Ethylene concentration detection method, device, system and equipment and storage medium

Abstract

The invention provides an ethylene concentration detection method, device, system and equipment and a storage medium, and the method comprises the following steps: determining a first absorption peak value of a mixed gas when an output wavelength of an ethylene laser is under a mid-infrared ethylene central wavelength; determining a second absorption peak value of the methane when the output wavelength of the methane laser is under the central wavelength of the near-infrared methane; determining a target methane concentration based on a calibration model between the methane concentration and the absorption peak value under the near-infrared methane central wavelength; determining a third absorption peak-to-peak value of methane based on the calibration model between the methane concentration and the absorption peak-to-peak value under the central wavelength of intermediate infrared ethylene and the target methane concentration; based on the first absorption peak-to-peak value and the third absorption peak-to-peak value, determining a fourth absorption peak-to-peak value of ethylene under the central wavelength of intermediate infrared ethylene; and determining the target ethylene concentration based on a calibration model between the ethylene concentration and the absorption peak value under the mid-infrared ethylene central wavelength. According to the invention, the measurement precision of ethylene concentration can be improved.

Description

Technical Field

[0001] The present invention relates to the field of detection technologies, and in particular, to a method, device, system, equipment, and storage medium for detecting ethylene concentration. Background Art

[0002] Ethylene, as an important index gas for coal mine disasters, is usually generated in the early stage of coal seam spontaneous combustion. Real-time detection of ethylene concentration is of great significance for coal mine safety production, which can give early warnings and take corresponding measures to prevent disasters. However, the detection of ethylene in the coal mine environment faces many challenges, and the most prominent problem is the cross-interference of methane. Methane, as a common gas in coal mines, has overlapping absorption spectral lines with those of ethylene in the detection band, resulting in serious impacts on the accuracy and sensitivity of ethylene detection.

[0003] Currently, by using a near-infrared laser as a light source, accurate measurement of ethylene concentration can be achieved in the near-infrared band in the presence of methane interference. However, the absorption intensity of ethylene in the near-infrared band is generally one order of magnitude lower than that in the mid-infrared band, which means that in order to achieve the same detection accuracy, the optical path required in the near-infrared band is 10 times that in the mid-infrared band, greatly increasing the volume and complexity of the system.

[0004] Therefore, there is an urgent need for a method that can accurately measure ethylene concentration in the mid-infrared band when there is methane interference. Summary of the Invention

[0005] The present invention provides a method, device, system, equipment, and storage medium for detecting ethylene concentration, so as to solve the defect in the prior art that ethylene concentration cannot be accurately measured in the mid-infrared band, and achieve the purpose of accurately measuring ethylene concentration in the mid-infrared band when there is methane interference.

[0006] The present invention provides a method for detecting ethylene concentration, including: When the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength; When the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the peak value of the second absorption peak of the methane in the mixed gas at the near-infrared methane center wavelength; Based on the calibration model between methane concentration and absorption peak peak value at the near-infrared methane center wavelength, determining the target methane concentration corresponding to the peak value of the second absorption peak; Based on the calibration model between methane concentration and absorption peak peak value at the mid-infrared ethylene center wavelength and the target methane concentration, determining the peak value of the third absorption peak of the methane at the mid-infrared ethylene center wavelength; Based on the peak value of the first absorption peak and the peak value of the third absorption peak, determine the peak value of the fourth absorption peak of ethylene in the mixed gas at the mid-infrared ethylene center wavelength; Based on the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength, determine the target ethylene concentration corresponding to the peak value of the fourth absorption peak.

[0007] According to an ethylene concentration detection method provided by the present invention, when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the peak value of the first absorption peak of the mixed gas of methane and ethylene at the mid-infrared ethylene center wavelength includes: Adjust the input current of the ethylene laser to adjust the output wavelength of the ethylene laser to a wavelength range including the mid-infrared ethylene center wavelength; In the wavelength range, obtain the absorption spectrum line of the mixed gas through an ethylene photodetector; Based on the absorption spectrum line of the mixed gas, determine the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength.

[0008] According to an ethylene concentration detection method provided by the present invention, when the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the peak value of the second absorption peak of methane in the mixed gas at the near-infrared methane center wavelength includes: Adjust the input current of the methane laser to adjust the output wavelength of the methane laser to a wavelength range including the near-infrared methane center wavelength; In the wavelength range, obtain the first absorption spectrum line of methane through a methane photodetector; Based on the first absorption spectrum line of methane, determine the peak value of the second absorption peak of methane at the near-infrared methane center wavelength.

[0009] According to an ethylene concentration detection method provided by the present invention, the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength is determined based on the following method: When the output wavelength of the methane laser is at the near-infrared methane center wavelength, obtain the first absorption-free baseline when only nitrogen is included in the multi-gas chamber and the second absorption spectrum lines of methane at different methane concentrations in the multi-gas chamber through a methane photodetector; For each methane concentration, based on the first absorption-free baseline and the second absorption spectrum line of methane at the methane concentration, determine the first methane absorbance curve at the methane concentration; Based on the peak value of the methane absorption peak in each of the first methane absorbance curves and each of the methane concentrations, a calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane central wavelength is established.

[0010] According to an ethylene concentration detection method provided by the present invention, the calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength is determined based on the following method: At the mid-infrared ethylene central wavelength, second methane absorbance curves at different methane concentrations are obtained; Based on the peak value of the methane absorption peak in each of the second methane absorbance curves and the methane concentration, a calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength is established.

[0011] According to an ethylene concentration detection method provided by the present invention, the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength is determined based on the following method: When the output wavelength of the ethylene laser is at the mid-infrared ethylene central wavelength, a second non-absorption baseline when only nitrogen is included in the multi-gas chamber and a third absorption spectrum of the ethylene at different ethylene concentrations in the multi-gas chamber are obtained through an ethylene photodetector; For each of the ethylene concentrations, based on the second non-absorption baseline and the third absorption spectrum of the ethylene at the ethylene concentration, an ethylene absorbance curve at the ethylene concentration is determined; Based on the peak value of the ethylene absorption peak in each of the ethylene absorbance curves and each of the ethylene concentrations, a calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength is established.

[0012] The present invention also provides an ethylene concentration detection device, including: A first determination module, configured to determine a first absorption peak value of a mixed gas of methane and ethylene at the mid-infrared ethylene central wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene central wavelength; A second determination module, configured to determine a second absorption peak value of the methane in the mixed gas at the near-infrared methane central wavelength when the output wavelength of the methane laser is at the near-infrared methane central wavelength; A third determination module, configured to determine a target methane concentration corresponding to the second absorption peak value based on the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane central wavelength; A fourth determination module, configured to determine a third absorption peak value of the methane at the mid-infrared ethylene central wavelength based on the calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength and the target methane concentration; A fifth determination module, configured to determine a peak value of a fourth absorption peak of ethylene in the mixed gas at the mid-infrared ethylene center wavelength based on the peak value of the first absorption peak and the peak value of the third absorption peak; A sixth determination module, configured to determine a target ethylene concentration corresponding to the peak value of the fourth absorption peak based on a calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength.

[0013] The present invention further provides an ethylene concentration detection system, including an ethylene laser, a methane laser, an ethylene photodetector, a methane photodetector, a multi-gas chamber, and a control device, wherein the ethylene laser, the methane laser, the ethylene photodetector, and the methane photodetector are all connected to the control device; The ethylene laser is configured to send a laser at the mid-infrared ethylene center wavelength to the multi-gas chamber; The methane laser is configured to send a laser at the near-infrared methane center wavelength to the multi-gas chamber; The ethylene photodetector is configured to obtain an absorption spectrum line of a mixed gas of methane and ethylene in the multi-gas chamber within the mid-infrared ethylene center wavelength range; The methane photodetector is configured to obtain a first absorption spectrum line of the methane in the mixed gas within the near-infrared methane center wavelength range; The control device is configured to execute the ethylene concentration detection method described in any one of the above.

[0014] The present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein when the processor executes the computer program, the ethylene concentration detection method described in any one of the above is implemented.

[0015] The present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the ethylene concentration detection method described in any one of the above is implemented.

[0016] The present invention further provides a computer program product, including a computer program, and when the computer program is executed by a processor, the ethylene concentration detection method described in any one of the above is implemented.

[0017] The ethylene concentration detection method, device, system, equipment and storage medium provided by the present invention determine the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, and determine the peak value of the second absorption peak of methane in the mixed gas at the near-infrared methane center wavelength when the output wavelength of the methane laser is at the near-infrared methane center wavelength. Then, based on the calibration model between the methane concentration and the absorption peak value at the near-infrared methane center wavelength, the target methane concentration corresponding to the peak value of the second absorption peak is determined in real time. Based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration, the peak value of the third absorption peak of methane at the mid-infrared ethylene center wavelength is determined. Based on the peak value of the first absorption peak and the peak value of the third absorption peak, the peak value of the fourth absorption peak of ethylene in the mixed gas at the mid-infrared ethylene center wavelength is determined, so as to eliminate the interference of methane. Finally, based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, the target ethylene concentration corresponding to the peak value of the fourth absorption peak of pure ethylene is determined. By using the cooperation of the ethylene laser and the methane laser as two light sources, the interference of methane during the detection of ethylene concentration can be excluded, thereby improving the detection accuracy of determining ethylene concentration. In addition, by means of the absorption peak value calibration method, the problem that ethylene is band-absorbed within the scanning band range of the ethylene laser and the gas concentration cannot be inversely calculated directly by integrating the area of the absorbance curve is solved, and the complexity of the ethylene concentration detection system is simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a schematic diagram of the ethylene concentration detection system provided by the embodiment of the present invention.

[0020] Figure 2 It is a schematic flow chart of the ethylene concentration detection method provided by the embodiment of the present invention.

[0021] Figure 3 It is the absorption spectrum line of the mixed gas provided by the embodiment of the present invention.

[0022] Figure 4 It is the absorbance curves of the methane and ethylene mixed gases with different concentrations provided by the embodiment of the present invention.

[0023] Figure 5Absorption spectra of methane at different concentrations in the near-infrared methane central band provided by the embodiments of the present invention.

[0024] Figure 6 Schematic diagram of the calibration model between the peak value of the absorption peak of methane and the concentration provided by the embodiments of the present invention.

[0025] Figure 7 Absorption spectra of ethylene at different concentrations in the mid-infrared ethylene central band provided by the embodiments of the present invention.

[0026] Figure 8 Schematic diagram of the calibration model between the peak value of the absorption peak of ethylene and the concentration provided by the embodiments of the present invention.

[0027] Figure 9 Schematic diagram of the structure of the ethylene concentration detection device provided by the embodiments of the present invention.

[0028] Figure 10 Schematic diagram of the physical structure of an electronic device provided by the embodiments of the present invention. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Currently, due to the advantages of low cost and easy coupling of near-infrared lasers, near-infrared lasers are usually used as light sources for detecting ethylene concentration. However, the absorption intensity of ethylene gas in the near-infrared band is generally one order of magnitude lower than that in the mid-infrared band, which means that in order to achieve the same detection accuracy, the optical path required for near-infrared is 10 times that of mid-infrared, greatly increasing the volume of the system. In addition, in the mid-infrared band, the laser tuning range is spectral band absorption, and it is impossible to directly integrate the absorbance curve to invert the ethylene concentration. Therefore, there is an urgent need for a method to accurately measure ethylene concentration in the mid-infrared band in the presence of methane interference.

[0031] In view of the above problems, an embodiment of the present invention provides an ethylene concentration detection method. In this method, by increasing the real-time detection of methane concentration in the near-infrared band to deduct the interference of methane, and based on the established calibration model between the peak value of the absorption peak of the detected gas and the concentration, when detecting ethylene in the mid-infrared band, the absorption spectrum of ethylene within the tuning range of the laser is band absorption, and the absorbance curve cannot be directly integrated to invert the gas concentration. Thus, the problem is solved, and the ethylene concentration detection in the coal mine environment with methane interference is realized.

[0032] Next, the ethylene concentration detection system provided in the embodiment of the present invention will be introduced first. Figure 1 The following is a schematic diagram of the ethylene concentration detection system provided in the embodiment of the present invention. As Figure 1 shown, the detection system includes: a methane laser 1, an ethylene laser 2, a multi-pass gas cell 3, a methane photodetector 4, an ethylene photodetector 5, an embedded integrated circuit system 6, a host computer 7, and a gas mixer 8. Among them, the selection of the methane laser 1 and the ethylene laser 2 needs to be based on the central wavelength positions of methane and ethylene. The principle is to exclude the interference of other gases as much as possible near the selected gas central wavelength, otherwise it will affect the detection performance. Correspondingly, the selection of the methane photodetector 4 and the ethylene photodetector 5 needs to be based on the scanning wavelength range of the laser, and the response wavelength of the detector should also be within this range. The temperature control, current tuning of the laser, and the photoelectric conversion of the detector are all controlled by the embedded integrated circuit system 6. Methane, ethylene, and mixed gases with different concentrations are configured by the gas mixer 8 for high-purity nitrogen 9a, methane 9b, and ethylene 9c. During experimental measurement, the embedded integrated circuit system 6 controls the input current of the methane laser 1 or the ethylene laser 2 to change linearly, so as to linearly tune the output wavelength of the methane laser 1 or the ethylene laser 2, and then shine it into the multi-pass gas cell 3. When there is a gas to be detected in the multi-pass gas cell 3, it will absorb the light intensity, exit from the light outlet of the multi-pass gas cell 3, and then be detected by the methane photodetector 4 or the ethylene photodetector 5. After the detector obtains the optical signal and converts it into an electrical signal through photoelectric conversion, it is then uploaded to the host computer 7 for data processing.

[0033] Figure 2 The following is a schematic flowchart of the ethylene concentration detection method provided in the embodiment of the present invention. The execution subject of this embodiment is the above-mentioned embedded integrated circuit system or the host computer. As Figure 2 shown, the method includes the following: Step 201: When the output wavelength of the ethylene laser is at the mid-infrared ethylene central wavelength, determine the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene central wavelength.

[0034] In this step, by adjusting the input current of the ethylene laser, the purpose is to change the output wavelength of the ethylene laser so that the output wavelength of the ethylene laser can cover the mid-infrared ethylene center wavelength. Among them, the ethylene center wavelength refers to the center of the ethylene absorption spectrum, corresponding to the wavelength with the maximum absorption intensity.

[0035] Pass the laser of the ethylene laser at the mid-infrared ethylene center wavelength into the multi-gas chamber storing the mixed gas of methane and ethylene. The mixed gas will absorb the light. Using an ethylene photodetector, the overlapping absorption spectrum of the mixed gas in the multi-gas chamber can be scanned as the absorption spectral line of the mixed gas, and thus the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength can be determined based on this absorption spectral line.

[0036] Step 202: When the output wavelength of the methane laser is at the near-infrared methane center wavelength, determine the peak value of the second absorption peak of methane in the mixed gas at the near-infrared methane center wavelength.

[0037] In this step, by adjusting the input current of the methane laser, the purpose is to change the output wavelength of the methane laser so that the output wavelength of the methane laser can cover the near-infrared methane center wavelength. Among them, the methane center wavelength refers to the center of the methane absorption spectrum, corresponding to the wavelength with the maximum absorption intensity.

[0038] Pass the laser of the methane laser at the near-infrared methane center wavelength into the multi-gas chamber. Methane in the mixed gas will absorb the light. Using a methane photodetector, the absorption spectral line of methane can be obtained, and thus the peak value of the second absorption peak of methane at the near-infrared methane center wavelength can be determined based on this absorption spectral line.

[0039] Step 203: Based on the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength, determine the target methane concentration corresponding to the peak value of the second absorption peak.

[0040] In this step, the absorption spectral line without methane at the near-infrared methane center wavelength can be obtained in advance, and the absorption spectral lines of methane with different concentrations at the near-infrared methane center wavelength can be obtained. After extracting the absorbance curve of methane according to the Beer-Lambert law, based on this absorbance curve, the peak values of the absorption peaks of methane at different concentrations can be determined, and thus the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength can be established. Among them, the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength can be shown as formula (1): (1) Among them, represents the methane concentration, It represents the peak value of the absorption peak of methane at the center wavelength of near-infrared methane. C1 and C0 respectively represent the first-order coefficient and the constant coefficient obtained by least squares fitting.

[0041] After determining the peak value of the second absorption peak of methane at the center wavelength of near-infrared methane, by querying the above calibration model (1), the target methane concentration corresponding to the peak value of the second absorption peak can be inversely calculated.

[0042] Step 204: Based on the calibration model between the methane concentration and the peak value of the absorption peak at the center wavelength of mid-infrared ethylene and the target methane concentration, determine the peak value of the third absorption peak of methane at the center wavelength of mid-infrared ethylene.

[0043] In this step, the absorption spectrum line without methane at the center wavelength of mid-infrared ethylene can be obtained in advance, and the absorption spectrum lines of methane with different concentrations at the center wavelength of mid-infrared ethylene can be obtained. After extracting the absorbance curve of methane according to the Beer-Lambert law, based on this absorbance curve, the peak value of the absorption peak of methane at different concentrations can be determined, so as to establish a calibration model between the methane concentration and the peak value of the absorption peak at the center wavelength of mid-infrared ethylene. Among them, the calibration model between the methane concentration and the peak value of the absorption peak at the center wavelength of mid-infrared ethylene can be shown as formula (2): (2) Among them, represents the peak value of the absorption peak of methane at the center wavelength of mid-infrared ethylene, represents the methane concentration, and C3 and C2 respectively represent the first-order coefficient and the constant coefficient obtained by least squares fitting.

[0044] After determining the target methane concentration of methane, by querying the above calibration model (2), the peak value of the third absorption peak at the center wavelength of mid-infrared ethylene corresponding to the target methane concentration can be determined. Among them, the peak value of the third absorption peak can be inversely calculated by the following formula (3): .

[0045] Among them, is the total number of molecules per unit volume, is the gas absorption intensity, is the effective optical path, is the full width at half maximum of the Lorentz line shape.

[0046] Step 205: Based on the peak value of the first absorption peak and the peak value of the third absorption peak, determine the peak value of the fourth absorption peak of ethylene in the mixed gas at the center wavelength of mid-infrared ethylene.

[0047] In this step, the peak value of the first absorption peak is the peak value of the absorption peak of the mixed gas at the mid-infrared ethylene central wavelength, and the peak value of the third absorption peak is the peak value of the absorption peak of methane at the mid-infrared ethylene central wavelength. Therefore, by subtracting the peak value of the third absorption peak of methane from the peak value of the first absorption peak of the mixed gas, the interference of methane can be deducted, and the peak value of the fourth absorption peak of pure ethylene at the mid-infrared ethylene central wavelength can be obtained.

[0048] Exemplarily, the peak value of the fourth absorption peak can be determined according to the following formula (4): (4) Wherein, represents the peak value of the fourth absorption peak of ethylene at the mid-infrared ethylene central wavelength, represents the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene central wavelength, represents the peak value of the third absorption peak of methane at the mid-infrared ethylene central wavelength.

[0049] Step 206: Based on the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength, determine the target ethylene concentration corresponding to the peak value of the fourth absorption peak.

[0050] In this step, the absorption spectrum line without ethylene at the mid-infrared ethylene central wavelength can be obtained in advance, and the absorption spectrum lines of ethylene with different concentrations at the mid-infrared ethylene central wavelength can be obtained. After extracting the absorbance curve of ethylene according to the Beer-Lambert law, the peak value of the absorption peak of ethylene at different concentrations can be determined based on this absorbance curve, thereby establishing a calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength. Among them, the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength can be shown as formula (5): (5) Wherein, represents the ethylene concentration, and C5 and C4 respectively represent the first-order term coefficient and the constant term coefficient obtained by least squares fitting.

[0051] After determining the peak value of the fourth absorption peak of pure ethylene at the mid-infrared ethylene central wavelength, by querying the above calibration model (5), the target ethylene concentration corresponding to the peak value of the fourth absorption peak can be determined, that is, the ethylene concentration in the mixed gas. Exemplarily, the ethylene concentration can be determined according to the following formula (6): (6) Wherein, is the full width at half maximum of the Lorentzian line shape, is the total number of molecules per unit volume, is the gas absorption intensity, is the effective optical path.

[0052] The ethylene concentration detection method provided by the embodiment of the present invention determines the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength. When the output wavelength of the methane laser is at the near-infrared methane center wavelength, it determines the peak value of the second absorption peak of methane in the mixed gas at the near-infrared methane center wavelength. Then, based on the calibration model between the methane concentration and the absorption peak value at the near-infrared methane center wavelength, it determines the target methane concentration corresponding to the peak value of the second absorption peak in real time. Based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration, it determines the peak value of the third absorption peak of methane at the mid-infrared ethylene center wavelength. Based on the peak value of the first absorption peak and the peak value of the third absorption peak, it determines the peak value of the fourth absorption peak of ethylene in the mixed gas at the mid-infrared ethylene center wavelength, thereby eliminating the interference of methane. Finally, based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, it determines the target ethylene concentration corresponding to the peak value of the fourth absorption peak of pure ethylene. By using the cooperation of the dual light sources of the ethylene laser and the methane laser, the interference of methane during the detection of ethylene concentration can be excluded, thereby improving the detection accuracy of determining ethylene concentration. In addition, by using the absorption peak value calibration method, the problem that ethylene is band-absorbed within the scanning band range of the ethylene laser and the gas concentration cannot be directly inverted by integrating the area of the absorbance curve is solved, simplifying the complexity of the ethylene concentration detection system.

[0053] Exemplarily, on the basis of the above embodiment, when determining the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, it can be carried out in the following manner: Adjust the input current of the ethylene laser to adjust the output wavelength of the ethylene laser to a wavelength range including the mid-infrared ethylene center wavelength. Under this wavelength range, obtain the absorption spectrum of the mixed gas through an ethylene photodetector, and based on the absorption spectrum of the mixed gas, determine the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength.

[0054] Specifically, when there is no methane and ethylene mixed gas in the multi-gas chamber, the absorption baseline of the mixed gas can be determined in advance. For example, by adjusting the input current of the ethylene laser to change the output wavelength of the ethylene laser, where the change range of the output wavelength covers the vicinity of the selected mid-infrared ethylene center wavelength, that is, the wavelength range of the adjusted output wavelength of the ethylene laser will cover the mid-infrared ethylene center wavelength. Pass such a laser into the multi-gas chamber with nitrogen, and the ethylene photodetector will obtain the absorption spectrum of the multi-gas chamber without the mixed gas, and use this absorption spectrum as the absorption baseline of the mixed gas. Among them, the detected optical signal will be converted into an electrical signal by the ethylene photodetector, and after A / D conversion, the light absorption intensity of nitrogen at different sampling point times can be obtained. Based on the light absorption intensity at different sampling point times, the absorption baseline of the mixed gas can be determined.

[0055] In practical applications, similarly, by adjusting the input current of the ethylene laser to change the output wavelength of the ethylene laser, where the change range of the output wavelength covers the vicinity of the selected mid-infrared ethylene center wavelength. Pass such a laser into the multi-gas chamber with the mixed gas, and the mixed gas will absorb the laser, and the ethylene photodetector will obtain the absorption spectrum of the mixed gas.

[0056] Furthermore, the absorption intensity of nitrogen at each moment can be determined based on the absorption baseline, and the absorption intensity of the mixed gas at each moment can be determined based on the absorption spectrum, so as to extract the absorbance curve of the mixed gas according to the Beer-Lambert law. For example, the absorbance of the mixed gas can be determined according to the following formula (7): (7) Wherein, represents the absorbance of the mixed gas at time t, represents the light absorption intensity of nitrogen at time t, represents the light absorption intensity of the mixed gas at time t.

[0057] When the output wavelength of the ethylene laser corresponds to the selected mid-infrared ethylene center wavelength, the absorbance curve has a maximum value, that is, the maximum value of at each moment within the preset time period is determined as the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength.

[0058] In this embodiment, by adjusting the output wavelength of the ethylene laser to the mid-infrared ethylene center wavelength, by focusing on the mid-infrared ethylene center wavelength, the main absorption peak of methane in the mid-infrared band can be avoided, and the accuracy of the determined peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength can be improved.

[0059] Exemplarily, based on the above embodiments, when determining the peak value of the second absorption peak of methane in the mixed gas at the near-infrared methane central wavelength, where the output wavelength of the methane laser is at the near-infrared methane central wavelength, the following method can be adopted: Adjust the input current of the methane laser to adjust the output wavelength of the methane laser to a wavelength range including the near-infrared methane central wavelength. Under this wavelength range, after obtaining the first absorption spectrum of methane through a methane photodetector, based on the first absorption spectrum of methane, determine the peak value of the second absorption peak of methane at the near-infrared methane central wavelength.

[0060] Specifically, the methane-free absorption baseline of methane can be determined in advance when there is no methane in the multi-gas chamber. For example, by adjusting the input current of the methane laser to change the output wavelength of the methane laser, where the change range of the output wavelength covers the vicinity of the selected near-infrared methane central wavelength, that is, the wavelength range of the adjusted output wavelength of the methane laser will cover the near-infrared methane central wavelength. Pass such laser into the multi-gas chamber filled with nitrogen, and the absorption spectrum when there is no methane in the multi-gas chamber can be obtained by using a methane photodetector. Take this absorption spectrum as the methane-free absorption baseline. Among them, the methane photodetector will convert the detected optical signal into an electrical signal, and after A / D conversion, the light absorption intensity of nitrogen at different sampling time points can be obtained. Based on the light absorption intensity at different sampling time points, the methane-free absorption baseline can be determined.

[0061] In practical applications, similarly, by adjusting the input current of the methane laser to change the output wavelength of the methane laser, where the change range of the output wavelength covers the vicinity of the selected near-infrared methane central wavelength. Pass such laser into the multi-gas chamber filled with the mixed gas, and methane in the mixed gas will absorb the laser. The absorption spectrum of methane in the mixed gas can be obtained by using a methane photodetector.

[0062] Furthermore, the absorption intensity of nitrogen at each moment can be determined based on the methane-free absorption baseline, and the absorption intensity of methane in the mixed gas at each moment can be determined based on the absorption spectrum. Thus, according to the Beer-Lambert law, the absorbance curve of methane can be extracted. The relationship between the initial light intensity in the methane-free absorption baseline and the absorbed light intensity in the absorption spectrum can be expressed as shown in the following formula (8): (8) Among them, A represents the absorbance of methane, represents the light absorption intensity at time t when there is no methane, represents the light absorption intensity of methane at time t, is the total number of molecules per unit volume, is the gas absorption intensity, is the normalized Lorentz absorption spectral line shape, is the gas concentration, is the effective optical path, is the full width at half maximum of the Lorentz line shape, is the wavelength, is the central wavelength of the Lorentz line shape.

[0063] According to formula (8), the following formula (9) can be obtained to determine the absorbance of methane: (9) where, represents the absorbance of methane at time t.

[0064] When the output wavelength of the methane laser corresponds to the selected near-infrared methane central wavelength, the absorbance curve of methane has a maximum value, that is, the maximum value in at each moment within the preset time period is determined as the peak value of the second absorption peak of methane at the near-infrared methane central wavelength.

[0065] In this embodiment, adjusting the output wavelength of the methane laser to the vicinity of the mid-infrared methane central wavelength can improve the accuracy of the peak value of the second absorption peak of methane in the mixed gas determined at the near-infrared methane central wavelength.

[0066] When inversely calculating the methane concentration based on the peak value of the second absorption peak of methane at the near-infrared methane central wavelength, the methane concentration can be as shown in the following formula (10): (10) where, represents the methane concentration, represents the value of the Lorentz line shape function corresponding to the near-infrared methane central wavelength.

[0067] Next, the establishment processes of the calibration models between the methane concentration and the peak value of the absorption peak at the near-infrared methane central wavelength, the calibration models between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength, and the calibration models between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene central wavelength will be described in detail. Among them, when the temperature, pressure, optical path, and Lorentz full width at half maximum are kept constant, the peak value of the absorption peak and the concentration of the detected gas are linearly related.

[0068] For the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane central wavelength, it can be determined based on the following method: When the output wavelength of the methane laser is at the near-infrared methane center wavelength, the first absorption-free baseline when only nitrogen is included in the multi-gas chamber and the second absorption spectrum of methane at different methane concentrations in the multi-gas chamber are obtained through a methane photodetector. For each methane concentration, after determining the first methane absorbance curve at the methane concentration based on the first absorption-free baseline and the second absorption spectrum of methane at the methane concentration, a calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength is established based on the peak value of the absorption peak of methane in each first methane absorbance curve and each methane concentration.

[0069] Specifically, similar to the previous embodiment, after adjusting the output wavelength of the methane laser to be within the near-infrared methane center wavelength range, the laser is input into the multi-gas chamber containing only nitrogen. At this time, the absorption spectrum of nitrogen present in the multi-gas chamber can be scanned through a methane photodetector as the first absorption-free baseline of methane. Then, methane is input into the multi-gas chamber, and the methane concentration is continuously changed. At each methane concentration, the second absorption spectrum of methane at the near-infrared methane center wavelength is obtained.

[0070] For any methane concentration, the ratio between the absorption intensity at each moment in the first absorption-free baseline and the absorption intensity at each moment in the second absorption spectrum corresponding to this methane concentration can be determined, and after taking the logarithm of this ratio, the first methane absorbance curve at this methane concentration can be obtained. The maximum value in the first methane absorbance curve is determined as the peak value of the absorption peak of methane at this methane concentration.

[0071] In the above manner, the peak value of the absorption peak of methane at each methane concentration can be determined, and thus the least squares method can be used for linear fitting to establish a calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength.

[0072] In this embodiment, through the first absorption-free baseline without methane and the second absorption spectrum of methane at different methane concentrations, the first methane absorbance curve at different methane concentrations can be determined. Thus, based on the peak value of the absorption peak of methane in the first methane absorbance curve at each methane concentration and the methane concentration, an accurate calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength can be fitted. Subsequently, based on this calibration model, the methane concentration can be accurately deduced based on the peak value of the absorption peak of methane.

[0073] For the calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength, it can be determined based on the following method: At the mid-infrared ethylene center wavelength, the second methane absorbance curves at different methane concentrations are obtained, and a calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength is established based on the peak value of the absorption peak of methane in each second methane absorbance curve and the methane concentration.

[0074] Specifically, through simulation, the second methane absorbance curve corresponding to different methane concentrations at the central wavelength of mid-infrared ethylene can be obtained, and the maximum value in the second methane absorbance curve is determined as the peak value of the methane absorption peak at this methane concentration when the central wavelength of mid-infrared ethylene is reached.

[0075] According to the above method, the peak value of the methane absorption peak at each methane concentration when the central wavelength of mid-infrared ethylene is reached can be determined. Thus, the least squares method can be used for linear fitting to establish a calibration model between the methane concentration and the peak value of the absorption peak at the central wavelength of mid-infrared ethylene.

[0076] In this embodiment, by obtaining the second methane absorbance curves at different methane concentrations at the central wavelength of mid-infrared ethylene, based on the peak value of the methane absorption peak and the methane concentration in the second methane absorbance curves at each methane concentration, an accurate calibration model between the methane concentration and the peak value of the absorption peak at the central wavelength of mid-infrared ethylene is fitted. Subsequently, based on this calibration model and the methane concentration of methane, the peak value of the methane absorption peak at the central wavelength of mid-infrared ethylene can be accurately determined.

[0077] For the calibration model between the ethylene concentration and the peak value of the absorption peak at the central wavelength of mid-infrared ethylene, it can be determined based on the following method: When the output wavelength of the ethylene laser is at the central wavelength of mid-infrared ethylene, the second non-absorbing baseline when only nitrogen is included in the multi-gas chamber and the third absorption spectrum of ethylene at different ethylene concentrations in the multi-gas chamber are obtained through an ethylene photodetector. For each ethylene concentration, after determining the ethylene absorbance curve based on the second non-absorbing baseline and the third absorption spectrum of ethylene at the ethylene concentration, a calibration model between the ethylene concentration and the peak value of the absorption peak at the central wavelength of mid-infrared ethylene is established based on the peak value of the ethylene absorption peak in each ethylene absorbance curve and each ethylene concentration.

[0078] Specifically, after adjusting the output wavelength of the ethylene laser to be within the range of the central wavelength of mid-infrared ethylene, the laser is input into the multi-gas chamber containing only nitrogen. At this time, the second non-absorbing baseline of ethylene at the central wavelength of mid-infrared ethylene can be obtained through an ethylene photodetector. Then, ethylene is input into the multi-gas chamber, and the concentration of ethylene is continuously changed. At each ethylene concentration, the third absorption spectrum of ethylene at the central wavelength of mid-infrared ethylene is obtained.

[0079] For any ethylene concentration, the ratio between the absorption intensity at each moment in the second non-absorbing baseline and the absorption intensity at each moment in the third absorption spectrum corresponding to this ethylene concentration can be determined, and after taking the logarithm of this ratio, the ethylene absorbance curve at this ethylene concentration can be obtained. The maximum value in the ethylene absorbance curve is determined as the peak value of the ethylene absorption peak at this ethylene concentration when the central wavelength of mid-infrared ethylene is reached.

[0080] In the above manner, the peak value of the absorption peak of ethylene at each ethylene concentration at the mid-infrared ethylene center wavelength can be determined, so that linear fitting can be performed using the least squares method to establish a calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength.

[0081] In this embodiment, through the second non-absorption baseline without ethylene and the third absorption spectrum of ethylene at different ethylene concentrations, the ethylene absorbance curve at different ethylene concentrations at the mid-infrared ethylene center wavelength can be determined. Then, based on the peak value of the absorption peak of ethylene and the ethylene concentration in the ethylene absorbance curve at each ethylene concentration, an accurate calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength can be fitted. Subsequently, based on this calibration model and the peak value of the absorption peak of ethylene at the mid-infrared ethylene center wavelength, the ethylene concentration can be accurately determined.

[0082] Taking Figure 1 the detection system shown as a basis, the ethylene concentration in the mixed gas in the multi-gas chamber 3 is detected. Among them, the pressure is the atmospheric environment, that is, calculated according to one standard atmosphere, and the temperature is the normal temperature of 298 K. The center wavelength of the selected methane laser is 1654 nm, and the center wavelength of the ethylene laser is 3170.1 nm; the ethylene laser is reflected 27 times in the gas chamber, and the effective optical path is 1.2 m. The methane laser is not reflected in the gas chamber and directly irradiates the detector, and the effective optical path is 6 cm.

[0083] First, nitrogen is introduced into the multi-gas chamber, and the ethylene laser is scanned to obtain the non-absorption spectrum. The average value of 20 scan results is taken as the non-absorption baseline. Subsequently, a mixed gas of methane and ethylene with different concentrations is introduced into the multi-gas chamber, and the absorption spectrum of the mixed gas as shown in Figure 3 is scanned again. Through the absorption spectrum, the sampling value at each sampling point, that is, the absorption intensity, can be viewed. Among them, Figure 3 is the absorption spectrum of the mixed gas provided by the embodiment of the present invention. The logarithm is taken after comparing the absorption intensity in the non-absorption baseline with the absorption intensity in the absorption spectrum to obtain the aliased absorption spectrum as shown in Figure 4 , that is, the absorbance curve. Through this absorbance curve, the absorbance of the mixed gas at different concentrations at different sampling points can be viewed. Among them, Figure 4 is the absorbance curve of the mixed gas of methane and ethylene with different concentrations provided by the embodiment of the present invention.

[0084] Since the aliased absorption spectrum as shown in Figure 4 contains the absorption of both methane and ethylene, in order to determine the concentration of ethylene, it is necessary to first deduct the absorption peak of methane and then perform the inversion of the ethylene concentration. Figure 5Absorption spectra of methane at different concentrations in the near-infrared methane central band provided by the embodiments of the present invention are shown as Figure 5 follows. The peak values of the absorption peaks of methane at different concentrations in the near-infrared methane central band can be determined, so that a calibration model between the peak value of the absorption peak and the concentration can be established by fitting. Figure 6 The schematic diagram of the calibration model between the peak value of the absorption peak and the concentration of methane provided by the embodiments of the present invention is shown as Figure 6 follows. The peak value of the absorption peak of methane can also be understood as the absorbance of methane, and the correlation coefficient between the peak value of the absorption peak and the concentration reaches 0.999. Affected by the noise level, the detection limit of methane is 500 ppm.

[0085] After the real-time concentration of methane is inversely calculated based on the calibration model between the peak value of the absorption peak and the concentration of methane, it is necessary to calculate the corresponding peak value of the absorption peak at the selected central wavelength of 3170.1 nm of ethylene in the mid-infrared band according to this concentration value. Since the peak value of methane at this wavelength is weak, it is difficult to establish a calibration model between the peak value of the absorption peak and the concentration through actual measurement. The present invention uses the simulation result as the calculation standard. After obtaining the peak value of the absorption peak of methane at this central wavelength, subtracting this value from the peak value at the corresponding wavelength of the aliased absorption spectrum can obtain the peak value of the absorption peak of single ethylene.

[0086] In order to complete the concentration inversion of ethylene, it is necessary to establish a calibration model between the concentration and the peak value of the absorption peak of ethylene at the selected central wavelength of 3170.1 nm. Figure 7 Absorption spectra of ethylene at different concentrations in the mid-infrared ethylene central band provided by the embodiments of the present invention are shown as Figure 7 follows. The peak values of the absorption peaks of ethylene at different concentrations in the mid-infrared ethylene central band can be determined, so that a calibration model between the peak value of the absorption peak and the concentration can be established by fitting. Figure 8 The schematic diagram of the calibration model between the peak value of the absorption peak and the concentration of ethylene provided by the embodiments of the present invention is shown as Figure 8 follows. The fitting coefficient reaches 0.9993, indicating that there is a good linear relationship between the two, and the establishment of this calibration model is reasonable. In actual measurement, as long as the peak value of the absorption peak of single ethylene is obtained and substituted into the determined calibration model, the concentration inversion calculation of ethylene can be completed. Considering the noise level, the detection limit of ethylene concentration can reach 5 ppm, which proves the effectiveness of the method proposed by the present invention.

[0087] As Figure 1As shown in the figure, an embodiment of the present invention further provides an ethylene concentration detection system, which includes an ethylene laser, a methane laser, an ethylene photodetector, a methane photodetector, a multi-gas chamber, and a control device. The ethylene laser, the methane laser, the ethylene photodetector, and the methane photodetector are all connected to the control device. The ethylene laser is used to send a laser with a mid-infrared ethylene center wavelength to the multi-gas chamber. The methane laser is used to send a laser with a near-infrared methane center wavelength to the multi-gas chamber. The ethylene photodetector is used to obtain the absorption spectrum of the methane and ethylene mixed gas in the multi-gas chamber in the mid-infrared ethylene center wavelength range. The methane photodetector is used to obtain the first absorption spectrum of the methane in the mixed gas in the near-infrared methane center wavelength range. The control device is used to execute the ethylene concentration detection method described in any of the above embodiments.

[0088] The ethylene concentration detection device provided by the present invention will be described below. The ethylene concentration detection device described below can be mutually corresponding and referenced with the ethylene concentration detection method described above.

[0089] Figure 9 It is a schematic structural diagram of the ethylene concentration detection device provided by an embodiment of the present invention. Refer to Figure 9 As shown in the figure, the ethylene concentration detection device 900 includes: The first determination module 11 is used to determine the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength. The second determination module 12 is used to determine the peak value of the second absorption peak of the methane in the mixed gas at the near-infrared methane center wavelength when the output wavelength of the methane laser is at the near-infrared methane center wavelength. The third determination module 13 is used to determine the target methane concentration corresponding to the peak value of the second absorption peak based on the calibration model between the methane concentration and the peak value of the absorption peak at the near-infrared methane center wavelength. The fourth determination module 14 is used to determine the peak value of the third absorption peak of the methane at the mid-infrared ethylene center wavelength based on the calibration model between the methane concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength and the target methane concentration. The fifth determination module 15 is used to determine the peak value of the fourth absorption peak of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength based on the peak value of the first absorption peak and the peak value of the third absorption peak. The sixth determination module 16 is used to determine the target ethylene concentration corresponding to the peak value of the fourth absorption peak based on the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength.

[0090] In an exemplary embodiment, the first determination module 11 is specifically configured to: Adjust the input current of the ethylene laser to adjust the output wavelength of the ethylene laser to a wavelength range including the mid-infrared ethylene center wavelength; Under the wavelength range, obtain the absorption spectral line of the mixed gas through an ethylene photodetector; Based on the absorption spectral line of the mixed gas, determine the peak value of the first absorption peak of the mixed gas at the mid-infrared ethylene center wavelength.

[0091] In an exemplary embodiment, the second determination module 12 is specifically configured to: Adjust the input current of the methane laser to adjust the output wavelength of the methane laser to a wavelength range including the near-infrared methane center wavelength; Under the wavelength range, obtain the first absorption spectral line of the methane through a methane photodetector; Based on the first absorption spectral line of the methane, determine the peak value of the second absorption peak of the methane at the near-infrared methane center wavelength.

[0092] In an exemplary embodiment, the calibration model between the methane concentration and the absorption peak peak value at the near-infrared methane center wavelength is determined based on the following method: When the output wavelength of the methane laser is at the near-infrared methane center wavelength, obtain the first non-absorption baseline when only nitrogen is included in the multi-gas chamber and the second absorption spectral line of the methane at different methane concentrations in the multi-gas chamber through a methane photodetector; For each methane concentration, based on the first non-absorption baseline and the second absorption spectral line of the methane at the methane concentration, determine the first methane absorbance curve at the methane concentration; Based on the absorption peak peak value of the methane in each of the first methane absorbance curves and each methane concentration, establish a calibration model between the methane concentration and the absorption peak peak value at the near-infrared methane center wavelength.

[0093] In an exemplary embodiment, the calibration model between the methane concentration and the absorption peak peak value at the mid-infrared ethylene center wavelength is determined based on the following method: At the mid-infrared ethylene center wavelength, obtain the second methane absorbance curves at different methane concentrations; Based on the absorption peak peak value of the methane in each of the second methane absorbance curves and the methane concentration, establish a calibration model between the methane concentration and the absorption peak peak value at the mid-infrared ethylene center wavelength.

[0094] In an exemplary embodiment, the calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength is determined based on the following method: When the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, the second non-absorption baseline when only nitrogen is included in the multi-gas chamber and the third absorption spectrum of the ethylene in the multi-gas chamber at different ethylene concentrations are obtained through an ethylene photodetector; For each of the ethylene concentrations, based on the second non-absorption baseline and the third absorption spectrum of the ethylene at the ethylene concentration, the ethylene absorbance curve at the ethylene concentration is determined; Based on the peak value of the absorption peak of the ethylene in each of the ethylene absorbance curves and each of the ethylene concentrations, a calibration model between the ethylene concentration and the peak value of the absorption peak at the mid-infrared ethylene center wavelength is established.

[0095] The device of this embodiment can be used to execute the method of any one of the embodiments on the side of the ethylene concentration detection method. The specific implementation process and technical effects are similar to those in the embodiments on the side of the ethylene concentration detection method. For details, reference can be made to the detailed introduction in the embodiments on the side of the ethylene concentration detection method, which will not be elaborated here.

[0096] Figure 10 The following is a schematic physical structure diagram of an electronic device provided by an embodiment of the present invention, as Figure 10As shown in the figure, the electronic device may include: a processor 1010, a communications interface 1020, a memory 1030, and a communication bus 1040. Among them, the processor 1010, the communications interface 1020, and the memory 1030 complete communication with each other through the communication bus 1040. The processor 1010 may call logic instructions in the memory 1030 to execute the ethylene concentration detection method, which includes: when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength; when the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the peak value of the second absorption peak of the methane in the mixed gas at the near-infrared methane center wavelength; based on the calibration model between the methane concentration and the absorption peak value at the near-infrared methane center wavelength, determining the target methane concentration corresponding to the second absorption peak value; based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration, determining the peak value of the third absorption peak of the methane at the mid-infrared ethylene center wavelength; based on the first absorption peak value and the third absorption peak value, determining the peak value of the fourth absorption peak of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength; based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, determining the target ethylene concentration corresponding to the fourth absorption peak value.

[0097] In addition, when the logic instructions in the above-mentioned memory 1030 are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0098] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the ethylene concentration detection method provided by the above-mentioned various methods. The method includes: when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength; when the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the peak value of the second absorption peak of the methane in the mixed gas at the near-infrared methane center wavelength; based on the calibration model between the methane concentration and the absorption peak value at the near-infrared methane center wavelength, determining the target methane concentration corresponding to the second absorption peak value; based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration, determining the peak value of the third absorption peak of the methane at the mid-infrared ethylene center wavelength; based on the first absorption peak value and the third absorption peak value, determining the peak value of the fourth absorption peak of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength; based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, determining the target ethylene concentration corresponding to the fourth absorption peak value.

[0099] On another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is implemented to execute the ethylene concentration detection method provided by the above-mentioned various methods. The method includes: when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the peak value of the first absorption peak of the methane and ethylene mixed gas at the mid-infrared ethylene center wavelength; when the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the peak value of the second absorption peak of the methane in the mixed gas at the near-infrared methane center wavelength; based on the calibration model between the methane concentration and the absorption peak value at the near-infrared methane center wavelength, determining the target methane concentration corresponding to the second absorption peak value; based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration, determining the peak value of the third absorption peak of the methane at the mid-infrared ethylene center wavelength; based on the first absorption peak value and the third absorption peak value, determining the peak value of the fourth absorption peak of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength; based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, determining the target ethylene concentration corresponding to the fourth absorption peak value.

[0100] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative labor.

[0101] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting ethylene concentration, characterized in that: include: When the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength, determining the first absorption peak value of the mixed gas of methane and ethylene at the mid-infrared ethylene center wavelength; When the output wavelength of the methane laser is at the near-infrared methane center wavelength, determining the second absorption peak value of the methane in the mixed gas at the near-infrared methane center wavelength; Determine the target methane concentration corresponding to the second absorption peak value based on a calibration model between the methane concentration and the absorption peak value at the near-infrared methane central wavelength; Determine the third absorption peak value of methane at the mid-infrared ethylene center wavelength based on the calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration; Determine a fourth absorption peak value of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength based on the first absorption peak value and the third absorption peak value; Based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength, the target ethylene concentration corresponding to the fourth absorption peak value is determined.

2. The method for detecting ethylene concentration according to claim 1, characterized in that: The method of determining the first absorption peak value of the mixed gas of methane and ethylene at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength comprises: adjusting the input current of the ethylene laser to adjust the output wavelength of the ethylene laser to a wavelength range including the mid-infrared ethylene center wavelength; Acquiring the absorption spectrum of the mixed gas within the wavelength range through an ethylene photoelectric detector; Based on the absorption spectrum of the mixed gas, the first absorption peak value of the mixed gas at the mid-infrared ethylene center wavelength is determined.

3. The method for detecting ethylene concentration according to claim 1, characterized in that: The step of determining the second absorption peak value of the methane in the mixed gas at the near-infrared methane center wavelength when the output wavelength of the methane laser is at the near-infrared methane center wavelength comprises: adjusting the input current of the methane laser to adjust the output wavelength of the methane laser to a wavelength range including the near-infrared methane center wavelength; Acquiring a first absorption spectrum line of methane by a methane photoelectric detector within the wavelength range; Based on the first absorption spectrum of methane, the second absorption peak value of methane at the near-infrared methane central wavelength is determined.

4. The method for detecting ethylene concentration according to any one of claims 1 to 3, characterized in that: The calibration model between the methane concentration and the absorption peak value at the near-infrared methane central wavelength is determined based on the following method: When the output wavelength of the methane laser is at the near-infrared methane center wavelength, a first non-absorption baseline when only nitrogen is included in the multi-ventilation chamber and a second absorption spectrum line of methane at different methane concentrations in the multi-ventilation chamber are obtained by a methane photoelectric detector; For each of the methane concentrations, determining a first methane absorbance curve at the methane concentration based on the first non-absorption baseline and a second absorption spectrum of the methane at the methane concentration; Based on the absorption peak value of methane in each of the first methane absorbance curves and each of the methane concentrations, a calibration model between the methane concentration and the absorption peak value at the near-infrared methane central wavelength is established.

5. The method for detecting ethylene concentration according to any one of claims 1 to 3, characterized in that: The calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength is determined based on the following method: At the mid-infrared ethylene center wavelength, a second methane absorbance curve at different methane concentrations is obtained; Based on the absorption peak value of methane in each of the second methane absorbance curves and the methane concentration, a calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength is established.

6. The method for detecting ethylene concentration according to any one of claims 1 to 3, characterized in that: The calibration model between the ethylene concentration and the peak absorption value at the mid-infrared ethylene center wavelength is determined based on the following method: When the output wavelength of the ethylene laser is at the central wavelength of mid-infrared ethylene, a second non-absorption baseline when only nitrogen is included in the multi-ventilation chamber and a third absorption spectrum line of ethylene at different ethylene concentrations in the multi-ventilation chamber are obtained by an ethylene photodetector; For each of the ethylene concentrations, determining an ethylene absorbance curve at the ethylene concentration based on the second non-absorption baseline and the third absorption spectrum of ethylene at the ethylene concentration; Based on the absorption peak value of ethylene in each of the ethylene absorbance curves and each of the ethylene concentrations, a calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength is established.

7. An ethylene concentration detection device, characterized in that: include: A first determination module is used to determine the first absorption peak value of the mixed gas of methane and ethylene at the mid-infrared ethylene center wavelength when the output wavelength of the ethylene laser is at the mid-infrared ethylene center wavelength; A second determination module is used to determine the second absorption peak value of the methane in the mixed gas at the near-infrared methane center wavelength when the output wavelength of the methane laser is at the near-infrared methane center wavelength; A third determination module is used to determine the target methane concentration corresponding to the second absorption peak value based on a calibration model between the methane concentration and the absorption peak value at the near-infrared methane central wavelength; A fourth determination module, configured to determine a third absorption peak value of methane at the mid-infrared ethylene center wavelength based on a calibration model between the methane concentration and the absorption peak value at the mid-infrared ethylene center wavelength and the target methane concentration; A fifth determination module, configured to determine a fourth absorption peak value of the ethylene in the mixed gas at the mid-infrared ethylene center wavelength based on the first absorption peak value and the third absorption peak value; The sixth determination module is used to determine the target ethylene concentration corresponding to the fourth absorption peak value based on the calibration model between the ethylene concentration and the absorption peak value at the mid-infrared ethylene center wavelength.

8. An ethylene concentration detection system, characterized in that: It includes an ethylene laser, a methane laser, an ethylene photoelectric detector, a methane photoelectric detector, a multi-ventilation chamber and a control device, wherein the ethylene laser, the methane laser, the ethylene photoelectric detector and the methane photoelectric detector are all connected to the control device; The ethylene laser is used to send laser light of mid-infrared ethylene center wavelength to the multi-vent chamber; The methane laser is used to send near-infrared methane central wavelength laser light to the multi-ventilation chamber; The ethylene photoelectric detector is used to obtain the absorption spectrum of the mixed gas of methane and ethylene in the multi-ventilation chamber within the mid-infrared ethylene central wavelength range; The methane photoelectric detector is used to obtain the first absorption spectrum line of the methane in the mixed gas within the near-infrared methane central wavelength range; The control device is used to execute the ethylene concentration detection method as described in any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the ethylene concentration detection method according to any one of claims 1 to 6 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the ethylene concentration detection method according to any one of claims 1 to 6 is implemented.

Images