A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt

Abstract

The present invention relates to the field of coal mine safety, and particularly to a method for warning of belt fire by implanting temperature-sensitive materials in a belt. Temperature-sensitive materials with different decomposition temperatures are ground into powders with a particle size between 250 and 300 μm, and are implanted into the upper and lower cover layers of the mine transport belt by means of an isobaric impact injection pipe, and the prepared belt is used in mine transport. When the belt is abnormally rubbed and heated to the pyrolysis temperature of the temperature-sensitive material, different temperature-sensitive materials release different characteristic gases. The gas detector monitors the change in gas concentration and production rate, and transmits the signal to the data processor. The development of the belt fire is judged through the warning model, and different warning messages are issued. The present invention can effectively monitor the transport belt in the coal mine underground, timely detect the abnormality of the belt operation, and thus avoid possible fire accidents.

Description

Technical Field

[0001] The present invention relates to the field of coal mine safety, and particularly to a method for warning of belt conveyor fires by implanting temperature-sensitive materials in a belt. Background Art

[0002] In external coal mine fire accidents, most fires are caused by belt conveyor fires. According to different disaster-causing reasons, belt fires are divided into the following two types: fires caused by belt friction and fires caused by non-belt friction. The former is mainly caused by the belt being stuck, resulting in the driving roller slipping completely, and then the belt and the roller rub against each other to catch fire, as well as high-speed friction between the belt conveyor roller and idler and the belt after mechanical failures; the latter is mainly caused by the overheating of faulty electrical equipment of the belt conveyor in a short time, resulting in the belt catching fire, and the spontaneous combustion of coal on the belt igniting the belt, causing a belt conveyor fire.

[0003] At present, China mainly uses sensing technologies such as CO sensors, smoke sensors, and temperature sensors to achieve belt fire monitoring and warning. However, due to the influence of the installation position, the temperature sensor cannot achieve the purpose of early prediction of belt fires; the low-temperature oxidation of coal also produces CO, resulting in the inability of CO detection to accurately warn of belt conveyor fires; when the smoke detection issues an alarm message, the belt has already entered the initial combustion stage. Therefore, the above methods cannot accurately warn of the occurrence of belt conveyor fires. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for warning of belt conveyor fires by implanting temperature-sensitive materials in a belt. The temperature-sensitive materials are implanted into the cover layer of the belt for mine transportation by using an isobaric impact injection tube, and then a special gas detector is used to monitor and transmit signals of the gas and gas concentration generated by the temperature-sensitive materials when heated, effectively improving the safety production level in the mine roadway and ensuring the safety of the lives of workers. The technical solution adopted is as follows:

[0005] A method for warning of belt conveyor fires by implanting temperature-sensitive materials in a belt specifically includes the following steps:

[0006] (1) Grind several different types of solid temperature-sensitive materials to a powder particle size between 250 - 300 um;

[0007] (2) Load the temperature-sensitive materials into an isobaric impact injection tube, and use the isobaric impact injection tube to implant the temperature-sensitive materials into the cover layer of the belt for mine transportation. Different types of temperature-sensitive materials are evenly implanted at regular intervals in the upper and lower cover layers of the belt. When the belt temperature changes, the corresponding materials in the temperature-sensitive materials will decompose when heated to produce different gases;

[0008] (3) The belt is used for mine transportation. On the downwind side of the air intake in the mine roadway, several characteristic gas detectors are vertically hung at uniform intervals of 30 - 50 meters along the air intake direction above the conveyor head. Each characteristic gas detector is connected in parallel and each is equipped with a different code. A data receiving and processing unit, a regional alarm device, and a regional display are also installed in the mine roadway. The characteristic gas detectors are connected to the data receiving and processing unit, the data receiving and processing unit is connected to the regional alarm device and the regional display, and the regional alarm device and the regional display are connected to the mine central control system. When each of the characteristic gas detectors monitors signals of different gases and the change rules of gas concentrations, the signals are transmitted to the data receiving and processing unit. The data receiving and processing unit forms a belt fire classification early warning based on the built-in early warning model, and uses the regional alarm device and the regional display to transmit the early warning information to the mine central control room and on-site workers.

[0009] Preferably, the isobaric impact injection pipe is powered by a gas source gun with a Laval nozzle diameter of 4 mm, an operating pressure of 50 MPa, and a bursting pressure of 80 MPa.

[0010] Preferably, when the isobaric impact injection pipe implants the upper and lower cover layers of the belt, the central axis of the isobaric impact injection pipe is perpendicular to the belt surface, the nozzle is 1 cm away from the upper and lower cover layers of the belt, and it is implanted once every 20 cm horizontally and 40 cm vertically. The implantation depth is 0.1 - 0.5 mm, and the single-hole implantation amount is 0.1 - 1 g.

[0011] Preferably, the thermosensitive materials are ammonium bicarbonate powder with a decomposition temperature of 50 - 60 °C, selenium bromide powder with a decomposition temperature of 70 - 90 °C, and aluminum chloride hexahydrate powder with a decomposition temperature of 110 - 120 °C.

[0012] Preferably, the total amount of ammonium bicarbonate powder, selenium bromide powder, and aluminum chloride hexahydrate powder added is 0.1% - 1% of the mass fraction of the rubber in the belt cover layer.

[0013] Preferably, each of the characteristic gas detectors can detect the gases generated by the thermal decomposition of the thermosensitive materials and their concentration changes. They are respectively installed on the downwind side of the air intake in the mine roadway and are vertically hung at intervals along the air intake direction above the head, 0.3 meters away from the roof of the roadway and 0.2 meters away from the side wall of the roadway in a straight line.

[0014] Preferably, the early warning model is determined according to the decomposition temperature of the thermosensitive material, the types and concentration changes of different gases generated by the belt under heat, and is divided into four levels of early warning, namely: the first level, ammonia is detected, and the temperature range is 50-70°C; the second level, based on the first level, bromine, hydrogen bromide or the ratio of CO2 / CO is detected to be 3, and the temperature range is 70-110°C; the third level, based on the first and second levels, hydrogen chloride or C2H4 is detected, and the temperature range is 110-150°C; the fourth level, a rapid increase in C2H4 is detected or soot is detected, and the temperature range is above 150°C;

[0015] The data receiving and processing unit processes the data transmitted by the characteristic gas detector based on the internal early warning model, judges the level of the belt fire, and transmits the alarm information to the area alarm device and the area display.

[0016] Preferably, after receiving the transmitted alarm information, the area alarm device can display the corresponding belt temperature and gas concentration information, and transmit the early warning information to the mine central control system; the area display is connected to the area alarm device, and the detector code of the characteristic gas detected can be displayed on the area display.

[0017] Preferably, a bus isolator is provided between the power supply bus for connection and the signal bus for transmission in the method for early warning belt fire, and a fire protection module is also provided on the signal bus.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The present invention designs a method for implanting a thermosensitive material in a belt, and a method for using the belt prepared by this method to early warn of belt fire. Since the thermosensitive material for early warning is evenly fused with the belt through an isobaric impact injection tube into the upper and lower cover layers of the belt, implanted once at a horizontal interval of 20 cm and a vertical interval of 40 cm, and the implantation depth is 0.1-0.5 mm. When the belt is exposed to high temperature, the implanted thermosensitive material immediately releases gas due to the temperature effect. After the characteristic gas detector detects the characteristic gas, it immediately issues an early warning, thus enabling an earlier early warning time for belt fire and higher prediction accuracy. This method can provide an effective way to accurately judge the location of the fire source and the development of the fire situation for mine belt fires, thereby reducing the possibility of belt fire caused by abnormal belt operation and greatly improving the safety of the mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of implanting a thermosensitive material into a belt using an isobaric impact injection tube in the present invention;

[0021] Figure 2 is an enlarged schematic diagram of the belt after implanting the thermosensitive material in the present invention;

[0022] Figure 3 It is a graph showing the relationship between the concentration of gas released by the thermosensitive material of the present invention upon heating and the temperature rise;

[0023] Figure 4 It is a structural diagram of the belt prepared by the present invention applied in a mine.

[0024] In the figure, 1 is the belt; 2 is the characteristic gas detector; 3 is the data receiving and processing unit; 4 is the area alarm device; 5 is the area display; 6 is the fire protection module; 7 is the SI bus isolator; 8 is the isobaric impact injection pipe; 9 is the thermosensitive material powder; 10 is the power supply bus; 11 is the signal bus. Detailed implementation mode

[0025] The attached drawings are only for illustrative purposes; it should be understood that the cases mentioned below are only used to explain the present invention, for the convenience of describing the present invention and simplifying the description, and therefore, should not be construed as a limitation to the present invention.

[0026] The principles and features of the present invention will be described below in conjunction with embodiments. The embodiments cited are only used to explain the present invention and are not intended to limit the scope of the present invention. For those not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0027] The present invention will be further described below in conjunction with embodiments and the attached drawings.

[0028] Embodiment 1

[0029] Implementation background: A certain mine plans to install a conveyor belt with a transportation capacity requirement of 1200 t / h, using a main motor with a power of 4 * 200 kw as the driving device. The conveyor belt has a width of 1200 mm and a strength of 1000 KN / mm. It is planned to use a method of blending a thermosensitive material in the belt of the present invention to prepare the belt and apply the belt to the belt fire warning system. The specific steps are as follows:

[0030] As Figure 1 shown, the composition of the cover layer of the PVG1250S type conveyor belt used in this roadway is improved, and a thermoplastic elastomer is selected as the rubber for the cover layer.

[0031] A method for warning the fire of a conveyor belt by implanting a thermosensitive material in a belt specifically includes the following steps:

[0032] (1) Mix ammonium bicarbonate powder with a decomposition temperature of 50 - 60 °C, selenium bromide powder with a decomposition temperature of 70 - 90 °C, and aluminum chloride hexahydrate powder with a decomposition temperature of 110 - 120 °C, and grind to a powder particle size of about 250; the grinding tool can be a conventional grinding tool.

[0033] (2) Based on the actual belt injection experiment, select and adapt each component of the isobaric impact injection tube 8: The diameter of the Laval nozzle selected is 4 mm; A new type of gas source gun with an operating pressure of 50 MPa and a burst pressure of 80 MPa is selected to provide power; A gas source volume of 100 ml is selected to ensure sufficient injection power; For the selection of the firing device, a new type of double solenoid valve firing device with a firing frequency of more than ten thousand times and a diameter of 4 mm is selected;

[0034] As Figure 1 、 2 shown, load the ground temperature-sensitive material powder 9 after grinding into the isobaric impact injection tube 8, make the isobaric impact injection tube 8 perpendicular to the surface of the belt 1, and the nozzle is 1 cm away from the upper and lower cover layers of the belt 1. Implantation is successively completed at intervals of 20 cm transversely and 40 cm longitudinally on the belt, the implantation depth is 0.1 mm, and the single-hole implantation amount is 0.1 g. The total amount of ammonium bicarbonate powder, selenium bromide powder and aluminum chloride hexahydrate powder added is 0.1% of the mass fraction of the rubber in the belt cover layer. When the belt temperature changes, the corresponding materials in the temperature-sensitive material will decompose when heated to produce different gases;

[0035] As Figure 3 shown, conduct a heating experiment on the belt after implantation and use an instrument to detect the gases pyrolyzed inside the belt, and obtain an image of the relationship between gas concentration and temperature. It can be seen from the graph that when the temperature is about 55 °C, ammonia is released, when the temperature is about 80 °C, gaseous bromine is released, and when the temperature is about 110 °C, hydrogen chloride gas is released, indicating that the belt prepared by the method of implanting the temperature-sensitive material into the upper and lower cover layers of the belt using the isobaric impact injection tube meets the requirements of releasing gases at different temperatures.

[0036] (3) Use the belt prepared above in mine transportation. As Figure 4 shown, on the downwind side of the mine roadway intake air, along the intake air direction above the conveyor head, evenly space and vertically hang a characteristic gas detector 2 at intervals, and install multiple ones. Each characteristic gas detector 2 is connected in parallel, and each is equipped with a different code; A data receiving and processing device 3, a regional alarm device 4 and a regional display 5 are also installed in the mine roadway. The characteristic gas detector 2 is connected to the data receiving and processing device 3, the data receiving and processing device 3 is connected to the regional alarm device 4 and the regional display 5, and the regional alarm device 4 and the regional display 5 are connected to the mine central control system; When each of the characteristic gas detectors 2 monitors signals of different gases and gas concentration change rules, the signals are transmitted to the data receiving and processing device 3, and the data receiving and processing device 3 forms a belt fire classification early warning based on its built-in early warning model, and uses the regional alarm device 4 and the regional display 5 to transmit the early warning information to the mine central control room and on-site staff.

[0037] For Figure 4 a small part of the belt in, it can be seen that asFigure 2 The front view sectional drawing and top view of the enlarged belt. There is a circle of temperature-sensitive material on the belt with a relatively small interval distance. When the belt is heated, gas will be released, and the special gas detector 2 will detect it, meeting the early warning requirements.

[0038] As a further preference, one feature gas detector 2 is set every 30 meters and is respectively installed on the downwind side of the intake air in the mine roadway. They are vertically suspended at intervals along the intake air direction above the head of the belt conveyor, 0.3 meters away from the roof of the roadway and 0.2 meters away from the side wall of the roadway in a straight line. The signals sent by any feature gas detector 2 can be displayed and processed on the area display 5, and finally the mine central control system can also receive them.

[0039] The early warning model is determined according to the decomposition temperature of the temperature-sensitive material, the types and concentration changes of different gases generated by the heated belt, and is divided into four levels of early warning, namely: the first level, ammonia is detected, and the temperature range is 50 - 70 °C; the second level, based on the first level, bromine, hydrogen bromide or the ratio of CO2 / CO is 3, and the temperature range is 70 - 110 °C; the third level, based on the first and second levels, hydrogen chloride or C2H4 is detected, and the temperature range is 110 - 150 °C; the fourth level, a rapid increase in C2H4 is detected or soot is detected, and the temperature range is above 150 °C.

[0040] The data receiving and processing unit 3 processes the data transmitted by the feature gas detector based on the internal early warning model, judges the level of the belt fire, and transmits the alarm information to the area alarm device 4 and the area display 5.

[0041] After receiving the transmitted alarm information, the area alarm device 4 can display the corresponding temperature of the belt 1 and gas concentration information, and transmit the early warning information to the mine central control system; the area display 5 is connected to the area alarm device 4, and the code of the feature gas detector 2 that detects the feature gas can be displayed on the area display 5, so as to accurately locate the abnormal area.

[0042] For the safety in the mine, a fire protection module 6 is also provided on the signal bus 9 in the mine, which is connected to the mine central control system for input, output and feedback signals; a bus isolator 7 is provided between the power supply bus 8 and the signal bus 9 to avoid line crossing and adhesion.

[0043] The working process of the above-mentioned conveyor belt fire warning system is as follows: When the conveyor belt 1 undergoes abnormal working conditions resulting in belt temperature rise, the thermosensitive solid materials in the conveyor belt 1 are decomposed by heat respectively. At about 55°C, ammonia gas is released; at about 80°C, gaseous bromine is released; and at about 110°C, hydrogen chloride gas is released. The characteristic gas detector 2 detects the gas and the change in gas concentration, and transmits the data to the data acquisition and processing center. Then, through the built-in warning model, it judges the occurrence and development of the conveyor belt fire, and issues different alarm levels according to the actual situation, so as to ensure the safety of the mine.

[0044] Example 2

[0045] A method for warning conveyor belt fire by implanting thermosensitive materials in the conveyor belt specifically includes the following steps:

[0046] (1) Mix ammonium bicarbonate powder with a decomposition temperature of 50 - 60°C, selenium bromide powder with a decomposition temperature of 70 - 90°C, and aluminum chloride hexahydrate powder with a decomposition temperature of 110 - 120°C, and grind them until the powder particle size is about 280; the grinding tool can be a conventional grinding tool.

[0047] (2) According to the actual belt injection experiment, select and adapt each component of the isobaric impact injection pipe 8: The selected Laval nozzle has a diameter of 4 mm; a new type of gas source gun with a working pressure of 50 MPa and a bursting pressure of 80 MPa is selected to provide power; a gas source volume of 100 ml is selected to ensure sufficient injection power; for the selection of the firing device, a new type of double solenoid valve firing device with a firing frequency of more than ten thousand times and a diameter of 4 mm is selected;

[0048] As Figure 1 、 2 shown, load the ground thermosensitive material powder 9 into the isobaric impact injection pipe 8, make the isobaric impact injection pipe 8 perpendicular to the surface of the conveyor belt 1, and the nozzle is 1 cm away from the upper and lower cover layers of the conveyor belt 1. Implantation is completed in sequence at intervals of 20 cm horizontally and 40 cm vertically on the conveyor belt, the implantation depth is 0.3 mm, and the single-hole implantation amount is 0.5 g. The total amount of ammonium bicarbonate powder, selenium bromide powder, and aluminum chloride hexahydrate powder added is 0.5% of the rubber mass fraction of the conveyor belt cover layer. When the conveyor belt temperature changes, the corresponding materials in the thermosensitive material will be decomposed by heat to generate different gases;

[0049] As Figure 3As shown, a heating experiment was conducted on the belt after implantation, and the gas pyrolyzed inside the belt was detected by an instrument to obtain an image of the relationship between gas concentration and temperature. It can be seen from the figure that when the temperature is around 50°C, ammonia is released; when the temperature is around 75°C, gaseous bromine is released; and when the temperature is around 110°C, hydrogen chloride gas is released. This indicates that the belt prepared by implanting the temperature-sensitive material into the upper and lower cover layers of the belt using an isobaric impact injection tube meets the requirements for releasing gases at different temperatures.

[0050] (3) Use the belt prepared above for mine transportation. As Figure 4 shown, on the downwind side of the incoming air in the mine roadway, along the incoming air direction from above the conveyor head, a characteristic gas detector 2 is vertically suspended at uniform intervals. Multiple are installed. Each characteristic gas detector 2 is connected in parallel, and each is equipped with a different code; a data receiving and processing device 3, a regional alarm device 4, and a regional display 5 are also installed in the mine roadway. The characteristic gas detector 2 is connected to the data receiving and processing device 3, the data receiving and processing device 3 is connected to the regional alarm device 4 and the regional display 5, and the regional alarm device 4 and the regional display 5 are connected to the mine central control system; when each of the characteristic gas detectors 2 detects signals of different gases and the variation law of gas concentration, the signals are transmitted to the data receiving and processing device 3. The data receiving and processing device 3 forms a belt fire classification early warning based on its built-in early warning model, and uses the regional alarm device 4 and the regional display 5 to transmit the early warning information to the mine central control room and on-site staff.

[0051] As a further preference, a characteristic gas detector 2 is set every 40 meters, and they are respectively installed on the downwind side of the incoming air in the mine roadway. They are vertically suspended at intervals along the incoming air direction from above the head, 0.3 meters away from the roof of the roadway and 0.2 meters away from the side wall of the roadway in a straight line. Whichever characteristic gas detector 2 emits a signal can be displayed and processed on the regional display 5, and finally the mine central control system can also receive it.

[0052] Other parts not mentioned are the same as in Embodiment 1.

[0053] Embodiment 3

[0054] A method for warning of belt fire by implanting temperature-sensitive material in a belt specifically includes the following steps:

[0055] (1) Mix ammonium bicarbonate powder with a decomposition temperature of 50 - 60°C, selenium bromide powder with a decomposition temperature of 70 - 90°C, and aluminum chloride hexahydrate powder with a decomposition temperature of 110 - 120°C, and grind them until the particle size of the powder is about 300; the grinding tool can be a conventional grinding tool.

[0056] (2) Based on the actual belt injection experiment, select and adapt each component of the isobaric impact injection pipe 8: The diameter of the Laval nozzle selected is 4 mm; A new type of gas source gun with an operating pressure of 50 MPa and a burst pressure of 80 MPa is selected to provide power; A gas source volume of 100 ml is selected to ensure sufficient injection power; For the selection of the firing device, a new type of double solenoid valve firing device with a firing frequency of more than ten thousand times and a diameter of 4 mm is selected;

[0057] As Figure 1 、 2 shown, load the ground temperature-sensitive material powder 9 after grinding into the isobaric impact injection pipe 8, make the isobaric impact injection pipe 8 perpendicular to the surface of the belt 1, and the nozzle is 1 cm away from the upper and lower cover layers of the belt 1. Implantation is successively completed at intervals of 20 cm transversely and 40 cm longitudinally on the belt, the implantation depth is 0.5 mm, and the single-hole implantation amount is 1 g. The total amount of ammonium bicarbonate powder, selenium bromide powder and aluminum chloride hexahydrate powder added is 1% of the rubber mass fraction. When the belt temperature changes, the corresponding materials in the temperature-sensitive material will decompose by heat to produce different gases;

[0058] As Figure 3 shown, conduct a heating experiment on the belt after implantation and use an instrument to detect the gases pyrolyzed inside the belt, and obtain an image of the relationship between gas concentration and temperature. It can be seen from the figure that when the temperature is about 50 °C, ammonia is released, when the temperature is about 70 °C, gaseous bromine is released, and when the temperature is about 110 °C, hydrogen chloride gas is released, indicating that the belt prepared by the method of implanting the temperature-sensitive material into the upper and lower cover layers of the belt using the isobaric impact injection pipe meets the requirements of releasing gases at different temperatures.

[0059] (3) Use the belt prepared above in mine transportation. As Figure 4 shown, on the downwind side of the incoming air in the mine roadway, along the incoming air direction above the conveyor head, evenly and vertically hang a characteristic gas detector 2 at intervals, and install multiple. Each of the characteristic gas detectors 2 is connected in parallel, and each is equipped with a different code; A data receiving and processing device 3, a regional alarm device 4 and a regional display 5 are also installed in the mine roadway. The characteristic gas detector 2 is connected to the data receiving and processing device 3, the data receiving and processing device 3 is connected to the regional alarm device 4 and the regional display 5, and the regional alarm device 4 and the regional display 5 are connected to the mine central control system; When each of the characteristic gas detectors 2 monitors signals of different gases and the variation law of gas concentration, the signals are transmitted to the data receiving and processing device 3, and the data receiving and processing device 3 forms a belt fire classification early warning based on its built-in early warning model, and uses the regional alarm device 4 and the regional display 5 to transmit the early warning information to the mine central control room and on-site staff.

[0060] As a further preference, one characteristic gas detector 2 is provided at an interval of 50 meters, and they are respectively installed on the downwind side of the incoming air in the mine roadway. They are vertically suspended at intervals along the incoming air direction above the machine head, 0.3 meters away from the roof of the roadway and 0.2 meters away from the side wall of the roadway in a straight line. The signals sent by any characteristic gas detector 2 can be displayed and processed on the area display, and finally the mine central control system can also receive them.

[0061] For other parts not described, they are the same as those in Embodiment 1.

[0062] Those of ordinary skill in the art will realize that the experimental examples shown here are to help readers understand the principles of the present invention. It should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other deformations in other aspects that do not deviate from the essence of the present invention according to these technical revelations disclosed in the present invention, and these deformations are still within the protection scope of the present invention.

Claims

1. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt, characterized in that, Specifically, it includes the following steps: (1) Grind several different types of solid thermosensitive materials to a powder particle size between 250 - 300 μm; (2) Load the thermosensitive materials into an isobaric impact injection tube, and use the isobaric impact injection tube to implant the thermosensitive materials into the belt covering layer for mine transportation. Different types of thermosensitive materials are evenly spaced and implanted at a certain distance in the upper and lower covering layers of the belt. When the belt temperature changes, the corresponding materials in the thermosensitive materials will decompose when heated to produce different gases; (3) Use the belt for mine transportation. On the downwind side of the incoming air in the mine roadway, several characteristic gas detectors are vertically suspended at uniform intervals of 30 - 50 meters along the incoming air direction above the conveyor head. Each characteristic gas detector is connected in parallel and each is equipped with a different code; A data receiving and processing device, a regional alarm device, and a regional display are also installed in the mine roadway. The characteristic gas detectors are connected to the data receiving and processing device, the data receiving and processing device is connected to the regional alarm device and the regional display, and the regional alarm device and the regional display are connected to the mine central control system; When each of the characteristic gas detectors detects signals of different gases and the change rules of gas concentration, the signals are transmitted to the data receiving and processing device. The data receiving and processing device forms a belt fire classification early warning based on the built-in early warning model, and uses the regional alarm device and the regional display to transmit the early warning information to the mine central control room and on-site staff; Among them, the thermosensitive materials are ammonium bicarbonate powder with a decomposition temperature of 50 - 60 °C, selenium bromide powder with a decomposition temperature of 70 - 90 °C, and aluminum chloride hexahydrate powder with a decomposition temperature of 110 - 120 °C; The early warning model is determined according to the decomposition temperature of the thermosensitive materials, the types and concentration changes of different gases generated when the belt is heated, and is divided into four levels of early warning, namely: The first level, ammonia is detected, and the temperature range is 50 - 70 °C; The second level, based on the first level, bromine, hydrogen bromide, or the ratio of CO2 / CO is 3 is detected, and the temperature range is 70 - 110 °C; The third level, based on the first and second levels, hydrogen chloride is detected, and the temperature range is 110 - 150 °C; The fourth level, soot is detected, and the temperature range is above 150 °C; The data receiving and processing device processes the data transmitted by the characteristic gas detectors based on the internal early warning model, judges the level of belt fire occurrence, and transmits the alarm information to the regional alarm device and the regional display.

2. The method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 1, characterized in that, The isobaric impact injection tube is powered by a gas source gun with a Laval nozzle diameter of 4 mm, a working pressure of 50 MPa, and a bursting pressure of 80 MPa.

3. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 2, characterized in that, When the isobaric impact injection tube implants the upper and lower covering layers of the belt, the central axis of the isobaric impact injection tube is perpendicular to the belt surface, the nozzle is 1 cm away from the upper and lower covering layers of the belt, and it is implanted once every 20 cm horizontally and 40 cm vertically. The implantation depth is 0.1 - 0.5 mm, and the single-hole implantation amount is 0.1 - 1 g.

4. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 1, characterized in that, The total amount of ammonium bicarbonate powder, selenium bromide powder, and aluminum chloride hexahydrate powder added is 0.1% - 1% of the rubber mass fraction of the belt covering layer.

5. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 1, characterized in that, Each of the above-mentioned characteristic gas detectors can detect the gases generated by the thermal decomposition of the temperature-sensitive material and the changes in their concentrations, and are respectively installed on the downwind side of the intake air in the mine roadway, and are vertically suspended at intervals along the intake air direction above the machine head, 0.3 meters from the roof of the roadway and 0.2 meters from the side wall of the roadway in a straight line.

6. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 1, characterized in that, After receiving the alarm information transmitted, the regional alarm device can display the corresponding belt temperature and gas concentration information, and transmit the early warning information to the mine central control system; the regional display is connected to the regional alarm device, and the coding of the characteristic gas detector that detects the characteristic gas can be displayed on the regional display.

7. A method for warning of a fire in a conveyor belt by implanting a temperature-sensitive material in the conveyor belt according to claim 1, characterized in that, A bus isolator is provided between the power supply bus for connection and the signal bus for transmission in the method for warning of the fire of the conveyor belt, and a fire protection module is also provided on the signal bus.

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