Gas detection method and system

Abstract

The invention provides a gas detection method, which is applied to a gas detection system and comprises the following steps: acquiring first gas in an underground space where a gas conveying pipeline is located; detecting the proportion of the first target gas and the proportion of the second target gas in the first gas; and under the condition that the first gas is determined to be abnormal according to the proportion of the first target gas, determining the gas type of the abnormal gas in the first gas according to the proportion of the second target gas. The invention further provides a gas detection system.

Description

Technical Field

[0001] This disclosure relates to the field of gas monitoring technology, and in particular to a gas detection method and system. Background Technology

[0002] Both biogas and natural gas are primarily composed of CH4 (methane). Organic sludge in underground spaces such as gas wells and power wells readily produces biogas through anaerobic bacterial fermentation. Low-concentration biogas generally only requires continuous monitoring and treatment, while higher-concentration biogas can be kept within safe limits for a considerable period after normal venting. Its hazards are much lower than those of natural gas leaks; therefore, the handling measures for the two are not entirely the same.

[0003] However, it is currently impossible to effectively distinguish between biogas and natural gas, which easily leads to a large number of false alarms. Summary of the Invention

[0004] This disclosure provides a gas detection method and system.

[0005] In a first aspect, embodiments of this disclosure provide a gas detection method applied to a gas detection system, comprising:

[0006] Obtain the first gas in the underground space where the gas delivery pipeline is located;

[0007] The proportion of the first target gas and the proportion of the second target gas in the first gas are detected;

[0008] If the first gas is determined to be abnormal based on the proportion of the first target gas, the gas type of the abnormal gas in the first gas is determined based on the proportion of the second target gas.

[0009] Secondly, embodiments of this disclosure provide a gas detection system, which includes:

[0010] The gas pump module is used to obtain the first gas in the underground space where the gas delivery pipeline is located;

[0011] A sensor module is used to detect the proportion of the first target gas and the proportion of the second target gas in the first gas;

[0012] The processing module is used to determine the gas type of the abnormal gas in the first gas based on the proportion of the first target gas, when the first gas is determined to be abnormal based on the proportion of the first target gas.

[0013] The proportion of the first target gas in this embodiment can determine whether the first gas is abnormal. If the first gas is determined to be abnormal, the gas type of the abnormal gas in the first gas can be determined based on the proportion of the second target gas. In the underground space where the gas transmission pipeline is located, biogas and natural gas in the first gas can be effectively distinguished. Attached Figure Description

[0014] In the accompanying drawings of the embodiments disclosed herein:

[0015] Figure 1 A schematic flowchart of a gas detection method provided in an embodiment of this disclosure;

[0016] Figure 2 This is a block diagram of a gas detection system provided in an embodiment of the present disclosure;

[0017] Figure 3 A schematic flowchart illustrating an exemplary gas detection method provided in this disclosure embodiment;

[0018] Figure 4 This is a block diagram of an exemplary gas detection system provided in an embodiment of the present disclosure. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions of this disclosure, the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0020] The present disclosure will be described more fully below with reference to the accompanying drawings; however, the embodiments shown may be embodied in different forms, and the present disclosure should not be construed as limited to the embodiments set forth below. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will enable those skilled in the art to fully understand the scope of the disclosure.

[0021] The accompanying drawings of the embodiments disclosed herein are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the detailed embodiments to explain this disclosure and do not constitute a limitation thereof. The above and other features and advantages will become more apparent to those skilled in the art from the description of the detailed embodiments with reference to the accompanying drawings.

[0022] This disclosure may be described with reference to plan and / or cross-sectional views using the ideal schematic diagrams of this disclosure. Therefore, the example illustrations may be modified according to manufacturing techniques and / or tolerances.

[0023] Where there is no conflict, the various embodiments of this disclosure and the features thereof in the embodiments may be combined with each other.

[0024] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. The term "and / or" as used in this disclosure includes any and all combinations of one or more of the associated enumerated entries. The singular forms "a" and "the" as used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. The terms "comprising," "made of," etc., as used in this disclosure specify the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof.

[0025] Unless otherwise specified, all terms used in this disclosure (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined in this disclosure.

[0026] This disclosure is not limited to the embodiments shown in the accompanying drawings, but includes modifications to the configuration based on the manufacturing process. Therefore, the areas illustrated in the drawings are schematic, and the shapes of the areas shown illustrate specific shapes of the areas of an element, but are not intended to be limiting.

[0027] In some related technologies, gas concentration is typically monitored using sensors such as semiconductor sensors, catalytic combustion sensors, microfluidic infrared sensors, and laser sensors. In underground spaces where gas pipelines are located, laser sensors are primarily used for gas detection. The working principle of this laser sensor is as follows: based on Lambert-Beer's law and the characteristic that wavelength changes with injection current and temperature, the absorption spectrum of gas molecules in the underground space is measured, thereby determining the gas concentration.

[0028] However, in the underground spaces where gas pipelines are located, laser-based methane sensors are primarily used to monitor the target gases (i.e., natural gas and biogas). Since natural gas leaks and biogas accumulations require different handling measures, this single methane concentration detection method is insufficient to effectively distinguish between natural gas and biogas, and therefore cannot provide effective guidance for emergency response measures in these two situations. Therefore, a gas detection solution capable of accurately distinguishing between natural gas and biogas is urgently needed.

[0029] like Figure 1 As shown, in a first aspect, embodiments of this disclosure provide a gas detection method applied to a gas detection system, comprising:

[0030] S1. Obtain the first gas in the underground space where the gas delivery pipeline is located;

[0031] S2. Detect the proportion of the first target gas and the proportion of the second target gas in the first gas;

[0032] S3. If the first gas is determined to be abnormal based on the proportion of the first target gas, the gas type of the abnormal gas in the first gas is determined based on the proportion of the second target gas.

[0033] Gas pipelines can be used to transport various types of gases, such as natural gas and liquefied petroleum gas. The underground space where the gas pipeline is located refers to the underground area where the pipeline is buried, used to protect the gas pipeline from the influence of the external environment. Acquiring and detecting a first gas in the underground space can effectively determine whether there is an abnormal gas in that first gas. This disclosure does not impose special limitations on the abnormal first gas; it can refer to the presence of the gas transported by the gas pipeline in the first gas in the underground space, such as a natural gas leak, or it can refer to the presence of a gas that poses a threat to the safety of the gas pipeline in the first gas in the underground space, such as a methane accumulation. In some embodiments, if the proportion of a first target gas in the first gas exceeds a preset proportion, the first gas is determined to be abnormal.

[0034] In some embodiments, the first target gas refers to the gas with the highest proportion in the first gas, and the second target gas refers to the gas with a relatively low proportion in the first gas. The proportion of the first target gas in this embodiment can be used to determine whether the first gas is abnormal. If an abnormality is determined in the first gas, the type of abnormal gas in the first gas can be determined based on the proportion of the second target gas. In the underground space where the gas pipeline is located, since methane is the most abundant gas in both biogas and natural gas, it is possible to effectively distinguish between biogas and natural gas in the first gas based on the second target gas when an abnormality is determined in the first gas.

[0035] In some embodiments, the first target gas is methane; the second target gas includes at least one of the following: carbon dioxide, ethane, and propane.

[0036] In the embodiments of this disclosure, the first target gas is methane, and the second target gas is the other components of the first gas besides methane, which can be used to distinguish between biogas and natural gas, whose main components are both methane.

[0037] Regarding the composition of natural gas and biogas:

[0038] Natural gas is mainly composed of methane, ethane, propane, nitrogen, and butane. Methane accounts for approximately 85%, ethane for approximately 9%, propane for approximately 3%, nitrogen for approximately 2%, and butane for approximately 1%.

[0039] Biogas is mainly composed of methane, carbon dioxide, nitrogen, hydrogen, oxygen, and hydrogen sulfide. The proportion of methane ranges from 50% to 80%, carbon dioxide from 20% to 40%, nitrogen from 0% to 5%, hydrogen from 0% to 1%, oxygen from 0% to 0.4%, and hydrogen sulfide from 0.1% to 3%.

[0040] The composition of natural gas and biogas reveals that methane is the primary component of both. Therefore, detecting the first target gas in the first gas can determine whether there is a natural gas leak or biogas accumulation (i.e., whether the first gas is abnormal). Further detection of the proportions of gases other than methane in natural gas and biogas can identify the type of abnormal gas in the first gas. In some embodiments, since both natural gas and biogas contain nitrogen, and the proportions of nitrogen in both are the same or similar, selecting nitrogen as the second target gas is still insufficient to distinguish between natural gas and biogas. Furthermore, because the proportions of butane in natural gas and hydrogen, oxygen, or hydrogen sulfide in biogas are relatively low (approximately 1%, or less than or equal to 1%), selecting butane, hydrogen, oxygen, or hydrogen sulfide as the second target gas requires high detection accuracy; otherwise, a high false alarm rate may occur. Ethane and propane are gaseous components that are present in higher proportions in natural gas but less present or absent in biogas. Carbon dioxide is another component that is present in higher proportions in biogas but less present or absent in natural gas. Therefore, detecting carbon dioxide, ethane, and propane in the first gas can accurately determine whether the abnormal gas in the first gas is natural gas or biogas when an anomaly is found. Moreover, the detection accuracy of the detection equipment (such as sensors) is lower than that for detecting butane, hydrogen, oxygen, or hydrogen sulfide.

[0041] In some embodiments, step S1 includes:

[0042] When the gas detection system is in normal condition, the first gas in the underground space where the gas delivery pipeline is located is obtained.

[0043] The underground space where the gas transmission pipeline is located has the following environmental characteristics: the underground space contains organic sludge, which is prone to producing biogas due to anaerobic bacterial fermentation; it is difficult to connect to the power supply system provided by the city, and it is difficult to supply power through solar energy; it is difficult to implement wired communication cabling; and the equipment storage environment is harsh.

[0044] The gas detection system used to detect the first gas in the underground space where the gas pipeline is located should be deployed within that underground space and be adaptable to its environment. Therefore, the gas detection system should be able to distinguish abnormal gases (methane, natural gas) in the first gas, and should be battery-powered, have low power consumption, wireless communication capabilities, and be waterproof, explosion-proof, corrosion-resistant, and theft-proof. In some embodiments, the gas detection system may employ low-power wireless communication methods such as NB-IoT (Narrowband Internet of Things) or LoRA (Long Range Low Power Wireless Local Area Network).

[0045] This disclosure does not impose special restrictions on the determination of whether the gas detection system is in a normal state. Instead, it can be determined whether the system has gas detection capability, whether it is powered, whether it can communicate, whether it is submerged in water, or whether it is corroded.

[0046] As one embodiment of this disclosure, a water immersion sensor in the gas detection system determines whether the system is flooded. In the event of flooding, flooding information is reported to the management system's server via wireless communication; in the event of no flooding, a first gas in the underground space is acquired. In some embodiments, the first gas is periodically extracted from the underground space using a gas pump module.

[0047] In some embodiments, step S3 includes:

[0048] If the second target gas is carbon dioxide and the proportion of the second target gas is greater than or equal to the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

[0049] If the second target gas is carbon dioxide and the proportion of the second target gas is less than the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

[0050] In the case where the second target gas is carbon dioxide, since carbon dioxide is a component with a high proportion in biogas and a low proportion or absence in natural gas, the proportion of carbon dioxide is compared with a first preset proportion. Therefore, if the first gas is abnormal due to a high proportion of methane, the type of the abnormal gas can be determined based on the proportion of carbon dioxide. If the proportion of carbon dioxide is higher than or equal to the first preset proportion, the abnormal gas type is determined to be biogas; if the proportion of carbon dioxide is lower than the first preset proportion, the abnormal gas type is determined to be natural gas.

[0051] This disclosure does not impose any special restrictions on the first preset percentage. Since natural gas does not contain carbon dioxide or the proportion of carbon dioxide is extremely low, while the proportion of carbon dioxide in biogas ranges from 20% to 40%, in some embodiments, the first preset percentage is set to 20%.

[0052] In some embodiments, the proportion of carbon dioxide in the first gas is detected by a carbon dioxide sensor.

[0053] As one embodiment of this disclosure, if the proportion of methane in the first gas is greater than or equal to 50%, the proportion of carbon dioxide is compared with 20%. If the proportion of carbon dioxide is greater than or equal to 20%, the abnormal gas type of the first gas is determined to be biogas, indicating that biogas accumulation has occurred in the underground space where the first gas is located. Conversely, if the gas transmission pipeline is a natural gas pipeline, it can be determined that a natural gas leak has occurred in the underground space where the first gas is located.

[0054] In some embodiments, step S3 includes:

[0055] If the second target gas is ethane and / or propane, and the proportion of the second target gas is greater than or equal to the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

[0056] If the second target gas is ethane and / or propane, and the proportion of the second target gas is less than the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

[0057] In cases where the second target gas is ethane and / or propane, since ethane and propane are relatively abundant in natural gas and relatively scarce or absent in biogas, the proportion of ethane and / or propane is compared with a second preset proportion. Therefore, if a high proportion of methane in the first gas causes an anomaly, the gas type of the abnormal gas can be determined based on the proportion of ethane and / or propane. If the proportion of ethane and / or propane is higher than or equal to the second preset proportion, the gas type of the abnormal gas is determined to be natural gas; if the proportion of ethane and / or propane is lower than the second preset proportion, the gas type of the abnormal gas is determined to be biogas.

[0058] This disclosure does not impose any special restrictions on the second preset percentage. Since biogas does not contain ethane and / or propane, or the proportion of ethane and / or propane is extremely low, while the proportion of ethane in natural gas is approximately 9% and the proportion of propane is approximately 3%, in some embodiments, the proportion of ethane is compared with the second preset percentage, which is set to 9%; or, the proportion of propane is compared with the second preset percentage, which is set to 3%; or, the sum of the proportions of ethane and propane is compared with the second preset percentage, which is set to 12%.

[0059] In some embodiments, the proportion of ethane in the first gas is detected by an ethane sensor, and the proportion of propane in the first gas is detected by a propane sensor.

[0060] As one embodiment of this disclosure, if the proportion of methane in the first gas is greater than or equal to 50%, the proportion of ethane is compared with 9%. If the proportion of ethane is greater than or equal to 9%, the abnormal gas type of the first gas is determined to be natural gas. If the gas transmission pipeline is a natural gas pipeline, it can be determined that a natural gas leak has occurred in the underground space where the first gas is located. Conversely, it can be determined that a methane accumulation has occurred in the underground space where the first gas is located.

[0061] In another embodiment of this disclosure, if the proportion of methane in the first gas is greater than or equal to 50%, the proportion of propane is compared with 3%. If the proportion of propane is greater than or equal to 3%, the abnormal gas type of the first gas is determined to be natural gas. If the gas transmission pipeline is a natural gas pipeline, it can be determined that a natural gas leak has occurred in the underground space where the first gas is located. Conversely, it can be determined that a methane accumulation has occurred in the underground space where the first gas is located.

[0062] In some embodiments, after step S3, the method further includes:

[0063] An alarm is triggered based on the type of abnormal gas in the first gas.

[0064] If the proportion of methane in the first gas is higher than the preset proportion, it indicates that the first gas is abnormal and appropriate measures need to be taken in time. Since the measures for handling biogas accumulation and natural gas leakage are different, after determining the gas type of the abnormal gas in the first gas based on the second target gas, an alarm is issued for the gas type of the abnormal gas, so that appropriate measures can be taken in time for the underground space where the first gas is located, thereby improving the efficiency of emergency response.

[0065] The proportion of the first target gas in this embodiment can determine whether the first gas is abnormal. If the first gas is determined to be abnormal, the gas type of the abnormal gas in the first gas can be determined based on the proportion of the second target gas. When the gas transmission pipeline is a natural gas pipeline, it can effectively distinguish whether the abnormal first gas in the underground space where the gas transmission pipeline is located is biogas or natural gas, thereby reducing false alarms in the underground space.

[0066] like Figure 2 As shown, in a second aspect, embodiments of this disclosure provide a gas detection system 200, which includes:

[0067] Air pump module 201 is used to obtain the first gas in the underground space where the gas delivery pipeline is located;

[0068] Sensor module 202 is used to detect the proportion of the first target gas and the proportion of the second target gas in the first gas;

[0069] The processing module 203 is used to determine the gas type of the abnormal gas in the first gas based on the proportion of the second target gas when the first gas is determined to be abnormal based on the proportion of the first target gas.

[0070] The sensor module 202 can be used to detect the proportions of the first target gas and the second target gas in the first gas, respectively. The processing module 203 determines whether the first gas is abnormal based on the proportion of the first target gas. If the first gas is determined to be abnormal, the processing module 203 can determine the type of abnormal gas in the first gas based on the proportion of the second target gas, thereby effectively distinguishing whether the abnormal first gas in the underground space where the gas pipeline is located is biogas or natural gas.

[0071] In some embodiments, the gas detection system 200 is housed within an explosion-proof, waterproof, and corrosion-resistant metal casing to address the complex environment of underground spaces where gas pipelines are located. The system performs gas detection periodically and remains in a dormant state when not detecting gas to reduce power consumption, thus mitigating the challenges of connecting to urban power grids and environments where solar power is unavailable.

[0072] Since the gas detection system 200 is typically deployed in unattended or difficult-to-monitor areas, in some embodiments, the gas detection system 200 may also include an accelerometer and a GPS (Global Positioning System) module to prevent loss. When the gas detection system 200 is lost, if the acceleration detection value of the accelerometer installed in the system is greater than or equal to a preset acceleration threshold, the device containing the system will be activated. The GPS module will then upload the system's location information to the server via the communication module. This allows the server to obtain a loss alarm for the device containing the system and plot the loss trajectory, effectively aiding in retrieval.

[0073] In underground environments, there may be brief periods of poor network signal. During these times, the device's storage module can temporarily store various monitoring information and transmit the data back once the network is restored, ensuring that the monitoring information is not lost.

[0074] In some embodiments, the sensor module 202 is a composite sensor mounted on the system.

[0075] In some embodiments, the sensor module 202 includes a first sensor unit and a second sensor unit;

[0076] The first sensor unit is used to detect the proportion of the first target gas in the first gas, and the second sensor unit is used to detect the proportion of the first target gas in the second gas; wherein, the first target gas is methane, and the second target gas includes at least one of the following: carbon dioxide, ethane, and propane.

[0077] In some embodiments, the first sensor unit may be a methane laser sensor, and the second sensor unit may be one or more of a carbon dioxide sensor, an ethane sensor, and a propane sensor.

[0078] In some embodiments, the processing module 203 is used to:

[0079] If the second target gas is carbon dioxide and the proportion of the second target gas is greater than or equal to the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

[0080] If the second target gas is carbon dioxide and the proportion of the second target gas is less than the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

[0081] In some embodiments, the processing module 203 is used to:

[0082] If the second target gas is ethane and / or propane, and the proportion of the second target gas is greater than or equal to the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

[0083] If the second target gas is ethane and / or propane, and the proportion of the second target gas is less than the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

[0084] This embodiment of the invention can determine whether the first gas is abnormal by measuring the proportion of the first target gas. If the first gas is determined to be abnormal, the type of abnormal gas in the first gas can be determined based on the proportion of the second target gas. When the gas transmission pipeline is a natural gas pipeline, it can effectively distinguish whether the abnormal first gas in the underground space where the gas transmission pipeline is located is biogas or natural gas, thereby reducing false alarms in the underground space.

[0085] To enable those skilled in the art to more clearly understand the technical solutions provided by the embodiments of this disclosure, the technical solutions provided by the embodiments of this disclosure will be described in detail below through specific embodiments:

[0086] Example 1:

[0087] like Figure 3 As shown, exemplarily, as a specific form of an embodiment of this disclosure, when the gas transmission pipeline is a natural gas pipeline, a device equipped with a gas detection system is used to detect and alert whether there is a natural gas leak or methane accumulation in the underground space where the natural gas transmission pipeline is located:

[0088] Step 301: When the sampling period set by the sampling period timer expires, start gas detection.

[0089] Step 302: Determine whether the gas detection device is flooded using the water immersion sensor. If it is flooded, it indicates that the device is not in normal working order, proceed to step 303. If it is not flooded, it indicates that the device is in normal working order, proceed to step 304.

[0090] Step 303: The information that the current device is flooded is reported to the server through the communication module. The server is used to manage the device.

[0091] Step 304: Turn on the air pump to draw in the first gas from the underground space.

[0092] Step 305: Detect the proportion of methane in the first gas using a methane laser sensor and the proportion of carbon dioxide in the first gas using a carbon dioxide sensor.

[0093] Step 306: Determine whether the proportion of methane in the first gas exceeds 50%. If yes, it means that the methane content in the current underground space exceeds the standard, and proceed to step 309; if no, it means that the methane content in the current underground space does not exceed the standard, and proceed to step 307.

[0094] Step 307: Determine that there is no need to trigger an alarm for the first gas at present.

[0095] Step 308: Since there may be temporary network signal difficulties in the underground space, the collected information is stored in the storage module equipped in the device to temporarily store various detection information. After the network is restored or according to the reporting cycle, the information is sent back to the server to ensure that the detection information is not lost.

[0096] Step 309: If the methane content exceeds the standard, determine that the first gas is an abnormal gas and determine whether the proportion of carbon dioxide in the first gas exceeds 20%. If yes, it means that the proportion of carbon dioxide in the current underground space exceeds the standard, and proceed to step 3010; if no, it means that the proportion of carbon dioxide in the current underground space does not exceed the standard, and proceed to step 3011.

[0097] Step 3010: If the gas type of the abnormal gas in the current first gas is determined to be biogas, then a biogas accumulation alarm is triggered.

[0098] Step 3011: If the gas type of the abnormal gas in the current first gas is determined to be natural gas, then a natural gas leak alarm is triggered.

[0099] Step 3012: The information of biogas accumulation alarm or natural gas leak alarm is reported to the server through the communication module.

[0100] Step 3013: End the gas detection of the device in this cycle and enter sleep mode.

[0101] This example demonstrates how methane laser sensors and carbon dioxide sensors can effectively distinguish between natural gas and biogas as the primary gas in underground spaces, allowing for a more accurate determination of whether to address biogas accumulation or natural gas leakage. The gas detection system, installed in underground spaces, is encased in an explosion-proof, waterproof, and corrosion-resistant shell, enabling it to adapt to various complex underground environments. Before collecting the primary gas, a water immersion sensor detects whether the environment is flooded. If not flooded, the gas valve opens, and the gas pump draws in the primary gas for detection, improving the reliability of the equipment. Furthermore, the equipment operates in a low-power state, utilizing batteries for extended periods, reducing maintenance costs. During non-detection periods, a long-term sleep mode is employed to minimize power consumption.

[0102] Example 2:

[0103] like Figure 4 As shown, exemplarily, as a specific form of this disclosure embodiment, when the gas transmission pipeline is a natural gas pipeline, a device equipped with a gas detection system is used to detect and alarm for natural gas leaks or methane accumulation in the underground space where the natural gas transmission pipeline is located. The gas detection system is housed inside an explosion-proof, waterproof, and corrosion-resistant metal casing, and includes:

[0104] The microcontroller 400 is an STM32L431 microcontroller with an ARM Cortex-M4 core and an 80MHz clock speed. Microcontroller 400 compares the methane percentage detected by the methane laser sensor 401 with 50%. If the methane percentage is greater than or equal to 50%, the first gas is determined to be an abnormal gas. Similarly, it compares the carbon dioxide percentage detected by the carbon dioxide sensor 402 with 20%. If the carbon dioxide percentage is greater than or equal to 20%, the abnormal gas type is determined to be biogas; if the carbon dioxide percentage is less than 20%, the abnormal gas type is determined to be natural gas.

[0105] The methane laser sensor 401 uses a Gasboard-2501 sensor, which can detect the concentration (i.e., percentage) of methane in a gas in real time based on tunable laser absorption spectroscopy technology. The methane laser sensor 401 is connected to the microcontroller 400 via a UART 1 (Universal Asynchronous Receiver / Transmitter) port.

[0106] The carbon dioxide sensor 402 uses a CM117 sensor, which detects the concentration of carbon dioxide in the gas in real time based on the principle of non-dispersive infrared absorption. The carbon dioxide sensor 402 is connected to the microcontroller 400 via UART 2 port.

[0107] The accelerometer 403 uses a LIS2DH12TR sensor, which is an ultra-low power sensor that can report the XYZ three-axis acceleration values ​​of the current device in real time. The accelerometer 403 is connected to the microcontroller 400 via a GPIO (General Purpose Input Output) port.

[0108] The water immersion sensor 404 is connected to the microcontroller 400 via a GPIO port.

[0109] Temperature sensor 405 uses a PT100 platinum resistance thermometer. The resistance value of this sensor changes with the ambient temperature, enabling the detection of the ambient temperature and thus providing temperature compensation for the methane laser sensor 401. Temperature sensor 405 is connected to microcontroller 400 via an IIC (Integrated Circuit) port.

[0110] The GPS module 406 is an SKG09BL module that communicates via serial port and has an adjustable baud rate. The GPS module 406 connects to the microcontroller 400 via UART3 port.

[0111] The wireless communication module 407 uses the M5311 NB module, which supports communication protocols such as LwM2M / MQTTP / HTTP / TCP / UDP / COAP. The wireless communication module 407 connects to the microcontroller 400 via SPI (Serial Peripheral Interface) port A.

[0112] The air pump module 408 is a D08L1 module, which is connected to the microcontroller 400 via a GPIO port.

[0113] Storage module 409 uses a W25Q128FW FLASH (flash memory) chip, which communicates via an SPI interface. This FLASH chip has a storage capacity of 128 megabytes. Storage module 409 connects to microcontroller 400 via SPI port B.

[0114] The power module 4010 includes a battery for supplying power to the microcontroller 400, methane laser sensor 401, carbon dioxide sensor 402, accelerometer 403, water immersion sensor 404, temperature sensor 405, GPS module 406, wireless communication module 407, air pump module 408, and storage module 409.

[0115] By detecting the proportion of methane using the methane laser sensor 401, it is possible to determine whether there is any abnormality in the first gas. If it is determined that there is an abnormality in the first gas, the type of abnormal gas in the first gas can be determined by detecting the proportion of carbon dioxide using the carbon dioxide sensor 402. In the underground space where the natural gas pipeline is located, it is possible to effectively distinguish between biogas and natural gas in the first gas.

[0116] Among them, the processor is a device with data processing capabilities, including but not limited to the central processing unit (CPU); the memory is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read-write interface) is connected between the processor and the memory, enabling information exchange between the memory and the processor, including but not limited to the data bus (Bus).

[0117] Those skilled in the art will understand that all or some of the steps, systems, and devices disclosed above, as functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0118] In hardware implementations, the division between functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be executed by several physical components working together.

[0119] Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit (CPU), digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technique for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory (FLASH) or other disk storage; read-only optical disc (CD-ROM), digital versatile disc (DVD) or other optical disc storage; magnetic cartridges, magnetic tapes, disk storage or other magnetic storage; and any other media that can be used to store desired information and can be accessed by a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0120] This disclosure has disclosed exemplary embodiments, and although specific terminology has been used, it is for general illustrative purposes only and should not be construed as limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure as set forth by the appended claims.

Claims

1. A gas detection method, applied to a gas detection system, comprising: Obtain the first gas in the underground space where the gas delivery pipeline is located; The proportion of the first target gas and the proportion of the second target gas in the first gas are detected; If the first gas is determined to be abnormal based on the proportion of the first target gas, the gas type of the abnormal gas in the first gas is determined based on the proportion of the second target gas.

2. The method according to claim 1, wherein, The acquisition of the first gas in the underground space where the gas delivery pipeline is located includes: When the gas detection system is in normal condition, the first gas in the underground space where the gas delivery pipeline is located is obtained.

3. The method according to claim 1, wherein, The first target gas is methane; the second target gas includes at least one of the following: carbon dioxide, ethane, and propane.

4. The method according to claim 3, wherein, The step of determining the type of abnormal gas in the first gas based on the proportion of the second target gas includes: If the second target gas is carbon dioxide and the proportion of the second target gas is greater than or equal to the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas. If the second target gas is carbon dioxide and the proportion of the second target gas is less than the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

5. The method according to claim 3, wherein, The step of determining the type of abnormal gas in the first gas based on the proportion of the second target gas includes: If the second target gas is ethane and / or propane, and the proportion of the second target gas is greater than or equal to the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas. If the second target gas is ethane and / or propane, and the proportion of the second target gas is less than the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

6. The method according to claim 1, wherein, After determining the type of abnormal gas in the first gas based on the proportion of the second target gas, the method further includes: An alarm is triggered based on the type of abnormal gas in the first gas.

7. A gas detection system, comprising: The gas pump module is used to obtain the first gas in the underground space where the gas delivery pipeline is located; A sensor module is used to detect the proportion of the first target gas and the proportion of the second target gas in the first gas; The processing module is used to determine the gas type of the abnormal gas in the first gas based on the proportion of the first target gas, when the first gas is determined to be abnormal based on the proportion of the first target gas.

8. The system according to claim 7, wherein, The sensor module includes a first sensor unit and a second sensor unit; The first sensor unit is used to detect the proportion of the first target gas in the first gas, and the second sensor unit is used to detect the proportion of the first target gas in the second gas; wherein, the first target gas is methane, and the second target gas includes at least one of the following: carbon dioxide, ethane, and propane.

9. The system according to claim 8, wherein, The processing module is used for: If the second target gas is carbon dioxide and the proportion of the second target gas is greater than or equal to the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas. If the second target gas is carbon dioxide and the proportion of the second target gas is less than the first preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas.

10. The system according to claim 8, wherein, The processing module is used for: If the second target gas is ethane and / or propane, and the proportion of the second target gas is greater than or equal to the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be natural gas. If the second target gas is ethane and / or propane, and the proportion of the second target gas is less than the second preset proportion, the gas type of the abnormal gas in the first gas is determined to be biogas.

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