A contactless detection method and apparatus for methane gas leaks

Abstract

The application provides a kind of methane gas leakage non-contact detection method and equipment, it is related to gas detection technical field, methane gas leakage non-contact detection equipment includes the ring body being arranged in the gas storage cabinet outside, lifting part, the gas storage cabinet has the outer membrane of spherical shell shape, the axis of ring body coincides with the vertical axis of outer membrane, is equipped with emitting module and receiving module on ring body, the inner wall of ring body is reflection surface, infrared light beam generated by emitting module is received by receiving module after reflection by the inner wall of ring body, to form annular detection area between outer membrane and ring body, simultaneously, lifting part controls ring body to lift, makes detection area lift to cover the outer surface of outer membrane, to realize the detection range of comprehensive coverage type to the outer surface of spherical shell shape outer membrane, can capture low concentration, fast dissipation leakage in time, to a certain extent, avoid detection delay or miss detection.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and in particular to a non-contact detection method and equipment for methane gas leaks. Background Technology

[0002] Methane, as an important gaseous fuel and chemical feedstock, poses a risk of combustion and explosion when mixed with air and exposed to an open flame. Therefore, ensuring the airtightness of storage facilities and preventing leaks during its storage and use is crucial for safe production and environmental protection. Independent double-membrane gas holders are common storage facilities for gases such as methane. Their structure typically includes an outer membrane, an inner membrane, and a bottom membrane, and is equipped with components such as rangefinders, fans, and control cabinets to monitor the gas holder's status in real time and regulate internal pressure, thereby indirectly assessing the gas holder's integrity. In existing technologies, methane leak detection methods have gradually evolved from traditional contact sensors (such as electrochemical or catalytic combustion sensors) to non-contact technologies, such as detection systems based on infrared optics. These systems utilize methane's absorption characteristics in specific infrared bands, using laser or thermal imaging equipment to achieve long-distance, non-invasive leak identification, providing early warnings without interfering with facility operation, thus improving safety management.

[0003] In areas with stringent environmental regulations, even a minor leak in the outer membrane of a dual-membrane gas storage tank can cause the released methane to rapidly diffuse and dilute. Traditional handheld methane remote sensors, due to their limited detection range, struggle to detect such low-concentration, rapidly dissipating leaks in a timely manner, often leading to detection delays or missed detections.

[0004] The information disclosed in the background section of this invention is intended only to enhance the understanding of the general background of this invention, and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] Therefore, it is necessary to provide a non-contact detection method and equipment for methane gas leakage, addressing the problems existing in current handheld methane remote sensing instruments.

[0006] The above objectives are achieved through the following technical solutions:

[0007] A non-contact detection device for methane gas leakage includes an annular body and a lifting unit disposed outside a gas storage tank. The gas storage tank has a spherical outer membrane. The axis of the annular body coincides with the vertical axis of the outer membrane. The annular body is provided with a transmitting module and a receiving module. The inner wall of the annular body is a reflective surface. The infrared beam generated by the transmitting module is reflected by the inner wall of the annular body and received by the receiving module to form an annular detection area between the outer membrane and the annular body. The lifting unit is used to control the raising and lowering of the annular body so that the detection area rises and falls to cover the outer surface of the outer membrane.

[0008] Furthermore, the annular detection area has a radial thickness, the transmitting module has a first adjustment part, which is used to adjust the orientation of the transmitting module to change the radial thickness of the detection area; the receiving module has a second adjustment part, which is used to adjust the orientation of the receiving module; the transmitting module is fixed relative to the ring body, and a rotating part is also provided outside the gas storage tank, which is used to control the receiving module to move along the trajectory of the ring body.

[0009] Furthermore, the intersection of the infrared beam and the inner wall of the ring is the reflection point. The ratio of the arc length of the two farthest and adjacent reflection points in the circumference of the ring to the circumference of the inner wall of the ring is k. When k is greater than or equal to a preset value, the rotating part controls the transmitting module to rotate synchronously with the ring. When k is less than the preset value, the rotating part controls the transmitting module to remain stationary with the ring.

[0010] Furthermore, the launch module has a first velocity when it rotates synchronously with the ring body, and the first velocity is positively correlated with k.

[0011] Furthermore, the transmitting module has an adjustment module for regulating its power, which is positively correlated with the number of reflection points.

[0012] Furthermore, the infrared beam emitted by the transmitting module has a first frequency, and the infrared beam received by the receiving module has a second frequency. When the second frequency differs from the first frequency, the first adjustment unit adjusts the orientation of the transmitting module to reduce the radial thickness of the detection area.

[0013] Furthermore, when the second frequency differs from the first frequency, the rotating part controls the receiving module to move along the trajectory of the ring, and the second adjusting part adjusts the orientation of the receiving module to increase the number of reflection points.

[0014] Furthermore, the heights of the transmitting module and the receiving module differ.

[0015] Furthermore, the lifting unit includes multiple lifting cylinders evenly distributed along the circumference of the ring body, with the ring body rotatably positioned at the output end of all the lifting cylinders.

[0016] This invention also provides the following technical solutions:

[0017] A non-contact detection method for methane gas leaks, comprising the following steps:

[0018] The transmitting and receiving modules are activated. The infrared beam generated by the transmitting module is reflected by the inner wall of the ring and received by the receiving module to form a ring-shaped detection area between the outer membrane and the ring body, so as to detect methane leakage within the detection area.

[0019] Start the lifting unit, which drives the ring body to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane.

[0020] The present invention has at least the following beneficial effects:

[0021] (1) The infrared beam generated by the transmitting module is reflected by the inner wall of the ring and received by the receiving module to form a ring-shaped detection area between the outer membrane and the ring. At the same time, the lifting part controls the ring to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane, thereby achieving a comprehensive detection range covering the outer surface of the spherical outer membrane. This can capture low-concentration, rapidly dissipating leaks in a timely manner and avoid detection delays or missed detections to a certain extent.

[0022] (2) The orientation of the transmitting module is changed by the first adjustment part to change the emission angle of the infrared beam, thereby changing the radial thickness of the detection area so that the inner side of the detection area and the outer surface of the outer membrane are still at a suitable distance, so that the radial thickness of the detection area is adapted to the position after the lifting and lowering, ensuring the detection range and detection effect; at the same time, the orientation of the receiving module is changed by the second adjustment part, and the receiving module is controlled to move along the trajectory of the ring by the rotating part to ensure that the receiving module can receive the infrared beam.

[0023] (3) When k is greater than or equal to the preset value, it indicates that the infrared beam, after multiple reflections, is unevenly distributed within the detection area, resulting in a small detection range and affecting the detection effect. Therefore, by controlling the rotating part to rotate the transmitting module synchronously with the ring, the unevenly distributed infrared beam within the detection area is rotated, further ensuring the detection range and detection effect. When k is less than the preset value, it indicates that the infrared beam, after multiple reflections, is relatively evenly distributed within the detection area, resulting in a suitable detection range.

[0024] (4) When the wind blows and causes the outer membrane to shake, it may block the reflection of the infrared beam, and the leaked methane is easily diluted by the wind and difficult to detect. When there is a difference between the first frequency of the infrared beam emitted by the transmitting module and the second frequency of the infrared beam received by the receiving module, it indicates that the outer membrane is shaking and blocking the reflection of the infrared beam. The first adjustment unit adjusts the orientation of the transmitting module to reduce the radial thickness of the detection area, so that the inner side of the detection area is away from the outer surface of the outer membrane, so as to avoid the influence of the outer membrane shaking on the reflection of the infrared beam. At the same time, the number of reflections of the infrared beam is increased, so that the diluted methane can be detected. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the non-contact detection device for methane gas leakage provided in an embodiment of the present invention;

[0026] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0027] Figure 3 for Figure 1 A cross-sectional view of the central ring body;

[0028] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0029] Figure 5 for Figure 4 A magnified view of a section at point C;

[0030] Figure 6 This is a schematic diagram of the detection area;

[0031] Figure 7 for Figure 6 A schematic diagram showing the radial thickness of the detection area after reduction;

[0032] Figure 8 for Figure 7 A schematic diagram showing the radial thickness of the detection area after reduction;

[0033] Figure 9 for Figure 8 A schematic diagram showing the radial thickness of the detection area after reduction.

[0034] in:

[0035] 101. Outer membrane;

[0036] 201. Ring body; 202. Transmitting module; 203. Receiving module; 204. Adjusting motor; 205. First support; 206. Second support; 207. First motor; 208. First gear; 209. First gear ring; 210. Second motor; 211. Second gear; 212. Second gear ring; 213. First wire; 214. First contact; 215. First conductive ring; 216. Second wire; 217. Second conductive ring; 218. Third wire; 219. Second contact; 220. Branch wire; 221. Lifting cylinder. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0038] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] like Figures 1 to 9 As shown, this embodiment of the invention provides a non-contact detection device for methane gas leakage, including an annular body 201 disposed outside a gas storage tank and a lifting unit. The gas storage tank has a spherical outer membrane 101. The axis of the annular body 201 coincides with the vertical axis of the outer membrane 101. The annular body 201 is provided with a transmitting module 202 and a receiving module 203. The inner wall of the annular body 201 is a reflective surface. The infrared beam generated by the transmitting module 202 is reflected by the inner wall of the annular body 201 and received by the receiving module 203 to form an annular detection area between the outer membrane 101 and the annular body 201. The lifting unit is used to control the lifting and lowering of the annular body 201 so that the detection area is raised and lowered to cover the outer surface of the outer membrane 101.

[0041] The infrared beam generated by the transmitting module 202 is reflected by the inner wall of the ring body 201 and received by the receiving module 203 to form a ring-shaped detection area between the outer membrane 101 and the ring body 201. At the same time, the lifting part controls the ring body 201 to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane 101, thereby achieving a comprehensive detection range covering the outer surface of the spherical outer membrane 101. This can promptly capture low-concentration, rapidly dissipating leaks and, to a certain extent, avoid detection delays or missed detections.

[0042] The gas storage tank includes a bottom membrane, an inner membrane, and a constant pressure control system. The bottom membrane is fixed to a cement base by steel rails, forming a basic seal to prevent gas leakage and supporting the inner and outer membranes 101. The inner membrane is connected to the edge of the bottom membrane, forming an independent sealed space for storing gases (such as methane). The outer membrane 101 is connected to the edge of the bottom membrane, covering the inner membrane to form a spherical shell, and forms a pressure regulating space with the inner membrane, protecting the inner membrane and maintaining the shape of the tank. The constant pressure control system, as the core control unit, typically includes a control cabinet, pressure sensors, fans, and safety valves, used to automatically maintain stable pressure inside the gas tank. When the gas to be stored enters the inner membrane space, the inner membrane expands. To counteract the potential increase in pressure due to the increased gas volume, the constant pressure control system activates, discharging an appropriate amount of air from the pressure regulating space between the outer membrane 101 and the inner membrane, making room for the expansion of the inner membrane, thereby maintaining the gas pressure within the inner membrane within a set range. When the internally stored gas is depleted, the inner membrane contracts. The constant pressure control system activates the fan to inject air into the pressure regulating space, thereby supporting the outer membrane 101 through air pressure, maintaining its rigidity and spherical shape. Simultaneously, the injected air pressure compresses the inner membrane, ensuring that the remaining gas within the inner membrane maintains sufficient output pressure, guaranteeing stable gas delivery. Additionally, the receiving module 203 can receive infrared beams and sense their intensity. This application also includes a processor for analyzing the intensity signal of the infrared beam received by the receiving module 203 and calculating leakage information related to methane concentration. The structural composition and working principle of the aforementioned independent dual-membrane gas storage tank, as well as the specific settings of the transmitting module 202, receiving module 203, and processor, are all prior art and will not be elaborated upon here. The inner wall of the annular body 201 is equipped with a reflector to form a reflective surface for infrared beams.

[0043] In one embodiment, see Figures 6 to 9 The annular detection area has a radial thickness. The transmitting module 202 has a first adjustment part, which is used to adjust the orientation of the transmitting module 202 to change the radial thickness of the detection area. The receiving module 203 has a second adjustment part, which is used to adjust the orientation of the receiving module 203. The transmitting module 202 is fixed relative to the ring body 201. A rotating part is also provided outside the gas storage tank, which is used to control the receiving module 203 to move along the trajectory of the ring body 201.

[0044] The inner side of the detection area needs to maintain a suitable distance from the outer surface of the outer membrane 101 so that the radial thickness of the detection area is adapted to its position. When the lifting part raises or lowers the detection area, the distance between the inner side of the detection area and the outer surface of the outer membrane 101 changes, and the radial thickness of the detection area is not adapted to the position after the raising or lowering, affecting the detection range and detection effect. Therefore, the first adjustment part changes the orientation of the transmitting module 202 to change the emission angle of the infrared beam, thereby changing the radial thickness of the detection area so that the inner side of the detection area still maintains a suitable distance from the outer surface of the outer membrane 101, and the radial thickness of the detection area is adapted to the position after the raising or lowering, ensuring the detection range and detection effect; at the same time, the second adjustment part changes the orientation of the receiving module 203, and the rotating part controls the receiving module 203 to move along the trajectory of the ring body 201 to ensure that the receiving module 203 can receive the infrared beam.

[0045] Specifically, the radial thickness of the detection area is Figures 6 to 9 The infrared beam is distributed within the range between the dotted circular line and the inner wall of the ring 201. The inner side of the detection area needs to maintain a suitable distance from the outer surface of the outer membrane 101, for example, this distance is 'a'. Since the outer membrane 101 is spherical, its diameter gradually changes from bottom to top. When the lifting unit raises the detection area, the distance between the inner side of the detection area and the outer surface of the outer membrane 101 is greater than 'a', resulting in a smaller radial thickness of the detection area and poorer detection range and effect. Therefore, the first adjustment unit changes the orientation of the emission module 202 to increase the radial thickness of the detection area, reducing the distance between the inner side of the detection area and the outer surface of the outer membrane 101 to 'a'. It can be understood that during the process of the lifting unit raising the detection area, the radial thickness of the detection area gradually increases; during the process of the lifting unit lowering the detection area, the radial thickness of the detection area gradually decreases, ensuring that the distance between the inner side of the detection area and the outer surface of the outer membrane 101 remains at 'a', thus guaranteeing the detection range and effect.

[0046] In addition, each time the first adjustment unit adjusts the orientation of the transmitting module 202, the second adjustment unit must adjust the orientation of the receiving module 203, and the rotating unit controls the receiving module 203 to move along the trajectory of the ring 201 to ensure that the receiving module 203 can receive the infrared beam.

[0047] Among them, see Figure 4 and Figure 5The first and second adjustment units have the same structure, each including two adjustment motors 204 with mutually perpendicular output ends. One adjustment motor 204 has a vertical output end and is used to drive the transmitting module 202 or the receiving module 203 to rotate horizontally to perform a tilting motion, thereby changing the orientation of the transmitting module 202 or the receiving module 203 in the horizontal direction. The other adjustment motor 204 has a horizontal output end and is used to drive the transmitting module 202 or the receiving module 203 to rotate vertically to perform a pitching motion, thereby changing the orientation of the transmitting module 202 or the receiving module 203 in the vertical direction. A first support 205 for mounting the transmitting module 202 is fixed at the lower part of the ring body 201, and a second support 206 for mounting the receiving module 203 is provided at the upper part of the ring body 201. The second support 206 and the ring body 201 are slidably engaged through a guide rail structure, allowing the second support 206 to move along the trajectory of the ring body 201. The rotating part includes a first motor 207 and a first gear 208 and a first gear ring 209 that mesh with each other. The first motor 207 is mounted on a second support 206. The output end of the first motor 207 is fixed to the first gear 208. The first gear ring 209 is fixed to the upper surface of the ring body 201. The output end of the first motor 207 drives the first gear 208 to rotate, so that the second support 206 drives the receiving module 203 to move along the trajectory of the ring body 201.

[0048] In one embodiment, the intersection of the infrared beam and the inner wall of the ring 201 is the reflection point. The ratio of the arc length of the two farthest and adjacent reflection points on the circumference of the ring 201 to the circumference of the inner wall of the ring 201 is k. When k is greater than or equal to a preset value, the rotating part controls the transmitting module 202 to rotate synchronously with the ring 201. When k is less than the preset value, the rotating part controls the transmitting module 202 to remain stationary with the ring 201.

[0049] When the radial thickness of the detection area is changed, the distribution of the infrared beam, after multiple reflections, within the detection area cycles between uniform and non-uniform. The position of the reflection point formed by the infrared beam and the inner wall of the ring 201 also changes accordingly, causing k to change. When k is greater than or equal to a preset value, it indicates that the distribution of the infrared beam, after multiple reflections, within the detection area is uneven, resulting in a small detection range and affecting the detection effect. Therefore, the emitting module 202 is controlled to rotate synchronously with the ring 201 via a rotating part, causing the unevenly distributed infrared beam within the detection area to rotate, further ensuring the detection range and detection effect. When k is less than the preset value, it indicates that the distribution of the infrared beam, after multiple reflections, within the detection area is relatively uniform, and the detection range of the infrared beam is suitable. Therefore, the emitting module 202 and the ring 201 remain stationary.

[0050] It is understandable that among all reflection points, there is a ratio between the arc length of two adjacent reflection points and the circumference of the inner wall of the ring 201. However, it is only necessary to determine the relationship between k and the preset value. That is, as long as k is greater than or equal to the preset value, it indicates that the distribution of the infrared beam that has undergone multiple reflections in the detection area is uneven. In addition, the size of the preset value can be set to adjust the sensitivity of the synchronous rotation of the transmitting module 202 and the ring 201. For example, the larger the preset value, the less likely the transmitting module 202 and the ring 201 are to trigger synchronous rotation; the smaller the preset value, the easier it is for the transmitting module 202 and the ring 201 to trigger synchronous rotation.

[0051] The rotating part also includes a second motor 210 and a meshing second gear 211 and a second gear ring 212. The second motor 210 is mounted on the second support 206, and its output end is fixed to the second gear 211. The second gear ring 212 is fixed to the lower surface of the ring body 201. The output end of the second motor 210 drives the second gear 211 to rotate, causing the first support 205, the ring body 201, and the launching module 202 to rotate synchronously. Additionally, the second support 206 is provided with a first wire 213, one end of which is connected to an external power source, and the other end is connected to a first contact 214. A first conductive ring 215 is coaxially mounted on the lower surface of the ring body 201, contacting the first contact 214. A second wire 216 is located inside the ring body 201, one end of which contacts the first conductive ring 215, and the other end is provided with a second conductive ring 217. The first support... The first support 205 is equipped with a third wire 218 and a second contact 219. The second contact 219 is located at one end of the third wire 218 and contacts the second conductive ring 217. The other end of the third wire 218 forms multiple branch wires 220, which are used to supply power to the first motor 207, the receiving module 203, and the regulating motor 204 of the receiving module 203. This ensures that the relevant electrical components are powered even when the first support 205 moves along the trajectory of the ring 201. The second motor 210 is also connected to an external power source via a wire. The transmitting module 202, the receiving module 203, the regulating motor 204, the first motor 207, and the second motor 210 are all equipped with control modules. All control modules are connected to a processor to control start-up, shutdown, and operating conditions.

[0052] It is understood that the first adjustment unit adjusts the orientation of the emitting module 202. Each orientation of the emitting module 202 corresponds one-to-one with the path of its infrared beam. The processor of this application can simulate the path of the infrared beam emitted by the emitting module 202 based on its orientation, thereby obtaining the reflection points formed by the infrared beam on the inner wall of the ring 201 and related information of the reflection points, such as the number of reflection points and the arc length of two adjacent reflection points.

[0053] In one embodiment, the transmitting module 202 has a first speed when it rotates synchronously with the ring 201, and the first speed is positively correlated with k.

[0054] The larger the value of k, the more uneven the distribution of the infrared beam after multiple reflections within the detection area. Therefore, a larger initial velocity is required to further ensure the detection range and detection effect, in order to adapt to high-precision detection scenarios.

[0055] In one embodiment, the transmitting module 202 has an adjustment module for adjusting its power, the power of the transmitting module 202 being positively correlated with the number of reflection points.

[0056] The rotating part controls the receiving module 203 to move along the trajectory of the ring 201 to receive the infrared beam after a suitable number of reflections. The power of the transmitting module 202 is adjusted by the adjusting module to adapt to the number of reflections of the infrared beam. That is, when the number of reflections increases, the power of the transmitting module 202 needs to be increased to ensure that the infrared beam can still be effectively received by the receiving module 203 after multiple reflections and attenuation.

[0057] It is understood that the processor of this application can adjust the power of the transmitting module 202 according to the number of reflection points, so that within a certain range, the greater the number of transmission points, the greater the power of the transmitting module 202.

[0058] In one embodiment, the infrared beam emitted by the transmitting module 202 has a first frequency, and the infrared beam received by the receiving module 203 has a second frequency. When the second frequency differs from the first frequency, the first adjustment unit adjusts the orientation of the transmitting module 202 to reduce the radial thickness of the detection area.

[0059] When the wind blows and causes the outer membrane 101 to shake, it may block the reflection of the infrared beam. When there is a difference between the first frequency of the infrared beam emitted by the transmitting module 202 and the second frequency of the infrared beam received by the receiving module 203, it indicates that the outer membrane 101 is shaking and blocking the reflection of the infrared beam. The first adjustment unit adjusts the orientation of the transmitting module 202 to reduce the radial thickness of the detection area, so that the inner side of the detection area is away from the outer surface of the outer membrane 101, so as to avoid the influence of the shaking of the outer membrane 101 on the reflection of the infrared beam.

[0060] It is understood that the processor of this application can obtain the first frequency of the infrared beam emitted by the transmitting module 202 and the second frequency of the infrared beam received by the receiving module 203, and compare the first frequency and the second frequency. When there is a difference between the two, the processor controls the first adjustment unit to operate in order to adjust the orientation of the transmitting module 202, thereby reducing the radial thickness of the detection area.

[0061] In one embodiment, when the second frequency differs from the first frequency, the rotating part controls the receiving module 203 to move along the trajectory of the ring 201, and the second adjusting part adjusts the orientation of the receiving module 203 to increase the number of reflection points.

[0062] When the wind blows and causes the outer membrane 101 to shake, the leaked methane is easily diluted by the wind and becomes difficult to detect. This reduces the radial thickness of the detection area and increases the number of reflections of the infrared beam, thus enabling the detection of diluted methane.

[0063] It is understandable that by controlling the rotating part to move the receiving module 203 along the trajectory of the ring body 201, the position of the receiving module 203 on the trajectory of the ring body 201 is changed. At the same time, the second adjusting part adjusts the orientation of the receiving module 203 accordingly, so as to ensure that the receiving module 203 can receive the infrared beam, thereby changing the number of reflection points, that is, the number of reflections of the infrared beam.

[0064] In one embodiment, the heights of the transmitting module 202 and the receiving module 203 are different to form a three-dimensional detection area, further ensuring the detection range and detection effect.

[0065] Specifically, the transmitting module 202 is lower than the receiving module 203. It is worth noting that the orientation of the transmitting module 202 can be adjusted by the first adjustment unit, causing the infrared beam to gradually rise from the reflection point formed on the inner wall of the ring 201, and finally be received by the receiving module 203. In other words, its height gradually increases from the first reflection point to the last transmission point. In other embodiments not shown, the transmitting module 202 may also be higher than the receiving module 203, while its height gradually decreases from the first reflection point to the last transmission point.

[0066] In one embodiment, the lifting unit includes a plurality of lifting cylinders 221 evenly distributed along the circumference of the ring body 201, and the ring body 201 is rotatably disposed at the output end of all the lifting cylinders 221.

[0067] The lifting cylinder 221 can be a hydraulic cylinder or an electric push rod, etc., and is equipped with a corresponding power source and control module. The control module is connected to the processor to control the start-stop and operating conditions. Each lifting cylinder 221 has a second support 206 at its output end. The ring body 201 is rotatably mounted on all the second supports 206. A second motor 210 is mounted on one of the second supports 206.

[0068] This invention also provides a non-contact detection method for methane gas leakage, comprising the following steps:

[0069] The transmitting module 202 and the receiving module 203 are activated. The infrared beam generated by the transmitting module 202 is reflected by the inner wall of the ring body 201 and received by the receiving module 203 to form a ring-shaped detection area between the outer membrane 101 and the ring body 201, so as to detect the methane leakage in the detection area.

[0070] Start the lifting unit, which drives the ring 201 to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane 101.

[0071] The working principle of this invention is as follows:

[0072] The infrared beam generated by the transmitting module 202 is reflected by the inner wall of the ring body 201 and received by the receiving module 203 to form a ring-shaped detection area between the outer membrane 101 and the ring body 201. At the same time, the lifting cylinder 221 controls the ring body 201 to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane 101, thereby achieving a comprehensive detection range covering the outer surface of the spherical outer membrane 101. This can promptly capture low-concentration, rapidly dissipating leaks and, to a certain extent, avoid detection delays or missed detections.

[0073] During the process of raising and lowering the detection area by the lifting cylinder 221, the orientation of the transmitting module 202 is changed by adjusting the motor 204 to change the emission angle of the infrared beam, thereby changing the radial thickness of the detection area. This ensures that the inner side of the detection area and the outer surface of the outer membrane 101 maintain a suitable distance, and that the radial thickness of the detection area adapts to its position after raising and lowering, thus guaranteeing the detection range and detection effect. At the same time, the orientation of the receiving module 203 is changed by adjusting the motor 204, and the output end of the first motor 207 drives the first gear 208 to rotate. The first gear 208 meshes with the first gear ring 209 to control the movement of the receiving module 203 along the trajectory of the ring body 201, so as to ensure that the receiving module 203 can receive the infrared beam.

[0074] When the radial thickness of the detection area is changed, the distribution of the infrared beam after multiple reflections within the detection area cycles between uniform and non-uniform. The position of the reflection point formed by the infrared beam and the inner wall of the ring 201 also changes accordingly, causing k to change accordingly. When k is greater than or equal to a preset value, it indicates that the distribution of the infrared beam after multiple reflections within the detection area is uneven, resulting in a smaller detection range and affecting the detection effect. Therefore, the output of the second motor 210 drives the second gear 211 to rotate. The second gear 211 meshes with the second gear ring 212 to control the transmitting module 202 and the ring 201 to rotate synchronously at a first speed, causing the unevenly distributed infrared beam within the detection area to rotate. Furthermore, the larger k is, the larger the required first speed, further ensuring the detection range and detection effect. When k is less than the preset value, it indicates that the distribution of the infrared beam after multiple reflections within the detection area is relatively uniform, and the detection range of the infrared beam is suitable. Therefore, the transmitting module 202 and the ring 201 remain stationary.

[0075] When the wind blows and causes the outer membrane 101 to vibrate, it may block the reflection of the infrared beam, and the leaked methane is easily diluted by the wind and difficult to detect. When there is a difference between the first frequency of the infrared beam emitted by the transmitting module 202 and the second frequency of the infrared beam received by the receiving module 203, it indicates that the outer membrane 101 is vibrating and blocking the reflection of the infrared beam. The first adjustment unit adjusts the orientation of the transmitting module 202 to reduce the radial thickness of the detection area, so that the inner side of the detection area is away from the outer surface of the outer membrane 101, thereby avoiding the influence of the vibration of the outer membrane 101 on the reflection of the infrared beam. At the same time, it increases the number of reflections of the infrared beam, thereby enabling the detection of diluted methane.

[0076] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A non-contact detection device for methane gas leakage, characterized in that, The device includes a ring body and a lifting unit located outside the gas storage tank. The gas storage tank has a spherical outer membrane. The axis of the ring body coincides with the vertical axis of the outer membrane. The ring body is equipped with a transmitting module and a receiving module. The inner wall of the ring body is a reflective surface. The infrared beam generated by the transmitting module is reflected by the inner wall of the ring body and then received by the receiving module to form a ring-shaped detection area between the outer membrane and the ring body. The lifting unit is used to control the lifting and lowering of the ring body, so that the detection area can be raised and lowered to cover the outer surface of the outer membrane. The annular detection area has a radial thickness. The transmitting module has a first adjustment part, which is used to adjust the orientation of the transmitting module to change the radial thickness of the detection area. The receiving module has a second adjustment part, which is used to adjust the orientation of the receiving module. The transmitting module is fixed relative to the ring body. A rotating part is also provided outside the gas storage tank, which is used to control the receiving module to move along the trajectory of the ring body.

2. The non-contact detection device for methane gas leakage according to claim 1, characterized in that, The intersection of the infrared beam and the inner wall of the ring is the reflection point. The ratio of the arc length of the two farthest and adjacent reflection points on the circumference of the ring to the circumference of the inner wall of the ring is k. When k is greater than or equal to a preset value, the rotating part controls the transmitting module to rotate synchronously with the ring. When k is less than the preset value, the rotating part controls the transmitting module to remain stationary with the ring.

3. The non-contact detection device for methane gas leakage according to claim 2, characterized in that, When the launch module rotates synchronously with the ring, it has a first velocity, which is positively correlated with k.

4. The non-contact detection device for methane gas leakage according to claim 2, characterized in that, The transmitting module has an adjustment module for regulating its power, which is positively correlated with the number of reflection points.

5. The non-contact detection device for methane gas leakage according to claim 4, characterized in that, The infrared beam emitted by the transmitting module has a first frequency, and the infrared beam received by the receiving module has a second frequency. When the second frequency differs from the first frequency, the first adjustment unit adjusts the orientation of the transmitting module to reduce the radial thickness of the detection area.

6. The non-contact detection device for methane gas leakage according to claim 5, characterized in that, When the second frequency differs from the first frequency, the rotating part controls the receiving module to move along the trajectory of the ring, and the second adjusting part adjusts the orientation of the receiving module to increase the number of reflection points.

7. The non-contact detection device for methane gas leakage according to claim 1, characterized in that, The heights of the transmitting module and the receiving module differ.

8. The non-contact detection device for methane gas leakage according to claim 1, characterized in that, The lifting unit includes multiple lifting cylinders evenly distributed along the circumference of the ring body, and the ring body is rotatably located at the output end of all the lifting cylinders.

9. A non-contact detection method for methane gas leakage, applied to the non-contact detection equipment for methane gas leakage as described in any one of claims 1 to 8, characterized in that, Includes the following steps: The transmitting and receiving modules are activated. The infrared beam generated by the transmitting module is reflected by the inner wall of the ring and received by the receiving module to form a ring-shaped detection area between the outer membrane and the ring body, so as to detect methane leakage within the detection area. Start the lifting unit, which drives the ring body to rise and fall, so that the detection area rises and falls to cover the outer surface of the outer membrane.

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