In-situ testing system and method for deep mining coal oxidation spontaneous combustion

Abstract

The present application relates to a kind of deep mining coal oxidation spontaneous combustion in-situ test system, including loading mechanism, coal sample clamping mechanism, coal oxidation gas index analyzer and drive circuit, coal sample clamping mechanism is respectively with loading mechanism and coal oxidation gas index analyzer through pipeline communication, and control valve is equipped at the connection position, drive circuit is respectively with loading mechanism, coal sample clamping mechanism, coal oxidation gas index analyzer electrical connection.Its use method includes equipment prefabrication, coal sample debugging, test operation, detection reset and four steps.The present application can effectively meet the need of different structure type coal sample detection and different environment detection operation, and can effectively improve the test efficiency and detection accuracy;On the other hand, it greatly simplifies the structure of detection equipment, improves the convenience and flexibility of detection equipment operation adjustment operation, thereby effectively reducing the labor intensity and difficulty of coal sample detection operation.

Description

Technical Field

[0001] This invention relates to a device for testing the spontaneous combustion characteristics of coal samples, and more particularly to an in-situ testing system and method for spontaneous combustion of coal in deep mining. Background Technology

[0002] The determination of coal oxidation characteristics is a crucial factor in ensuring coal mine production safety and controlling mine capacity and the smooth operation of working faces. To address this issue, various structural types of coal sample spontaneous combustion characteristic detection devices and corresponding detection methods have been developed, such as the patented technologies "A Test Device for Coal Spontaneous Combustion Behavior Law under Stress-Temperature Coupling" (patent application number "202210843835.8") and "A Coal Mine Safety Monitoring Coal Spontaneous Combustion Prediction and Forecasting Equipment" (patent application number "202221702954.3"). While these technologies do not fully address the issue... While meeting the needs for coal sample characteristic testing, these systems all suffer from varying degrees of problems during use, including complex system structures, cumbersome and difficult operation, poor adaptability to coal samples, and the inability to meet the needs of specific coal sample installation experiments. Furthermore, the installation and disassembly of coal samples are quite difficult. At the same time, the efficiency of coal sample temperature control during testing is low, and energy consumption is high. Additionally, the high-temperature equipment used in coal sample testing is prone to external equipment failure due to heat transfer between equipment and between exhaust airflows, thus affecting the stability of equipment operation and the efficiency of experimental operations.

[0003] Therefore, in view of this situation, there is an urgent need to develop an in-situ testing system and method for spontaneous combustion of coal in deep mining to meet the needs of practical use. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an in-situ testing system and method for spontaneous combustion of coal in deep mining, thereby overcoming the above deficiencies and meeting the needs of actual testing operations.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A deep-mining coal oxidation spontaneous combustion in-situ testing system includes a loading mechanism, a coal sample clamping mechanism, a coal oxidation gas index analyzer, and a drive circuit. The coal sample clamping mechanism is connected to the loading mechanism and the coal oxidation gas index analyzer via pipelines, and control valves are installed at each connection point. The drive circuit is electrically connected to the loading mechanism, the coal sample clamping mechanism, and the coal oxidation gas index analyzer. The coal sample clamping mechanism includes a coal sample chamber, a piston head, a sealing plug, a support frame, a tilting mechanism, a coupling, a temperature regulating jacket, a cooling jacket, a telescopic drive column, a temperature and humidity sensor, and a pressure sensor. The support frame is a columnar frame structure with a rectangular axial cross-section. The lower half of the coal sample chamber is embedded in the upper half of the support frame and is hinged to the top of the support frame via the tilting mechanism. The coal sample chamber is a columnar cavity structure with a rectangular axial cross-section. Its upper and lower ends are connected to the sealing plug to form a closed cavity structure. The sealing plug at the top of the coal sample chamber has an air inlet and is connected to the sealing plug. The system is connected to the loading mechanism via the air inlet. The sealing plug at the bottom of the coal sample chamber has a guide hole coaxially distributed with it. The upper half of the piston head is inside the coal sample chamber, and the lower end face is outside the coal sample chamber through the guide hole. The piston head is abutted against and slidably connected to the side wall of the coal sample chamber and the wall of the guide hole, respectively. The lower end face of the piston head is connected to the telescopic drive column through a coupling. The piston head has a gas guide chamber coaxially distributed with it. The upper end face of the gas guide chamber is connected to the coal sample chamber, and the lower end face is outside the coal sample chamber and connected to the coal oxidation gas index analyzer. The telescopic drive column is embedded in the bearing frame and coaxially distributed with the bearing frame. The telescopic drive column is also connected to the loading mechanism. There is at least one temperature regulating jacket and one cooling jacket. The temperature regulating jacket covers the outside of the coal sample chamber and is coaxially distributed with it. The cooling jacket covers the outside of the telescopic drive column and is coaxially distributed with it. Both the temperature regulating jacket and the cooling jacket are connected to the loading mechanism. There is at least one temperature and humidity sensor and one pressure sensor, both located inside the coal sample chamber.

[0007] Furthermore, the loading mechanism includes a base, a hydraulic station, an air compressor, a heating liquid tank, a cooling liquid tank, a circulating pump, and a pressure sensor. The base is a frame structure with a horizontally rectangular cross-section. The hydraulic station, air compressor, heating liquid tank, and cooling liquid tank are all embedded in the base. The hydraulic station is connected to the telescopic drive column through a guide pipe. There is at least one heating liquid tank and one cooling liquid tank. The heating liquid tank is connected to the temperature regulating jacket through the circulating pump, and the cooling liquid tank is connected to the cooling jacket through the circulating pump. At the same time, the air compressor is connected to the air inlet through an air guide pipe. The two ends of the air guide pipe are connected to the air compressor and the air inlet through control valves, and a pressure sensor is installed on the air guide pipe. The hydraulic station, air compressor, heating liquid tank, cooling liquid tank, circulating pump, and pressure sensor are all electrically connected to the drive circuit.

[0008] Furthermore, the coal sample clamping mechanism is equipped with a gas filtration mechanism, which is connected to the outer side of the support frame. One end of the gas filtration mechanism is connected to the gas guiding chamber through a gas guide pipe, and the other end is connected to the coal oxidation gas index analyzer through a gas guide pipe. The gas guide pipe includes a metal tube body, heat dissipation fins, quick connectors, and control valves. The metal tube body is a hollow tubular structure with a circular cross-section. Both ends of the metal tube body are equipped with quick connectors, which are connected to the gas guiding chamber and the gas filtration mechanism respectively. Control valves are also provided at both ends of the metal tube body. In addition, at least two sedimentation grooves are provided on the inner side of the metal tube body, which are evenly distributed around its axis. The length of the sedimentation grooves is not greater than 80% of the length of the metal tube body, and their cross-section is a "U"-shaped groove structure. At the same time, several heat dissipation fins are provided on the outer surface of the metal tube body, which are evenly distributed along its axis. The heat dissipation fins are perpendicular to the axis of the metal tube body, and each heat dissipation fin is distributed around the axis of the metal tube body. The gas filtration mechanism is also electrically connected to the drive circuit.

[0009] Furthermore, the coal sample chamber includes a support column, heat exchange plates, sealing rings, a rigid insulation sleeve, and guide rails. The support column is a cylindrical cavity structure with a rectangular axial cross-section. At least one sealing ring, coaxially distributed with the support column, is provided at the connection points between its upper and lower ends and the sealing plugs. A temperature-regulating cavity, coaxially distributed with the support column, is provided on the outer surface of the support column. The heat exchange plates are T-shaped plate structures, with several plates embedded within the temperature-regulating cavity and connected to the bottom of the cavity. The surface of the heat exchange plates is perpendicular to the bottom of the temperature-regulating cavity. The heat exchangers are arranged parallel to the axis of the supporting column. The temperature regulating jacket is embedded in the temperature regulating cavity and covers the outside of the supporting column through the temperature regulating cavity. The inner side of the temperature regulating jacket abuts against the upper surface of each heat exchange plate, while the outer side of the temperature regulating jacket is 0-10 mm higher than the upper surface of the temperature regulating cavity. The rigid heat insulation sleeve covers the supporting column and the temperature regulating jacket. There are two guide rails, symmetrically distributed on both sides of the axis of the supporting column. The rotation axis of the guide rail is perpendicular to and intersects the axis of the supporting column. The guide rail covers the supporting column and the temperature regulating jacket and is connected to the flipping mechanism.

[0010] Furthermore, both the temperature regulating jacket and the cooling jacket include a heat insulation substrate, heat exchange tubes, a temperature sensor, an elastic sealing liner, connecting hinges, and connecting buckles. There are two heat insulation substrates, both being plate-like structures with an arc-shaped cross-section. One side surface of the two heat insulation substrates is hinged together by several connecting hinges, and the other side surface is connected by several connecting buckles. The two heat insulation substrates form a hollow columnar structure with a circular cross-section. Each heat insulation substrate has at least one heat exchange tube on its inner surface, and the heat exchange tubes are distributed in a spiral structure around the center point of the heat insulation substrate. Furthermore, the elastic sealing liner covers the outer surface of the heat exchange tube, and the front end face of the heat exchange tube is flush with the front end face of the elastic sealing liner. A temperature sensor is provided on the inner side of the heat insulation substrate, and the temperature sensor is electrically connected to the drive circuit. At least one electric heating wire is provided on the inner side of the temperature regulating jacket. The electric heating wire is connected to the outer side of the heat exchange tube and is distributed parallel to the axis of the heat exchange tube. The electric heating wire is provided with a terminal, and the terminal is embedded in the outer surface of the heat insulation substrate of the temperature regulating jacket. The electric heating wire is electrically connected to the drive circuit through the terminal.

[0011] Furthermore, the piston head includes a pressure-bearing column, a transmission column, a pressure-bearing spring, a tray, and sealing rings. The pressure-bearing column and transmission column are both cylindrical structures, with the lower end face of the pressure-bearing column connected to and coaxially distributed with the upper end face of the transmission column. The air guide cavity is embedded within the pressure-bearing column and transmission column, and coaxially distributed. The pressure-bearing column is located inside the coal sample chamber, and the transmission column is located outside the coal sample chamber. At least two sealing rings are provided on the outer side of both the pressure-bearing column and the tray, distributed downwards along their axes, and slidably connected to the inner side of the coal sample chamber via the sealing rings. The tray is connected to the upper end face of the pressure-bearing column via the pressure-bearing spring, and coaxially distributed. The distance between the pressure-bearing column and the tray is 0-20 mm. The tray has several through holes with a diameter not exceeding 1 mm, and the distance between two adjacent through holes is 1-5 mm. The lower end face of the pressure-bearing spring is connected to the pressure-bearing column via at least three pressure sensors evenly distributed around the axis of the pressure-bearing column. The temperature and humidity sensor is embedded within the upper end face of the pressure-bearing column and located below the tray.

[0012] Furthermore, the lower end face of the tray is connected to the upper end face of the pressure-bearing column by a flexible sleeve, which is a cylindrical hollow tubular structure and covers the pressure spring and each pressure sensor.

[0013] Furthermore, the drive circuit is a circuit system based on an industrial computer, and the drive circuit is equipped with a control box and a control interface. The drive circuit is embedded in the control box and electrically connected to the control interface, while the control interface is embedded outside the control box.

[0014] Furthermore, the supporting frame includes a base frame, a top frame, a lifting drive mechanism, and an arc-shaped guide rail. The base frame is a columnar frame structure with a rectangular axial cross-section. The telescopic drive column is embedded in the base frame and coaxially distributed with the base frame. There are two top frames, both with a rectangular cross-section. The two top frames are symmetrically distributed on both sides of the base frame axis and are connected to the upper end face of the base frame through at least one lifting drive mechanism. The coal sample chamber is located between the two top frames and coaxially distributed with the base frame. The coal sample chamber is hinged to the top frame through a flipping mechanism and slidably connected to the inner side of the top frame through an arc-shaped guide rail. The arc-shaped guide rail is connected to the inner side of the top frame, covers the flipping mechanism, and is coaxially distributed with the flipping mechanism. The coal sample chamber can rotate within the range of 0° to 120° through the flipping mechanism and the arc-shaped guide rail. The lifting drive mechanism is electrically connected to the drive circuit.

[0015] A method for using an in-situ testing system for spontaneous combustion of coal in deep mining includes the following steps:

[0016] S1, Equipment prefabrication: First, the loading mechanism, coal sample clamping mechanism, coal oxidation gas index analyzer and drive circuit are assembled. After the equipment assembly is completed, the finished product testing device is obtained. Then, the finished product testing device is driven to run and heat preservation and pressure preservation tests are carried out on the finished product testing device. After the heat preservation and pressure preservation tests are completed and passed, subsequent testing operations can be carried out.

[0017] S2, Coal Sample Adjustment: After completing step S2, the loading mechanism and coal sample clamping mechanism are operated to increase the temperature of the coal sample chamber and the coal sample inside to meet experimental requirements, while simultaneously cooling the telescopic drive column. On the other hand, the piston head of the coal sample clamping mechanism is driven to apply pressure to the coal sample. Once the coal sample pressure reaches the experimental value, high-pressure air is introduced into the coal sample chamber and the chamber is kept warm and pressurized for the test. Simultaneously, the gas in the coal sample chamber is discharged through the gas guide chamber and transported to the coal oxidation gas index analyzer for analysis and detection. Finally, the test results are output and statistically analyzed, and the statistical results are entered into the experimental data acquisition table of step S2. The axial loading pressure accuracy of the coal sample chamber is ±0.1 MPa, and the constant pressure time is not less than 10 hours; the temperature accuracy during heating and constant temperature operation of the coal sample chamber is ±0.1℃; and the high-pressure gas flow meter accuracy is ±1 ml.

[0018] S3, Test Operation: After completing step S2, the loading mechanism and coal sample clamping mechanism are operated first. On the one hand, the temperature of the coal sample chamber and the coal sample inside the coal sample clamping mechanism is increased to meet the test requirements; at the same time, the telescopic drive column is cooled. On the other hand, the piston head of the coal sample clamping mechanism is driven to apply pressure to the coal sample. After the coal sample pressure reaches the experimental value, high-pressure air is introduced into the coal sample chamber and the temperature and pressure are maintained for the test. At the same time, the gas in the coal sample chamber is discharged through the gas guide chamber and sent to the coal oxidation gas index analyzer. The coal oxidation gas index analyzer analyzes and detects the gas. Finally, the detection results are output and statistically analyzed. The statistical results are also recorded in the experimental data acquisition table of step S2.

[0019] S4, Detection Reset: After completing the detection operation in step S3, first cool and depressurize each test tank to restore the detection chamber to normal temperature and pressure. Then open each test tank and take out the tested coal sample. Clean the inside of the test tank. After completing the cleaning operation, return to step S2 to carry out subsequent operations until all coal sample detection operations are completed.

[0020] This invention features a high degree of integration and automation, and is simple and flexible to operate. It can effectively improve the efficiency and accuracy of coal sample testing. On the one hand, it can effectively meet the needs of coal sample testing with different structural types and testing operations in different environments, and effectively improve the efficiency and accuracy of testing operations. On the other hand, it greatly simplifies the structure of the testing equipment, improves the convenience and flexibility of the operation and adjustment of the testing equipment, and thus effectively reduces the labor intensity and difficulty of coal sample testing operations. Attached Figure Description

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 This is a schematic diagram of the system structure of the present invention;

[0023] Figure 2 This is a partial structural diagram of the coal sample clamping mechanism;

[0024] Figure 3 This is a schematic diagram of the coal sample chamber structure;

[0025] Figure 4 This is a schematic diagram of the piston head structure;

[0026] Figure 5 This is a schematic diagram of the loading mechanism structure;

[0027] Figure 6 This is a schematic diagram of the tracheal drainage system.

[0028] Figure 7 This is a flowchart of the method of the present invention. Detailed Implementation

[0029] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0030] like Figure 1-6 As shown, a deep-mining coal oxidation spontaneous combustion in-situ testing system includes a loading mechanism 1, a coal sample clamping mechanism 2, a coal oxidation gas index analyzer 3, and a drive circuit 4. The coal sample clamping mechanism 2 is connected to the loading mechanism 1 and the coal oxidation gas index analyzer 3 through pipelines, and control valves 5 are provided at the connection points. The drive circuit 4 is electrically connected to the loading mechanism 1, the coal sample clamping mechanism 2, and the coal oxidation gas index analyzer 3.

[0031] In this embodiment, the coal sample clamping mechanism 2 includes a coal sample chamber 21, a piston head 22, a sealing plug 23, a support frame 24, a flipping mechanism 25, a coupling 26, a temperature regulating jacket 27, a cooling jacket 28, a telescopic drive column 29, a temperature and humidity sensor 20, and a pressure sensor 201. The support frame 24 is a columnar frame structure with a rectangular axial cross-section. The lower half of the coal sample chamber 21 is embedded in the upper half of the support frame 24 and is connected to the support frame 24 via the flipping mechanism 25. The top is hinged, and the coal sample chamber 21 is a cylindrical cavity structure with a rectangular axial cross-section. Both its upper and lower ends are connected to the sealing plug 22 to form a closed cavity structure. The sealing plug 23 at the top of the coal sample chamber 21 has an air inlet 202, which communicates with the loading mechanism 1. The sealing plug 22 at the bottom of the coal sample chamber 21 has guide holes 203 coaxially distributed with it. The upper half of the piston head 22 is located inside the coal sample chamber 21, and its lower end face is positioned at the coal sample through the guide hole 203. Outside chamber 21, piston head 22 abuts against and slides against the side wall of coal sample chamber 21 and the wall of guide hole 203, and the lower end face of piston head is connected to telescopic drive column 29 through coupling 26. Piston head 22 has a coaxially distributed gas guide chamber 204. The upper end face of gas guide chamber 204 communicates with coal sample chamber 21, and the lower end face is located outside coal sample chamber 21 and communicates with coal oxidation gas index analyzer 3. Telescopic drive column 29 is embedded in the support frame 24 and is connected to the support frame 24. The components are coaxially distributed, and the telescopic drive column 29 is also connected to the loading mechanism 1. There is at least one temperature regulating jacket 27 and a cooling jacket 28. The temperature regulating jacket 27 covers the outside of the coal sample chamber 21 and is coaxially distributed with the coal sample chamber 21. The cooling jacket 28 covers the outside of the telescopic drive column 29 and is coaxially distributed with the telescopic drive column 29. Both the temperature regulating jacket 27 and the cooling jacket 28 are connected to the loading mechanism 1. There is at least one temperature and humidity sensor 20 and a pressure sensor 201, and both are located inside the coal sample chamber 21.

[0032] It should be noted that the loading mechanism 1 includes a base 11, a hydraulic station 12, an air compressor 13, a heating fluid tank 14, a coolant tank 15, a circulating pump 16, and a pressure sensor 17. The base 11 is a frame structure with a horizontally rectangular cross-section. The hydraulic station 12, air compressor 13, heating fluid tank 14, and coolant tank 15 are all embedded in the base 11. The hydraulic station 12 is connected to the telescopic drive column 29 through a guide pipe. There is at least one heating fluid tank 14 and one coolant tank 15. The tank 14 is connected to the temperature regulating jacket 27 via the circulating pump 16, and the coolant tank 15 is connected to the cooling jacket 28 via the circulating pump 16. Meanwhile, the air compressor 13 is connected to the air inlet 202 via the air guide pipe. The two ends of the air guide pipe are connected to the air compressor 13 and the air inlet 202 via the control valve 5, and a pressure sensor 17 is installed on the air guide pipe. The hydraulic station 12, air compressor 13, heating tank 14, coolant tank 15, circulating pump 16, and pressure sensor 17 are all electrically connected to the drive circuit 4.

[0033] In this embodiment, the coal sample clamping mechanism 2 is further provided with a gas filtration mechanism 6. The gas filtration mechanism 6 is connected to the outer side of the support frame 24. One end of the gas filtration mechanism 6 is connected to the gas guide chamber 204 through a gas guide pipe 7, and the other end is connected to the coal oxidation gas index analyzer 3 through a gas guide pipe 7. The gas guide pipe 7 includes a metal tube body 71, a heat dissipation fin plate 72, a quick connector 73, and a control valve 5. The metal tube body 71 is a hollow tubular structure with a circular cross-section. Both ends of the tube are provided with quick connectors 73, which are connected to the gas guide chamber 204 and the gas filtration chamber 204 through the quick connectors 73, respectively. The filter mechanism 6 is connected, and control valves 5 are provided at both ends of the metal tube 71. In addition, at least two deposition grooves 74 are provided on the inner side of the metal tube 71, which are evenly distributed around its axis. The length of the deposition grooves 74 is not greater than 80% of the length of the metal tube 71, and its cross-section is a "U"-shaped groove structure. At the same time, several heat dissipation fins 72 are provided on the outer surface of the metal tube 71, which are evenly distributed along its axis. The surface of the heat dissipation fins 72 is perpendicular to the axis of the metal tube 71, and each heat dissipation fin 72 is distributed around the axis of the metal tube. The gas filter mechanism 6 is also electrically connected to the drive circuit 4.

[0034] The airflow passing through the metal tube and heat dissipation fins is cooled to prevent damage to the coal oxidation gas index analyzer caused by the high-temperature airflow. At the same time, the dust in the airflow is settled through the sedimentation tank to reduce the damage caused by dust to the coal oxidation gas index analyzer and its impact on the test results.

[0035] Meanwhile, the coal sample chamber 21 includes a support column 211, a heat exchange plate 212, a sealing ring 213, a rigid insulation sleeve 214, and a guide rail 215. The support column 211 is a cylindrical cavity structure with a rectangular axial cross-section. At least one sealing ring 213 is provided at the connection point between its upper and lower ends and the sealing plug 23, coaxially distributed with the support column 211. A temperature regulating cavity 216 is provided on the outer side of the support column 211, coaxially distributed with it. The heat exchange plate 212 has a "T"-shaped cross-section. Several heat exchange plates 212 are embedded in the temperature regulating cavity 216 and connected to the bottom of the temperature regulating cavity 216. The surface of the heat exchange plate 212 is perpendicular to the bottom of the temperature regulating cavity 216. The temperature regulating jacket 27 is embedded in the temperature regulating cavity 216 and covers the outside of the support column 211 through the temperature regulating cavity 216. The inner side of the temperature regulating jacket 27 abuts against the upper end face of each heat exchange plate 212, while the outer side of the temperature regulating jacket 27 is 0-10 mm larger than the upper end face of the temperature regulating cavity 216. The rigid heat insulation sleeve 214 covers the support column 211 and the temperature regulating jacket 27. There are two guide slides 215, which are symmetrically distributed on both sides of the axis of the support column 211. The rotation axis of the guide slides 215 is perpendicular to and intersects the axis of the support column 211. The guide slides 215 cover the support column 211 and the temperature regulating jacket 27 and are connected to the flipping mechanism 25.

[0036] It is worth noting that both the temperature regulating jacket 27 and the cooling jacket 28 include a heat insulation substrate 271, a heat exchange tube 272, a temperature sensor 273, an elastic sealing liner 274, a connecting hinge 275, and a connecting buckle 276. There are two heat insulation substrates 271, both of which are plate-shaped structures with an arc-shaped cross-section. One side surface of the two heat insulation substrates 271 is hinged by several connecting hinges 275, and the other side surface is connected by several connecting buckles 276. The two heat insulation substrates 271 form a hollow columnar structure with a circular cross-section. Each heat insulation substrate 271 has at least one heat exchange tube 272 on its inner surface. The heat exchange tubes 272 are distributed in a spiral structure around the center point of the heat insulation substrate 271. An elastic sealing liner 274 covers the outer surface of the heat exchange tube 272, and the front end face of the heat exchange tube 272 is flush with the front end face of the elastic sealing liner 274. A temperature sensor 273 is provided on the inner side of the heat insulation substrate 271, and the temperature sensor 273 is electrically connected to the drive circuit 4. At least one electric heating wire 277 is provided on the inner side of the temperature regulating jacket 27. The electric heating wire 277 is connected to the outer side of the heat exchange tube 272 and is distributed parallel to the axis of the heat exchange tube 272. The electric heating wire 277 is provided with a terminal 278, and the terminal 278 is embedded in the outer surface of the heat insulation substrate 271 of the temperature regulating jacket 27. The electric heating wire 277 is electrically connected to the drive circuit 4 through the terminal 278.

[0037] Furthermore, the piston head 22 includes a pressure-bearing column head 221, a transmission column 222, a pressure-bearing spring 223, a tray 224, and sealing rings 213. The pressure-bearing column head 221 and the transmission column 222 are both cylindrical structures, with the lower end face of the pressure-bearing column head 221 connected to and coaxially distributed with the upper end face of the transmission column 222. The air guide cavity 204 is embedded within the pressure-bearing column head 221 and the transmission column 222, and is coaxially distributed. The pressure-bearing column head 221 is located inside the coal sample chamber 21, and the transmission column 222 is located outside the coal sample chamber 21. At least two sealing rings 213 are provided on the outer surfaces of both the pressure-bearing column head 221 and the tray 224, distributed from top to bottom along their axes. The tray 224 is slidably connected to the inner side of the coal sample chamber 21 via a sealing ring 213. The tray 224 is connected to the upper end face of the pressure column 221 via a pressure spring 223 and is coaxially distributed. The distance between the pressure column 221 and the tray 224 is 0-20 mm. The tray 224 is evenly distributed with several through holes 225 with a diameter not greater than 1 mm. The distance between two adjacent through holes 225 is 1-5 mm. The lower end face of the pressure spring 223 is connected to the pressure column 221 via at least three pressure sensors 201 evenly distributed around the axis of the pressure column 221. The temperature and humidity sensor is embedded in the upper end face of the pressure column and is located below the tray.

[0038] In a further optimized configuration, the lower end face of the tray 224 is connected to the upper end face of the pressure-bearing column head 221 by a flexible sheath 226. The flexible sheath 226 is a cylindrical hollow tubular structure and covers the pressure-bearing spring 223 and each pressure sensor 201.

[0039] In this embodiment, the drive circuit 4 is a circuit system based on an industrial computer, and the drive circuit is further provided with a control box 41 and a control interface 42. The drive circuit 4 is embedded in the control box 41 and electrically connected to the control interface 42, while the control interface 42 is embedded outside the control box 41.

[0040] Specifically, the supporting frame 24 includes a base frame 241, a top frame 242, a lifting drive mechanism 243, and an arc-shaped guide rail 244. The base frame 241 is a columnar frame structure with a rectangular axial cross-section. The telescopic drive column 29 is embedded within the base frame 241 and coaxially distributed with it. There are two top frames 242, both with rectangular cross-sections. The two top frames 242 are symmetrically distributed on both sides of the axis of the base frame 241 and are connected to the upper surface of the base frame 241 via at least one lifting drive mechanism 243. The coal... The sample chamber 21 is located between the two top frames 242 and is coaxially distributed with the bottom frame 241. The coal sample chamber 21 is hinged to the top frame 242 through a flipping mechanism 25, and is also slidably connected to the inner side of the top frame 242 through an arc guide rail 244. The arc guide rail 244 is connected to the inner side of the top frame 242, covers the flipping mechanism 25, and is coaxially distributed with the flipping mechanism 25. The coal sample chamber 21 can rotate within the range of 0° to 120° through the flipping mechanism 25 and the arc guide rail 244. The lifting drive mechanism 243 is electrically connected to the drive circuit 4.

[0041] In this embodiment, the power source of the tilting mechanism is any one of a hydraulic motor, an electric motor, and a pneumatic motor; the lifting drive mechanism 243 is any one of a hydraulic column, a pneumatic column, and a gear and rack mechanism.

[0042] A method for using an in-situ testing system for spontaneous combustion of coal in deep mining includes the following steps:

[0043] S1, Equipment prefabrication: First, the loading mechanism, coal sample clamping mechanism, coal oxidation gas index analyzer and drive circuit are assembled. After the equipment assembly is completed, the finished product testing device is obtained. Then, the finished product testing device is driven to run and heat preservation and pressure preservation tests are carried out on the finished product testing device. After the heat preservation and pressure preservation tests are completed and passed, subsequent testing operations can be carried out.

[0044] S2, Coal Sample Adjustment: After completing step S2, the loading mechanism and coal sample clamping mechanism are operated to increase the temperature of the coal sample chamber and the coal sample inside to meet experimental requirements, while simultaneously cooling the telescopic drive column. On the other hand, the piston head of the coal sample clamping mechanism is driven to apply pressure to the coal sample. Once the coal sample pressure reaches the experimental value, high-pressure air is introduced into the coal sample chamber and the chamber is kept warm and pressurized for the test. Simultaneously, the gas in the coal sample chamber is discharged through the gas guide chamber and transported to the coal oxidation gas index analyzer for analysis and detection. Finally, the test results are output and statistically analyzed, and the statistical results are entered into the experimental data acquisition table of step S2. The axial loading pressure accuracy of the coal sample chamber is ±0.1 MPa, and the constant pressure time is not less than 10 hours; the temperature accuracy during heating and constant temperature operation of the coal sample chamber is ±0.1℃; and the high-pressure gas flow meter accuracy is ±1 ml.

[0045] S3, Test Operation: After completing step S2, the loading mechanism and coal sample clamping mechanism are operated first. On the one hand, the temperature of the coal sample chamber and the coal sample inside the coal sample clamping mechanism is increased to meet the test requirements; at the same time, the telescopic drive column is cooled. On the other hand, the piston head of the coal sample clamping mechanism is driven to apply pressure to the coal sample. After the coal sample pressure reaches the experimental value, high-pressure air is introduced into the coal sample chamber and the temperature and pressure are maintained for the test. At the same time, the gas in the coal sample chamber is discharged through the gas guide chamber and sent to the coal oxidation gas index analyzer. The coal oxidation gas index analyzer analyzes and detects the gas. Finally, the detection results are output and statistically analyzed. The statistical results are also recorded in the experimental data acquisition table of step S2.

[0046] S4, Detection Reset: After completing the detection operation in step S3, first cool and depressurize each test tank to restore the detection chamber to normal temperature and pressure. Then open each test tank and take out the tested coal sample. Clean the inside of the test tank. After completing the cleaning operation, return to step S2 to carry out subsequent operations until all coal sample detection operations are completed.

[0047] This invention features a high degree of integration and automation, and is simple and flexible to operate. It can effectively improve the efficiency and accuracy of coal sample testing. On the one hand, it can effectively meet the needs of coal sample testing with different structural types and testing operations in different environments, and effectively improve the efficiency and accuracy of testing operations. On the other hand, it greatly simplifies the structure of the testing equipment, improves the convenience and flexibility of the operation and adjustment of the testing equipment, and thus effectively reduces the labor intensity and difficulty of coal sample testing operations.

[0048] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope. All such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An in-situ testing system for spontaneous combustion of coal in deep mining, characterized in that: The deep-mining coal oxidation spontaneous combustion in-situ testing system includes a loading mechanism, a coal sample clamping mechanism, a coal oxidation gas index analyzer, and a drive circuit. The coal sample clamping mechanism is connected to the loading mechanism and the coal oxidation gas index analyzer via pipelines, and control valves are installed at each connection point. The drive circuit is electrically connected to the loading mechanism, the coal sample clamping mechanism, and the coal oxidation gas index analyzer. The coal sample clamping mechanism includes a coal sample chamber, a piston head, a sealing plug, a support frame, a tilting mechanism, a coupling, a temperature regulating jacket, a cooling jacket, a telescopic drive column, a temperature and humidity sensor, and a pressure sensor. The support frame is a columnar frame structure with a rectangular axial cross-section. The lower half of the coal sample chamber is embedded in the upper half of the support frame and is hinged to the top of the support frame via the tilting mechanism. The coal sample chamber is a columnar cavity structure with a rectangular axial cross-section. Its upper and lower ends are connected to the sealing plug to form a closed cavity structure. The sealing plug at the top of the coal sample chamber has an air inlet, and the air inlet... The gas inlet is connected to the loading mechanism. The sealing plug at the bottom of the coal sample chamber has a guide hole coaxially distributed with it. The upper half of the piston head is inside the coal sample chamber, and the lower end face is outside the coal sample chamber through the guide hole. The piston head is abutted and slidably connected to the side wall of the coal sample chamber and the wall of the guide hole, and the lower end face of the piston head is connected to the telescopic drive column through a coupling. The piston head has a gas guide chamber coaxially distributed with it. The upper end face of the gas guide chamber is connected to the coal sample chamber, and the lower end face is outside the coal sample chamber and connected to the coal oxidation gas index analyzer. The telescopic drive column is embedded in the bearing frame and coaxially distributed with the bearing frame. The telescopic drive column is also connected to the loading mechanism. There is at least one temperature regulating jacket and one cooling jacket. The temperature regulating jacket covers the outside of the coal sample chamber and is coaxially distributed with it. The cooling jacket covers the outside of the telescopic drive column and is coaxially distributed with it. The temperature regulating jacket and the cooling jacket are both connected to the loading mechanism. There is at least one temperature and humidity sensor and one pressure sensor, and they are all located inside the coal sample chamber.

2. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The loading mechanism includes a base, a hydraulic station, an air compressor, a heating liquid tank, a cooling liquid tank, a circulating pump, and a pressure sensor. The base is a rectangular frame structure. The hydraulic station, air compressor, heating liquid tank, and cooling liquid tank are all embedded in the base. The hydraulic station is connected to the telescopic drive column through a guide pipe. There is at least one heating liquid tank and one cooling liquid tank. The heating liquid tank is connected to the temperature regulating jacket through the circulating pump, and the cooling liquid tank is connected to the cooling jacket through the circulating pump. The air compressor is connected to the air inlet through an air guide pipe. The two ends of the air guide pipe are connected to the air compressor and the air inlet through control valves, and a pressure sensor is installed on the air guide pipe. The hydraulic station, air compressor, heating liquid tank, cooling liquid tank, circulating pump, and pressure sensor are all electrically connected to the drive circuit.

3. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The coal sample clamping mechanism is further equipped with a gas filtration mechanism, which is connected to the outer side of the support frame. One end of the gas filtration mechanism is connected to the gas guiding chamber through a gas guide pipe, and the other end is connected to the coal oxidation gas index analyzer through a gas guide pipe. The gas guide pipe includes a metal tube body, heat dissipation fins, quick connectors, and control valves. The metal tube body is a hollow tubular structure with a circular cross-section. Both ends of the metal tube body are equipped with quick connectors, which are connected to the gas guiding chamber and the gas filtration mechanism respectively. Control valves are also provided at both ends of the metal tube body. In addition, at least two sedimentation grooves are provided on the inner side of the metal tube body, which are evenly distributed around its axis. The length of the sedimentation grooves is not greater than 80% of the length of the metal tube body, and their cross-section is a "U"-shaped groove structure. At the same time, several heat dissipation fins are provided on the outer surface of the metal tube body, which are evenly distributed along its axis. The heat dissipation fins are perpendicular to the axis of the metal tube body, and each heat dissipation fin is distributed around the axis of the metal tube body. The gas filtration mechanism is also electrically connected to the drive circuit.

4. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The coal sample chamber includes a support column, heat exchange plates, sealing rings, a rigid insulation sleeve, and guide rails. The support column is a cylindrical cavity structure with a rectangular axial cross-section. At least one sealing ring, coaxially distributed with the support column, is provided at the connection points between its upper and lower ends and the sealing plugs. A temperature-regulating cavity, coaxially distributed with the support column, is provided on the outer surface of the support column. The heat exchange plates are T-shaped plates embedded within the temperature-regulating cavities and connected to the bottom of the cavities. The surfaces of the heat exchange plates are perpendicular to the bottom of the temperature-regulating cavity and are arranged in a ring. The temperature regulating jacket is embedded in the temperature regulating cavity and covers the outside of the support column, with the inner side of the temperature regulating jacket abutting the upper surface of each heat exchange plate, and the outer side of the temperature regulating jacket being 0-10 mm higher than the upper surface of the temperature regulating cavity. The rigid heat insulation sleeve covers the support column and the temperature regulating jacket. There are two guide rails, symmetrically distributed on both sides of the support column axis, with the rotation axis of the guide rails perpendicular to and intersecting the support column axis. The guide rails cover the support column and the temperature regulating jacket and are connected to the flipping mechanism.

5. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: Both the temperature regulating jacket and the cooling jacket include a heat insulation substrate, heat exchange tubes, a temperature sensor, an elastic sealing liner, connecting hinges, and connecting buckles. There are two heat insulation substrates, both being plate-like structures with an arc-shaped cross-section. One side surface of the two heat insulation substrates is hinged together by several connecting hinges, and the other side surface is connected by several connecting buckles. The two heat insulation substrates form a hollow columnar structure with a circular cross-section. Each heat insulation substrate has at least one heat exchange tube on its inner surface, and the heat exchange tubes are distributed in a spiral structure around the center point of the heat insulation substrate. The elastic sealing liner covers the outer surface of the heat exchange tube, and the front end face of the heat exchange tube is flush with the front end face of the elastic sealing liner. A temperature sensor is provided on the inner side of the heat insulation substrate, and the temperature sensor is electrically connected to the drive circuit. At least one electric heating wire is provided on the inner side of the temperature regulating jacket. The electric heating wire is connected to the outer side of the heat exchange tube and is distributed parallel to the axis of the heat exchange tube. The electric heating wire is provided with a terminal, and the terminal is embedded in the outer surface of the heat insulation substrate of the temperature regulating jacket. The electric heating wire is electrically connected to the drive circuit through the terminal.

6. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The piston head includes a pressure-bearing column, a transmission column, a pressure-bearing spring, a tray, and sealing rings. The pressure-bearing column and transmission column are both cylindrical structures, with the lower end face of the pressure-bearing column connected and coaxially distributed with the upper end face of the transmission column. The air guide cavity is embedded within the pressure-bearing column and transmission column and coaxially distributed. The pressure-bearing column is located inside the coal sample chamber, and the transmission column is located outside the coal sample chamber. At least two sealing rings are provided on the outer side of both the pressure-bearing column and the tray, distributed from top to bottom along their axes, and slidably connected to the inner side of the coal sample chamber via the sealing rings. The tray is connected to the upper end face of the pressure-bearing column via the pressure-bearing spring and coaxially distributed. The distance between the pressure-bearing column and the tray is 0-20 mm. The tray has several through holes with a diameter no greater than 1 mm, and the distance between two adjacent through holes is 1-5 mm. The lower end face of the pressure-bearing spring is connected to the pressure-bearing column via at least three pressure sensors evenly distributed around the axis of the pressure-bearing column. The temperature and humidity sensor is embedded within the upper end face of the pressure-bearing column and located below the tray.

7. The in-situ testing system for spontaneous combustion of coal in deep mining according to claim 6, characterized in that: The lower end face of the tray is connected to the upper end face of the pressure-bearing column by a flexible sleeve. The flexible sleeve is a cylindrical hollow tubular structure and covers the pressure-bearing spring and each pressure sensor.

8. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The drive circuit is a circuit system based on an industrial computer. The drive circuit is equipped with a control box and an operating interface. The drive circuit is embedded in the control box and electrically connected to the operating interface, while the operating interface is embedded outside the control box.

9. The in-situ testing system for spontaneous combustion of coal oxidation in deep mining according to claim 1, characterized in that: The supporting frame includes a base frame, a top frame, a lifting drive mechanism, and an arc-shaped guide rail. The base frame is a columnar frame structure with a rectangular axial cross-section. The telescopic drive column is embedded in the base frame and coaxially distributed with the base frame. There are two top frames, both with a rectangular cross-section. The two top frames are symmetrically distributed on both sides of the base frame axis and are connected to the upper end face of the base frame through at least one lifting drive mechanism. The coal sample chamber is located between the two top frames and coaxially distributed with the base frame. The coal sample chamber is hinged to the top frame through a flipping mechanism and slidably connected to the inner side of the top frame through an arc-shaped guide rail. The arc-shaped guide rail is connected to the inner side of the top frame, covers the flipping mechanism, and is coaxially distributed with the flipping mechanism. The coal sample chamber can rotate within the range of 0° to 120° through the flipping mechanism and the arc-shaped guide rail. The lifting drive mechanism is electrically connected to the drive circuit.

10. A method for using an in-situ testing system for spontaneous combustion of coal in deep mining, characterized in that: The method of using the deep mining coal oxidation spontaneous combustion in-situ testing system includes the following steps: S1, Equipment prefabrication: First, the loading mechanism, coal sample clamping mechanism, coal oxidation gas index analyzer and drive circuit are assembled. After the equipment assembly is completed, the finished product testing device is obtained. Then, the finished product testing device is driven to run and heat preservation and pressure preservation tests are carried out on the finished product testing device. After the heat preservation and pressure preservation tests are completed and passed, subsequent testing operations can be carried out. S2, Coal Sample Debugging: After completing step S1, firstly, according to the needs of the testing operation, prepare several coal samples with different structural volumes, and uniformly assign identification codes to the prepared coal samples. Then, according to the identification codes, prepare a coal sample preparation experimental data collection table, and formulate a testing operation process plan for each coal sample in the data collection table. Then, according to the coal sample structure type, place the coal samples into the coal sample chamber of the coal sample clamping mechanism in sequence and seal them. S3, Test Operation: After completing step S2, the loading mechanism and coal sample clamping mechanism are operated to increase the temperature of the coal sample chamber and the coal sample inside to meet the experimental requirements, while simultaneously cooling the telescopic drive column. On the other hand, the piston head of the coal sample clamping mechanism is driven to apply pressure to the coal sample. Once the coal sample pressure reaches the experimental value, high-pressure air is introduced into the coal sample chamber and the chamber is kept warm and pressurized for the test. Simultaneously, the gas in the coal sample chamber is discharged through the gas guide chamber and transported to the coal oxidation gas index analyzer for analysis and detection. Finally, the test results are output and statistically analyzed, and the statistical results are entered into the experimental data acquisition table of step S2. The axial loading pressure accuracy of the coal sample chamber is ±0.1 MPa, and the constant pressure time is not less than 10 hours; the temperature accuracy during heating and constant temperature operation of the coal sample chamber is ±0.1℃; and the high-pressure gas flow meter accuracy is ±1 ml. S4, Detection Reset: After completing the detection operation in step S3, first cool and depressurize each test tank to restore the detection chamber to normal temperature and pressure. Then open each test tank and take out the tested coal sample. Clean the inside of the test tank. After completing the cleaning operation, return to step S2 to carry out subsequent operations until all coal sample detection operations are completed.

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