Coal low-temperature oxidation simulation explosion-proof system and method under different gas concentrations

Abstract

The application discloses a coal low-temperature oxidation explosion-proof system and method under different gas concentrations, which comprises a coal adsorbed gas amount measuring device, an explosion-proof heating oxidation reaction kettle device, a gas monitoring and analyzing device and a waste gas discharging device. Coal samples are placed in coal sample tanks, and residual gas and moisture in the coal samples are pumped out by a vacuum pump. A gas mixing proportioner is used to prepare a required gas concentration, and mixed gas is sent into the explosion-proof heating oxidation reaction kettle device to conduct a low-temperature oxidation experiment. A heat dissipation device and a pressure relief device are installed in the explosion-proof heating oxidation reaction kettle device, so that gas combustion or explosion accidents in the experiment process are effectively prevented. Meanwhile, a temperature sensor and a pressure sensor can monitor and record data in real time, and a gas chromatograph is used to analyze gas products. After the experiment, waste gas is treated by a waste gas treatment device. The system and method are simple in operation, safe and reliable, and can simulate a low-temperature oxidation process of residual coal in a goaf under different gas concentrations.

Description

Technical Field

[0001] This invention relates to the field of coal mine safety production, and in particular to a low-temperature oxidation simulation explosion-proof system and method for coal at different gas concentrations, which helps to optimize gas control in goaf areas and prevent spontaneous combustion of residual coal in goaf areas. Technical Background

[0002] As coal demand gradually increases, existing shallow coal resources are facing the risk of depletion, and many coal mines have begun to shift to deeper mining. During the mining process, large amounts of goaf are formed, leaving behind residual coal and methane gas. Because oxygen exists in the goaf, the residual coal undergoes a slow oxidation reaction under natural conditions, generating heat and toxic gases. This oxidation reaction can also trigger mine fires and gas explosions, thus affecting the safe production of coal mines.

[0003] Currently, coal adsorption research mainly focuses on the determination of adsorption parameters for multiple gases. Experimental apparatuses for oxidizing coal with different methane concentrations based on single-gas adsorption are still underdeveloped. There is a lack of apparatuses that allow for oxidation and heating experiments on coal only after it has adsorbed methane gas, under varying methane concentrations. Methane is a flammable and explosive gas; experiments at concentrations between 5% and 15% can easily cause fires and explosions, posing a high risk. Therefore, to prevent such accidents, it is necessary to design an experimental apparatus that prevents explosions during the oxidation heating process, thus ensuring experimental safety. By studying the methane content adsorbed by coal and conducting oxidation reactions at different methane concentrations, this research aims to reveal the macroscopic changes in coal under actual methane-containing oxidizing atmospheres, analyze the influence of methane on coal spontaneous combustion, and contribute to optimizing methane control technology in goaf areas, while also preventing spontaneous combustion of residual coal in goaf areas. Summary of the Invention

[0004] Technical Problem: The purpose of this invention is to overcome the shortcomings of existing technologies and provide a simple, safe, efficient, and realistic low-temperature oxidation simulation explosion-proof system and method that simulates coal under different gas concentrations during the mining process.

[0005] Technical solution: The present invention provides a low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations, comprising a coal adsorption gas measurement device, an explosion-proof heating oxidation reactor, a gas monitoring and analysis device, and a waste gas emission device;

[0006] The coal adsorption gas quantity measuring device includes a gas cylinder with a pressure gauge and a dry air cylinder with a pressure gauge, which are configured to measure the gas concentration required for the experiment. The outlets of the gas cylinder with a pressure gauge and the dry air cylinder with a pressure gauge are respectively connected to the inlet of a gas mixing and proportioning device via a first valve and a second valve for adjusting the gas output. The outlet pipe of the gas mixing and proportioning device is connected to a dehydration pipe, a first stoppered measuring cylinder, a second stoppered measuring cylinder, and a first waste gas treatment device via a four-way valve. The bottom outlet of the first stoppered measuring cylinder is connected to the bottom inlet of the second stoppered measuring cylinder. The first stoppered measuring cylinder is mounted on a support platform, and the second stoppered measuring cylinder is mounted on a lifting platform. A liquid flow meter for measuring the volume of coal adsorbed gas is installed in the pipe connecting the first stoppered measuring cylinder and the second stoppered measuring cylinder.

[0007] The explosion-proof heating oxidation reactor device includes an explosion-proof heating oxidation reactor body, which is made of 304 stainless steel explosion-proof plate to block shock waves. The top cover of the explosion-proof heating oxidation reactor body is provided with a pressure relief port and a through hole. The pressure relief port is provided with a pressure relief valve. The bottom of the explosion-proof heating oxidation reactor body is provided with a heating plate and a ceramic plate. A coal sample container is provided on the heating plate. A radiator with its bottom fixed to the inside of the top cover is provided above the coal sample container. The upper part of the explosion-proof heating oxidation reactor body is provided with multiple heat dissipation ports, and the bottom is provided with a support bracket.

[0008] The gas monitoring and analysis device includes a first pressure probe, a first temperature probe, a second temperature probe, a temperature sensor, a pressure sensor, a cooling pipe, a gas flow meter, a gas chromatograph, and a computer. The first pressure probe is connected to the first air inlet on the left side of the coal sample tank to monitor the internal pressure of the coal sample tank. The second pressure probe is connected to the space inside the explosion-proof heating oxidation reactor to monitor the internal pressure of the explosion-proof heating oxidation reactor. The first temperature probe is connected to the second air outlet on the right side of the coal sample tank to monitor the internal temperature of the coal sample tank. The second temperature probe is connected to the internal space inside the explosion-proof heating oxidation reactor to monitor the internal temperature of the explosion-proof heating oxidation reactor. The temperature sensor is connected to the first and second temperature probes and records temperature data. The pressure sensor is connected to the first and second pressure probes and records pressure data. The cooling pipe is connected to the explosion-proof heating oxidation reactor through a seventh gas valve, and the generated gas enters the computer-controlled gas chromatograph for analysis via the gas flow meter.

[0009] The exhaust gas emission device includes an exhaust gas treatment box containing activated carbon. A dust filter membrane is provided on the surface of the activated carbon inside the exhaust gas treatment box. An air inlet pipe is provided on the lower part of one side of the exhaust gas treatment box to allow air to pass through the activated carbon, and an exhaust pipe is provided on the upper part of the other side.

[0010] The four-way valve includes a third gas valve that controls the gas volume of the gas mixing and proportioning device, a fourth gas valve that controls the gas volume entering the dehydration pipe, a fifth gas valve that controls the gas volume entering the first stopper measuring cylinder, and a sixth gas valve that controls the gas volume entering the first waste gas treatment device.

[0011] The coal sample container is filled with asbestos. It has two air inlets on the left side, namely the first air inlet and the second air inlet; and two air outlets on the right side, namely the first air outlet and the second air outlet. The first air outlet is connected to a vacuum pump, and the internal gas channel runs from the second air inlet to the first air outlet.

[0012] The explosion-proof heating oxidation reactor body is equipped with a reinforcing nut on its top cover, and the surface of the explosion-proof heating oxidation reactor body is covered with an antistatic film that can reduce the possibility of gas explosion.

[0013] The first and second pressure probes in the gas monitoring and analysis device have a range of 0~1 MPa, and the first and second temperature probes have a range of 0~800℃.

[0014] The explosion-proof heating oxidation reactor body has 2-4 heat dissipation vents on its upper part.

[0015] A method for using the above-mentioned low-temperature oxidation simulation explosion-proof system for coal at different gas concentrations includes the following steps:

[0016] S1: Along the gas flow direction, connect in sequence a gas cylinder with a pressure gauge, a dry air cylinder with a pressure gauge, a gas mixing and proportioning device, a support platform, a first stoppered measuring cylinder, a liquid flow meter, a second stoppered measuring cylinder, a liquid lifting platform, a first waste gas treatment device, a dehydration pipe, an explosion-proof heating oxidation reactor, a vacuum pump, a temperature sensor, a pressure sensor, a cooling pipe, a gas chromatograph, and a computer;

[0017] S2: Perform an airtightness test: Close the first, second, third, sixth, and seventh air valves, open the fourth and fifth air valves, and start the vacuum pump to evacuate the pipeline system;

[0018] S3: After the airtightness test is passed, put the required coal sample into the coal sample container, start the vacuum pump, extract the residual gas and moisture from the coal sample, and turn off the vacuum pump when the liquid level in the first stoppered measuring cylinder is stable and no longer changes.

[0019] S4: Open the gas cylinder with pressure gauge and the dry air cylinder with pressure gauge, and open the first gas valve and the second gas valve respectively to send gas into the gas mixing and proportioning device to proportion the gas concentration that the experimental coal sample needs to adsorb.

[0020] S5: Open the third gas valve and close the fourth gas valve to allow the proportioned gas to enter the first stoppered measuring cylinder and measure the gas volume; close the third gas valve and open the fourth gas valve to allow the proportioned gas to enter the dehydration tube for drying.

[0021] S6: After the gas has been dried, it is sent into the coal sample container in the explosion-proof heating oxidation reactor. After the coal sample in the coal sample container adsorbs the gas, the gas content adsorbed by the coal is measured by the liquid flow meter between the first stopper cylinder and the second stopper cylinder.

[0022] S7: When the liquid levels in the first and second stopper cylinders no longer change, the coal sample adsorption is complete. Then, open the sixth gas valve to allow excess gas to be discharged into the atmosphere through the first waste gas treatment device.

[0023] S8: Close the fifth and sixth gas valves, open the third gas valve, and use the gas mixing and proportioning device to mix different concentrations of methane gas and introduce it into the coal sample tank in the explosion-proof heating oxidation reactor.

[0024] S9: Turn on the heating plate in the explosion-proof heating oxidation reactor to raise the temperature, and at the same time monitor and record the data through temperature and pressure sensors;

[0025] S10: During the heating process, open the seventh gas valve to allow the gas generated in the coal sample container to enter the cooling pipe. Use a gas chromatograph with a computer to analyze the gas and record the corresponding data.

[0026] S11: After the gas chromatograph analyzes the experimental gas, the resulting experimental waste gas is discharged into the atmosphere through the second waste gas treatment device.

[0027] S12: After the experiment, close all gas valves, gas cylinders with pressure gauges, and dry air cylinders with pressure gauges. After the internal temperature of the explosion-proof heating oxidation reactor drops to 30°C, open the explosion-proof heating oxidation reactor to clean the experimental coal sample.

[0028] In step S4, the gas concentration range of the gas mixing and proportioning device is 0~100%.

[0029] Beneficial Effects: By employing the above technical solution, this invention can reveal the macroscopic variation law of coal under actual gas-containing oxidizing atmosphere, which helps to optimize mine gas control technology and prevent spontaneous combustion of residual coal in goaf areas during mining. It is a complete explosion-proof experimental device and method for simulating low-temperature oxidation of gas-containing coal at different gas concentrations. It is simple to operate, safe and efficient, and realistically simulates the low-temperature oxidation process of coal after adsorbing gas at different gas concentrations during mining. By using pre-prepared gas, the gas composition and concentration are precisely guaranteed, and the gas flow direction is accurately controlled using gas valves. Experiments are conducted in an explosion-proof heating oxidation reactor, which is convenient to control, ensures uniform heating, is less affected by external conditions, and prevents combustion or explosion of gas. After the experimental gas analysis is completed, the waste gas is treated using a waste gas treatment device to ensure that it does not cause environmental pollution. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations according to the present invention.

[0031] Figure 2 yes Figure 1 Schematic diagram of the explosion-proof heating oxidation reactor.

[0032] Figure 3 yes Figure 1 Schematic diagram of the exhaust gas emission device.

[0033] Figure 4 yes Figure 2 Schematic diagram of the coal sample container structure.

[0034] In the diagram: 1-1. Gas cylinder with pressure gauge; 1-2. Dry air cylinder with pressure gauge; 2-1. First gas valve; 2-2. Second gas valve; 2-3. Third gas valve; 2-4. Fourth gas valve; 2-5. Fifth gas valve; 2-6. Sixth gas valve; 2-7. Seventh gas valve; 3. Gas mixing and proportioning device; 4. Fixed bracket; 5-1. First stoppered measuring cylinder; 5-2. Second stoppered measuring cylinder; 6-1. Liquid flow meter; 6-2. Gas flow meter; 7. Liquid lifting platform; 8-1. First waste gas treatment device; 8-2. Second waste gas treatment device; 9. Dehydration pipe; 10. Explosion-proof heating oxidation reactor body; 11. Vacuum pump; 12. Temperature sensor; 13. Pressure sensor; 14. 15. Cooling pipe, 16. Gas chromatograph, 17. Computer, 18. Pressure relief port, 19. Reinforcing nut, 20. Top cover, 21. Steel plate, 21-1. First pressure probe, 21-2. Second pressure probe, 22. Heating plate, 23. Ceramic plate, 24. Pressure relief valve, 25. Through hole, 26. Surface antistatic film, 27. Heat dissipation port, 28. Radiator, 29. Coal sample container, 30-1. First temperature probe, 30-2. Second temperature probe, 31. Support, 32-1. First air inlet, 32-2. Second air inlet, 33-1. First air outlet, 33-2. Second air outlet, 34. Asbestos, 35. Air inlet pipe, 36. Exhaust gas treatment box, 37. Dust filter membrane, 38. Drain pipe. Detailed Implementation

[0035] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings:

[0036] The low-temperature oxidation simulation explosion-proof system for coal under different methane concentrations of the present invention mainly consists of a coal adsorption methane quantity measuring device, an explosion-proof heating oxidation reactor device, a gas monitoring and analysis device, and a waste gas emission device.

[0037] The coal adsorption gas quantity measuring device includes a gas cylinder 1-1 with a pressure gauge and a dry air cylinder 1-2 with a pressure gauge, which are configured to measure the required gas concentration for the experiment. The outlets of the gas cylinder 1-1 and the dry air cylinder 1-2 with pressure gauges are respectively connected to the inlet of a gas mixing and proportioning device 3 via a first valve 2-1 and a second valve 2-2 to adjust the gas output. The outlet pipe of the gas mixing and proportioning device 3 is connected to a dehydration pipe 9, a first stoppered measuring cylinder 5-1, a second stoppered measuring cylinder 5-2, and a first waste gas treatment device 8-1 via a four-way valve. The bottom outlet of the first stoppered measuring cylinder 5-1 is... The first stoppered measuring cylinder 5-1 is located on the support platform 4, and the second stoppered measuring cylinder 5-2 is located on the lifting platform 7. The pipeline connecting the first stoppered measuring cylinder 5-1 and the second stoppered measuring cylinder 5-2 is equipped with a liquid flow meter 6-1 for measuring the volume of gas adsorbed from coal. The four-way valve includes a third gas valve 2-3 for controlling the gas volume of the gas mixing and proportioning device 3, a fourth gas valve 2-4 for controlling the gas volume entering the dewatering pipe 9, a fifth gas valve 2-5 for controlling the gas volume entering the first stoppered measuring cylinder 5-1, and a sixth gas valve 2-6 for controlling the gas volume entering the first waste gas treatment device 8-1.

[0038] The explosion-proof heating oxidation reactor device includes an explosion-proof heating oxidation reactor body 10, which is made of 304 stainless steel explosion-proof plate 20 to block shock waves. The top cover 19 of the explosion-proof heating oxidation reactor body 10 is provided with a pressure relief port 17 and a through hole 25. A pressure relief valve 24 is provided on the pressure relief port 17. A heating plate 22 and a ceramic plate 23 are provided at the bottom of the explosion-proof heating oxidation reactor body 10. A coal sample container 29 is provided on the heating plate 22. A radiator 28 with its bottom fixed to the inside of the top cover is provided above the coal sample container 29. Multiple heat dissipation ports 27 are provided on the upper part of the explosion-proof heating oxidation reactor body 10, with 2-4 ports in total. A support bracket 31 is provided at the bottom of the explosion-proof heating oxidation reactor body 10. A reinforcing nut 18 is provided on the top cover 19 of the explosion-proof heating oxidation reactor body 10. The surface of the explosion-proof heating oxidation reactor body 10 is covered with an antistatic film 26 to reduce the possibility of gas explosion.

[0039] The gas monitoring and analysis device includes a first pressure probe 21-1, a first pressure probe 21-2, a first temperature probe 30-1, a second temperature probe 31-2, a temperature sensor 12, a pressure sensor 13, a cooling pipe 14, a gas flow meter 6-2, a gas chromatograph 15, and a computer 16. The first pressure probe 21-1 is connected to the first air inlet 32-1 on the left side of the coal sample container 29 to monitor the internal pressure of the coal sample container 29. The second pressure probe 21-2 is spatially connected to the explosion-proof heating oxidation reactor body 10 to monitor the internal pressure of the explosion-proof heating oxidation reactor body 10. The first temperature probe 30-1 is connected to the second air outlet on the right side of the coal sample container 29. The first temperature sensor 30-1 is connected to the first temperature sensor 30-1 and the second temperature sensor 30-2, and the second temperature sensor 30-2 is connected to the internal space of the explosion-proof heating oxidation reactor 10 to monitor the internal temperature of the explosion-proof heating oxidation reactor 10. The second temperature sensor 12 is connected to the first temperature sensor 30-1 and the second temperature sensor 30-2 and records the temperature data. The pressure sensor 13 is connected to the first pressure sensor 21-1 and the second pressure sensor 21-2 and records the pressure data. The range of the first pressure sensor 21-1 and the second pressure sensor 21-2 is 0~1 MPa, and the range of the first temperature sensor 30-1 and the second temperature sensor 30-2 is 0~800℃. Cooling pipe 14 is connected to explosion-proof heating oxidation reactor body 10 through seventh gas valve 2-7. The generated gas enters the gas chromatograph 15 controlled by computer 16 for analysis through gas flow meter 6-2. The coal sample container 29 is filled with asbestos 34. There are two air inlets on the left side, namely the first air inlet 32-1 and the second air inlet 32-2. There are two air outlets on the right side, namely the first air outlet 33-1 and the second air outlet 33-2. The first air outlet 33-1 is connected to vacuum pump 11. The internal gas channel runs from the second air inlet 32-2 to the first air outlet 33-1.

[0040] The exhaust gas emission device includes an exhaust gas treatment box 36 containing activated carbon. A dust filter membrane 37 is provided on the surface of the activated carbon inside the exhaust gas treatment box 36. An air inlet pipe 35 for supplying air to the activated carbon is provided on the lower part of one side of the exhaust gas treatment box 36, and an exhaust pipe 38 is provided on the upper part of the other side.

[0041] The method for using the above-mentioned low-temperature oxidation simulation explosion-proof system for coal at different gas concentrations includes the following steps:

[0042] S1: Along the gas flow direction, connect in sequence: gas cylinder 1-1 with pressure gauge, dry air cylinder 1-2 with pressure gauge, first gas valve 2-1, second gas valve 2-2, gas mixing and proportioning device 3, third gas valve 2-3, support platform 4, first stoppered measuring cylinder 5-1, liquid flow meter 6-1, second stoppered measuring cylinder 5-2, liquid lifting platform 7, third gas valve 2-3, fifth gas valve 2-5, first waste gas treatment device 8-1, fourth gas valve 2-4, dehydration pipe 9, explosion-proof heating oxidation reactor body 10, vacuum pump 11, temperature sensor 12, pressure sensor 13, seventh gas valve 2-7, cooling pipe 14, gas chromatograph 15, computer 16;

[0043] S2: Perform an airtightness test: Close the first air valve 2-1, the second air valve 2-2, the third air valve 2-3, the sixth air valve 2-6, and the seventh air valve 2-7; open the fourth air valve 2-4 and the fifth air valve 2-5; and start the vacuum pump 11 to evacuate the pipeline system.

[0044] S3: After the airtightness test is passed, put the required coal sample into the coal sample container 29, start the vacuum pump 11 to extract the residual gas and moisture in the coal sample, and turn off the vacuum pump 11 when the liquid level in the first stoppered measuring cylinder 5-1 is stable and no longer changes.

[0045] S4: Open the gas cylinder 1-1 with a pressure gauge and the dry air cylinder 1-2 with a pressure gauge, and open the first gas valve 2-1 and the second gas valve 2-2 respectively to send gas into the gas mixing and proportioning device 3, and proportion the required gas concentration to be adsorbed by the experimental coal sample; the gas concentration range of the gas mixing and proportioning device 3 is 0~100%;

[0046] S5: Open the third gas valve 2-3 and close the fourth gas valve 2-4 to allow the proportioned gas to enter the first stoppered measuring cylinder 5-1 and measure the gas volume; close the third gas valve 2-3 and open the fourth gas valve 2-4 to allow the proportioned gas to enter the dehydration tube 9 for drying.

[0047] S6: After the gas has been dried, it is sent into the coal sample container 29 in the explosion-proof heating oxidation reactor 10. After the coal sample in the coal sample container 29 adsorbs the gas, the gas content adsorbed by the coal is measured by the liquid flow meter 6-1 between the first stoppered measuring cylinder 5-1 and the second stoppered measuring cylinder 5-2.

[0048] S7: When the liquid levels in the first stopper measuring cylinder 5-1 and the second stopper measuring cylinder 5-2 no longer change, the coal sample adsorption is complete. Then, open the sixth gas valve 2-6 to allow the excess gas to be discharged into the atmosphere through the first waste gas treatment device 8-1.

[0049] S8: Close the fifth gas valve 2-5 and the sixth gas valve 2-6, open the third gas valve 2-3, and use the gas mixing and proportioning device 3 to mix different concentrations of methane gas and introduce it into the coal sample tank 29 in the explosion-proof heating oxidation reactor 10;

[0050] S9: Turn on the heating plate 22 in the explosion-proof heating oxidation reactor 10 to raise the temperature, and at the same time monitor and record the data through the temperature sensor 13 and the pressure sensor 14.

[0051] S10: During the heating process, open the seventh gas valve 2-7 to allow the gas generated in the coal sample container 29 to enter the cooling pipe 14. Use the gas chromatograph 15 with computer 16 to analyze the gas and record the corresponding data.

[0052] S11: After the gas chromatograph 15 analyzes the experimental gas, the resulting experimental waste gas is discharged into the atmosphere through the second waste gas treatment device 8-2.

[0053] S12: After the experiment, close all gas valves and gas cylinder 1-1 with pressure gauge and dry air cylinder 1-2 with pressure gauge. After the internal temperature of the explosion-proof heating oxidation reactor 10 drops to 30°C, open the explosion-proof heating oxidation reactor 10 to clean the experimental coal sample.

Claims

1. A low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations, characterized in that: It includes a coal adsorption gas quantity measuring device, an explosion-proof heating oxidation reactor, a gas monitoring and analysis device, and a waste gas emission device; The coal adsorption gas quantity measuring device includes a gas cylinder (1-1) with a pressure gauge and a dry air cylinder (1-2) with a pressure gauge to set the required gas concentration for the experiment. The outlets of the gas cylinder (1-1) and the dry air cylinder (1-2) with pressure gauges are respectively connected to the inlet of a gas mixing and proportioning device (3) via a first valve (2-1) and a second valve (2-2) for adjusting the gas output. The outlet pipe of the gas mixing and proportioning device (3) is connected to a dehydration pipe (9) via a four-way valve. The first stopper measuring cylinder (5-1), the second stopper measuring cylinder (5-2), and the first waste gas treatment device (8-1) are provided. The bottom outlet of the first stopper measuring cylinder (5-1) is connected to the bottom inlet of the second stopper measuring cylinder (5-2). The first stopper measuring cylinder (5-1) is set on the support platform (4), and the second stopper measuring cylinder (5-2) is set on the lifting platform (7). A liquid flow meter (6-1) for measuring the volume of coal adsorbed gas is provided in the pipeline connecting the first stopper measuring cylinder (5-1) and the second stopper measuring cylinder (5-2). The explosion-proof heating oxidation reactor device includes an explosion-proof heating oxidation reactor body (10), which is made of 304 stainless steel explosion-proof plate (20) to block shock waves. The top cover (19) of the explosion-proof heating oxidation reactor body (10) is provided with a pressure relief port (17) and a through hole (25). The pressure relief port (17) is provided with a pressure relief valve (24). The bottom of the explosion-proof heating oxidation reactor body (10) is provided with a heating plate (22) and a ceramic plate (23). The heating plate (22) is provided with a coal sample container (29). The coal sample container (29) is provided with a radiator (28) whose bottom is fixed to the inside of the top cover. The upper part of the explosion-proof heating oxidation reactor body (10) is provided with multiple heat dissipation ports (27), and the bottom is provided with a support bracket (31). The gas monitoring and analysis device includes a first pressure probe (21-1), a second pressure probe (21-2), a first temperature probe (30-1), a second temperature probe (30-2), a temperature sensor (12), a pressure sensor (13), a cooling pipe (14), a gas flow meter (6-2), a gas chromatograph (15), and a computer (16); the first pressure probe (21-1) is connected to the first air inlet (32-1) on the left side of the coal sample tank (29) to monitor the internal pressure of the coal sample tank (29); the second pressure probe (21-2) is spatially connected to the explosion-proof heating oxidation reactor (10) to monitor the internal pressure of the explosion-proof heating oxidation reactor (10); the first temperature probe (30-1) is connected to the second air outlet (32-1) on the right side of the coal sample tank (29) to monitor the internal pressure of the explosion-proof heating oxidation reactor (10); 33-2) Connect to monitor the internal temperature of the coal sample tank (29). The second temperature probe (30-2) is connected to the internal space of the explosion-proof heating oxidation reactor (10) to monitor the internal temperature of the explosion-proof heating oxidation reactor (10). The temperature sensor (12) is connected to the first temperature probe (30-1) and the second temperature probe (30-2) and records the temperature data. The pressure sensor (13) is connected to the first pressure probe (21-1) and the second pressure probe (21-2) and records the pressure data. The cooling pipe (14) is connected to the explosion-proof heating oxidation reactor (10) through the seventh gas valve (2-7). The generated gas enters the gas chromatograph (15) controlled by the computer (16) through the gas flow meter (6-2) for analysis. The exhaust gas emission device includes an exhaust gas treatment box (36) containing activated carbon. A dust filter membrane (37) is provided on the surface of the activated carbon in the exhaust gas treatment box (36). An air inlet pipe (35) for air to be supplied to the activated carbon is provided on the lower part of one side of the exhaust gas treatment box (36), and an exhaust pipe (38) is provided on the upper part of the other side. The coal sample container (29) is filled with asbestos (34). There are two air inlets on the left side, namely the first air inlet (32-1) and the second air inlet (32-2); there are two air outlets on the right side, namely the first air outlet (33-1) and the second air outlet (33-2). The first air outlet (33-1) is connected to the vacuum pump (11), and the internal gas channel runs from the second air inlet (32-2) to the first air outlet (33-1). After the airtightness test is passed, the required coal sample is put into the coal sample container (29), the vacuum pump (11) is started, and the residual gas and moisture in the coal sample are extracted. When the liquid level in the first stoppered measuring cylinder (5-1) is stable and no longer changes, the vacuum pump (11) is turned off. The explosion-proof heating oxidation reactor body (10) is provided with a reinforcing nut (18) on the top cover (19), and the surface of the explosion-proof heating oxidation reactor body (10) is covered with an antistatic film (26) that can reduce the possibility of gas explosion. The four-way valve includes a third gas valve (2-3) that controls the gas volume of the gas mixing and proportioning device (3), a fourth gas valve (2-4) that controls the gas volume entering the dehydration pipe (9), a fifth gas valve (2-5) that controls the gas volume entering the first stopper measuring cylinder (5-1), and a sixth gas valve (2-6) that controls the gas volume entering the first waste gas treatment device (8-1).

2. The low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations according to claim 1, characterized in that: The range of the first pressure probe (21-1) and the second pressure probe (21-2) in the gas monitoring and analysis device is 0~1 MPa, and the range of the first temperature probe (30-1) and the second temperature probe (30-2) is 0~800℃.

3. The low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations according to claim 1, characterized in that: The explosion-proof heating oxidation reactor body (10) has 2-4 heat dissipation ports (27) on its upper part.

4. A method for using the low-temperature oxidation simulation explosion-proof system for coal under different gas concentrations as described in any one of claims 1-3, characterized in that... Includes the following steps: S1: Along the gas flow direction, connect in sequence the following gas cylinders: gas cylinder with pressure gauge (1-1), dry air cylinder with pressure gauge (1-2), gas mixing and proportioning device (3), support platform (4), first stoppered measuring cylinder (5-1), liquid flow meter (6-1), second stoppered measuring cylinder (5-2), liquid lifting platform (7), first waste gas treatment device (8-1), dehydration pipe (9), explosion-proof heating oxidation reactor body (10), vacuum pump (11), temperature sensor (12), pressure sensor (13), cooling pipe (14), gas chromatograph (15), and computer (16). S2: Perform an airtightness test: Close the first air valve (2-1), the second air valve (2-2), the third air valve (2-3), the sixth air valve (2-6), and the seventh air valve (2-7), open the fourth air valve (2-4) and the fifth air valve (2-5), and start the vacuum pump (11) to evacuate the pipeline system; S3: After the air tightness test is passed, the required coal sample is put into the coal sample container (29), the vacuum pump (11) is started to extract the residual gas and moisture in the coal sample, and the vacuum pump (11) is turned off when the liquid level in the first stoppered measuring cylinder (5-1) is stable and no longer changes. S4: Open the gas cylinder (1-1) with pressure gauge and the dry air cylinder (1-2) with pressure gauge, and open the first gas valve (2-1) and the second gas valve (2-2) respectively to send gas into the gas mixing and proportioning device (3) to proportion the gas concentration required to be adsorbed by the experimental coal sample; the gas concentration range of the gas mixing and proportioning device (3) is 0~100%; S5: Open the third gas valve (2-3), close the fourth gas valve (2-4), and let the proportioned gas enter the first stoppered measuring cylinder (5-1) and measure the gas volume; close the third gas valve (2-3), open the fourth gas valve (2-4), and let the proportioned gas enter the dehydration tube (9) for drying; S6: After the gas has been dried, it is sent into the coal sample tank (29) in the explosion-proof heating oxidation reactor (10). After the coal sample in the coal sample tank (29) adsorbs the gas, the gas content adsorbed by the coal is measured by the liquid flow meter (6-1) between the first stopper measuring cylinder (5-1) and the second stopper measuring cylinder (5-2). S7: When the liquid levels in the first stopper measuring cylinder (5-1) and the second stopper measuring cylinder (5-2) no longer change, the coal sample adsorption is complete. Then, open the sixth gas valve (2-6) to allow the excess gas to be discharged into the atmosphere through the first waste gas treatment device (8-1). S8: Close the fifth gas valve (2-5) and the sixth gas valve (2-6), open the third gas valve (2-3), and use the gas mixing and proportioning device (3) to mix different concentrations of methane gas and introduce them into the coal sample tank (29) in the explosion-proof heating oxidation reactor (10); S9: Turn on the heating plate (22) in the explosion-proof heating oxidation reactor (10) to raise the temperature, and at the same time monitor and record the data through the temperature sensor (12) and pressure sensor (13); S10: During the heating process, open the seventh gas valve (2-7) to allow the gas generated in the coal sample container (29) to enter the cooling pipe (14). Use a gas chromatograph (15) with a computer (16) to analyze the gas and record the corresponding data. S11: After the gas chromatograph (15) analyzes the experimental gas, the resulting experimental waste gas is discharged into the atmosphere through the second waste gas treatment device (8-2); S12: After the experiment, close all gas valves and gas cylinders (1-1) and dry air cylinders (1-2) with pressure gauges. When the internal temperature of the explosion-proof heating oxidation reactor (10) drops to 30°C, open the explosion-proof heating oxidation reactor (10) to clean the experimental coal sample.

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