas coal seams: First, determine the working face to be mined, and open a floor laneway below the roadway on one side of the working face. Seal the floor laneway to form a closed floor laneway. Then, lay out the various components of the gas control system for the closed working face in high-gas coal seams on the working face. Adjust the two sealing mechanisms to the required positions, secure them with the locking mechanism, and seal them with the two side walls, floor, and roof of the roadway using seals. This creates a buffer zone between the first and second sealing walls, and fully seals the working face area. Complete the system deployment. B. Leak detection and gas extraction: Use a portable leak detector to check for leaks in both sealed mechanisms. If any leaks occur, they are immediately addressed until they are completely sealed. The control center then checks the readings of the air pressure sensor and gas concentration sensor. When the air pressure in the working face area exceeds the set threshold, the gas extraction pump station is activated and gas extraction is performed in the working face area through the extraction pipe. The air initially present in the working face area and the gas continuously desorbed from the coal seam are extracted. During the extraction process, the gas concentration sensor continuously collects real-time gas concentration values, and the air pressure sensor obtains real-time air pressure values ​​in the working face area. C. Coal mining and hydraulic support operations: When the real-time gas concentration exceeds the upper limit of the gas explosion limit concentration and the air pressure in the working face area is within the set safety threshold range, the first group of mining workers are in the tunnel where the main control room is located. They first open the hatch of the enclosed wall 1 to enter the buffer zone and wear protective clothing in the buffer zone. After completion, they open the hatch of the enclosed wall 2 to enter the fully enclosed working face area until they enter the working cabin; start the working cabin and move it to the coal cutter. At this time, some mining workers leave the working cabin and enter the operating cabin, while the other part stays in the working cabin; the mining workers in the operating cabin The miner controls the coal cutter to start the coal mining operation and controls the scraper conveyor to transport the mined coal to the floor roadway. At the same time, the temperature during coal mining and the position of the coal cutter are known in real time through temperature sensors and coal cutter positioning sensors. The real-time position of the coal cutter is fed back to the miner in the working cabin. The miner in the working cabin positions each hydraulic support based on the real-time position of the coal cutter and the positioning sensors of each hydraulic support. When the coal cutter moves to the support range of the corresponding hydraulic support during coal mining, the miner controls the hydraulic support to move the support, thereby completing the coal mining and hydraulic support support operations. D. Normal departure from the working face area and emergency evacuation: When the first group of mining workers reaches the working time, the mining workers in the operating cabin stop the coal cutter and work, leave the operating cabin and return to the working cabin, and then the working cabin moves to a position close to the entry position. The first group of mining workers all leave the working cabin and reach the sealing wall 2, and then first open the hatch of the sealing wall 2 to enter the buffer zone, and take off the protective clothing in the buffer zone. After completion, open the hatch of the sealing wall 1 to enter the tunnel outside the working face area to complete the normal departure process; the microseismic monitoring sensor monitors the microseismic conditions during the mining process of the working face in real time. If the control center analyzes the impact ground pressure risk exceeding the set value based on the microseismic monitoring data, the control center will communicate wirelessly with the working cabin and the mining workers in the operating cabin to send an early warning signal, so that the mining workers can return to the refuge in the buffer zone in time to take shelter, and then enter the tunnel from the buffer zone after the external environment stabilizes, completing the emergency evacuation process; E. Continuous gas co-mining: The second group of miners repeats steps C and D to continue coal mining and extracting high-concentration gas. Subsequent groups of miners continue to repeat the same steps to achieve continuous gas co-mining. F. Temperature and pressure monitoring in the working face area: Gas extraction is carried out continuously throughout the coal mining process. Temperature sensors and pressure sensors monitor the real-time temperature and pressure of the working face area and feed them back to the control center. The control center analyzes the data and adjusts the power of the gas extraction pump station based on the real-time pressure value to keep the pressure in the working face area within the set safety threshold. At the same time, the real-time temperature value fed back is compared with the set temperature threshold. If the set temperature threshold is exceeded, it indicates that there is a gas leak in the working face area, causing coal spontaneous combustion. In this case, the mining workers in the working face area are promptly notified to evacuate. G. Recycling of the device after the mining operation is completed: When the entire coal seam is mined, check the gas concentration shown by the gas concentration sensor. If the gas concentration exceeds the set standard, continue to perform gas extraction until the extracted gas concentration is lower than the set standard. Stop gas extraction, then recycle all detachable parts, close the entire mining area, and repeat steps A to G to enter the next working face for mining.

9. The working method of the closed working face gas control system in a high-gas coal seam according to claim 8 is characterized in that: Before the working face is mined, pressure relief holes are drilled in advance of the working face to reduce the risk of rock burst during subsequent mining.

Images