Monitoring System for Coal Spontaneous Combustion in Goaf of Steeply Inclined Thick Coal Seams and Hazard Early Warning Method

Abstract

The present invention relates to the technical field of coal spontaneous combustion monitoring in goafs of steeply inclined thick coal seams, and specifically discloses a coal spontaneous combustion monitoring system and a danger warning method in goafs of steeply inclined thick coal seams. The coal spontaneous combustion monitoring system in goafs of steeply inclined thick coal seams includes: a goaf three-dimensional model construction module, a marking module, a collapse simulation module, a drilling preset calibration module, a sensor layout module and an analysis module. The present application constructs a three-dimensional model of the goaf, surveys the crack position and loose coal body at each layered working face (the horizontal plane formed by layered mining), and performs corresponding collapse simulation. The approximate location of crack leakage is obtained through the collapse simulation. By obtaining the approximate location of crack leakage, the goaf is drilled and sensors are laid to monitor the oxygen concentration, vibration and temperature in the area, so as to achieve accurate warning of spontaneous combustion in goafs of steeply inclined thick coal seams.

Description

Technical Field

[0001] The present invention relates to the technical field of coal spontaneous combustion monitoring in goaf areas, and in particular to a coal spontaneous combustion monitoring system and a danger early warning method in goaf areas of steeply inclined thick coal seams. Background Art

[0002] A steeply inclined coal seam refers to a coal seam with an inclination greater than 45° during underground mining. Due to the large inclination of the coal seam, if the coal seam is thick, the layered mining method is generally adopted. The horizontal goaf formed by layered mining is prone to coal spontaneous combustion accidents, and causes a large amount of thick smoke and intermittent gas explosions, which leads to the closure of the entire mine. Therefore, it is necessary to monitor and control the steeply inclined goaf to prevent the occurrence of the above problems. Summary of the Invention

[0003] In view of this, the object of the present invention is to provide a coal spontaneous combustion monitoring system and a danger warning method for steeply inclined thick coal seam goaf areas.

[0004] The main purpose of the present application is to provide a coal spontaneous combustion monitoring system for the goaf of a steeply inclined thick coal seam, comprising: a goaf 3D model construction module, which obtains on-site 3D scanning data of the goaf of the working face, constructs a 3D coordinate system based on the on-site 3D scanning data of the goaf of the working face, and constructs a 3D model of the goaf based on the constructed 3D coordinate system, and constructs the final mining line boundary of the goaf in the 3D model of the goaf;

[0005] The marking module obtains the crack detection data of the goaf of the working face and marks the coordinate position of the crack location and the loose coal body in the three-dimensional model of the goaf based on the crack detection data;

[0006] The collapse simulation module uses the final mining line boundary, the coordinate position of the loose coal body, and the crack position of the 3D model of the goaf as the simulation benchmark to perform collapse simulation. The 3D model of the goaf is divided into several regional units based on the collapse simulation results. The simulated air leakage channels are delineated in the corresponding regional units based on the collapse results, and the location data of the air leakage channels in the regional units are recorded.

[0007] The drilling preset calibration module sets the preset location for on-site drilling based on the location data of the air leakage channel marked in the area unit, guides on-site drilling based on the location data of the air leakage channel, and drills the hole to the preset location;

[0008] The sensor deployment module deploys sensor modules and transmission nodes according to the drill holes opened on site, and uploads the sensor modules to the host computer through the transmission nodes;

[0009] The analysis module is set inside the host computer and is used to analyze the probability of spontaneous combustion based on the monitoring data of the transmission node received by the host computer.

[0010] Furthermore, when performing on-site three-dimensional scanning of the working face goaf, several positioning marks are arranged on-site in the working face goaf, and geographic coordinates corresponding to the several positioning marks are obtained, and a three-dimensional coordinate system is constructed using the geographic coordinates as a reference.

[0011] Furthermore, the collapse simulation includes the following methods:

[0012] In the three-dimensional model of the goaf, the mining layer boundary of the goaf of the working face is delineated with the boundary of the final mining line as a reference, and the layered working face of the goaf of the working face is delineated with the mining layer boundary;

[0013] Marking the coordinate positions and crack positions of the loose coal body in the layered working surface, then demarcating the loose coal body area and the crack area, and obtaining the corresponding relationship between the crack area and the loose coal body area in the spatial structure;

[0014] Each layered working face is simulated independently, and a destruction coefficient is set for each layered working face during collapse simulation. Then, a force equal to the destruction coefficient is applied from the crack region to the loose coal region to simulate the degree of downward collapse of the loose coal region under different destruction coefficients. According to the degree of downward collapse of the loose coal region, a corresponding simulation is performed on the collapse spatial structure formed by the downward collapse of the loose coal region. Furthermore, the changes in the crack structure caused by the downward collapse of the loose coal region to the associated crack region are simulated, thereby obtaining the first simulation result of each layered working face.

[0015] Alternatively, a simulation analysis is performed using the nonlinear finite element software MSC.Marc, in which the contact relationship between the loose coal regions in different layered working faces is marked, and the positional correlation relationship between the crack regions in different layered working faces is set;

[0016] Taking any crack area in the uppermost layer working surface as the pressure point, different forces within the set range are applied to the uppermost layer working surface. Based on the contact relationship between the loose coal areas in different layer working surfaces, the collapse of the entire goaf is simulated and the collapse range is demarcated.

[0017] The second simulation result is obtained based on the positional correlation between the collapse range and the crack areas in different layered working surfaces.

[0018] Furthermore, when each layered working face is simulated independently, the destruction coefficient of each layered working face collapse simulation is set based on the simulation benchmark that each loose coal area is caused to fall off under natural gravity due to external force.

[0019] Furthermore, the loose coal body regions in different layered working faces and the loose coal body regions in the same layered working face are set as spatial contacts through the contact relationship, and the marked positions of the loose coal body regions in the spatial contacts are recorded;

[0020] Through spatial contact, structural contact is transformed. The volume of the spatial area of the loose coal body in different layered working faces is used as the standard for demarcating the structural blocks. The structural blocks are reconstructed by marking the positions to obtain a structural contact simulation body formed by the structural blocks. The corresponding compression stress coefficient and tension stress coefficient are set according to the volume of the spatial area of each structural block.

[0021] Taking any crack area on the uppermost layered working surface as the pressure point, a force corresponding to the compression stress coefficient and / or the tension stress coefficient is applied to the uppermost layered working surface. Since the positions of the structural contact simulation bodies are correlated with each other in an up-and-down position or in a left-and-right overlapping relationship, when one of the structural blocks collapses and fails, there is a chain failure corresponding to the up-and-down position correlation or the left-and-right overlapping relationship, thereby forming a collapse simulation caused by structural failure, and the corresponding collapse range of the collapse simulation is calibrated.

[0022] Furthermore, based on the first simulation result of each layered working surface, that is, the degree of downward collapse of the loose coal body area under different destruction coefficients and the crack structure changes in the associated crack area caused by the downward collapse of the loose coal body area are used as the first simulation result, each layered working surface is divided into several first area units according to the first simulation result, and the simulated first air leakage channel is delineated in the corresponding first area unit according to each crack structure change, and the first position data of the first air leakage channel in the first area unit is recorded.

[0023] Furthermore, according to the second simulation result, that is: according to the calibrated collapse range of the collapse simulation, the three-dimensional model of the goaf is divided into several second area units, and according to the collapse result, the simulated second air leakage channel is delineated in the corresponding second area unit, and the second position data of the second air leakage channel in the second area unit is recorded.

[0024] Furthermore, the sensor module at least includes:

[0025] Temperature sensors to monitor the temperature of the loose media area;

[0026] Oxygen concentration monitor to monitor the oxygen content in the loose media area;

[0027] A vibration sensor that monitors vibration changes in loose media areas.

[0028] Furthermore, each of the sensor modules is provided with a transmission node.

[0029] The present invention also provides a method for monitoring and warning of coal spontaneous combustion hazards in steeply inclined thick coal seam goafs, including the aforementioned coal spontaneous combustion monitoring system in steeply inclined thick coal seam goafs, which analyzes the probability of spontaneous combustion based on the monitoring data of the transmission node received by the upper computer, and performs monitoring and warning based on the probability of spontaneous combustion.

[0030] Since steeply inclined thick coal seams are mined in layers, this application can monitor coal spontaneous combustion in the goafs formed during mining and after mining. Through a large number of studies, it was found that when the goaf collapses, a large amount of oxygen accumulates in the collapsed area due to the presence of air leakage through the cracks, which is the main cause of fire. Therefore, as long as the side cracks in the roof formed by the impact of the horizontal section caving of the top coal can be effectively explored and the factors that cause the existence of fire can be sorted out, it is possible to accurately monitor the spontaneous combustion of coal in the goafs of steeply inclined thick coal seams.

[0031] This application constructs a three-dimensional model of the goaf, surveys the crack positions and loose coal bodies at each layered working surface (the horizontal plane formed by layered mining), and performs corresponding collapse simulations. The approximate locations of crack leakage are obtained through collapse simulations. By obtaining the approximate locations of crack leakage, holes are drilled in the goaf and sensors are deployed to monitor the oxygen concentration, vibration and temperature in the area, so as to achieve accurate early warning of spontaneous combustion in the goaf of steeply inclined thick coal seams. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of a goaf of a moderately steeply inclined thick coal seam according to the present invention;

[0033] Figure 2 This is a schematic diagram of the system framework of the present invention.

[0034] The numbers and names in the figure correspond to the following: 1. Fire and windproof tunnel; 2. Final mining line; 3. Support roof; 4. Geological fissure; 5. Goaf. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] Reference Figure 1The crack leakage that may exist in the goaf of steeply inclined thick coal seams mainly includes the following two aspects. The first is the roof side crack leakage formed by the influence of horizontal segmented top coal mining; the second is the naturally existing surface cracks and disturbance cracks caused by mining on the geological structure. When the upper multiple layers are mined, the roof surrounding rock bends toward the goaf and moves downward along the layer, and the bottom rock layer bulges toward the goaf and slides down along the layer. As the goaf continues to extend, the upper overburden will fracture and fall. After the coal rock movement stabilizes, the roof rock layer will have collapse zones, fault zones and curved sinking zones, and the bottom plate will have curved sinking zones, resulting in the expansion of roof side crack leakage. At the same time, due to fractures and caving inside the goaf, the disturbance cracks and surface cracks will also expand. When these cracks expand, the oxygen concentration that can enter the goaf will rise sharply. If there is a large amount of air leakage from each layered working face to the surface, the floating coal will reach the necessary conditions (oxygen concentration and temperature) for spontaneous combustion, resulting in fire accidents.

[0037] Figure 1 A schematic diagram of a steeply inclined thick coal seam area with support and backfill in a segmented and multi-layered mining system is provided, wherein a fire and windproof tunnel 1 is used to form a relatively closed fire and windproof area in the mining area, a final mining line 2, a supporting roof 3, a geological fracture 4 and a goaf 5.

[0038] Reference Figure 2 Based on the above, the present application provides a coal spontaneous combustion monitoring system for a steeply inclined thick coal seam goaf, including: a goaf three-dimensional model construction module, which obtains on-site three-dimensional scanning data of the goaf of the working face, constructs a three-dimensional coordinate system based on the on-site three-dimensional scanning data of the goaf of the working face, and constructs a three-dimensional model of the goaf based on the constructed three-dimensional coordinate system, and constructs the final mining line boundary of the goaf in the three-dimensional model of the goaf;

[0039] The marking module obtains the crack detection data of the goaf of the working face and marks the coordinate position of the crack location and the loose coal body in the three-dimensional model of the goaf based on the crack detection data;

[0040] The collapse simulation module uses the final mining line boundary, the coordinate position of the loose coal body, and the crack position of the 3D model of the goaf as the simulation benchmark to perform collapse simulation. The 3D model of the goaf is divided into several regional units based on the collapse simulation results. The simulated air leakage channels are delineated in the corresponding regional units based on the collapse results, and the location data of the air leakage channels in the regional units are recorded.

[0041] The drilling preset calibration module sets the preset location for on-site drilling based on the location data of the air leakage channel marked in the area unit, guides on-site drilling based on the location data of the air leakage channel, and drills the hole to the preset location;

[0042] The sensor deployment module deploys sensor modules and transmission nodes according to the drill holes opened on site, and uploads the sensor modules to the host computer through the transmission nodes;

[0043] The analysis module is set inside the host computer and is used to analyze the probability of spontaneous combustion based on the monitoring data of the transmission node received by the host computer.

[0044] In the above, when performing a three-dimensional scan of the goaf of the working face, several positioning marks are arranged on site in the goaf of the working face, and the geographical coordinates corresponding to the several positioning marks are obtained, and the three-dimensional coordinate system is constructed with the geographical coordinates as a reference. Specifically, a standard coordinate system is established in the three-dimensional software. After the three-dimensional model of the goaf is constructed in the three-dimensional software, the corresponding mark point position is transformed with geographical coordinates. When the entire coordinate system is traversed, the transformation with geographical coordinates can be completed, and the three-dimensional model of the goaf is constructed with geographical coordinates. The roof side cracks and air leakage caused by the horizontal segmented top coal mining, naturally existing surface cracks (which can be surveyed), and disturbance cracks caused by mining on the geological structure (which can be surveyed) can be marked with geographical coordinates. In this way, the positions of different cracks on site can be restored.

[0045] It should be noted that, since this application can monitor the spontaneous combustion of coal in the goaf formed during mining, when layered sealing mining is adopted during the mining process, due to the existence of certain cavities inside the coal seam, coupled with the disturbance formed during the mechanical mining process, the coal seam will experience self-collapse and disturbance collapse. Self-collapse and disturbance collapse generally do not form a chain reaction. In other words, self-collapse and disturbance collapse generally occur in their respective layers. This type of collapse can be explained as a falling collapse under the action of self-weight due to changes in the coal seam structure. Therefore, when performing collapse simulation, each layered working face needs to be simulated independently.

[0046] Reference Figure 1After the mining is completed, support should be placed according to the geological conditions of the coal seam during the actual mining process. Therefore, the residual coal formed in the goaf of different layers may be different. For the loose coal seams in the horizontal coal seams, the required support strength is large. In order to ensure the safe withdrawal of the working face support, the mesh is laid without placing the top coal at a distance of 30m from the final mining line. As the working face advances, the residual coal in the goaf increases exponentially. Moreover, after the coal seam is mined, the originally loose residual coal loses the support of part of the coal body, which will lead to a looser structure. In the goaf of the horizontal layer, there is a large amount of residual coal in the goaf of each upper layer working face, and as the working face is mined, all of it collapses into the goaf of the working face, further increasing the amount of floating coal in the layer. In order to facilitate the support of the roadway, a certain thickness of coal skin is left on the roof and bottom plates of the two roadways and the coal seam. As the working face is mined, this part of the floating coal collapses to the vicinity of the intake and return air roadways in the goaf, and there is also a section of unminable triangular coal on the coal seam bottom plate side of the working face. Therefore, after mining, the goaf may collapse due to inadequate support, which may cause the residual coal inside. Once collapsed, a collapsed space is formed, providing an effective space for oxygen accumulation. Therefore, in the fully mined goaf, structural simulation is required to obtain the final collapse simulation.

[0047] Structural collapse simulation is a complex numerical process of transformation from continuum to discontinuum, which requires the numerical model to not only consider the various behaviors of the structure before collapse, but also reflect the rigid body displacement of structural fragments and the mutual contact and collision between damaged blocks after the destruction of some components. Therefore, the current mainstream structural collapse simulation is to use nonlinear finite element software MSC.Marc for simulation analysis. However, nonlinear finite element software MSC.Marc is mainly used for simulation analysis of building structures. Due to the complex structure of the goaf, and the structure of the goaf does not necessarily have a chain reaction like the building structure, it may exist randomly (for example, the part with full support is difficult to collapse, while the loose part without support is prone to collapse, and due to the complex geological structure of the goaf, the support When setting, the corresponding positions are complex and changeable, some are close to each other, and some are set at intervals, which are closely related to the geological structure of the goaf). Therefore, the present invention sets the loose coal body areas in different layered working surfaces and the loose coal body areas in the same layered working surface as spatial contacts through the contact relationship, records the marked positions of the loose coal body areas in the spatial contacts, and performs structural contact conversion through spatial contacts. The loose coal body areas in different layered working surfaces are used as the standard for demarcating structural blocks based on the volume of the spatial areas, and the structural blocks are reconstructed through the marked positions to obtain a structural contact simulation body formed by the structural blocks. The corresponding compression stress coefficient and tension stress coefficient are set according to the volume of the spatial area of each structural block, which provides the possibility for realizing simulation analysis using the nonlinear finite element software MSC.Marc.

[0048] Specifically, according to the above description, the collapse simulation includes the following methods:

[0049] In the three-dimensional model of the goaf, the mining layer boundary of the goaf of the working face is delineated with the boundary of the final mining line as a reference, and the layered working face of the goaf of the working face is delineated with the mining layer boundary;

[0050] Marking the coordinate positions and crack positions of the loose coal body in the layered working surface, then demarcating the loose coal body area and the crack area, and obtaining the corresponding relationship between the crack area and the loose coal body area in the spatial structure;

[0051] Each layered working surface is taken as an independent simulation, and the destruction coefficient of each layered working surface during collapse simulation is set. Then, a force equal to the destruction coefficient is applied from the crack area to the loose coal body area to simulate the degree of downward collapse of the loose coal body area under different destruction coefficients. According to the degree of downward collapse of the loose coal body area, the collapse spatial structure formed by the downward collapse of the loose coal body area is simulated accordingly, and the crack structure changes caused by the downward collapse of the loose coal body area to the associated crack area are simulated, so as to obtain the first simulation result of each layered working surface.

[0052] In the above, when each layered working face is simulated independently, the destruction coefficient of each layered working face collapse simulation is set based on the simulation benchmark that each loose coal area is caused to fall off under natural gravity by external applied force.

[0053] In the above, based on the first simulation result of each layered working surface, that is, the degree of downward collapse of the loose coal body area under different destruction coefficients and the crack structure changes caused by the downward collapse of the loose coal body area to the associated crack area are taken as the first simulation results, each layered working surface is divided into several first area units according to the first simulation results, and the simulated first air leakage channel is delineated in the corresponding first area unit according to each crack structure change, and the first position data of the first air leakage channel in the first area unit is recorded.

[0054] Specifically, according to the above description, the collapse simulation includes the following methods:

[0055] In the three-dimensional model of the goaf, the mining layer boundary of the goaf of the working face is delineated with the boundary of the final mining line as a reference, and the layered working face of the goaf of the working face is delineated with the mining layer boundary;

[0056] Marking the coordinate positions and crack positions of the loose coal body in the layered working surface, then demarcating the loose coal body area and the crack area, and obtaining the corresponding relationship between the crack area and the loose coal body area in the spatial structure;

[0057] The nonlinear finite element software MSC.Marc was used for simulation analysis. The contact relationship between the loose coal areas in different layered working faces was marked in the nonlinear finite element software MSC.Marc, and the position correlation relationship of the crack areas in different layered working faces was set.

[0058] Taking any crack area in the uppermost layer working surface as the pressure point, different forces within the set range are applied to the uppermost layer working surface. Based on the contact relationship between the loose coal areas in different layer working surfaces, the collapse of the entire goaf is simulated and the collapse range is demarcated.

[0059] The second simulation result is obtained based on the positional correlation between the collapse range and the existence of crack regions in different layered working surfaces.

[0060] In the above, the loose coal body areas in different layered working faces and the loose coal body areas in the same layered working face are set as spatial contacts through the contact relationship, and the marked positions of the loose coal body areas in the spatial contacts are recorded.

[0061] Through spatial contact, structural contact is transformed. The volume of the spatial area of the loose coal body in different layered working faces is used as the standard for demarcating the structural blocks. The structural blocks are reconstructed by marking the positions to obtain a structural contact simulation body formed by the structural blocks. The corresponding compression stress coefficient and tension stress coefficient are set according to the volume of the spatial area of each structural block.

[0062] This application transforms the loose coal area into a three-dimensional model with structural blocks as the main structure by using the volume of the spatial area as the standard for demarcating the structural blocks. This model is similar to a building structure and can directly convert the volume of the spatial area into the compression stress coefficient and the tension stress coefficient for gravity when assigning values. The gravity here can be the approximate weight of the loose coal area.

[0063] Taking any crack area on the uppermost layered working surface as the pressure point, a force corresponding to the compression stress coefficient and / or the tension stress coefficient is applied to the uppermost layered working surface. Since the positions of the structural contact simulation bodies are correlated with each other in an up-and-down position or in a left-and-right overlapping relationship, when one of the structural blocks collapses and fails, there is a chain failure corresponding to the up-and-down position correlation or the left-and-right overlapping relationship, thereby forming a collapse simulation caused by structural failure, and the corresponding collapse range of the collapse simulation is calibrated.

[0064] In the above, according to the second simulation result, that is: according to the calibrated collapse range of the collapse simulation, the three-dimensional model of the goaf is divided into several second area units, and according to the collapse result, the simulated second air leakage channel is delineated in the corresponding second area unit, and the second position data of the second air leakage channel in the second area unit is recorded.

[0065] In the above, this application constructs a three-dimensional model of the goaf, surveys the crack position and loose coal body at each layered working surface (the horizontal plane formed by layered mining), and performs corresponding collapse simulation. The approximate location of the crack leakage is obtained through the collapse simulation. By obtaining the approximate location of the crack leakage, the goaf is drilled and sensors are deployed to monitor the oxygen concentration, vibration and temperature in the area, so as to achieve accurate early warning of spontaneous combustion in the goaf of steeply inclined thick coal seams.

[0066] Furthermore, the sensor module at least includes:

[0067] Temperature sensors to monitor the temperature of the loose media area;

[0068] Oxygen concentration monitor to monitor the oxygen content in the loose media area;

[0069] A vibration sensor that monitors vibration changes in loose media areas.

[0070] Furthermore, each sensor module is provided with a transmission node.

[0071] The present invention also provides a method for monitoring and warning of coal spontaneous combustion hazards in steeply inclined thick coal seam goafs, including the aforementioned coal spontaneous combustion monitoring system in steeply inclined thick coal seam goafs, which analyzes the probability of spontaneous combustion based on the monitoring data of the transmission node received by the upper computer, and performs monitoring and warning based on the probability of spontaneous combustion.

[0072] Since steeply inclined thick coal seams are mined in layers, this application can monitor coal spontaneous combustion in the goafs formed during mining and after mining. Through a large number of studies, it was found that when the goaf collapses, the presence of air leakage in the cracks causes a large amount of oxygen to accumulate in the collapsed area, which is the main cause of fire. Therefore, as long as the side cracks in the roof formed by the impact of the horizontal section caving mining can be effectively explored and the factors that cause fire can be sorted out, it is possible to accurately monitor the spontaneous combustion of coal in the goafs of steeply inclined thick coal seams.

[0073] The above description is only part of the embodiments of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. The coal spontaneous combustion monitoring system in the goaf of steeply inclined thick coal seams is characterized by: include: The goaf 3D model construction module obtains the on-site 3D scanning data of the goaf of the working face, constructs a 3D coordinate system based on the on-site 3D scanning data of the goaf of the working face, and constructs a 3D model of the goaf based on the constructed 3D coordinate system. The final mining line boundary of the goaf is constructed in the 3D model of the goaf; The marking module obtains the crack detection data of the goaf of the working face and marks the coordinate position of the crack location and the loose coal body in the three-dimensional model of the goaf based on the crack detection data; The collapse simulation module uses the final mining line boundary, the coordinate position of the loose coal body, and the crack position of the 3D model of the goaf as the simulation benchmark to perform collapse simulation. The 3D model of the goaf is divided into several regional units based on the collapse simulation results. The simulated air leakage channels are delineated in the corresponding regional units based on the collapse results, and the location data of the air leakage channels in the regional units are recorded. The drilling preset calibration module sets the preset location for on-site drilling based on the location data of the air leakage channel marked in the area unit, guides on-site drilling based on the location data of the air leakage channel, and drills the hole to the preset location; The sensor deployment module deploys sensor modules and transmission nodes according to the drill holes opened on site, and uploads the sensor modules to the host computer through the transmission nodes; An analysis module is provided inside the host computer and is used to analyze the probability of spontaneous combustion based on the monitoring data of the transmission node received by the host computer; Collapse simulation includes the following methods: In the three-dimensional model of the goaf, the mining layer boundary of the goaf of the working face is delineated with the boundary of the final mining line as a reference, and the layered working face of the goaf of the working face is delineated with the mining layer boundary; Marking the coordinate positions and crack positions of the loose coal body in the layered working surface, then demarcating the loose coal body area and the crack area, and obtaining the corresponding relationship between the crack area and the loose coal body area in the spatial structure; Each layered working face is simulated independently, and a destruction coefficient is set for each layered working face during collapse simulation. Then, a force equal to the destruction coefficient is applied from the crack region to the loose coal region to simulate the degree of downward collapse of the loose coal region under different destruction coefficients. According to the degree of downward collapse of the loose coal region, a corresponding simulation is performed on the collapse spatial structure formed by the downward collapse of the loose coal region. Furthermore, the changes in the crack structure caused by the downward collapse of the loose coal region to the associated crack region are simulated, thereby obtaining the first simulation result of each layered working face. Alternatively, a simulation analysis is performed using the nonlinear finite element software MSC.Marc, in which the contact relationship between the loose coal regions in different layered working faces is marked, and the positional correlation relationship between the crack regions in different layered working faces is set; Taking any crack area in the uppermost layer working surface as the pressure point, different forces within the set range are applied to the uppermost layer working surface. Based on the contact relationship between the loose coal areas in different layer working surfaces, the collapse of the entire goaf is simulated and the collapse range is demarcated. The second simulation result is obtained based on the positional correlation between the collapse range and the crack areas in different layered working surfaces.

2. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: When performing on-site three-dimensional scanning of the goaf of the working face, several positioning marks are arranged on-site in the goaf of the working face, and geographic coordinates corresponding to the several positioning marks are obtained, and a three-dimensional coordinate system is constructed using the geographic coordinates as a reference.

3. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: When each layered working face is simulated independently, the destruction coefficient of each layered working face collapse simulation is set based on the simulation benchmark of each loose coal area falling off under natural gravity due to external force.

4. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: The loose coal body regions in different layered working faces and the loose coal body regions in the same layered working face are set as spatial contacts according to the contact relationship, and the marked positions of the loose coal body regions in the spatial contacts are recorded; Through spatial contact, structural contact is transformed. The volume of the spatial area of the loose coal body in different layered working faces is used as the standard for demarcating the structural blocks. The structural blocks are reconstructed by marking the positions to obtain a structural contact simulation body formed by the structural blocks. The corresponding compression stress coefficient and tension stress coefficient are set according to the volume of the spatial area of each structural block. Taking any crack area on the uppermost layered working surface as the pressure point, a force corresponding to the compression stress coefficient and / or the tension stress coefficient is applied to the uppermost layered working surface. Since the positions of the structural contact simulation bodies are correlated with each other in an up-and-down position or in a left-and-right overlapping relationship, when one of the structural blocks collapses and fails, there is a chain failure corresponding to the up-and-down position correlation or the left-and-right overlapping relationship, thereby forming a collapse simulation caused by structural failure, and the corresponding collapse range of the collapse simulation is calibrated.

5. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: According to the first simulation result of each layered working surface, that is, the degree of downward collapse of the loose coal body area under different destruction coefficients and the crack structure changes of the associated crack area caused by the downward collapse of the loose coal body area are used as the first simulation result, each layered working surface is divided into several first area units according to the first simulation result, and the simulated first air leakage channel is delineated in the corresponding first area unit according to each crack structure change, and the first position data of the first air leakage channel in the first area unit is recorded.

6. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: According to the second simulation result, that is: according to the calibrated collapse range of the collapse simulation, the three-dimensional model of the goaf is divided into several second area units, and according to the collapse result, the simulated second air leakage channel is delineated in the corresponding second area unit, and the second position data of the second air leakage channel in the second area unit is recorded.

7. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: The sensor module at least includes: Temperature sensors to monitor the temperature of the loose media area; Oxygen concentration monitor to monitor the oxygen content in the loose media area; A vibration sensor that monitors vibration changes in loose media areas.

8. The coal spontaneous combustion monitoring system for steeply inclined thick coal seam goaf according to claim 1 is characterized in that: Each of the sensor modules is provided with a transmission node.

9. A method for monitoring and warning of coal spontaneous combustion danger in a steeply inclined thick coal seam goaf, comprising any one of the coal spontaneous combustion monitoring systems in a steeply inclined thick coal seam goaf according to claims 1-8, characterized in that: The probability of spontaneous combustion is analyzed based on the monitoring data of the transmission node received by the host computer, and monitoring and early warning are carried out based on the probability of spontaneous combustion.

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