System and method for monitoring spontaneous combustion of underground working face

Abstract

The invention provides an underground working face spontaneous combustion monitoring system and method.The underground working face spontaneous combustion monitoring method comprises the steps that (1) a target area is divided to determine monitoring points and strain points, and first wireless sensor nodes and second wireless sensor nodes are deployed respectively; (2) acquiring the environment temperature and the combustible gas concentration of each monitoring point on line through a first wireless sensor node, and comparing and analyzing the acquired real-time data and a preset critical value to determine a dangerous area; (3) monitoring the temperature change and the combustible gas concentration change of the dangerous area within the preset time for visual display, and judging whether a fire risk exists in the dangerous area or not; and (IV) waking up the second wireless sensor nodes deployed at the strain points around the dangerous area, evaluating the fire hazard grade, and carrying out graded early warning. According to the method, the monitoring data of the underground working face is comprehensively analyzed, the spontaneous combustion risk is evaluated and graded early warning is performed, and the detection accuracy is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mine fire prevention, and relates to a spontaneous combustion monitoring system and method for an underground working face. Background Art

[0002] At present, most fires in coal mines are caused by spontaneous combustion of coal mines. The combustion is hidden and accompanied by harmful gases, gas explosions and other hidden dangers during the combustion process, which seriously threatens the safety of workers and mining equipment. In order to reduce safety risks, a large number of coal mine spontaneous combustion monitoring systems have emerged. In actual use, different sensors are often used to detect and analyze data such as ambient temperature, gas concentration and smoke when a fire occurs in a coal mine, so as to provide fire warning.

[0003] CN215954447U discloses a mine fire risk monitoring and early warning system, including: a mine coal spontaneous combustion fire risk monitoring and early warning subsystem extracts gas from the goaf through a beam tube, uses a tunable semiconductor laser to analyze the gas composition and various gas concentrations, thereby judging the gas temperature range of the goaf and determining the risk warning level; a mine external fire risk monitoring and early warning subsystem monitors whether underground equipment ignites and produces smoke through a smoke sensor, and monitors the flame through video and image processing; and realizes accurate early warning of the mine external fire risk through monitoring of temperature, gas, mine cables, belts and electromechanical equipment. The system integrates the coal spontaneous combustion disaster in the goaf and the external fire risk warning, realizes the organic integration of monitoring means such as the beam tube monitoring system, video monitoring system, temperature monitoring system, and smoke monitoring system, so that the data of each system can be interconnected and integrated.

[0004] CN203658303U discloses a novel mine safety monitoring system with a coal spontaneous combustion monitoring function, including an ethylene gas detection chassis, wherein a No. 1 electric vacuum pump, a No. 1 desiccant tank, a precious metal catalyst tank, and an ethylene sensor are installed in the box of the ethylene gas detection chassis, the air inlet end of the precious metal catalyst tank is directly connected to the internal space of the box, the air outlet end of the precious metal catalyst tank is connected to the air inlet end of the ethylene sensor, the air outlet end of the No. 1 electric vacuum pump is connected to the air inlet end of the No. 1 desiccant tank, the air outlet end of the No. 1 desiccant tank is directly connected to the internal space of the box, the air inlet end of the No. 1 electric vacuum pump is connected to the air inlet pipe joint, the No. 1 air inlet pipe joint is connected to the No. 1 ventilation pipeline, and the No. 1 ventilation pipeline is connected to the extension pipe outside the box. The system performs real-time and effective monitoring of the gas in the detection area through gas sampling, with high monitoring accuracy and low maintenance cost, so that the monitoring of the characteristic gas of coal spontaneous combustion is realized informatization and automation.

[0005] However, in actual application, the existing spontaneous combustion monitoring system is subject to the constraints of the complex environment of the mine and the limitations of production operation requirements, and is easily interfered with, resulting in reduced detection accuracy. At the same time, traditional monitoring and early warning methods require manual intervention, and have problems such as slow response speed and untimely early warning. It is also impossible to accurately classify the danger level of coal spontaneous combustion. In addition, the data transmission of some systems is unstable, and the data is single and comprehensive. It is also impossible to accurately confirm the location of the fire area, resulting in delayed early warning guidance and certain safety hazards. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a system and method for monitoring spontaneous combustion of underground working faces. By comprehensively analyzing the monitoring data of the underground working faces, the risk of spontaneous combustion is evaluated and graded warnings are issued, thereby improving the detection accuracy and reducing the risk of misjudgment and wrong judgment.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for monitoring spontaneous combustion of an underground working surface, the method comprising:

[0009] (I) dividing the target area to determine a number of monitoring points, and deploying a first wireless sensor node at each monitoring point to form a data collection network, and at the same time dividing a number of strain points around the monitoring point according to a preset distance, and deploying a second wireless sensor node at each strain point;

[0010] (II) The ambient temperature and combustible gas concentration of each monitoring point are collected online through the first wireless sensor node, and uploaded to the well monitoring terminal, and the collected real-time data are compared and analyzed with the preset critical value to determine the danger zone;

[0011] (III) monitor the temperature change and the combustible gas concentration change in the danger zone within a preset time and display them visually, and determine whether there is a fire risk in the danger zone. If there is a fire risk, execute step (IV); otherwise, return to execute step (II);

[0012] (IV) Wake up the second wireless sensor nodes deployed at each strain point around the danger zone to monitor the oxygen concentration, air pressure and wind speed around the monitoring point, evaluate the fire level, and issue graded warnings.

[0013] As a preferred technical solution of the present invention, in step (I), the number and location of monitoring points are confirmed based on basic data such as spontaneous combustion characteristics, coal seam characteristics, ventilation characteristics, and operating equipment deployment in the target area, and four centrally symmetrical strain points are set on the periphery of each monitoring point with the monitoring point as the center and a preset distance as the radius.

[0014] The present invention comprehensively analyzes various geological characteristics, working forms and environmental conditions in the target area, and then adjusts the number, distance and concentration of monitoring points to ensure comprehensive underground monitoring, which is beneficial to improving the reliability of monitoring work, reducing operating costs, and effectively reducing investment in spontaneous combustion monitoring and fire extinguishing.

[0015] As a preferred technical solution of the present invention, in step (II), with the monitoring point as the center, the area of ​​the danger zone is 1.25 to 3 times the detection surface formed by a number of strain points around the monitoring point. For example, it can be 1.25 times, 1.5 times, 2 times, 2.25 times, 2.5 times, 2.6 times, 2.65 times, 2.7 times, 2.8 times or 3 times, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] As a preferred technical solution of the present invention, in step (II), the combustible gas includes any one of carbon monoxide, methane, propane, ethylene, ethane, acetylene or hydrogen sulfide, or a combination of at least two of them.

[0017] As a preferred technical solution of the present invention, in step (III), a visual temperature distribution map is established based on the deployment position of the first wireless sensor node at each monitoring point in the target area, and a visual temperature dynamic change map is formed using image processing technology.

[0018] At the same time, the image processing technology based on deep learning is used to analyze the combustible gas concentration collected by the first wireless sensor node, and a visual gas dynamic change graph is formed according to the trend of the combustible gas concentration change.

[0019] In the present invention, both the first wireless sensor node and the second wireless sensor node have a positioning function, and the monitoring data of the monitoring point are visualized and dynamically displayed through the well monitoring terminal, which is convenient for the staff to accurately grasp the changes in the monitoring data and predict the fire spread trend.

[0020] As a preferred technical solution of the present invention, in step (III), the process of determining whether there is a fire risk in the danger zone includes the following sub-steps:

[0021] 101: preset temperature change threshold and concentration change threshold;

[0022] 102: Calculate the temperature change rate and the concentration change rate within the preset time interval monitored by the first sensor node respectively;

[0023] 103: Compare the temperature change rate with the temperature change threshold, and the concentration change rate with the concentration change threshold, and when the temperature change rate and / or the concentration change threshold exceeds the corresponding change threshold, determine that there is a fire risk in the danger zone.

[0024] The present invention compares the real-time monitoring data with the critical value and comprehensively considers the change rate of the reference data, so as to more accurately judge the fire risk at the monitoring point, greatly reduce the possibility of misjudgment or wrong judgment, and improve the efficiency of monitoring work.

[0025] As a preferred technical solution of the present invention, in step (IV), the process of evaluating the fire level includes the following sub-steps:

[0026] 201: Obtain oxygen concentration data, air pressure data and wind speed data at different strain points located around the monitoring point in real time;

[0027] 202: Preset the first, second and third warning values ​​of oxygen concentration, air pressure and wind speed;

[0028] 203: Compare the real-time oxygen concentration data with the three warning values, the real-time air pressure data with the three warning values, and the real-time wind speed data with the three warning values, respectively, comprehensively determine the fire level, and determine the fire spreading speed and direction based on the differences in oxygen concentration, air pressure and wind speed at different strain points.

[0029] In a second aspect, the present invention provides a system for monitoring spontaneous combustion of an underground working surface, which is used for the method for monitoring spontaneous combustion of an underground working surface in the first aspect, and comprises a data acquisition unit, a data transmission unit and an uphole monitoring terminal, wherein the data transmission unit is respectively communicatively connected to the data acquisition unit and the uphole monitoring terminal; the data acquisition unit comprises a plurality of first wireless sensor nodes, a plurality of second wireless sensor nodes and a plurality of monitoring base stations, wherein the monitoring base stations are respectively communicatively connected to the first wireless sensor nodes and the second wireless sensor nodes; the data transmission unit comprises an Ethernet ring network, a first switching device and a second switching device, wherein the first switching device and the second switching device are independently connected to the Ethernet ring network, the first switching device is communicatively connected to the monitoring base station, and the second switching device is communicatively connected to the uphole monitoring terminal; the uphole monitoring terminal is provided with a data processing module, a graphics processing module, a visualization interface, a spontaneous combustion risk assessment module and a graded warning module, wherein the graphics processing module is respectively electrically connected to the data processing module and the visualization interface, and the spontaneous combustion risk assessment module is respectively electrically connected to the data processing module and the graded warning module.

[0030] As a preferred technical solution of the present invention, the first wireless sensor node includes a temperature sensor and a combustible gas concentration sensor; the second wireless sensor node includes an oxygen concentration sensor, an air pressure sensor and a wind speed sensor.

[0031] As a preferred technical solution of the present invention, the hierarchical warning module includes a primary alarm component, a secondary alarm component and a tertiary alarm component.

[0032] The system refers to an equipment system, a device system or a production device.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The present invention provides a system and method for monitoring spontaneous combustion of an underground working face, which reasonably divides the target area of ​​the working face to realize zone monitoring, improves the efficiency of spontaneous combustion monitoring, and ensures the safety of underground operations; by first comparing and analyzing the real-time monitoring data of the monitoring point with the preset critical value, and then judging the change state of the monitoring data, a comprehensive judgment is made on the dangerous area where the fire risk exists, thereby improving the accuracy of the monitoring work and reducing the risk of misjudgment or wrong judgment; finally, the environmental monitoring data of the strain points around the monitoring point are used to predict the development trend of the fire, comprehensively evaluate the risk level, and conduct graded early warning, thereby improving the timeliness and accuracy of spontaneous combustion monitoring so that the staff can quickly implement corresponding measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic structural diagram of an underground working face spontaneous combustion monitoring system provided for a specific embodiment of the present invention.

[0036] Figure 2 A schematic structural diagram of a first wireless sensor node and a second wireless sensor node provided in a specific embodiment of the present invention.

[0037] Among them, 100-monitoring point; 200-strain point; 1-first wireless sensor node; 101-temperature sensor; 102-combustible gas concentration sensor; 2-second wireless sensor node; 201-oxygen concentration sensor; 202-air pressure sensor; 203-wind speed sensor; 3-monitoring base station; 4-Ethernet ring network; 5-first switching device; 6-second switching device; 7-data processing module; 8-graphics processing module; 9-visualization interface; 10-spontaneous combustion risk assessment module; 11-graded early warning module; 111-first level alarm component; 112-second level alarm component; 113-third level alarm component. DETAILED DESCRIPTION

[0038] It should be understood that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0039] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0040] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0041] In a specific embodiment, the present invention provides a method for monitoring spontaneous combustion of an underground working surface, the method comprising:

[0042] Step (I): Divide the target area into several monitoring points, and deploy a first wireless sensor node at each monitoring point to form a data acquisition network. At the same time, divide several strain points around the monitoring point according to a preset distance, and deploy a second wireless sensor node at each strain point.

[0043] According to the basic data such as spontaneous combustion characteristics, coal seam characteristics, ventilation characteristics, and operation equipment deployment in the target area, the number and position of the monitoring points are confirmed, and four strain points with central symmetry are set on the periphery of each monitoring point with the monitoring point as the center and the preset distance as the radius. Due to the differences in geological conditions, physical conditions and environmental conditions at different positions in the target area, the spontaneous combustion tendency of different areas is also different. According to the different ignition characteristics, the present invention can divide the target area into flammable areas, spontaneous combustion areas and non-self-ignition areas in the order of gradually complex spontaneous combustion tendencies. Those skilled in the art can adjust the density and distance of the monitoring points according to different areas. The coverage of the target area of ​​the coal mine is relatively wide, and the depth of the coal seam at different positions, the type of coal and its component content and calorific value are different, so that there are differences in the difficulty of spontaneous combustion. The present invention divides the monitoring points according to the characteristics of the coal seam, which can timely discover spontaneous combustion accidents and reduce losses. The ventilation system of the coal mine can continuously send fresh air from the ground into the mine, and discharge the dirty air in the mine to the ground, to ensure the safe operation of underground operations, and play a very important role when a combustion accident occurs underground. The present invention can adjust the position of the monitoring point according to the air volume and air pressure of the ventilation system in the target area, thereby improving the monitoring efficiency and reducing the equipment cost. Since the number, type, material and operation strategy of the operating equipment used in different working modes in the target area are different, the present invention needs to adjust the position of the monitoring point according to the actual operation situation.

[0044] Step (II): The ambient temperature and combustible gas concentration of each monitoring point are collected online through the first wireless sensor node, and uploaded to the well monitoring terminal. The collected real-time data are compared and analyzed with the preset critical value to determine the danger zone.

[0045] The present invention locates the first wireless sensor node of each monitoring point, numbers the monitoring points in sequence, and collects the real-time ambient temperature data and combustible gas concentration data of different monitoring points. When the real-time ambient temperature data and / or combustible gas concentration data of any monitoring point reaches the preset critical value in the well monitoring terminal, the area is judged to be a danger zone. Among them, the present invention takes the monitoring point as the center, and the area of ​​the danger zone is 1.25 to 3 times the detection surface formed by several strain points around the periphery of the monitoring point, that is, the division of the danger zone needs to cover multiple strain points around the monitoring point.

[0046] The combustible gas includes any one of carbon monoxide, methane, propane, ethylene, ethane, acetylene or hydrogen sulfide, or a combination of at least two of them. According to the environmental characteristics of the target area, the present invention can select a single combustible gas type as the analysis object, such as carbon monoxide, methane, propane, ethylene, ethane, acetylene or hydrogen sulfide; it can also use multiple combustible gas types as the analysis object, such as a combination of carbon monoxide, methane and propane, a combination of carbon monoxide, methane and hydrogen sulfide, methane, ethylene and hydrogen sulfide, etc. It is preferred to use multiple combustible gas types as the analysis object for comprehensive analysis to improve the accuracy of monitoring work.

[0047] Step (III): Monitor the temperature change and the combustible gas concentration change in the danger zone within a preset time and display them visually, and determine whether there is a fire risk in the danger zone. If there is a fire risk, execute step (IV); otherwise, return to execute step (II).

[0048] As the operation progresses in the target area, the ambient temperature and the combustible gas concentration at the monitoring point change in real time. The present invention establishes a visual temperature distribution map based on the deployment position of the first wireless sensor node at each monitoring point in the target area, and uses image processing technology to form a visual temperature dynamic change map. The image processing technology is a commonly used processing technology in this field, and the temperature change dynamic map can be produced using image software or web technology familiar to those skilled in the art. At the same time, the image processing technology based on deep learning analyzes the combustible gas concentration collected by the first wireless sensor node, and forms a visual gas dynamic change map based on the trend of the combustible gas concentration change. The present invention conducts a comprehensive analysis by combining the existing deep learning model with the commonly used image processing technology in this field, and establishes a gas dynamic change map to display the changes in the combustible gas concentration at the monitoring point in real time and intuitively.

[0049] In some embodiments, the process of determining whether there is a fire risk in the danger zone includes the following sub-steps:

[0050] 101: preset temperature change threshold and concentration change threshold;

[0051] 102: Calculate the temperature change rate and the concentration change rate within the preset time interval monitored by the first sensor node respectively;

[0052] 103: Compare the temperature change rate with the temperature change threshold, and the concentration change rate with the concentration change threshold, and when the temperature change rate and / or the concentration change threshold exceeds the corresponding change threshold, determine that there is a fire risk in the danger zone.

[0053] Step (IV): Wake up the second wireless sensor nodes deployed at each strain point around the danger zone, monitor the oxygen concentration, air pressure and wind speed around the monitoring point, evaluate the fire level, and issue a graded warning.

[0054] The present invention locates the second wireless sensor nodes around each monitoring point. After determining that there is a risk of spontaneous combustion in the danger zone, the second wireless sensor node is remotely controlled to be awakened and corresponding environmental data information is collected through software, hardware and electromechanical control technologies well known to those skilled in the art. The second wireless sensor node is in a dormant state during the rest of the time.

[0055] The process of evaluating the fire level in the present invention includes the following sub-steps:

[0056] 201: Obtain oxygen concentration data, air pressure data and wind speed data at different strain points located around the monitoring point in real time;

[0057] 202: Preset the first, second and third warning values ​​of oxygen concentration, air pressure and wind speed;

[0058] 203: Compare the real-time oxygen concentration data with the three warning values, the real-time air pressure data with the three warning values, and the real-time wind speed data with the three warning values, respectively, comprehensively determine the fire level, and determine the fire spreading speed and direction based on the differences in oxygen concentration, air pressure and wind speed at different strain points.

[0059] The hierarchical warning in the present invention is divided into three-level warning, two-level warning and one-level warning according to the order of increasing danger degree.

[0060] When the real-time oxygen concentration data reaches the third-level warning value, the danger level is judged to be mild, and a third-level warning is issued; when the real-time oxygen concentration data exceeds the third-level warning value and reaches the second-level warning value, the danger level is judged to be moderate, and a second-level warning is issued; when the real-time oxygen concentration data exceeds the second-level warning value and reaches the first-level warning value, the danger level is judged to be severe, and a first-level warning is issued.

[0061] When the real-time air pressure data reaches the third-level warning value, the danger level is judged to be mild, and a third-level warning is issued; when the real-time air pressure data exceeds the third-level warning value and reaches the second-level warning value, the danger level is judged to be moderate, and a second-level warning is issued; when the real-time air pressure data exceeds the second-level warning value and reaches the first-level warning value, the danger level is judged to be severe, and a first-level warning is issued.

[0062] When the real-time wind speed data reaches the third-level warning value, the danger level is judged to be mild and a third-level warning is issued; when the real-time wind speed data exceeds the third-level warning value and reaches the second-level warning value, the danger level is judged to be moderate and a second-level warning is issued; when the real-time wind speed data exceeds the second-level warning value and reaches the first-level warning value, the danger level is judged to be severe and a first-level warning is issued.

[0063] It should be noted that when the warning levels of the real-time oxygen concentration data, the real-time air pressure data and the real-time wind speed data are different, a warning is issued in the form with the highest danger level.

[0064] In another specific embodiment, the present invention provides a system for monitoring spontaneous combustion of an underground working surface, which is used for a method for monitoring spontaneous combustion of an underground working surface provided in a specific embodiment. The system includes a data acquisition unit, a data transmission unit and an uphole monitoring terminal, and the data transmission unit is communicatively connected to the data acquisition unit and the uphole monitoring terminal respectively.

[0065] like Figure 1 and Figure 2 As shown, the data acquisition unit includes a plurality of first wireless sensor nodes 1, a plurality of second wireless sensor nodes 2 and a plurality of monitoring base stations 3. The first wireless sensor node 1 is set at a monitoring point 100 in the target area, and the second wireless sensor node 2 is set at a strain point 200 surrounding the monitoring point 100. The monitoring base station 3 is respectively connected to the first wireless sensor node 1 and the second wireless sensor node 2 for communication, and is used to receive and summarize the relevant data information of each monitoring point 100 collected by the first wireless sensor node 1 and the second wireless sensor node 2. Specifically, the first wireless sensor node 1 includes a temperature sensor 101 and a combustible gas concentration sensor 102, and the second wireless sensor node 2 includes an oxygen concentration sensor 201, an air pressure sensor 202 and a wind speed sensor 203.

[0066] The data transmission unit includes an Ethernet ring network 4, a first switching device 5 and a second switching device 6. The first switching device 5 and the second switching device 6 are independently connected to the Ethernet ring network 4. The first switching device 5 is arranged underground and is communicatively connected to the monitoring base station 3. The second switching device 6 is arranged above the well and is communicatively connected to the monitoring terminal above the well. Various data information acquired by the data acquisition unit is wirelessly uploaded to the monitoring terminal above the well through the Ethernet ring network 4, the first switching device 5 and the second switching device 6.

[0067] The above-ground monitoring terminal is used as a terminal for operation and monitoring by maintenance personnel in the coal mine. It establishes a complete communication network in the entire inspection area, realizes two-way data interaction, and performs comprehensive analysis and processing on the collected data information. The above-ground monitoring terminal is provided with a data processing module 7, a graphic processing module 8, a visualization interface 9, a spontaneous combustion risk assessment module 10 and a graded warning module 11.

[0068] The data processing module 7 is used to receive, convert and process the data information uploaded by the data transmission unit, and may include general or special input components, such as a keyboard, a mouse, etc.; output components, such as various types of displays, speakers, etc.; storage components, such as memories, optical disks, etc.; and communication components, such as a network card, a modem, a wireless communication transceiver, etc.

[0069] The graphic processing module 8 is electrically connected to the data processing module 7 and the visualization interface 9 respectively, and is used to generate a temperature dynamic change graph and a gas dynamic change graph from the data information processed by the data processing module 7 using image processing technology familiar to those skilled in the art, and display them through the visualization interface 9.

[0070] The spontaneous combustion risk assessment module 10 is electrically connected to the data processing module 7 and the graded warning module 11, respectively, and is used to calculate, analyze and compare various data information processed by the data processing module 7, thereby evaluating the spontaneous combustion level of the dangerous area, and triggering the graded warning module 11 to output different warning states according to different spontaneous combustion level results. The spontaneous combustion risk assessment module 10 is preset with a temperature critical value, a gas concentration critical value, an interval time, a temperature change threshold value and a concentration change threshold value. During use, the collected real-time data is first compared and analyzed with the preset critical value to determine the dangerous area, and then the temperature change rate and the concentration change rate within the preset interval time monitored by the first sensor node are calculated respectively, and the temperature change rate and the temperature change threshold value, as well as the concentration change rate and the concentration change threshold value are compared to determine whether there is a fire risk in the dangerous area. When the spontaneous combustion risk assessment module 10 determines that there is a fire risk in the dangerous area, the second wireless sensor node 2 deployed at each strain point 200 is remotely awakened for data collection. The second wireless sensor node 2 transmits the acquired data information to the monitoring base station 3, and then uploads it to the data processing module 7 for processing through the data transmission module, and the processed data information is then transmitted to the spontaneous combustion risk assessment module 10. The spontaneous combustion risk assessment module 10 is preset with the first-level warning value, the second-level warning value and the third-level warning value of oxygen concentration, air pressure and wind speed. By comparing the real-time oxygen concentration data with the three warning values, the real-time air pressure data with the three warning values, and the real-time wind speed data with the three warning values, the fire level is comprehensively determined, and the fire diffusion speed and direction are determined according to the differences in oxygen concentration, air pressure and wind speed at different strain points 200. The spontaneous combustion risk assessment module 10 may include various general and / or special processing components with processing and computing capabilities, such as various special artificial intelligence computing chips, various processors running machine learning model algorithms, digital signal processors, and any appropriate processors, controllers, microcontrollers, etc.

[0071] The graded warning module 11 includes a primary alarm component 111, a secondary alarm component 112 and a tertiary alarm component 113. The alarm component may be an audible and visual alarm or a voice announcer, which can output different sound signals or light signals of different colors according to different spontaneous combustion levels.

[0072] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for monitoring spontaneous combustion of an underground working face, characterized in that: The underground working face spontaneous combustion monitoring method comprises: (I) dividing the target area to determine a number of monitoring points, and deploying a first wireless sensor node at each monitoring point to form a data collection network, and at the same time dividing a number of strain points around the monitoring point according to a preset distance, and deploying a second wireless sensor node at each strain point; (II) The ambient temperature and combustible gas concentration of each monitoring point are collected online through the first wireless sensor node, and uploaded to the well monitoring terminal, and the collected real-time data are compared and analyzed with the preset critical value to determine the danger zone; (III) monitor the temperature change and the combustible gas concentration change in the danger zone within a preset time and display them visually, and determine whether there is a fire risk in the danger zone. If there is a fire risk, execute step (IV); otherwise, return to execute step (II); (IV) Wake up the second wireless sensor nodes deployed at each strain point around the danger zone to monitor the oxygen concentration, air pressure and wind speed around the monitoring point, evaluate the fire level, and issue graded warnings.

2. The method for monitoring spontaneous combustion of underground working face according to claim 1, characterized in that: In step (I), the number and location of monitoring points are confirmed based on basic data such as spontaneous combustion characteristics, coal seam characteristics, ventilation characteristics, and operating equipment deployment in the target area, and four centrally symmetrical strain points are set on the periphery of each monitoring point with the monitoring point as the center and the preset distance as the radius.

3. The method for monitoring spontaneous combustion of underground working face according to claim 1 or 2, characterized in that: In step (II), with the monitoring point as the center, the area of ​​the danger zone is 1.25 to 3 times the detection surface formed by a number of strain points surrounding the monitoring point.

4. The method for monitoring spontaneous combustion of underground working surface according to claim 1, characterized in that: In step (II), the combustible gas concentration includes the combustible gas including any one of carbon monoxide, methane, propane, ethylene, ethane, acetylene or hydrogen sulfide, or a combination of at least two thereof.

5. The method for monitoring spontaneous combustion of underground working surface according to claim 1, characterized in that: In step (III), based on the deployment position of the first wireless sensor node at each monitoring point in the target area, a visual temperature distribution map is established, and a visual temperature dynamic change map is formed by using image processing technology; At the same time, the image processing technology based on deep learning is used to analyze the combustible gas concentration collected by the first wireless sensor node, and a visual gas dynamic change graph is formed according to the trend of the combustible gas concentration change.

6. The method for monitoring spontaneous combustion of underground working surface according to claim 1, characterized in that: In step (III), the process of determining whether there is a fire risk in the danger zone includes the following sub-steps: 101: preset temperature change threshold and concentration change threshold; 102: Calculate the temperature change rate and the concentration change rate within the preset time interval monitored by the first sensor node respectively; 103: Compare the temperature change rate with the temperature change threshold, and the concentration change rate with the concentration change threshold, and when the temperature change rate and / or the concentration change threshold exceeds the corresponding change threshold, determine that there is a fire risk in the danger zone.

7. The method for monitoring spontaneous combustion of underground working surface according to claim 1, characterized in that: In step (IV), the process of assessing the fire level includes the following sub-steps: 201: Obtain oxygen concentration data, air pressure data and wind speed data at different strain points located around the monitoring point in real time; 202: Preset the first, second and third warning values ​​of oxygen concentration, air pressure and wind speed; 203: Compare the real-time oxygen concentration data with the three warning values, the real-time air pressure data with the three warning values, and the real-time wind speed data with the three warning values, respectively, comprehensively determine the fire level, and determine the fire spreading speed and direction based on the differences in oxygen concentration, air pressure and wind speed at different strain points.

8. A spontaneous combustion monitoring system for underground working faces, characterized in that: The underground working surface spontaneous combustion monitoring system is used for the underground working surface spontaneous combustion monitoring method according to any one of claims 1 to 7, and the underground working surface spontaneous combustion monitoring system comprises a data acquisition unit, a data transmission unit and an uphole monitoring terminal, and the data transmission unit is respectively connected to the data acquisition unit and the uphole monitoring terminal for communication; The data acquisition unit includes a plurality of first wireless sensor nodes, a plurality of second wireless sensor nodes and a plurality of monitoring base stations, wherein the monitoring base stations are respectively connected to the first wireless sensor nodes and the second wireless sensor nodes for communication; The data transmission unit includes an Ethernet ring network, a first switching device and a second switching device, the first switching device and the second switching device are independently connected to the Ethernet ring network, the first switching device is communicatively connected to the monitoring base station, and the second switching device is communicatively connected to the well monitoring terminal; The uphole monitoring terminal is provided with a data processing module, a graphics processing module, a visualization interface, a spontaneous combustion risk assessment module and a graded warning module. The graphics processing module is electrically connected to the data processing module and the visualization interface, respectively, and the spontaneous combustion risk assessment module is electrically connected to the data processing module and the graded warning module, respectively.

9. The underground working face spontaneous combustion monitoring system according to claim 8, characterized in that: The first wireless sensor node includes a temperature sensor and a combustible gas concentration sensor; The second wireless sensor node includes an oxygen concentration sensor, an air pressure sensor and a wind speed sensor.

10. The underground working face spontaneous combustion monitoring system according to claim 8 or 9, characterized in that: The hierarchical warning module includes a first-level alarm component, a second-level alarm component and a third-level alarm component.

Images