Method for detecting multi-gas concentration in exhaust gas and gas filtering system

Abstract

The invention provides a method for detecting multi-gas concentration in exhaust gas and a gas filtering system, and relates to the technical field of gas detection. The method comprises the following steps: setting components and concentration of mixed gas according to characteristics of target detection gas, and injecting the mixed gas into a light filtering channel to eliminate illumination interference of a red light wave band so as to obtain first illumination; after a user detection instruction is obtained, the gas inlet valve is opened, the exhaust gas enters the detection chamber, the exhaust gas entering the detection chamber is detected through the gas automatic identification module, and the concentration of multiple target detection gases is estimated. Determining the target detection gas with the highest concentration, adjusting an optical filter to filter the first illumination to obtain second illumination, enabling the second illumination to penetrate through the exhaust gas to obtain third illumination, determining the concentration of the target detection gas according to the third illumination and the second illumination, and displaying the concentration on a screen in real time. In a complex gas emission environment, the influence of interference gas is eliminated, and the concentration of target detection gas is accurately detected.

Description

Technical Field

[0001] The present application relates to the field of gas detection technology, and in particular to a method for detecting multiple gas concentrations in exhaust gas and a gas filtering system. Background Art

[0002] Under the dual carbon goals, all environmental protection fields generally need to monitor related emission gases. Among them, the sewage treatment process is actually a carbon emission process. The carbon emissions of the sewage treatment industry account for about 1% of the total social emissions, the largest proportion in the environmental protection industry. Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are emitted during the sewage treatment process. Among them, carbon dioxide mainly comes from the energy consumption process of sewage treatment facilities, while carbon dioxide produced by the degradation of water pollutants is identified as biogenic carbon emissions; methane mainly comes from the anaerobic links of sewage treatment, including pipe networks, anaerobic tanks, septic tanks, sludge anaerobic digesters, etc.; nitrous oxide mainly comes from the nitrification and denitrification stages of the sewage treatment process.

[0003] In the prior art, NDIR infrared gas sensors are generally used to measure the target gas concentration in exhaust gas.

[0004] However, conventional NDIR infrared gas sensors are interfered by CO2. Unfiltered exhaust gas enters the sensor detection area, where high concentrations of CO2 absorb a large amount of infrared light in its absorption band. These absorption bands may overlap with some absorption bands of N2O and CH4, thus interfering with the measurement. Therefore, existing technologies are usually unable to accurately measure N2O and CH4. Summary of the invention

[0005] The present application provides a method for detecting multiple gas concentrations in exhaust gas and a gas filtering system, which are used to solve the problem of low detection accuracy caused by the influence of interfering gases in exhaust gas detection in the prior art, and realize accurate detection of target detection gas concentration in a complex exhaust gas environment.

[0006] In a first aspect, the present application provides a method for detecting the concentration of multiple gases in an exhaust gas, which is applied to a gas filtering system. The method comprises: determining the composition and concentration of a set mixed gas according to the characteristics of the interfering gas to be eliminated and the detection requirements of the target detection gas, wherein the set mixed gas is used to absorb the light interference intensity of the red light band of the interfering gas to be eliminated in the target detection gas; controlling the injection of the set mixed gas into a filtering channel, controlling a light source emitter to emit red light to the filtering channel, and obtaining a first light after eliminating the light interference intensity; and after receiving a target gas detection instruction sent from a user end, controlling the opening of an air intake valve to allow the air to pass through the filter channel. The exhaust gas enters the detection chamber; the gas automatic identification module is controlled to identify the exhaust gas entering the detection chamber, and the gas automatic identification module is used to detect gas characteristics and estimate the target gas concentration of multiple target detection gases at present; after determining the target detection gas with the highest target gas concentration, the filter is adjusted to filter the first light to obtain the second light corresponding to the target detection gas; the second light is controlled to pass through the exhaust gas to obtain the third light; the gas concentration of the target detection gas is determined by the gas sensor according to the third light and the second light, and the gas concentration is transmitted to the display screen in real time for dynamic display.

[0007] By adopting the above technical solution, the mixed gas is set according to the characteristics of the interfering gas to be eliminated and the requirements of the target detection gas, injected into the filter channel and emitted red light to obtain the first illumination, and a series of subsequent operations can eliminate the interference of the interfering gas illumination, accurately identify the target detection gas, adjust the filter to obtain accurate illumination, and finally determine the gas concentration and display it. Each step is closely coordinated to achieve high-precision detection of the target detection gas concentration in a complex exhaust gas environment, and improve the detection accuracy.

[0008] In combination with some embodiments of the first aspect, in some embodiments, after receiving the target gas detection instruction sent by the user end, after the step of controlling the opening of the air intake valve to allow the exhaust gas to enter the detection chamber, it also includes: preprocessing the measurement environment in the detection chamber according to the standard measurement environment of the target detection gas, and the preprocessing includes adjusting the measurement temperature of the measurement environment to the standard detection temperature range through the gas temperature adjustment unit in the detection chamber, and adjusting the measurement pressure of the measurement environment to the standard pressure range through a pre-set air pressure stabilizer.

[0009] By adopting the above technical solution, the exhaust gas is in an ideal measurement environment when entering the detection room, which is consistent with the standard measurement environment, avoiding the influence of environmental factors on the gas detection results and ensuring the accuracy and reliability of the detection data.

[0010] In combination with some embodiments of the first aspect, in some embodiments, after controlling the injection of the set mixed gas into the filter channel, controlling the light source emitter to emit red light to the filter channel, and obtaining the first light after eliminating the light interference intensity, it also includes: obtaining the current mixed gas concentration through the gas concentration sensor inside the filter channel; comparing and judging the current mixed gas concentration with the set mixed gas concentration threshold; if the current mixed gas concentration is lower than the set mixed gas concentration threshold, sending a start signal to the gas replenishment device, so that the gas replenishment device starts to deliver the mixed gas according to the preset replenishment flow strategy.

[0011] By adopting the above technical solution, the concentration of the mixed gas can be monitored in real time, and the deficiency can be replenished in time to ensure that the mixed gas is always at an appropriate concentration, thereby continuously and stably eliminating the interference of interfering gas light, maintaining the efficient operation of the detection system, and ensuring that the accuracy of target gas detection is not affected by fluctuations in the concentration of the mixed gas.

[0012] In combination with some embodiments of the first aspect, in some embodiments, if the current mixed gas concentration is lower than the set mixed gas concentration threshold, then after the step of sending an open signal to the gas replenishing device so that the gas replenishing device starts to deliver the mixed gas according to a preset replenishing flow strategy, the method also includes: if it is detected that the current mixed gas concentration is greater than the set mixed gas concentration threshold, then closing the delivery valve of the gas replenishing device.

[0013] By adopting the above technical solution, in synergy with the previous step of supplementing the mixed gas, the concentration of the mixed gas can be accurately controlled within an appropriate range, avoiding waste of resources or adverse effects on the detection system caused by excessive concentration, while preventing excessive supplementation from affecting detection accuracy, further optimizing the mixed gas management.

[0014] In combination with some embodiments of the first aspect, in some embodiments, after receiving the target gas detection instruction sent by the user end, after the step of controlling the opening of the air intake valve to allow the exhaust gas to enter the detection chamber, it also includes: obtaining the current pressure value of the exhaust gas through the pressure sensor in the detection chamber; if the pressure value exceeds the alarm threshold, an overpressure reminder is issued to the display.

[0015] By adopting the above technical solution, the gas pressure can be monitored in real time, and timely feedback can be given when the pressure is abnormal, so as to prevent excessive pressure from damaging the detection equipment and ensure the safe operation of the detection equipment. At the same time, it can remind operators to deal with abnormal situations in time, maintain the stability and reliability of the detection system, ensure the smooth progress of the detection work, and reduce equipment failures and detection interruptions caused by pressure problems.

[0016] In combination with some embodiments of the first aspect, in some embodiments, after the step of determining the gas concentration of the target detection gas according to the third illumination and the second illumination by a gas sensor, and transmitting the gas concentration in real time to a display screen for dynamic display, it also includes: constructing an error correction model according to multiple interfering gas concentrations and measurement error data, and the measurement error data refers to the difference between the measured concentration and the actual concentration of the target detection gas; obtaining the interfering gas concentration through the gas automatic identification module; and calculating and correcting the gas concentration of the target detection gas in real time through the error correction model.

[0017] By adopting the above technical solution and combining various data, the measurement error can be effectively compensated and the detection accuracy can be improved. Especially in the presence of interfering gas, it can more accurately reflect the true concentration of the target detection gas and enhance the credibility of the detection results.

[0018] In combination with some embodiments of the first aspect, in some embodiments, after the step of determining the gas concentration of the target detection gas according to the third light and the second light by a gas sensor, and transmitting the gas concentration in real time to a display screen for dynamic display, it also includes: obtaining identification data of the gas automatic identification module, and when it is identified that the concentration of the first target detection gas is less than a set threshold and the concentration of the second target detection gas is greater than the set threshold, controlling the gas sensor to replace it with a filter that matches the second gas to be detected.

[0019] By adopting the above technical solution, the filter is automatically adjusted according to the actual detection situation to ensure that the sensor always matches the current main target detection gas, improve the detection targeting and accuracy, enable the detection system to quickly adapt to changes in different gas concentrations, timely optimize the detection method, improve detection efficiency and accuracy, and better meet the needs of various gas detection.

[0020] In a second aspect, the present application provides a server, comprising: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to cause the server to execute the method described in the first aspect and any possible implementation of the first aspect.

[0021] In a third aspect, the present application provides a computer-readable storage medium comprising instructions, which, when executed on a server, causes the server to execute the method described in the first aspect and any possible implementation of the first aspect.

[0022] In a fourth aspect, the present application provides a computer program product, which, when executed on a server, enables the server to execute the method described in the first aspect and any possible implementation manner of the first aspect.

[0023] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. Due to the adoption of technical means to determine the setting of mixed gas based on the characteristics of the interfering gas to be eliminated and the requirements of the target detection gas, and to coordinate the illumination processing, gas detection and concentration determination in multiple steps, the technical problems of large influence of interfering gas and low detection accuracy in the detection of exhaust gas in the prior art are effectively solved, thereby achieving the technical effect of high-precision detection of target gas concentration in a complex exhaust gas environment and providing reliable data for gas monitoring.

[0024] 2. Due to the adoption of technical means to monitor the concentration of mixed gas in real time and replenish it as needed after specific light treatment, the technical problem that the existing technology cannot ensure the stability of the concentration of mixed gas, thus affecting the interference elimination effect and detection accuracy, is effectively solved, thereby achieving the technical effect of continuously and stably eliminating interference and ensuring the efficient and accurate operation of the detection system.

[0025] 3. Due to the technical means of building an error correction model and combining the gas automatic identification module to obtain data for concentration correction, the technical problems of large measurement errors and inaccurate detection results caused by interfering gases in the existing technology are effectively solved, thereby achieving the technical effect of improving detection accuracy and enhancing the credibility of detection results to adapt to complex gas environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of an application structure of a method for detecting multiple gas concentrations in exhaust gas in an embodiment of the present application; Figure 2 It is a flow chart of a method for detecting the concentration of multiple gases in exhaust gas in an embodiment of the present application; Figure 3 is another flow chart of a method for detecting multiple gas concentrations in exhaust gas in an embodiment of the present application; Figure 4 It is a schematic diagram of the structure of a physical device of the gas filtering system in the embodiment of the present application. DETAILED DESCRIPTION

[0027] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification and appended claims of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to and includes any or all possible combinations of one or more listed items.

[0028] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0029] The following first describes the structure used in the method provided by this embodiment. Figure 1 , which is a schematic diagram of an application structure of a method for detecting multiple gas concentrations in exhaust gas in an embodiment of the present application.

[0030] exist Figure 1 In the figure, the leftmost side of the gas filter system includes a light source transmitter, which is used to emit red light. The filter channel is filled with a pre-set mixed gas, and the mixed gas absorbs the red light interference of the interfering gas (such as CO2). When the light passes through the mixed gas in the filter channel, the first light after the light interference intensity is eliminated is obtained. The filter is located behind the filter channel. The filter can be adjusted according to the type of target detection gas. The first light passes through the set filter, and the second light is obtained. When the second light passes through the exhaust gas in the detection room, the third light is obtained. The gas sensor determines the gas concentration of the target detection gas by the difference between the second light and the third light. This system eliminates the influence of interfering gases through double filtering (mixed gas filter + filter), especially solves the interference problem of CO2 on the detection of other gases (such as N2O and CH4), and improves the detection accuracy.

[0031] For ease of understanding, the following describes the process of the method provided by this implementation. Figure 2 , is a flow chart of a method for detecting multiple gas concentrations in exhaust gas in an embodiment of the present application.

[0032] S201, according to the characteristics of the interfering gas to be eliminated and the detection requirements of the target detection gas, determine the composition and concentration of the set mixed gas, the set mixed gas is used to absorb the light interference intensity of the red light band of the interfering gas to be eliminated in the target detection gas; The main purpose of this step is to design a specific mixed gas to eliminate the influence of interfering gases (such as CO2) on the concentration measurement of target detection gases (such as CH4, N2O). This is because in infrared spectroscopy analysis, the absorption spectra of different gases may overlap, resulting in measurement errors. For common interfering gases, such as in sewage treatment emission gas detection, CO2 is the main interfering gas. It has a specific absorption spectrum in the infrared band, and its absorption band may partially overlap with the target detection gas (such as N2O and CH4). Through spectral analysis technology, the absorption peak position and absorption intensity characteristics of CO2 in the red light band (such as a specific wavelength range) are accurately determined. This requires the use of a high-precision spectrometer to detect pure CO2 gas samples and obtain its detailed spectral absorption curve.

[0033] Clarify the detection requirements of target gas: Taking N2O and CH4 as examples, according to their standard requirements in environmental monitoring or industrial emission control, determine the required detection accuracy, detection limit (such as the lowest detectable concentration value) and response time (the time requirement from the gas entering the detection system to the accurate concentration result). At the same time, considering the possible concentration range of these gases in actual emissions, determine the appropriate detection range. Based on the above analysis, select a gas that can effectively absorb the interference of CO2 in the red light band as the mixed gas component. For example, a certain rare gas or gas mixture of a specific concentration may be selected, whose molecular structure can produce complementary absorption effects in the interference band of CO2. Determine the optimal proportion of each component through a large number of experiments and theoretical calculations. For example, after many experiments, it was found that when gas A accounts for X% and gas B accounts for Y%, the interference absorption effect of CO2 in a specific red light band is the best, thereby determining the specific composition and concentration of the set mixed gas. In actual operation, a high-precision gas mixing device is used to accurately prepare the mixed gas according to the predetermined ratio. The device has flow control and real-time concentration monitoring functions to ensure the accuracy and stability of the mixed gas.

[0034] In some embodiments, a real-time gas analysis module can be installed in the gas filter system, which can continuously monitor the real-time changes in the concentration of interfering gases (such as CO2) in the exhaust gas. When the concentration of the interfering gas fluctuates greatly (outside the preset range), the composition and concentration of the set mixed gas are automatically adjusted according to the pre-established algorithm model, and the pre-established algorithm model is trained based on a large amount of experimental data and actual emission scenario data. In the model training stage, data on the changes in the concentration of interfering gases in the exhaust gas under different industries and different working conditions and the corresponding optimal mixed gas composition and concentration adjustment strategy are collected. For example, the range of CO2 concentration changes in different treatment stages, different seasons, different influent water quality, etc. of the sewage treatment plant, as well as the mixed gas composition and concentration combination that can effectively eliminate interference are recorded in detail, and the machine learning algorithm is used to analyze and train these data to establish a mathematical relationship model between the concentration of interfering gases and the composition and concentration of the mixed gas. In this way, if the CO2 concentration suddenly increases, the system automatically increases the proportion of gas components with stronger CO2 absorption capacity, and adjusts other components accordingly to ensure that the best interference elimination effect is always maintained. At the same time, the adjustment process is seamlessly connected with the subsequent detection process, without the need for human intervention, and achieves an adaptive response to different emission conditions.

[0035] S202, controlling the injection of the set mixed gas into the filter channel, controlling the light source emitter to emit red light to the filter channel, and obtaining the first illumination after eliminating the illumination interference intensity; In this step, the gas filter system first needs to accurately control the process of setting the mixed gas injection into the filter channel. To achieve this goal, the system is equipped with a high-precision gas injection device, which is connected to the gas source storing the set mixed gas and controlled by the preset program logic to ensure that the mixed gas can enter the filter channel at a stable and uniform flow rate. In actual operation, the system will achieve precise injection by controlling the valve opening degree and injection time of the gas injection device according to the pre-calculated required mixed gas volume. At the same time, in order to ensure that the mixed gas is evenly distributed in the filter channel, a special gas diffusion structure is designed inside the filter channel. This structure consists of a series of carefully arranged guide plates and gas dispersers. When the mixed gas enters the filter channel, it will quickly and evenly fill the entire channel space under the action of these structures, thereby ensuring effective absorption of interference in the red light band. When the set mixed gas is stably distributed in the filter channel, the light source transmitter starts working. The light source transmitter uses a highly stable red light emitting diode (LED) as the light source, and its emission wavelength is precisely set near the red light band absorption peak of the interfering gas to be eliminated (such as CO2) in the target detection gas, usually in a specific nanometer-level wavelength range.

[0036] The red light emitted by the light source emitter interacts with the mixed gas after entering the filter channel. Specific components in the mixed gas selectively absorb the part of the red light band that overlaps with the absorption band of the interfering gas, thereby reducing the light intensity of this band. After being absorbed by the mixed gas, the light output from the other end of the filter channel is the first light after eliminating the light interference intensity.

[0037] S203, after receiving the target gas detection instruction sent by the user end, controlling to open the air inlet valve to allow the exhaust gas to enter the detection chamber; When the user sends a target gas detection command, the control unit of the gas filter system responds quickly. The air intake valve adopts an electric control method, and the system sends a command to drive the valve motor to work, thereby realizing the precise opening of the valve.

[0038] Before opening the air inlet valve, the test chamber is purged with pure inert gas (such as nitrogen) through the gas purge device in the test chamber to remove other gases that may remain in the test chamber to avoid interference with subsequent exhaust gas detection. The purge process lasts for a period of time to ensure that the gas environment in the test chamber reaches the initial clean state. Then, the system starts the gas temperature adjustment unit and the air pressure stabilizer in the test chamber. The gas temperature adjustment unit adopts advanced thermoelectric cooling / heating technology to achieve precise adjustment of the temperature in the test chamber by controlling the current direction and size of the thermoelectric module. When receiving the target gas detection instruction, the system quickly adjusts the temperature in the test chamber to within the standard measurement temperature range of the target detection gas. The air pressure stabilizer monitors the air pressure in the test chamber in real time through the pressure sensor and compares it with the preset standard pressure range. If the air pressure deviates from the standard range, the air pressure stabilizer will automatically start the corresponding adjustment mechanism. After ensuring that the test chamber environment is ready, the system controls the opening of the air inlet valve and the exhaust gas begins to enter the test chamber. The degree of opening of the air inlet valve can be precisely controlled according to the expected flow rate and detection requirements of the exhaust gas. When the exhaust gas enters the detection room, the system continuously monitors the various environmental parameters in the detection room, such as temperature, air pressure, and gas flow rate. If any parameter is found to be abnormal, the system will immediately take corresponding adjustment measures to ensure that the detection environment is always in the best state, providing reliable guarantee for subsequent gas detection.

[0039] In some embodiments, the current exhaust gas pressure value can also be obtained through the pressure sensor in the detection chamber. If the pressure value exceeds the alarm threshold, an overpressure reminder is issued to the display. Such a pressure monitoring and overpressure reminder mechanism effectively prevents damage to the detection equipment caused by excessive pressure, ensures the safe operation of the detection equipment, and ensures the smooth progress of the detection work, reducing equipment failures and detection interruptions caused by pressure problems.

[0040] S204, controlling the gas automatic identification module to identify the exhaust gas entering the detection chamber, the gas automatic identification module is used to detect gas characteristics and estimate the target gas concentration of the current multiple target detection gases; The gas automatic identification module starts working immediately after the exhaust gas enters the detection chamber. The module integrates a variety of advanced gas detection technologies, including but not limited to infrared spectroscopy analysis technology, electrochemical sensor technology, and semiconductor gas sensor technology, to achieve accurate identification and concentration estimation of multiple target detection gases. When the exhaust gas enters the detection chamber, the infrared spectrometer emits infrared light covering the characteristic absorption wavelength range of the target detection gas and detects the change in light intensity after passing through the gas. By comparing the light intensity difference between the incident light and the outgoing light at different wavelengths, the pre-established gas spectrum database is used for matching analysis to determine the type of target detection gas that may exist in the exhaust gas. For example, for carbon dioxide (CO2) detection, it has a strong absorption peak at a specific wavelength (such as 4.26μm). When the infrared spectrometer detects that the light intensity at this wavelength is significantly weakened, it is preliminarily judged that the exhaust gas contains CO2. Then, according to the degree of light intensity weakening, combined with Beer's law, the concentration of CO2 is estimated through a mathematical calculation model. After completing the detection and analysis of the exhaust gas, the gas automatic identification module transmits the detected target detection gas type and its estimated target gas concentration information to the system. These data will serve as an important basis for the subsequent determination of the target detection gas with the highest target gas concentration and for further accurate measurement of gas concentration.

[0041] S205, after determining the target detection gas with the highest target gas concentration, adjusting the filter to filter the first light to obtain a second light corresponding to the target detection gas; After the gas automatic identification module completes the concentration estimation of multiple target detection gases in the exhaust gas, the gas filter system will analyze these data to determine the target detection gas with the highest target gas concentration. Once the target gas is determined, the system will automatically adjust the filter parameters according to the preset correspondence. The adjustment of the filter is achieved through a high-precision motor drive device, which can accurately control the angle and position of the filter to match the absorption spectrum characteristics of the target detection gas. For example, for different target detection gases, such as methane and nitrous oxide, the absorption peak positions in the infrared band are different. The system will adjust the filter to a position that can maximize the transmission of the characteristic wavelength of the target gas based on the pre-stored database information. During the adjustment of the filter, the system will monitor the status of the filter in real time to ensure that it is in place accurately. This is achieved through a position sensor installed near the filter. The position sensor feeds back the actual position information of the filter to the system. The system compares and adjusts according to the preset target position to ensure that the adjustment accuracy of the filter is within a very small error range.

[0042] When the filter is adjusted, the first light passes through the adjusted filter, and the second light that is adapted to the absorption characteristics of the target detection gas is obtained through the selective transmission of the filter. The spectral characteristics of the second light will be more conducive to the subsequent accurate measurement of the concentration of the target detection gas. S206, controlling the second illumination to pass through the exhaust gas to obtain a third illumination; After obtaining the second illumination corresponding to the target detection gas, the gas filter system precisely controls the optical path system to make the second illumination pass vertically through the exhaust gas in the detection chamber. The optical path design inside the detection chamber has been carefully optimized, using high-quality optical lenses and reflectors to ensure that the second illumination can maintain a stable propagation direction and intensity when passing through the exhaust gas, reducing the loss and scattering of light during transmission.

[0043] When light passes through the exhaust gas, the target detection gas molecules in the exhaust gas absorb light of a specific wavelength, causing the intensity and spectral characteristics of the second light to change. After the second light passes through the exhaust gas, the system uses a high-precision light detector to receive the light that passes through the exhaust gas. This light is the third light.

[0044] S207: Determine the gas concentration of the target detection gas according to the third illumination and the second illumination by a gas sensor, and transmit the gas concentration to a display screen in real time for dynamic display.

[0045] After receiving the relevant information of the third illumination and the second illumination (usually in the form of electrical signals), the gas sensor uses advanced signal processing algorithms to analyze these signals. First, the signal is subjected to noise reduction and amplification processing to improve the quality and resolution of the signal. By adopting a high-precision analog-to-digital converter, the analog electrical signal is converted into a digital signal to facilitate subsequent accurate calculations. Then, according to the Lambert-Beer law, the gas sensor calculates the concentration of the target detection gas by comparing the intensity changes of the third illumination and the second illumination. This law describes the quantitative relationship between light absorption and substance concentration. In this system, the accurate concentration of the target detection gas is calculated by combining the pre-calibrated calibration curve and the known optical path length (i.e., the distance that the second illumination passes through the exhaust gas, which has been accurately determined in the system design) with the real-time measured light intensity changes.

[0046] After calculating the target detection gas concentration, the gas sensor transmits the concentration data to the system, and the system further processes and verifies the data to ensure the accuracy and reliability of the data. For example, by comparing with historical data and checking the rationality range of the data, the influence of abnormal data can be eliminated. The verified gas concentration data is transmitted to the display screen in real time for dynamic display. The display screen uses high-resolution liquid crystal display (LCD) or organic light-emitting diode display (OLED) and other technologies to clearly and intuitively display the concentration changes of the target detection gas. The display interface is designed to be concise and clear, and can also display other relevant information, such as measurement time, detection environment parameters, etc., so that users can understand the detection situation at any time. The system also has a data storage function, which stores the concentration data and related measurement parameters of each measurement in the internal memory or external storage device for subsequent data analysis and processing.

[0047] In some embodiments, the gas automatic identification module generates detailed identification data after detecting the exhaust gas entering the detection chamber. These data include characteristic analysis results and estimated concentration values ​​for multiple target detection gases. When it is judged that the concentration of the first target detection gas is less than the set threshold and the concentration of the second target detection gas is greater than the set threshold, it means that the concentration distribution of the gas components in the exhaust gas has changed, and the filter of the gas sensor needs to be adjusted to adapt to the new main target detection gas (i.e., the second target detection gas). The set threshold is pre-set according to the specific detection requirements and the characteristics of the target detection gas. Once it is determined that the filter needs to be replaced, the system will send a control signal to the gas sensor to start the filter replacement program. The gas sensor is equipped with a precision filter switching device, which is usually driven by a motor and can accurately control the position switching of the filter. The system determines the position number or characteristic parameters of the filter that matches the second target detection gas based on the pre-stored database information. Then, a command is sent to the motor of the filter switching device to control the motor to rotate, drive the mechanical structure such as the filter holder or turntable, and replace the current filter with a filter that matches the second target detection gas. When the filter replacement is completed, the gas sensor will use the new filter to detect the exhaust gas. The new filter can better transmit the characteristic wavelength of the second target detection gas, improving the accuracy of its concentration measurement.

[0048] In the embodiments of the present application, by determining and setting the composition and concentration of the mixed gas based on the characteristics of the interfering gas to be eliminated and the requirements of the target detection gas, and combining a series of collaborative operations such as injecting mixed gas to eliminate light interference, accurately controlling the detection environment, and intelligently identifying and adjusting the relevant parameters of the detection gas, high-precision detection and accurate display of the target detection gas concentration in a complex exhaust gas environment are achieved, effectively solving the problem of large influence of interfering gases and low detection accuracy in the prior art.

[0049] In some embodiments, a large amount of experimental data needs to be collected to determine the concentrations of multiple interfering gases and the corresponding measurement error data of the target detection gas. During the experiment, various interfering gases with known concentrations (such as CO2, which is common in sewage treatment emission gas detection) are mixed with target detection gases (such as CH4, N2O, etc.) in different proportions to form a series of standard gas samples. Then, these samples are passed into the gas filter system for detection to obtain the measured concentration of the target detection gas.

[0050] The measurement error (the difference between the measured concentration and the actual concentration) is calculated by comparing the actual concentration of the target detection gas in the standard gas sample. At the same time, the gas automatic identification module is used to accurately obtain the concentration of the interfering gas in the sample. These interfering gas concentration data and the corresponding measurement error data are used as training data, and an appropriate machine learning algorithm is used to build an error correction model. The gas automatic identification module continues to detect the gas after the exhaust gas enters the detection chamber. It uses a variety of integrated advanced gas detection technologies to identify interfering gases and estimate their concentrations. In the actual detection process, when the gas automatic identification module obtains the concentration of interfering gases in the current exhaust gas, these data are input into the constructed error correction model. The model calculates the corresponding measurement error correction value based on the input interfering gas concentration data according to the pre-established mathematical relationship. Then, the correction value is applied to the measured concentration of the target detection gas measured by the gas sensor. The system will update and display the corrected target detection gas concentration in real time to ensure that users can obtain more accurate detection results. At the same time, the system will continue to monitor changes in the concentration of interfering gases and repeat the above process to achieve dynamic correction of the target detection gas concentration to adapt to real-time changes in the exhaust gas composition and concentration, effectively improving the detection accuracy, especially in complex environments with multiple interfering gases. It can more accurately reflect the true concentration of the target detection gas.

[0051] After combining the above content, the following is a more detailed description of the process of the method provided by this implementation. Figure 3 , is another flow chart of the method for detecting multiple gas concentrations in exhaust gas in an embodiment of the present application.

[0052] S301, obtaining the current mixed gas concentration through the gas concentration sensor inside the filter channel; A high-precision gas concentration sensor is installed inside the filter channel of the gas filter system, which can measure the concentration of the mixed gas in the filter channel in real time and accurately. When the system is in operation, the gas concentration sensor continues to work, and its probe part is in full contact with the mixed gas to measure the gas concentration of the mixed gas.

[0053] S302, determining whether the current mixed gas concentration is lower than a set mixed gas concentration threshold; After obtaining the current mixed gas concentration, the gas filter system will compare the concentration value with the preset mixed gas concentration threshold. The mixed gas concentration threshold is set according to the system's requirements for the interference gas elimination effect and experimental verification, ensuring that the mixed gas can effectively absorb the light interference intensity of the interference gas to be eliminated (such as CO2) in the red light band within this concentration range.

[0054] When the current mixed gas concentration is lower than the set mixed gas concentration threshold, the system determines that the mixed gas needs to be supplemented to maintain its effective absorption capacity for the interfering gas, and then executes step S303; If the current mixed gas concentration is equal to or higher than the set threshold, the system considers that the current mixed gas concentration is within a suitable range and no supplementary operation is required, and then executes step S304.

[0055] S303, sending a start signal to the gas replenishment device, so that the gas replenishment device starts to deliver the mixed gas according to a preset replenishment flow strategy; When the gas filter system determines that the current mixed gas concentration is lower than the set threshold, it immediately sends an opening signal to the gas replenishment device. The gas replenishment device is a precision gas delivery system, which is mainly composed of a gas storage source, a pressure regulating device, a flow control valve, a gas delivery pipeline, and related sensors and controllers. The gas storage source is used to store the pre-prepared set mixed gas. The flow control valve is a key component of the gas replenishment device. It is responsible for accurately controlling the delivery flow of the mixed gas. The valve adopts a high-precision electric flow control valve. The preset replenishment flow strategy is based on the system's response requirements to changes in the mixed gas concentration and the performance parameters of the gas replenishment device. For example, the system adopts a proportional integral differential (PID) control algorithm. According to the difference between the current mixed gas concentration and the set threshold, the target opening value of the flow control valve is calculated. During the gas replenishment process, the flow control valve adjusts the opening in real time according to the instructions of the gas filter system, so that the replenishment flow can quickly and accurately increase the mixed gas concentration to an appropriate range. In order to ensure the accuracy of the supplementary flow, the gas replenishment equipment is also equipped with a flow monitoring sensor. The sensor is installed on the gas delivery pipeline, which can monitor the actual gas delivery flow in real time and feed back the flow data to the system in the form of an electrical signal. The system further fine-tunes the flow control valve based on the feedback information to form a closed-loop control system to ensure that the supplementary flow always complies with the preset strategy and achieves precise control of the mixed gas concentration.

[0056] S304, close the delivery valve of the gas replenishing equipment.

[0057] During the process of the gas replenishment device delivering the mixed gas according to the preset strategy, the gas concentration sensor inside the filter channel of the gas filter system continuously monitors the mixed gas concentration. When the system detects that the current mixed gas concentration reaches or exceeds the set mixed gas concentration threshold, it immediately sends a closing signal to the delivery valve of the gas replenishment device. After the valve is closed, the system confirms the mixed gas concentration again through the gas concentration sensor inside the filter channel. If it is detected that the mixed gas concentration is still within the set threshold range and is stable for a period of time (for example, a few minutes), the system determines that the mixed gas replenishment operation has been successfully completed. At this time, the system enters the normal detection standby state, waiting for the next detection instruction or continuing the subsequent detection process (such as the detection operation after the exhaust gas enters the detection chamber).

[0058] By adopting the gas concentration monitoring and supplementary control method in the embodiment of the present application, accurate management of the mixed gas concentration is achieved through real-time monitoring, precise judgment and intelligent supplementary control of the mixed gas concentration in the filter channel, which not only effectively ensures that the mixed gas is always in a suitable concentration range that can effectively eliminate the light interference of the interfering gas, but also greatly improves the stability and reliability of the entire detection system, ensures the accuracy and continuity of the target gas concentration detection in a complex exhaust gas environment, and reduces the detection error caused by fluctuations or insufficient mixed gas concentration.

[0059] The following describes the gas filter system in the embodiment of the present invention from the perspective of hardware processing. Figure 4 , is a schematic diagram of a physical device structure of a gas filtering system in an embodiment of the present application.

[0060] It should be noted that Figure 4 The structure of the gas filter system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0061] like Figure 4 As shown, the gas filter system includes a central processing unit (Central Processing Unit, system) 401, which can perform various appropriate actions and processes according to the program stored in the read-only memory (Read-Only Memory, ROM) 402 or the program loaded from the storage part 408 to the random access memory (Random Access Memory, RAM) 403, such as executing the method described in the above embodiment. In the RAM 403, various programs and data required for the operation of the system are also stored. The system 401, the ROM 402 and the RAM 403 are connected to each other through a bus 404. The input / output (Input / Output, I / O) interface 405 is also connected to the bus 404.

[0062] The following components are connected to the I / O interface 405: an input section 406 including an audio input device, a button switch, etc.; an output section 407 including a liquid crystal display (LCD) and an audio output device, an indicator light, etc.; a storage section 408 including a hard disk, etc.; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as needed. A removable medium 411, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 410 as needed so that a computer program read therefrom is installed into the storage section 408 as needed.

[0063] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication part 409, and / or installed from a removable medium 411. When the computer program is executed by the central processing unit (system) 401, various functions defined in the present invention are performed.

[0064] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, apparatus, or device.

[0065] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings.

[0066] Specifically, the gas filter system of this embodiment includes a processor and a memory. The memory stores a computer program. When the computer program is executed by the processor, the method for detecting the concentration of multiple gases in the exhaust gas provided in the above embodiment is implemented.

[0067] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the gas filter system described in the above embodiment; or may exist independently without being assembled into the gas filter system. The above storage medium carries one or more computer programs, and when the above one or more computer programs are executed by a processor of the gas filter system, the gas filter system implements the method for detecting multiple gas concentrations in exhaust gas provided in the above embodiment.

[0068] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0069] As used in the above embodiments, the term "when..." may be interpreted to mean "if..." or "after..." or "in response to determining..." or "in response to detecting...", depending on the context. Similarly, the phrases "upon determining..." or "if (the stated condition or event) is detected" may be interpreted to mean "if determining..." or "in response to determining..." or "upon detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context.

[0070] Those skilled in the art can understand that to implement all or part of the processes in the above-mentioned embodiments, the processes can be completed by computer programs to instruct related hardware, and the programs can be stored in computer-readable storage media. When the programs are executed, they can include the processes of the above-mentioned method embodiments. The aforementioned storage media include: ROM or random access memory RAM, magnetic disk or optical disk and other media that can store program codes.

Claims

1. A method for detecting the concentration of multiple gases in exhaust gas, applied to a gas filtering system, characterized in that: The method comprises: According to the characteristics of the interfering gas to be eliminated and the detection requirements of the target detection gas, the composition and concentration of the set mixed gas are determined, and the set mixed gas is used to absorb the light interference intensity of the red light band of the interfering gas to be eliminated in the target detection gas; Controlling the injection of the set mixed gas into the filter channel, controlling the light source emitter to emit red light to the filter channel, and obtaining the first illumination after eliminating the illumination interference intensity; After receiving the target gas detection instruction sent by the user end, control to open the air inlet valve to allow the exhaust gas to enter the detection chamber; Controlling the gas automatic identification module to identify the exhaust gas entering the detection chamber, the gas automatic identification module is used to detect gas characteristics and estimate the target gas concentration of the current plurality of target detection gases; After determining the target detection gas with the highest target gas concentration, adjusting the filter to filter the first illumination to obtain a second illumination corresponding to the target detection gas; controlling the second illumination to pass through the exhaust gas to obtain a third illumination; The gas concentration of the target detection gas is determined by a gas sensor according to the third illumination and the second illumination, and the gas concentration is transmitted to a display screen in real time for dynamic display.

2. The method according to claim 1, characterized in that After receiving the target gas detection instruction sent by the user end, the step of controlling the opening of the air intake valve to allow the exhaust gas to enter the detection chamber also includes: The measurement environment in the detection chamber is preprocessed according to the standard measurement environment of the target detection gas. The preprocessing includes adjusting the measurement temperature of the measurement environment to the standard detection temperature range through the gas temperature adjustment unit in the detection chamber, and adjusting the measurement pressure of the measurement environment to the standard pressure range through a pre-set air pressure stabilizer.

3. The method according to claim 1, characterized in that: After the steps of controlling the injection of the set mixed gas into the filter channel, controlling the light source emitter to emit red light to the filter channel, and obtaining the first illumination after eliminating the illumination interference intensity, the method further includes: Acquiring the current mixed gas concentration through the gas concentration sensor inside the filter channel; Compare and judge the current mixed gas concentration with a set mixed gas concentration threshold; If the current mixed gas concentration is lower than the set mixed gas concentration threshold, an opening signal is sent to the gas replenishment device so that the gas replenishment device starts to deliver the mixed gas according to a preset replenishment flow strategy.

4. The method according to claim 3, characterized in that If the current mixed gas concentration is lower than the set mixed gas concentration threshold, after the step of sending an opening signal to the gas replenishing device so that the gas replenishing device starts to deliver the mixed gas according to the preset replenishing flow strategy, the method further includes: If it is detected that the current mixed gas concentration is greater than the set mixed gas concentration threshold, the delivery valve of the gas replenishing device is closed.

5. The method according to claim 1, characterized in that After receiving the target gas detection instruction sent by the user end, the step of controlling the opening of the air intake valve to allow the exhaust gas to enter the detection chamber also includes: Acquiring the current pressure value of the exhaust gas through the pressure sensor in the detection chamber; If the pressure value exceeds the alarm threshold, an overpressure reminder is sent to the display.

6. The method according to claim 1, characterized in that After the step of determining the gas concentration of the target detection gas according to the third illumination and the second illumination by a gas sensor, and transmitting the gas concentration to a display screen in real time for dynamic display, the method further includes: Constructing an error correction model according to a plurality of interfering gas concentrations and measurement error data, wherein the measurement error data refers to the difference between the measured concentration and the actual concentration of the target detection gas; Acquiring the interfering gas concentration through the gas automatic identification module; The gas concentration of the target detection gas is calculated and corrected in real time through the error correction model.

7. The method according to claim 1, characterized in that After the step of determining the gas concentration of the target detection gas according to the third illumination and the second illumination by a gas sensor, and transmitting the gas concentration to a display screen in real time for dynamic display, the method further includes: The identification data of the gas automatic identification module is obtained. When it is identified that the concentration of the first target detection gas is less than the set threshold and the concentration of the second target detection gas is greater than the set threshold, the gas sensor is controlled to be replaced with a filter matching the second gas to be detected.

8. A server, characterized in that: The server includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the server to execute the method described in any one of claims 1-7.

9. A computer-readable storage medium comprising instructions, characterized in that: When the instructions are executed on a server, the server is caused to execute the method according to any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product is run on a server, the server is caused to execute the method according to any one of claims 1 to 7.

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