A roadway gas scanning detection method and device

Abstract

The application discloses a kind of roadway gas scanning detection method and equipment, belong to coal mine roadway safety monitoring technical field.The method is at least two gas scanning detection equipment in the roadway to be detected, establishes roadway space coordinate system, control each equipment according to preset scanning azimuth angle and scanning pitch angle scanning, obtains the gas concentration data on corresponding scanning path by laser methane remote sensing module or open light path methane detection module, and scanning angle, scanning distance and equipment position data are synchronously obtained;According to the above data, determine scanning path, the scanning path of different equipment is matched in space, obtains roadway gas effective detection point;Effective detection point is mapped to roadway space grid model, forms gas concentration space distribution model, and identifies gas abnormal accumulation area and outputs alarm information.The application can improve roadway gas detection coverage and abnormal identification ability.

Description

Technical Field

[0001] This invention belongs to the field of coal mine roadway safety monitoring technology, specifically relating to a roadway gas scanning detection method and equipment. Background Technology

[0002] During the tunneling, mining, ventilation adjustment, gas extraction, and equipment operation of coal mine roadways, gas outbursts, localized accumulation, and abnormally high concentrations may occur. Gas tends to accumulate in high areas of the roadway roof, sunken areas of the sidewalls, the face of the tunneling face, areas obstructed by equipment, and areas with insufficient airflow circulation. Failure to promptly monitor the gas concentration distribution within specific roadway spaces can easily compromise underground operational safety.

[0003] Current methods for monitoring methane gas in roadways mainly include fixed methane sensor monitoring and manual inspection with hand-held methane detectors. Fixed methane sensors can continuously monitor fixed locations, but their deployment is limited, and the detection results mainly reflect the methane concentration near the sensor, making it difficult to reflect spatial concentration differences at different heights, different sidewall locations, and near the working face within the roadway cross-section. Manual inspection can improve the flexibility of detection, but ordinary methane detectors are usually based on point detection, and inspectors can only obtain methane concentration values ​​at local sampling points, making it difficult to form continuous spatial distribution results of methane concentration in the roadway.

[0004] Under actual roadway conditions, methane concentration is not uniformly distributed. Influenced by ventilation airflow, roadway cross-sectional shape, equipment layout, roof undulations, localized collapses, and operational disturbances, high-concentration areas of methane may appear in specific sections of the roadway. Relying solely on single-point detection results to determine the overall methane status of the roadway can easily lead to overlooking abnormal local areas. This is especially true in the working face, return airway, high-lying roof areas, and poorly ventilated areas, where single-point detection is insufficient to accurately reflect the extent and spatial location of methane accumulation.

[0005] Therefore, there is a need for a method and equipment for scanning and detecting gas in roadways that can scan and detect the internal space of roadways, obtain the spatial distribution of gas concentration, and identify areas of abnormal gas accumulation, so as to improve the spatial coverage and anomaly identification capabilities of roadway gas detection. Summary of the Invention

[0006] The purpose of this invention is to provide a method and equipment for scanning and detecting methane in roadways, so as to solve the problems that existing point-based methane detection methods are difficult to reflect the spatial distribution of methane in roadways and difficult to identify abnormal methane accumulation in high-level areas of the roof and poorly ventilated areas in a timely manner.

[0007] To achieve the above objectives, the present invention provides a method for detecting gas in roadways, comprising the following steps:

[0008] S1. Set up at least two gas scanning detection devices in the roadway to be inspected, and record the installation position of each gas scanning detection device in the roadway spatial coordinate system. The roadway spatial coordinate system is with the roadway axis as the X-axis, the roadway width direction as the Y-axis, and the roadway height direction as the Z-axis.

[0009] S2 controls each gas scanning and detection device to scan the internal space of the roadway according to the preset scanning azimuth angle and preset scanning pitch angle. The gas detection module in each gas scanning and detection device obtains the gas concentration data on the corresponding scanning path along different scanning directions, and simultaneously obtains the scanning azimuth angle data, scanning pitch angle data and scanning distance data.

[0010] S3. Based on the installation location, scanning azimuth angle data, scanning elevation angle data, and scanning distance data of each gas scanning detection device, determine the scanning path of each gas scanning detection device in the roadway spatial coordinate system.

[0011] S4. Spatial matching of scanning paths from different gas scanning detection devices is performed to select the intersection area of ​​scanning paths that meets the preset intersection conditions, thereby obtaining effective gas detection points in the roadway.

[0012] S5. Construct a spatial grid model of the roadway based on the location data of the effective gas detection points in the roadway, and map the corresponding gas concentration data to the spatial grid model of the roadway to obtain a spatial distribution model of gas concentration in the roadway.

[0013] S6. Based on the spatial distribution model of gas concentration in the roadway, identify areas where the gas concentration in the roadway exceeds a preset concentration threshold, areas where the gas concentration gradient exceeds a preset gradient threshold, and areas where abnormal gas accumulation is formed by continuous over-limit grids.

[0014] S7. An alarm message is generated based on the spatial location, concentration value, and spatial range of the abnormal gas accumulation area, and the alarm message and the spatial distribution model of gas concentration in the roadway are sent to the mine safety monitoring platform.

[0015] Furthermore, the roadway to be inspected is one of the following: a tunneling roadway, a return air roadway, a transport roadway, a mining area roadway, a chamber connecting roadway, or a gas control drilling site connecting roadway.

[0016] Furthermore, in step S1, the gas scanning detection device is installed on the roadway floor, roadway sidewall, roadway fixed support or adjustable bracket, and the scanning areas of different gas scanning detection devices form overlapping scanning ranges in the roadway roof area, roadway sidewall area, tunneling face area or poorly ventilated area.

[0017] Further, in step S2, the scanning azimuth angle is the projection angle of the scanning direction onto the horizontal plane formed by the X-axis and Y-axis, and the scanning pitch angle is the angle between the scanning direction and the horizontal plane.

[0018] Further, in step S3, the scanning path is determined by the installation position, scanning azimuth angle, scanning pitch angle and scanning distance of the gas scanning detection equipment. The scanning distance is the distance from the gas scanning detection equipment to the roadway roof, roadway sidewall, roadway floor, tunneling face or preset detection section.

[0019] Furthermore, in step S4, the preset intersection conditions include that the minimum spatial distance between the scanning paths from different gas scanning detection devices is less than a preset distance threshold, and the time difference between the corresponding gas concentration data acquisitions is less than a preset time threshold.

[0020] Furthermore, after step S4, the method also includes outlier removal for effective gas detection points in the roadway. The outlier removal includes removing spatial points that exceed the roadway boundary, spatial points where the scanning paths do not form an effective intersection, spatial points where the acquisition time is not synchronized, and spatial points where the gas concentration changes abruptly.

[0021] Further, in step S5, the roadway spatial grid model is constructed based on the roadway cross-sectional dimensions, the roadway axial detection length, and the roadway boundary contour. The roadway spatial grid model includes a roof grid region, a left side grid region, a right side grid region, a floor adjacent grid region, and a tunneling face grid region.

[0022] Furthermore, in step S6, the abnormal gas accumulation area is determined based on the gas concentration difference between adjacent grid cells, the number of consecutive grid cells exceeding the limit, the spatial volume of consecutive grid cells exceeding the limit, and the duration of exceeding the limit.

[0023] The present invention also provides a roadway gas scanning and detection device, including a support, a rotating scanning mechanism, a gas detection module, a ranging module, an angle measuring module, a positioning module, a main control module, an alarm module, a display module, a communication module, and a power supply module.

[0024] The bracket is used to support the rotary scanning mechanism, the gas detection module, and the ranging module.

[0025] The rotating scanning mechanism is used to drive the gas detection module and the ranging module to rotate according to the preset scanning azimuth angle and preset scanning elevation angle.

[0026] The gas detection module is either a laser methane telemetry module or an open optical path methane detection module, used to acquire gas concentration data along different scanning directions on the corresponding scanning path.

[0027] The ranging module is used to acquire scanning distance data in different scanning directions.

[0028] The angle measurement module is used to acquire the scanning azimuth angle data and scanning elevation angle data of the gas detection module.

[0029] The positioning module is used to obtain the installation position of the roadway gas scanning and detection equipment in the roadway spatial coordinate system.

[0030] The main control module is connected to the rotary scanning mechanism, gas detection module, ranging module, angle measurement module, positioning module, alarm module, display module, communication module and power supply module respectively, and is used to generate a spatial distribution model of roadway gas concentration based on gas concentration data, scanning distance data, scanning azimuth angle data, scanning elevation angle data and installation position data.

[0031] The alarm module is used to output alarm information when the gas concentration exceeds a preset concentration threshold or when an abnormal gas accumulation area appears.

[0032] The display module is used to display the gas concentration value, scanning direction, equipment location, and abnormal gas accumulation area.

[0033] The communication module is used to send the detection results to the mine safety monitoring platform.

[0034] The power supply module is used to supply power to the rotary scanning mechanism, gas detection module, ranging module, angle measurement module, positioning module, main control module, alarm module, display module and communication module.

[0035] The beneficial effects of this invention are as follows:

[0036] First, the present invention uses at least two gas scanning detection devices to perform multi-directional scanning of the internal space of the roadway, which can expand from traditional single-point gas detection to spatial scanning detection, thereby improving the coverage of gas detection in the roadway.

[0037] Secondly, the present invention determines the scanning path by scanning azimuth angle, scanning elevation angle, scanning distance and equipment installation position, and obtains effective gas detection points in the roadway by spatial matching between different equipment scanning paths, which can improve the accuracy of spatial positioning of gas concentration.

[0038] Third, this invention maps effective gas detection points in the roadway to a roadway spatial grid model, which can form a spatial distribution model of gas concentration in the roadway, thereby intuitively reflecting the gas distribution status of the roof, sides, tunneling face and poorly ventilated areas.

[0039] Fourth, this invention identifies abnormal gas accumulation areas based on gas concentration threshold, concentration gradient threshold, continuous over-limit grid range, and over-limit duration, thereby improving the ability to identify local gas anomalies.

[0040] Fifth, this invention can send alarm information and a spatial distribution model of gas concentration in roadways to the mine safety monitoring platform, which facilitates underground gas detection, early warning and response, and safety management. Attached Figure Description

[0041] Figure 1 This is a schematic flowchart of a method for detecting gas in roadways according to the present invention.

[0042] Figure 2 This is a spatial schematic diagram of the multi-device scanning and detection system in the tunnel according to the present invention;

[0043] Figure 3 This is a schematic diagram of the structure of a roadway gas scanning and detection device according to the present invention.

[0044] Explanation of reference numerals in the attached diagram: 1. Support; 2. Rotary scanning mechanism; 3. Gas detection module; 4. Distance measuring module; 5. Angle measurement module; 6. Positioning module; 7. Main control module; 8. Alarm module; 9. Display module; 10. Communication module; 11. Power supply module; 12. Roadway to be inspected; 13. Roadway roof; 14. Left side of the roadway; 15. Right side of the roadway; 16. Roadway floor; 17. Tunneling face; 18. Scanning path; 19. Effective gas detection point in the roadway; 20. Abnormal gas accumulation area. Detailed Implementation

[0045] The technical solution of the present invention will be further described below with reference to the accompanying drawings. The described embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Where there is no conflict, the technical features in this embodiment can be combined with each other.

[0046] like Figures 1 to 3 As shown, this invention provides a method and equipment for scanning and detecting gas in roadways. This method is applicable to gas detection scenarios in underground coal mine roadways, particularly suitable for tunneling roadways, return air roadways, transport roadways, mining area roadways, chamber connecting roadways, and gas control drilling site connecting roadways. The area to be detected can be the roadway roof area, the left side of the roadway, the right side of the roadway, the area adjacent to the roadway floor, the tunneling face area, equipment obstruction areas, and areas with poor ventilation.

[0047] This embodiment uses gas scanning detection in a coal mine tunneling roadway as an example. The roadway to be detected, 12, is a rectangular cross-section tunneling roadway with an axial detection length of 60m, a width of 5m, and a height of 3.5m. A spatial coordinate system is established for the roadway, with the roadway axial direction as the X-axis, the roadway width direction as the Y-axis, and the roadway height direction as the Z-axis. The positive X-axis direction points from the roadway entrance to the working face 17, the positive Y-axis direction points from the left side 14 to the right side 15, and the positive Z-axis direction points from the roadway floor 16 to the roadway roof 13. The effective detection range for the roadway 12 is 0≤x≤60m, -2.5m≤y≤2.5m, and 0≤z≤3.5m.

[0048] Two gas scanning detection devices, designated as Gas Scanning Detection Device A and Gas Scanning Detection Device B, are installed in the roadway 12 to be inspected. Gas Scanning Detection Device A is located near the left side 14 of the roadway, and Gas Scanning Detection Device B is located near the right side 15 of the roadway. The installation position of Gas Scanning Detection Device A is designated as PA, with coordinates (10, -2.2, 1.2), and the installation position of Gas Scanning Detection Device B is designated as PB, with coordinates (10, 2.2, 1.2), in meters. Both devices are mounted on the roadway floor 16 via bracket 1. The initial installation height of both the gas detection module 3 and the distance measuring module 4 is 1.2 meters.

[0049] To ensure effective scanning overlap between the two devices within the tunnel space, the initial scanning direction of the first gas scanning detection device A is directed towards the right side 15 of the tunnel, the tunnel roof 13, and the working face 17, while the initial scanning direction of the second gas scanning detection device B is directed towards the left side 14 of the tunnel, the tunnel roof 13, and the working face 17. The scanning areas of the two devices overlap in the tunnel roof 13, the working face 17, and the upper and middle space of the tunnel.

[0050] Before the formal scanning, the two gas scanning and detection devices underwent initial calibration. Initial calibration included calibration of the device installation position, zero-position calibration of the rotary scanning mechanism 2, distance calibration of the ranging module 4, and zero-point calibration of the gas detection module 3. The device installation position calibration was used to determine the coordinates of PA and PB in the roadway spatial coordinate system; the zero-position calibration of the rotary scanning mechanism 2 was used to determine the starting position for calculating the scanning azimuth and elevation angles; the distance calibration of the ranging module 4 was used to ensure that the scanning distance data was consistent with the actual roadway boundary; and the zero-point calibration of the gas detection module 3 was used to reduce the impact of initial drift of the gas sensor on the detection results.

[0051] Two gas scanning detection devices performed synchronous scanning according to preset scanning parameters. The scanning azimuth range of the first gas scanning detection device A was set to 20° to 160°, and the scanning azimuth range of the second gas scanning detection device B was set to 200° to 340°. The scanning elevation angle range of both devices was set to -10° to 70°; the scanning azimuth step size was set to 5°, and the scanning elevation step size was set to 5°; the effective ranging range of the ranging module 4 was set to 0.5m to 30m; and the gas concentration sampling interval was set to 1s.

[0052] During the scanning process, the main control module 7 controls the rotating scanning mechanism 2 to adjust the scanning azimuth and scanning elevation angles sequentially. After reaching each preset scanning direction, the gas detection module 3 acquires the gas concentration data along the corresponding scanning path, the ranging module 4 acquires the scanning distance data along the scanning direction, the angle measurement module 5 acquires the scanning azimuth and scanning elevation angle data along the scanning direction, and the positioning module 6 provides the installation position data of the corresponding equipment.

[0053] The main control module 7 binds the device number, device installation location, scanning azimuth angle, scanning elevation angle, scanning distance, gas concentration value, and acquisition time under the same scanning direction to form a scanning detection data. The scanning detection data is stored in tabular form, with fields including device number (Device_ID), device coordinates (X0, Y0, Z0), scanning azimuth angle (Alpha), scanning elevation angle (Beta), scanning distance (Distance), gas concentration (CH4), and acquisition time (Time).

[0054] To ensure the validity of the scanning detection data, the main control module 7 preprocesses the data. Preprocessing includes invalid distance rejection, invalid concentration rejection, angle range rejection, and time synchronization rejection. If the scanning distance is less than 0.5m or greater than 30m, the corresponding scanning detection data is rejected; if the gas concentration value is less than 0 or exceeds the range of the gas detection module 3, the corresponding scanning detection data is rejected; if the scanning azimuth or elevation angle exceeds the preset scanning range, the corresponding scanning detection data is rejected; if the difference between the gas concentration acquisition time and the distance acquisition time in the same scanning direction is greater than 1s, the corresponding scanning detection data is rejected.

[0055] For any preprocessed scan detection data, let the installation location of the i-th gas scanning detection device be Pi(x). i y i , z i The scanning azimuth angle corresponding to the j-th scanning path 18 is α. ij The scanning elevation angle is β ij The scanning distance is L ij The gas concentration value is C ij The main control module 7, based on Pi and α,ij β ij and L ij Calculate the scan endpoint Q of scan path 18. ij Scan endpoint Q ij The coordinates are:

[0056] x ij =x i +L ij cosβ ij cosα ij ;

[0057] y ij =y i +L ij cosβ ij sinα ij ;

[0058] z ij =z i +L ij sinβ ij；

[0059] In the formula, x ij y ij and z ij The endpoint Q is respectively ij The X-axis, Y-axis, and Z-axis coordinates in the tunnel spatial coordinate system; α ij For the scanning azimuth angle; β ij For scanning pitch angle; L ij This represents the scanning distance.

[0060] Through the above calculations, the main control module 7 obtains the starting point, direction, and ending point of each scanning path 18 in the roadway spatial coordinate system. Each scanning path 18 is associated with the corresponding gas concentration value C. ij Related.

[0061] To obtain the effective gas detection point 19 in the roadway, the main control module 7 performs spatial matching on the scanning path 18 formed by the first gas scanning detection device A and the second gas scanning detection device B. For any scanning path 18 of the first gas scanning detection device A and any scanning path 18 of the second gas scanning detection device B, the main control module 7 calculates the minimum spatial distance d between the two scanning paths 18. min And calculate the acquisition time difference Δt of the gas concentration data corresponding to the two scanning paths 18.

[0062] When d min When the distance is ≤0.5m and Δt≤2s, the two scanning paths 18 are determined to meet the preset intersection condition. When the two scanning paths 18 actually intersect, the intersection point is taken as the candidate intersection position; when the two scanning paths 18 do not actually intersect but meet the condition d minWhen the distance is ≤0.5m, the midpoint of the line connecting the nearest points of the two scanning paths 18 is taken as the candidate intersection point. The candidate intersection point is denoted as R. k Its coordinates are (x k y k , z k ), where k is the candidate intersection position number.

[0063] For candidate intersection position R k Determine the roadway boundary. If R k Satisfying 0≤x k ≤60m, -2.5m≤y k ≤2.5m, 0≤z k If the distance is ≤3.5m, then determine R. k Located within the effective detection area of ​​the roadway; if R k If the above conditions are not met, then R is determined to be false. k If the candidate intersection is located outside the effective detection area of ​​the roadway, it will be eliminated.

[0064] For candidate intersection locations identified by the roadway boundary, a further concentration consistency assessment is performed. Let the gas concentration value along the scanning path of the first gas scanning detection device A be CA, and the gas concentration value along the scanning path of the second gas scanning detection device B be CB. When |CA-CB|≤0.10%, the average of CA and CB is taken as the gas concentration value at that spatial location. When |CA-CB|>0.10%, that spatial location is marked as a detection point to be verified, and the larger of CA and CB is taken as the gas concentration value for safety warning.

[0065] After the above screening, boundary judgment, and concentration consistency judgment, the system obtains 326 effective gas detection points 19 in the roadway from a set of example scan data in this embodiment. Each effective gas detection point 19 in the roadway includes spatial coordinates, gas concentration value, equipment number involved in matching, scanning azimuth angle, scanning elevation angle, scanning distance, and acquisition time.

[0066] After obtaining 19 effective gas detection points in the roadway, the system performs spatial mesh modeling of the roadway. Based on the geometric dimensions of the roadway 12 to be detected, the detection area is defined as 0≤x≤60m, -2.5m≤y≤2.5m, and 0≤z≤3.5m. The mesh resolution is set to 0.5m×0.5m×0.5m. Thus, the roadway space is divided into 120 mesh segments along the X-axis, 10 mesh segments along the Y-axis, and 7 mesh segments along the Z-axis, generating a total of 8400 mesh elements.

[0067] The 8400 grid cells are divided into roof grid area, left side grid area, right side grid area, floor adjacent grid area, and tunneling face grid area according to their location. Among them, grid cells with z ≥ 3.0m are assigned to the roof grid area; grid cells with y ≤ -2.0m are assigned to the left side grid area; grid cells with y ≥ 2.0m are assigned to the right side grid area; grid cells with z ≤ 0.5m are assigned to the floor adjacent grid area; and grid cells with x ≥ 55m are assigned to the tunneling face grid area.

[0068] The system maps 326 effective gas detection points 19 in the roadway spatial grid model. For each effective gas detection point 19, the system determines its grid cell based on its spatial coordinates and assigns its gas concentration value to that grid cell. When multiple effective gas detection points 19 exist within a grid cell, the system calculates the average of the multiple gas concentration values ​​as the initial gas concentration value for that grid cell. When any of the multiple gas concentration values ​​exceeds a preset concentration threshold, the system simultaneously records the maximum gas concentration value for that grid cell.

[0069] For grid cells not assigned values ​​by any effective gas detection points 19 in the roadway, the system uses a nearest neighbor interpolation method to complete the gas concentration calculation. Specifically, several nearest assigned grid cells are selected and weighted according to spatial distance from nearest to farthest. Assigned grid cells that are closer have a higher weight, while those that are farther away have a lower weight. After nearest neighbor interpolation, each grid cell in the roadway space obtains a corresponding gas concentration estimate.

[0070] To facilitate the identification of gas distribution areas with different risk levels, the system classifies gas concentration into four levels:

[0071] The primary region is a low-concentration region where C < 0.50%;

[0072] The secondary region is the region of interest where 0.50% ≤ C < 1.00%;

[0073] Level 3 areas are warning areas where 1.00% ≤ C < 1.50%;

[0074] Level 4 areas are high-risk areas with a risk level of C ≥ 1.50%.

[0075] The above concentration levels can be adjusted according to coal mine safety monitoring requirements or on-site preset alarm thresholds.

[0076] The system assigns and marks grid cells according to the gas concentration level from low to high.

[0077] For the first-level region, the corresponding grid cells are marked as low-concentration grids;

[0078] For secondary regions, the corresponding grid cells are marked as grids of interest;

[0079] For Level 3 areas, the corresponding grid cells will be marked as warning grids;

[0080] For Level 4 regions, the corresponding grid cells are marked as high-risk grids.

[0081] If the same grid cell is assigned different risk levels in different scan data, the higher risk level is taken as the final risk level of that grid cell.

[0082] Based on a set of example scan data constructed in this embodiment, the spatial distribution of gas concentration in the roadway reconstructed by the system is as follows: the maximum gas concentration is 1.72%, the average gas concentration is 0.43%, and the level 3 and level 4 regions are mainly distributed in the roof grid area near working face 17 and the local depression area on the right side. The number of continuous out-of-limit grid cells is 28, corresponding to a spatial volume of 3.5 m³.

[0083] The system further identifies the abnormal gas accumulation area 20.

[0084] First, the system marks grid cells with C ≥ 1.00% as out-of-limit grid cells;

[0085] Then, the gas concentration difference between adjacent grid cells is calculated. When the gas concentration difference between adjacent grid cells is greater than 0.30%, the corresponding area is marked as a concentration gradient anomaly area;

[0086] Finally, the system determines whether the out-of-limit grid cells are continuously distributed. When the number of continuously out-of-limit grid cells is not less than 8 and the corresponding spatial volume is not less than 1.0 m³, the continuously out-of-limit area is identified as an abnormal gas accumulation area 20.

[0087] Based on the above judgment criteria, the system identified two abnormal gas accumulation areas 20 in a set of example scan data in this embodiment. The first abnormal gas accumulation area 20 is located within the range of x=55m to 60m, y=0.8m to 2.2m, and z=2.5m to 3.5m, belonging to the high-level accumulation area of ​​the roof near the tunneling face 17. The second abnormal gas accumulation area 20 is located within the range of x=38m to 44m, y=1.8m to 2.5m, and z=1.5m to 2.8m, belonging to the local accumulation area near the right sidewall 15 of the roadway.

[0088] The system generates alarm information based on the spatial location, maximum gas concentration, average gas concentration, number of consecutive grid cells exceeding limits, and spatial volume of the abnormal gas accumulation area 20. The alarm information includes the abnormal area number, abnormal area type, spatial coordinate range, maximum gas concentration, average gas concentration, number of grid cells exceeding limits, and alarm level.

[0089] Based on a set of example scan data constructed in this embodiment, the maximum gas concentration in the first abnormal gas accumulation area 20 is 1.72%, the average gas concentration is 1.26%, the number of consecutively exceeding the limit grid cells is 18, and the spatial volume is 2.25 m³, which the system determines as a high-risk alarm. The maximum gas concentration in the second abnormal gas accumulation area 20 is 1.31%, the average gas concentration is 1.08%, the number of consecutively exceeding the limit grid cells is 10, and the spatial volume is 1.25 m³, which the system determines as a warning alarm.

[0090] Alarm module 8 outputs audible and visual alarms according to the alarm level.

[0091] For early warning alarms, alarm module 8 outputs intermittent audible and visual alerts;

[0092] For high-risk alarms, alarm module 8 outputs continuous audible and visual alerts.

[0093] Display module 9 synchronously displays the spatial distribution model of gas concentration in the roadway, and marks the location and range of the abnormal gas accumulation area 20 in the model.

[0094] The communication module 10 sends the detection results from this embodiment to the mine safety monitoring platform. The uploaded content includes the original scan detection data, effective gas detection points 19 in the roadway, the roadway spatial grid model, the spatial distribution model of gas concentration in the roadway, the abnormal gas accumulation area 20, and alarm information. After receiving the data, the mine safety monitoring platform can use it for ventilation control, gas management, abnormal area review, personnel evacuation alerts, and safety inspection records.

[0095] As can be seen from the above embodiments, the present invention can scan and detect gas concentration in roadway space, and form the spatial distribution result of roadway gas concentration through scanning path matching, effective detection point screening, gridded concentration assignment, and abnormal accumulation area identification. Compared with point gas detection, the present invention can further reflect the spatial distribution status of gas in high-level areas of the roadway roof, local areas of the sidewalls, and near the working face.

[0096] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of protection claimed by the present invention.

Claims

1. A method for detecting gas in roadways, characterized in that, Includes the following steps: S1, set up at least two gas scanning detection devices in the roadway to be inspected, and record the installation position of each gas scanning detection device in the roadway spatial coordinate system, wherein the roadway spatial coordinate system is with the roadway axis as the X-axis, the roadway width direction as the Y-axis, and the roadway height direction as the Z-axis; S2 controls each gas scanning and detection device to scan the internal space of the roadway according to the preset scanning azimuth angle and preset scanning pitch angle. The gas detection module in each gas scanning and detection device obtains the gas concentration data on the corresponding scanning path along different scanning directions, and simultaneously obtains the scanning azimuth angle data, scanning pitch angle data and scanning distance data. S3. Based on the installation location, scanning azimuth angle data, scanning elevation angle data and scanning distance data of each gas scanning detection device, determine the scanning path of each gas scanning detection device in the roadway spatial coordinate system; S4. Spatial matching of scanning paths from different gas scanning detection devices is performed to select the intersection area of ​​scanning paths that meets the preset intersection conditions, thereby obtaining effective gas detection points in the roadway. S5. Construct a roadway spatial grid model based on the location data of effective gas detection points in the roadway, and map the corresponding gas concentration data to the roadway spatial grid model to obtain a roadway gas concentration spatial distribution model. S6. Based on the spatial distribution model of gas concentration in the roadway, identify areas where the gas concentration in the roadway exceeds a preset concentration threshold, areas where the gas concentration gradient exceeds a preset gradient threshold, and areas where abnormal gas accumulation is formed by continuous over-limit grids. S7. An alarm message is generated based on the spatial location, concentration value, and spatial range of the abnormal gas accumulation area, and the alarm message and the spatial distribution model of gas concentration in the roadway are sent to the mine safety monitoring platform.

2. The method for detecting gas in roadways according to claim 1, characterized in that, The roadway to be tested is one of the following: tunneling roadway, return air roadway, transport roadway, mining area roadway, chamber connecting roadway, or gas control drilling site connecting roadway.

3. The method for detecting gas in roadways according to claim 1, characterized in that, In step S1, the gas scanning detection equipment is installed on the roadway floor, roadway sidewall, roadway fixed support or adjustable bracket. The scanning areas of different gas scanning detection equipment form overlapping scanning ranges in the roadway roof area, roadway sidewall area, tunneling face area or poorly ventilated area.

4. The method for detecting gas in roadways according to claim 1, characterized in that, In step S2, the scanning azimuth angle is the projection angle of the scanning direction onto the horizontal plane formed by the X-axis and Y-axis, and the scanning pitch angle is the angle between the scanning direction and the horizontal plane.

5. The method for detecting gas in roadways according to claim 1, characterized in that, In step S3, the scanning path is determined by the installation position, scanning azimuth angle, scanning elevation angle and scanning distance of the gas scanning detection equipment. The scanning distance is the distance from the gas scanning detection equipment to the roadway roof, roadway sidewall, roadway floor, tunneling face or preset detection section.

6. The method for detecting gas in roadways according to claim 1, characterized in that, In step S4, the preset intersection conditions include that the minimum spatial distance between the scanning paths from different gas scanning detection devices is less than a preset distance threshold, and the time difference between the acquisition of the corresponding gas concentration data is less than a preset time threshold.

7. The method for detecting gas in roadways according to claim 1, characterized in that, After step S4, the method further includes outlier removal for effective gas detection points in the roadway. Outlier removal includes removing spatial points that exceed the roadway boundary, spatial points where the scanning paths do not form an effective intersection, spatial points where the acquisition time is not synchronized, and spatial points where the gas concentration changes abruptly.

8. The method for detecting gas in roadways according to claim 1, characterized in that, In step S5, the tunnel spatial grid model is constructed based on the tunnel cross-sectional dimensions, the tunnel axial detection length, and the tunnel boundary contour. The tunnel spatial grid model includes a roof grid area, a left side grid area, a right side grid area, a floor adjacent grid area, and a tunneling face grid area.

9. The method for detecting gas in roadways according to claim 1, characterized in that, In step S6, the abnormal gas accumulation area is determined based on the gas concentration difference between adjacent grid cells, the number of consecutive grid cells exceeding the limit, the spatial volume of consecutive grid cells exceeding the limit, and the duration of exceeding the limit.

10. A tunnel gas scanning and detection device, characterized in that, The system includes a support frame, a rotary scanning mechanism, a gas detection module, a ranging module, an angle measurement module, a positioning module, a main control module, an alarm module, a display module, a communication module, and a power supply module. The support frame supports the rotary scanning mechanism, the gas detection module, and the ranging module. The rotary scanning mechanism drives the gas detection module and the ranging module to rotate according to preset scanning azimuth and elevation angles. The gas detection module is either a laser methane telemetry module or an open-path methane detection module, used to acquire gas concentration data along different scanning directions. The ranging module acquires scanning distance data in different scanning directions. The angle measurement module acquires the scanning azimuth and elevation angle data of the gas detection module. The positioning module determines the installation position of the roadway gas scanning detection equipment in the roadway spatial coordinate system. The main control module is connected to the rotary scanning mechanism, gas detection module, ranging module, angle measurement module, positioning module, alarm module, display module, communication module, and power supply module, respectively. It is used to generate a spatial distribution model of roadway gas concentration based on gas concentration data, scanning distance data, scanning azimuth angle data, scanning elevation angle data, and installation location data. The alarm module outputs alarm information when the gas concentration exceeds a preset concentration threshold or when an abnormal gas accumulation area appears. The display module displays the gas concentration value, scanning direction, equipment location, and abnormal gas accumulation area. The communication module sends the detection results to the mine safety monitoring platform. The power supply module provides power to the rotary scanning mechanism, gas detection module, ranging module, angle measurement module, positioning module, main control module, alarm module, display module, and communication module.

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