Combined detection system and method for detecting methane gas leakage and storage medium

Abstract

The invention discloses a combined detection system and method for detecting methane gas leakage and a storage medium. The combined detection system comprises an anti-explosion holder, a laser gas detector, an infrared thermal imager, a high-definition camera and a control unit, wherein the laser gas detector, the infrared thermal imager, the high-definition camera and the control unit are arranged on the anti-explosion holder; when the infrared thermal imager detects that the temperature data of an area is smaller than the historical temperature data, the laser gas detector detects the concentration data of suspected methane gas in the area, and when the control unit judges that the concentration data is larger than a set concentration value, the high-definition camera captures a current picture, and the control unit defines a reference plane coordinate system according to the current picture; the control unit controls the explosion-proof holder to drive the detection device to perform detection in four directions based on the reference plane coordinate system and record the maximum value of real-time concentration data, the minimum value of real-time temperature data and the center coordinates of the corresponding shooting area; the leakage point of the methane gas can be timely and accurately determined according to the center coordinate of the shooting area and the set deviation distance, and the accident traceability is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of methane gas leakage detection, and in particular to a composite detection system, method and storage medium for detecting methane gas leakage. Background Art

[0002] In the process of natural gas production, various flammable, explosive, toxic and harmful gases are inevitably produced, such as methane, the main component of natural gas. Once the above gases leak and accumulate in the surrounding environment to a certain concentration, they will easily cause combustion, explosion, poisoning and other malignant accidents. At present, in order to prevent and detect natural gas leakage, reliable gas detection and alarm equipment is mainly used to detect, monitor and promptly alarm the leaked gas in the natural gas production process. This prevention and monitoring method plays an extremely important role in avoiding personal injury and fire and explosion accidents.

[0003] The gas detection alarm equipment currently used is usually a single point gas detector, laser beam gas detector, laser pan-tilt gas detector or infrared thermal imaging gas detector in the process equipment area, which detects gas leakage with a single detection method. However, this single detection method can only detect and analyze the leaked gas qualitatively or quantitatively, and cannot meet the requirements of gas leakage detection accuracy and real-time performance. In addition, there are also some composite gas leakage detection systems that integrate laser gas detectors, infrared thermal imagers, high-definition cameras and other detection devices on mobile pan-tilts to conduct joint patrol detection of process equipment areas. However, this composite gas leakage detection system is actually only driven by the mobile pan-tilt to move the detection devices. Each detection device still operates independently and lacks a linkage mechanism. The detection data of each detection device cannot be combined and applied to accurately locate the leakage situation. The detection technology lacks complementarity and integration, which makes the accuracy and real-time performance of the composite gas leakage detection system still need to be improved.

[0004] Therefore, how to provide a gas leak detection system that can combine and apply multiple gas leak detection technologies to improve the accuracy and real-time performance of gas leak detection has become one of the important technical problems that need to be solved urgently in this field. Summary of the invention

[0005] The technical problem to be solved by this technical solution is how to enable multiple gas leakage detection devices to detect in a unified and linked manner and combine the detection data for application, so as to locate the methane gas leakage point in a timely and accurate manner.

[0006] In order to solve the above technical problems, the present technical scheme provides a composite detection system for detecting methane gas leakage, which includes: a laser gas detector, an infrared thermal imager, a high-definition camera, an explosion-proof pan-tilt and a control unit; wherein the laser gas detector, the infrared thermal imager and the high-definition camera are all installed on the explosion-proof pan-tilt and driven by the explosion-proof pan-tilt to perform a uniform circumferential rotation and the same angle of upward or downward tilt, and the laser detection path of the laser gas detector and the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are within the same central area; the control unit is installed on the explosion-proof pan-tilt and is electrically connected to the laser gas detector, the infrared thermal imager, the high-definition camera and the explosion-proof pan-tilt respectively; the explosion-proof pan-tilt performs a cruise mode under normal conditions, and when the infrared thermal imager detects that the temperature data of an area is less than a historical temperature data of the area, the laser gas detector detects the concentration data of the suspected methane gas in the area and transmits it to the control unit, the control unit compares the concentration data with a set concentration value, and when the concentration data is less than or equal to the set concentration value, the control unit controls the explosion-proof pan-tilt to continue to perform the cruise mode;When the concentration data is greater than the set concentration value, the control unit controls the explosion-proof pan / tilt to suspend operation and controls the infrared thermal imager to start the global minimum temperature detection within the thermal imaging area. Then, the control unit controls the explosion-proof pan / tilt to rotate so that the center of the thermal imaging area of ​​the infrared thermal imager is located in the global minimum temperature area within the thermal imaging area and executes the scanning mode. The scanning mode is that the high-definition camera captures the picture of the current shooting area and transmits it to the control unit. The control unit uses the geometric center of the picture as the origin coordinate to define a reference plane coordinate system and maps it with the current shooting area. The control unit controls the explosion-proof pan / tilt to synchronously drive the laser gas detector, the infrared thermal imager and the high-definition camera to rotate up, down, left and right by a set angle based on the current position, and the explosion-proof pan / tilt returns to the current position after each rotation action is implemented. In the rotation process, the center of the shooting area of ​​the high-definition camera always moves along the coordinate axis of the reference plane coordinate system, and the center of the shooting area returns to the origin coordinate of the reference plane coordinate system after each movement. The laser gas detector and the infrared thermal imager will rotate during the process. The real-time concentration data of suspected methane gas detected and the real-time temperature data of the center of the thermal imaging area are transmitted to the control unit, and the control unit records the center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data. The control unit then determines that when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is less than or equal to a set deviation distance, the origin coordinate is determined as the methane gas leakage point. Otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is greater than the set deviation distance, the control unit calculates a midpoint coordinate based on the reference plane coordinate system according to the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value, and controls the explosion-proof pan / tilt to rotate so that the center of the shooting area of ​​the high-definition camera coincides with the midpoint coordinate, and then re-implements the above scanning mode until the methane gas leakage point is determined. ;

[0007] Accordingly, the composite detection system of the present technical solution integrates the laser gas detector, infrared thermal imager, high-definition camera and explosion-proof pan-tilt head, so as to uniformly perform rotation, upward and downward operation detection under the operation of the explosion-proof pan-tilt head, and each detection device is not for independent detection operation, but a linkage mechanism is added between the detection devices, so that the detection data of each detection device can be complementary and verified, so as to improve the detection accuracy of the composite detection system. The laser detection path of the laser gas detector and the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are in the same central area, which can ensure that the effective detection range of the above detection device has a high consistency. The present technical solution also makes comprehensive application of the detection data of the above detection devices, so that qualitative analysis and quantitative analysis complement each other, and through the integration of technology to conduct comprehensive analysis of multiple detection data, the composite detection system can timely and accurately determine the leakage point of methane gas, thereby providing decision makers with more valuable judgment basis in terms of prevention and accident tracing.

[0008] As another implementation of the technical solution, the laser detection path of the laser gas detector, the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are on the same plane and close to each other within the same central area. In this way, the consistency of the effective detection range of the above detection device can be further improved.

[0009] As another implementation of the technical solution, the center coordinates of the shooting area when the real-time concentration data is the highest value are (X1, Y1), the center coordinates of the shooting area when the real-time temperature data is the lowest value are (X2, Y2), and the distance S between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is = Midpoint coordinates

[0010] As another implementation of the technical solution, the composite detection system also includes: a remote terminal, the remote terminal has a storage unit and stores environmental feature data, the control unit is electrically connected to the remote terminal through a wired or wireless data communication method, the high-definition camera is a network high-definition zoom camera, the network high-definition zoom camera can perform zoom shooting according to the control instructions of the remote terminal transmitted via the control unit and transmit the captured image to the remote terminal through the control unit for storage, and the remote terminal can perform feature recognition on the captured image according to the environmental feature data to determine the location information of the captured image. In this way, by storing the captured image, not only can the ability to trace the accident be ensured, but also the intelligence level of the composite detection system can be improved through feature recognition technology.

[0011] As another implementation of the technical solution, the composite detection system further includes: an alarm device, which is installed on the explosion-proof pan / tilt and electrically connected to the control unit, and controls the alarm device to sound an alarm when the control unit determines the methane gas leakage point. In this way, the timeliness of handling the methane gas leakage point can be improved.

[0012] In order to solve the above technical problems, the present technical solution also provides a detection method for detecting methane gas leakage, the steps of which include:

[0013] Historical temperature data collection: The explosion-proof PTZ drives the infrared thermal imager to collect historical temperature data of the entire area of ​​the surrounding environment;

[0014] Cruise detection: The laser gas detector, infrared thermal imager and high-definition camera are driven by the explosion-proof pan / tilt to detect the surrounding environment in cruise mode, and the laser detection path of the laser gas detector is within the same central area as the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located;

[0015] Abnormal situation filtering: When the infrared thermal imager detects that the temperature data of an area is lower than the historical temperature data of the area, the laser gas detector detects the concentration data of the suspected methane gas in the area. When the concentration data is less than or equal to a set concentration value, the above cruise detection steps are continued;

[0016] Abnormal situation scanning: when the concentration data is greater than the set concentration value, the explosion-proof pan / tilt stops running, the infrared thermal imager starts the global minimum temperature detection within the thermal imaging area, and the explosion-proof pan / tilt rotates to move the center of the thermal imaging area of ​​the infrared thermal imager to the global minimum temperature area to perform abnormal scanning. The abnormal scanning is that the high-definition camera captures the picture of the current shooting area, and defines a reference plane coordinate system with the geometric center of the picture as the origin coordinate and maps it with the current shooting area. Then, the explosion-proof pan / tilt drives the laser gas detector, the infrared thermal imager and the high-definition camera to rotate up, down, left and right by a set angle based on the current position, and the explosion-proof pan / tilt returns to the current position after each rotation action is implemented. During the rotation process, the center of the shooting area of ​​the high-definition camera always moves along the coordinate axis of the reference plane coordinate system, and after each movement, the center of the shooting area returns to the origin coordinate of the reference plane coordinate system. The laser gas detector and the infrared thermal imager collect the real-time concentration data of the suspected methane gas detected during the rotation process and the real-time temperature data of the center of the thermal imaging area, and determine the center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data.

[0017] Determine the methane gas leakage point: when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is less than or equal to a set deviation distance, the origin coordinates are determined as the methane gas leakage point; otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is greater than the set deviation distance, a midpoint coordinate based on the reference plane coordinate system is calculated based on the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value, the explosion-proof pan / tilt rotates to make the center of the shooting area of ​​the high-definition camera coincide with the midpoint coordinate, and then the above-mentioned abnormal scan is performed until the methane gas leakage point is determined.

[0018] Through the above detection method, the analysis of the historical temperature data of the surrounding environment of the process unit area can timely discover the area suspected of methane gas leakage, and through the abnormal situation filtering step, the interference with the detection result can be timely eliminated, thereby effectively improving the accuracy of the detection result. This detection method makes the detection data of each detection device complementary and verified by unifying the operation detection and linkage of each detection device, and makes the qualitative analysis and quantitative analysis complement each other by comprehensively applying each detection data, so that the detection result is more accurate and reliable, so as to be able to timely and accurately determine the leakage point of methane gas, and provide decision makers with more valuable judgment basis in both prevention and accident tracing.

[0019] As another implementation of the technical solution, the center coordinates of the shooting area when the real-time concentration data is the highest value are (X1, Y1), the center coordinates of the shooting area when the real-time temperature data is the lowest value are (X2, Y2), and the distance S between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is = Midpoint coordinates

[0020] As another implementation of the technical solution, after the patrol detection step, an image saving and location identification step is also included: the image captured by the high-definition camera is transmitted to the remote terminal for storage, and the remote terminal can identify the image according to the environmental feature data to determine the image's location information. In this way, not only can the ability to trace the accident be ensured, but also the intelligence level of location information identification can be improved, which is conducive to the timely disposal of the gas leakage area.

[0021] As another implementation of the technical solution, after the step of determining the methane gas leakage point, a leakage alarm step is also included: after the methane gas leakage point is determined, a leakage alarm is performed, thereby improving the timeliness of handling the methane gas leakage point.

[0022] In order to solve the above technical problem, the present technical solution also provides a computer storage medium, which stores a program that can execute the above detection method. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the functional module structure of the composite detection system of the present invention.

[0024] Figure 2 It is a functional logic flow diagram of the composite detection system of the present invention.

[0025] Figure 3 Schematic diagram of a composite detection system with a remote terminal.

[0026] Explanation of symbols in the accompanying drawings:

[0027] 1 composite detection system; 10 laser gas detector; 11 laser detection path; 20 infrared thermal imager; 21 straight line where the center of the thermal imaging area is located; 30 high-definition camera; 31 straight line where the center of the shooting area is located; 40 control unit; 50 explosion-proof pan / tilt head; 60 range of the same central area; 70 remote terminal; 71 storage unit. DETAILED DESCRIPTION

[0028] The detailed description and technical contents of the present invention are described as follows with reference to the accompanying drawings. However, the accompanying drawings are only provided for reference and description and are not intended to limit the present invention.

[0029] In order to solve the problems that the traditional gas detection alarm equipment and the detection devices of the composite gas leakage detection system lack linkage mechanism, single detection means, high false alarm and missed alarm rate of the equipment or system, poor safety, timeliness and reliability, the present invention provides a composite detection system, method and storage medium for detecting methane gas leakage. Specifically:

[0030] The composite detection system for detecting methane gas leakage provided by the present invention (hereinafter referred to as the composite detection system) includes a laser gas detector, an infrared thermal imager, a high-definition camera, an explosion-proof pan-tilt and a control unit. Among them, the laser gas detector, the infrared thermal imager, the high-definition camera and the control unit are integrated and installed on the explosion-proof pan-tilt (sled) and can be driven by the explosion-proof pan-tilt to perform a uniform circumferential rotation and the same angle of upward or downward tilt. The above-mentioned detection device is integrated into the sled-type structure on the explosion-proof pan-tilt and has been widely used in existing composite gas leakage detection systems. It belongs to the prior art. Therefore, the sled-type structure will not be described in detail in the present invention. In addition, the principle and device structure of using a laser gas detector to detect the concentration of methane gas, and the principle and device structure of using an infrared thermal imager to detect gas leakage caused by the throttling effect of high-pressure gas leaking through plugs, small holes, etc. at the locations of pipelines, interfaces, valves, etc. in the process device area are also prior art. Therefore, they will not be described in detail in the present invention.

[0031] like Figure 1 As shown, in the composite detection system 1 of the present invention, the laser detection path 11 of the laser gas detector 10 and the straight line 21 where the center of the thermal imaging area of ​​the infrared thermal imager 20 and the straight line 31 where the center of the shooting area of ​​the high-definition camera 30 are located are in the same central area range 60. Since the axis of the detection area of ​​the above-mentioned detection device (the straight line where the center of the detection area is located) cannot be colinear, therefore, when detecting a certain part of the detection object, the center of the detection of the above-mentioned detection device cannot be concentrated at one point, and by making the installation structure of the above-mentioned detection device as compact as possible, the angle between the axes of the detection area of ​​each detection device can be reduced, so that the axes of the detection area of ​​each detection device are close to each other within the same central area range. In other words, it should be ensured that the distance between most of the detected objects in the process device area and the composite detection system should be within the same central area range, so as to ensure the consistency of the effective detection range of the above-mentioned detection device, thereby improving the accuracy of locating the gas leakage point, and therefore it is very important for the selection and setting of the composite detection system in the process device area. The control unit 40 is electrically connected to the laser gas detector 10, the infrared thermal imager 20, the high-definition camera 30 and the explosion-proof pan / tilt 50 respectively. The explosion-proof PTZ 50 normally executes the cruise mode, which can be a preset cruise mode. This mode can set up to 9 cruise routes, and each cruise route can be set up with 16 prefabricated points. This mode can flexibly set the cruise route according to the characteristics of the pipeline laying in the process equipment area and the actual detection needs, so as to achieve key detection of key target positions; in addition, the cruise mode can also be an apple peel scanning cruise mode, in which the explosion-proof PTZ can rotate 360 ​​degrees from top to bottom (the rotation angle can be configured by itself, such as scanning only within 180 degrees), to maximize the guarantee of scanning the entire process equipment area without blind spots. Combined with Figure 2As shown, when the infrared thermal imager detects that the temperature data of an area does not match the historical temperature data of the area (the basic temperature data under normal conditions collected in advance by the infrared thermal imager), if the temperature data of the area is greater than the historical temperature data of the area, it indicates that there is a possibility of combustion. At this time, the composite detection system will immediately alarm. Of course, in order to avoid system misjudgment caused by environmental, climatic and other factors, the comparison and judgment of the temperature data and the historical temperature data are usually carried out within a set temperature error range. This is a common practice in the prior art; and if the temperature data of the area is less than the historical temperature data of the area, it indicates that there is a possibility of gas leakage. At this time, the laser gas detector will detect the area. The concentration data of suspected methane gas is transmitted to the control unit, which compares the concentration data with a set concentration value (for example, 1000ppm.m, or other set values). When the concentration data is less than or equal to the set concentration value, the control unit controls the explosion-proof pan / tilt head to continue to execute the cruise mode, so as to avoid interference with the laser gas detector caused by the edge of the metal surface, the water surface and other areas; and when the concentration data is greater than the set concentration value, the control unit controls the explosion-proof pan / tilt head to suspend operation and controls the infrared thermal imager to start the global minimum temperature detection within the thermal imaging area. Then, the control unit controls the explosion-proof pan / tilt head to rotate so that the center of the thermal imaging area of ​​the infrared thermal imager is located in the global minimum temperature area within the thermal imaging area and executes the scanning mode.The scanning mode is that the high-definition camera captures the picture of the current shooting area and transmits it to the control unit. The control unit uses the geometric center of the picture as the origin coordinate to define a reference plane coordinate system and maps it with the current shooting area. The control unit controls the explosion-proof pan / tilt to synchronously drive the laser gas detector, infrared thermal imager and high-definition camera to rotate up, down, left and right by a set angle (such as 5 degrees each for up, down, left and right, or other degrees) based on the current position, and the explosion-proof pan / tilt returns to the current position after each rotation action is implemented. During the rotation process, the center of the shooting area of ​​the high-definition camera is always moved along the coordinate axis of the reference plane coordinate system, and after each movement, the center of the shooting area returns to the origin coordinate of the reference plane coordinate system. The laser gas detector and the infrared thermal imager transmit the real-time concentration data of the suspected methane gas detected during the rotation process and the real-time temperature data of the center of the thermal imaging area to the control unit, and the control unit The center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data are recorded. The control unit then determines that when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is less than or equal to a set deviation distance, the origin coordinates are determined as the methane gas leakage point; otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is greater than the set deviation distance, the control unit calculates a midpoint coordinate based on the reference plane coordinate system according to the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value, and controls the explosion-proof pan / tilt head to rotate so that the center of the shooting area of ​​the high-definition camera coincides with the midpoint coordinate, and then re-implements the above-mentioned scanning mode until the methane gas leakage point is determined.

[0032] Furthermore, in the composite detection system of the present invention, the laser detection path of the laser gas detector and the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are on the same plane and are close to each other within the same central area, that is, the detection devices should be as close as possible in structure, so as to improve the consistency of the effective detection range of the above-mentioned detection devices.

[0033] In addition, in the reference plane coordinate system, the center coordinates of the shooting area when the real-time concentration data is the highest value are set to (X1, Y1), the center coordinates of the shooting area when the real-time temperature data is the lowest value are set to (X2, Y2), and the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is set to (X2, Y2). Midpoint coordinates

[0034] Furthermore, the composite detection system of the present invention may also include a remote terminal 70 and an alarm device (not shown). Figure 3 As shown, the remote terminal 70 has a storage unit 71 and stores environmental characteristic data, and the control unit 40 located on the explosion-proof pan-tilt platform 50 is electrically connected to the remote terminal 70 through a wired or wireless data communication method. The high-definition camera is a network high-definition zoom camera, which can perform zoom shooting according to the control instructions of the remote terminal 70 transmitted via the control unit 40 and transmit the captured image to the remote terminal 70 through the control unit 40 for storage, and the remote terminal 70 can perform feature recognition on the captured image according to the environmental characteristic data to determine the location information of the captured image. By storing the captured image, not only can the traceability of the accident be ensured, but also the intelligence level of the composite detection system can be improved through feature recognition technology. The alarm device is installed on the explosion-proof pan-tilt platform and is electrically connected to the control unit. When the control unit determines the methane gas leakage point, the alarm device can be controlled to alarm, thereby improving the timeliness of the disposal of the methane gas leakage point.

[0035] As described above, the composite detection system of the present invention integrates the laser gas detector, infrared thermal imager, high-definition camera and explosion-proof pan-tilt into a sled structure, so that the rotation, upward and downward operation detection are uniformly carried out under the operation of the explosion-proof pan-tilt, and each detection device is not an independent detection operation, but a linkage mechanism is added between each detection device, so that the detection data of each detection device can be complementary and verified, so as to improve the detection accuracy of the composite detection system. The laser detection path of the laser gas detector and the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are in the same central area, which can ensure that the effective detection range of the above detection device has a high consistency. The present invention also makes a comprehensive application of the detection data of the above detection device, so that the qualitative analysis and the quantitative analysis complement each other, and through the integration of technology to comprehensively analyze a variety of detection data, the composite detection system can timely and accurately determine the leakage point of methane gas, thereby providing decision makers with more valuable judgment basis in terms of both prevention and accident tracing.

[0036] The detection method for detecting methane gas leakage provided by the present invention comprises the following steps:

[0037] Historical temperature data collection: The explosion-proof PTZ drives the infrared thermal imager to collect historical temperature data of the entire area of ​​the surrounding environment;

[0038] Cruise detection: The laser gas detector, infrared thermal imager and high-definition camera are driven by the explosion-proof pan / tilt to detect the surrounding environment in cruise mode, and the laser detection path of the laser gas detector is within the same central area as the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located;

[0039] Abnormal situation filtering: When the infrared thermal imager detects that the temperature data of an area is lower than the historical temperature data of the area, the laser gas detector detects the concentration data of the suspected methane gas in the area. When the concentration data is less than or equal to a set concentration value, the above cruise detection steps are continued;

[0040] Abnormal situation scanning: when the concentration data is greater than the set concentration value, the explosion-proof pan / tilt stops running, the infrared thermal imager starts the global minimum temperature detection within the thermal imaging area, and the explosion-proof pan / tilt rotates to move the center of the thermal imaging area of ​​the infrared thermal imager to the global minimum temperature area to perform abnormal scanning. The abnormal scanning is that the high-definition camera captures the picture of the current shooting area, and defines a reference plane coordinate system with the geometric center of the picture as the origin coordinate and maps it with the current shooting area. Then, the explosion-proof pan / tilt drives the laser gas detector, the infrared thermal imager and the high-definition camera to rotate up, down, left and right by a set angle based on the current position, and the explosion-proof pan / tilt returns to the current position after each rotation action is implemented. During the rotation process, the center of the shooting area of ​​the high-definition camera always moves along the coordinate axis of the reference plane coordinate system, and after each movement, the center of the shooting area returns to the origin coordinate of the reference plane coordinate system. The laser gas detector and the infrared thermal imager collect the real-time concentration data of the suspected methane gas detected during the rotation process and the real-time temperature data of the center of the thermal imaging area, and determine the center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data.

[0041] Determine the methane gas leakage point: when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is less than or equal to a set deviation distance, the origin coordinates are determined as the methane gas leakage point; otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is greater than the set deviation distance, a midpoint coordinate based on the reference plane coordinate system is calculated based on the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value, the explosion-proof pan / tilt rotates to make the center of the shooting area of ​​the high-definition camera coincide with the midpoint coordinate, and then the above-mentioned abnormal scan is performed until the methane gas leakage point is determined.

[0042] Furthermore, in the above step of determining the methane gas leakage point, the center coordinates of the shooting area when the real-time concentration data is the highest value are set as (X1, Y1), and the center coordinates of the shooting area when the real-time temperature data is the lowest value are set as (X2, Y2) in the reference plane coordinate system. Then, the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is Midpoint coordinates

[0043] Furthermore, after the above-mentioned cruise detection step, it also includes an image preservation and location identification step: the image captured by the high-definition camera is transmitted to the remote terminal for storage, and the remote terminal can identify the image features based on the environmental feature data to determine the image location information. This can not only ensure the ability to trace the accident, but also improve the intelligence level of location information identification and facilitate the timely disposal of the gas leakage area. And after the above-mentioned methane gas leakage point determination step, it also includes a leakage alarm step: after the methane gas leakage point is determined, a leakage alarm is performed. This can improve the timeliness of the disposal of the methane gas leakage point.

[0044] By analyzing the historical temperature data of the surrounding environment of the process unit area through the detection method of the present invention, the area suspected of methane gas leakage can be discovered in time, and the situation that interferes with the detection result can be eliminated in time through the abnormal situation filtering step, thereby effectively improving the accuracy of the detection result. The detection method of the present invention also enables the detection data of each detection device to be complementary and verified by unifying the operation detection and linkage of each detection device, and by comprehensively applying each detection data, the qualitative analysis and the quantitative analysis can complement each other, so that the detection results are more accurate and reliable, so that the leakage point of methane gas can be determined in time and accurately, and more valuable judgment basis can be provided to decision makers in terms of both prevention and accident tracing.

[0045] The present invention also provides a computer storage medium, which stores a program (software) capable of executing the above detection method.

[0046] In addition, in order to save energy and reduce consumption, when the explosion-proof pan / tilt head executes the cruise mode, the composite detection system of the present invention can enable the infrared thermal imager and the high-definition camera or only the infrared thermal imager to be fully turned on to record the conditions (temperature, images) on the cruise route, and the laser gas detector can be temporarily turned off; and when the infrared thermal imager detects an abnormal situation, the laser gas detector can be turned on again to perform gas concentration detection.

[0047] The above technical scheme of the present invention has broad application prospects in natural gas stations with high hazard levels (high safety requirements), high operating pressures and many low-temperature environments (such as high-sulfur natural gas stations, gas pipeline stations, natural gas processing plants and LNG stations, etc.).

[0048] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Other equivalent changes made using the patent concept of the present invention should all fall within the patent protection scope of the present invention.

Claims

1. A composite detection system for detecting methane gas leakage, comprising: A laser gas detector, an infrared thermal imager, a high-definition camera, an explosion-proof pan-tilt and a control unit; the laser gas detector, the infrared thermal imager and the high-definition camera are all installed on the explosion-proof pan-tilt and driven by the explosion-proof pan-tilt to perform a uniform circumferential rotation and an upward or downward tilt at the same angle, and the laser detection path of the laser gas detector and the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located are within the same central area; the control unit is installed on the explosion-proof pan-tilt and is electrically connected to the laser gas detector, the infrared thermal imager, the high-definition camera and the explosion-proof pan-tilt respectively; the explosion-proof pan-tilt normally executes a cruise mode, and when the infrared thermal imager detects that the temperature data of an area is less than a historical temperature data of the area, the laser gas detector detects the concentration data of the suspected methane gas in the area and transmits it to the control unit, the control unit compares the concentration data with a set concentration value, and when the concentration data is less than or equal to the set concentration value, the control unit controls the explosion-proof pan-tilt to continue to execute the cruise mode;It is characterized in that when the concentration data is greater than the set concentration value, the control unit controls the explosion-proof pan / tilt to suspend operation and controls the infrared thermal imager to start the global minimum temperature detection within the thermal imaging area. After that, the control unit controls the explosion-proof pan / tilt to rotate so that the center of the thermal imaging area of ​​the infrared thermal imager is located in the global minimum temperature area within the thermal imaging area and executes the scanning mode. The scanning mode is that the high-definition camera captures the picture of the current shooting area and transmits it to the control unit. The control unit uses the geometric center of the picture as the origin coordinate to define a reference plane coordinate system and maps it with the current shooting area. The control unit controls the explosion-proof pan / tilt to synchronously drive the laser gas detector, the infrared thermal imager and the high-definition camera to rotate up, down, left and right by a set angle based on the current position, and the explosion-proof pan / tilt returns to the current position after each rotation action is implemented. In the rotation process, the center of the shooting area of ​​the high-definition camera always moves along the coordinate axis of the reference plane coordinate system, and after each movement, the center of the shooting area returns to the origin coordinate of the reference plane coordinate system. The laser gas detector and the infrared thermal imager are The imager transmits the real-time concentration data of the suspected methane gas and the real-time temperature data of the center of the thermal imaging area detected during the rotation process to the control unit, and the control unit records the center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data. The control unit then determines that when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is less than or equal to a set deviation distance, the origin coordinate is determined as the methane gas leakage point. Otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value is greater than the set deviation distance, the control unit calculates a midpoint coordinate based on the reference plane coordinate system according to the center coordinates of the shooting area when the real-time concentration data is the highest value and the center coordinates of the shooting area when the real-time temperature data is the lowest value, and controls the explosion-proof pan / tilt to rotate so that the center of the shooting area of ​​the high-definition camera coincides with the midpoint coordinate, and then re-implements the above scanning mode until the methane gas leakage point is determined. ; 2. The composite detection system according to claim 1, characterized in that: The laser detection path of the laser gas detector, the straight line where the center of the thermal imaging area of ​​the infrared thermal imager is located, and the straight line where the center of the shooting area of ​​the high-definition camera is located are on the same plane and are close to each other within the same central area.

3. The composite detection system according to claim 1, characterized in that: The center coordinates of the shooting area when the real-time concentration data is at the highest value are (X1, Y1), the center coordinates of the shooting area when the real-time temperature data is at the lowest value are (X2, Y2), and the distance between the center coordinates of the shooting area when the real-time concentration data is at the highest value and the center coordinates of the shooting area when the real-time temperature data is at the lowest value is (X2, Y2). Midpoint coordinates (X3, Y3), 4. The composite detection system according to claim 1, characterized in that: Also includes: A remote terminal, wherein the remote terminal has a storage unit and stores environmental characteristic data, the control unit is electrically connected to the remote terminal via a wired or wireless data communication method, the high-definition camera is a network high-definition zoom camera, the network high-definition zoom camera can perform zoom shooting according to the control command of the remote terminal transmitted via the control unit and transmit the captured image to the remote terminal through the control unit for storage, and the remote terminal can perform feature recognition on the captured image according to the environmental characteristic data to determine the location information of the captured image.

5. The composite detection system according to claim 1, characterized in that: Also includes: An alarm device is installed on the explosion-proof pan / tilt platform and is electrically connected to the control unit. When the control unit determines a methane gas leakage point, the alarm device is controlled to sound an alarm.

6. A method for detecting methane gas leakage, characterized in that the steps include: Historical temperature data collection: The explosion-proof PTZ drives the infrared thermal imager to collect historical temperature data of the entire area of ​​the surrounding environment; Cruise detection: The laser gas detector, infrared thermal imager and high-definition camera are driven by the explosion-proof pan / tilt to detect the surrounding environment in cruise mode, and the laser detection path of the laser gas detector is within the same central area as the straight line where the center of the thermal imaging area of ​​the infrared thermal imager and the straight line where the center of the shooting area of ​​the high-definition camera are located; Abnormal situation filtering: when the infrared thermal imager detects that the temperature data of an area is less than the historical temperature data of the area, the laser gas detector detects the concentration data of the suspected methane gas in the area. When the concentration data is less than or equal to a set concentration value, the above-mentioned cruise detection step is continued; Abnormal situation scanning: when the concentration data is greater than the set concentration value, the explosion-proof pan / tilt stops running, the infrared thermal imager starts the global minimum temperature detection within the thermal imaging area, and the explosion-proof pan / tilt rotates to move the center of the thermal imaging area of ​​the infrared thermal imager to the global minimum temperature area to perform abnormal scanning. The abnormal scanning is performed by the high-definition camera capturing a picture of the current shooting area, defining a reference plane coordinate system with the geometric center of the picture as the origin coordinate and mapping it with the current shooting area, and then the explosion-proof pan / tilt synchronously drives the laser gas detector, infrared thermal imager and high-definition camera upward and downward respectively based on the current position. The explosion-proof pan / tilt head rotates downward, leftward, and rightward by a set angle and returns to the current position after each rotation action is performed, and the center of the shooting area of ​​the high-definition camera always moves along the coordinate axis of the reference plane coordinate system during the rotation process and returns to the origin coordinate of the reference plane coordinate system after each movement, and the laser gas detector and the infrared thermal imager collect the real-time concentration data of the suspected methane gas and the real-time temperature data of the center of the thermal imaging area detected during the rotation process, and determine the center coordinates of the shooting area corresponding to the highest value of the real-time concentration data and the center coordinates of the shooting area corresponding to the lowest value of the real-time temperature data; Determine the methane gas leakage point: when the distance between the center coordinates of the shooting area when the real-time concentration data is at the highest value and the center coordinates of the shooting area when the real-time temperature data is at the lowest value is less than or equal to a set deviation distance, the origin coordinates are determined as the methane gas leakage point; otherwise, when the distance between the center coordinates of the shooting area when the real-time concentration data is at the highest value and the center coordinates of the shooting area when the real-time temperature data is at the lowest value is greater than the set deviation distance, a midpoint coordinate based on the reference plane coordinate system is calculated according to the center coordinates of the shooting area when the real-time concentration data is at the highest value and the center coordinates of the shooting area when the real-time temperature data is at the lowest value, the explosion-proof pan / tilt rotates so that the center of the shooting area of ​​the high-definition camera coincides with the midpoint coordinate, and then the above-mentioned abnormal scan is performed until the methane gas leakage point is determined.

7. The detection method according to claim 6, characterized in that: The center coordinates of the shooting area when the real-time concentration data is at the highest value are (X1, Y1), the center coordinates of the shooting area when the real-time temperature data is at the lowest value are (X2, Y2), and the distance between the center coordinates of the shooting area when the real-time concentration data is at the highest value and the center coordinates of the shooting area when the real-time temperature data is at the lowest value is (X2, Y2). Midpoint coordinates (X3, Y3), 8. The detection method according to claim 6, characterized in that: After the cruise detection step, it also includes: Image preservation and location identification: The image captured by the high-definition camera is transmitted to a remote terminal for storage, and the remote terminal can perform feature identification on the image based on environmental feature data to determine the location information of the image.

9. The detection method according to claim 6, characterized in that: After determining the methane gas leak point, the following steps are also included: Leakage alarm: After the methane gas leakage point is determined, the leakage alarm will be activated.

10. A computer storage medium, characterized in that: The computer storage medium stores a program, and the program executes the detection method according to any one of claims 6 to 9.

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