Data processing method, system and readable medium for Fourier infrared gas analyzer

Abstract

The present invention relates to a data processing method, system and readable medium of a Fourier infrared gas analyzer. The data processing method comprises: collecting a zeroing spectrum SPE0'; performing Fourier interpolation on an air background spectrum SPE0 and a zeroing spectrum SPE0' respectively to obtain a spectrum SPE 0_ and spectral SPE 0_ '; Select the spectrum SPE respectively 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k '; Spectral segment SPE 0_ k 'After left or right shift and SPE 0_ k Calculate the matching degree; select the offset wavenumber point corresponding to the highest matching degree as the wavenumber drift, and obtain the wavenumber drift corresponding to the two target bands respectively. D k ; According to the wave number drift D k And the wave number average of the target band X k The spectrum drift and the proportional drift are calculated, and the spectrum to be corrected is drift-corrected according to the spectrum drift and the proportional drift. The present invention can effectively improve the accuracy of gas analysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas analysis, and in particular relates to a data processing method, system and readable medium of a Fourier infrared gas analyzer. Background Art

[0002] During the actual operation of the Fourier infrared gas analyzer, the wavelength of the He-Ne laser will change due to temperature changes, causing the infrared spectrum to drift in the horizontal axis. In addition, the optical path of the He-Ne laser may shift due to the influence of transportation vibration, which will also cause the infrared spectrum to drift in the horizontal axis. When the horizontal axis of the spectrum drifts, the detection result deviation of the Fourier infrared gas analyzer will increase, and even give erroneous data. Summary of the invention

[0003] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the objects of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the objects of the present invention is to provide a data processing method, system and readable medium for a Fourier infrared gas analyzer that meets one or more of the above-mentioned requirements.

[0004] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0005] A data processing method for a Fourier infrared gas analyzer comprises the following steps:

[0006] S1, collecting the zeroing spectrum SPE0' by passing pure air into the air for zeroing;

[0007] S2, respectively perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0' to obtain the spectrum SPE 0_ and spectral SPE 0_ ';

[0008] S3, select the spectrum SPE respectively 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k '; where the target band is the band corresponding to the water vapor absorption peak, k The values ​​are 1 and 2, representing two target bands respectively;

[0009] S4, spectrum segment SPE 0_ k 'Move left N After the wave number points and SPE 0_ k Calculate the matching degree and convert the spectrum segment SPE0_ k 'Move left N -1 wave number point and SPE 0_ k Calculate the matching degree, and so on, and convert the spectrum segment SPE 0_ k 'Move left by 1 wave number point and then compare with SPE 0_ k Calculate the matching degree; then divide the spectrum segment SPE 0_ k 'Move right by one wave number point and then compare with SPE 0_ k Calculate the matching degree and convert the spectrum segment SPE 0_ k 'Move right 2 wave number points and SPE 0_ k Calculate the matching degree, and so on, and convert the spectrum segment SPE 0_ k 'Move right N After the wave number points and SPE 0_ k Calculate the matching degree; select the offset wavenumber point corresponding to the highest matching degree as the wavenumber drift, and obtain the wavenumber drift corresponding to the two target bands respectively. D k ; Among them, the wave number drift corresponding to the left shift is D k Take a negative value and shift the corresponding wave number drift to the right D k Take positive value, N is an integer greater than 1;

[0010] S5. Based on the wave number drift of the two target bands D k And the wave number average of the target band X k Calculate the spectral drift and proportional drift;

[0011] S6. Perform drift correction on the spectrum to be corrected according to the spectral drift amount and the proportional drift amount.

[0012] As a preferred solution, in step S5, the spectral drift amount P for:

[0013] ;

[0014] Proportional drift Q for:

[0015] .

[0016] As a preferred solution, in step S6, before drift correction is performed on the spectrum to be corrected, the spectrum to be corrected SPE conduct M Interpolate by multiples to get the interpolated spectrum SPE * .

[0017] As a preferred solution, in step S6, the spectrum after drift correction is:

[0018] ;

[0019] in, i is the wave number, round is the rounding function.

[0020] As a preferred embodiment, the M The value must be an integer multiple of 50.

[0021] As a preferred embodiment, the M The value is 100.

[0022] As a preferred solution, the two target bands are 1700-1800 cm -1 and 3700~3800cm -1 .

[0023] The present invention also provides a data processing system for a Fourier infrared gas analyzer, which uses the data processing method described in the above scheme, and the data processing system comprises:

[0024] A collection module, used for collecting a zeroing spectrum SPE0' which is zeroed by passing pure air;

[0025] The interpolation module is used to perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0' to obtain the spectrum SPE 0_ and spectral SPE 0_ ';

[0026] Selection module, used to select spectra SPE separately 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k ';

[0027] Computation module for spectral segment SPE 0_ k 'After left or right shift and SPE 0_ k Calculate the matching degree;

[0028] The selection module is also used to select the offset wave number point corresponding to the highest matching degree as the wave number drift, and obtain the wave number drift corresponding to the two target bands respectively. D k ;

[0029] The calculation module is also used to calculate the wave number drift of the two target bands. D k And the wave number average of the target band X k Calculate the spectral drift and proportional drift;

[0030] The correction module is used to perform drift correction on the spectrum to be corrected according to the spectral drift amount and the proportional drift amount.

[0031] The present invention also provides a readable medium, wherein instructions are stored in the readable medium. When the instructions are executed on a computer, the computer executes the data processing method as described in any of the above schemes.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] When the present invention performs spectral drift correction on the Fourier infrared gas analyzer, the band corresponding to the water vapor absorption peak is used as the target band, two target bands are selected for offset matching calculation, and then the offset wavenumber point corresponding to the highest matching degree is selected as the wavenumber drift amount, and then the spectral drift amount and the proportional drift amount are calculated according to the wavenumber drift amounts of the two target bands and the wavenumber average value of the target bands. Finally, the spectrum to be corrected is drift corrected according to the spectral drift amount and the proportional drift amount, thereby effectively improving the gas analysis accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a flow chart of a data processing method of a Fourier infrared gas analyzer according to Embodiment 1 of the present invention;

[0035] Figure 2 1 is an air background spectrum and a zeroing spectrum diagram of Example 1 of the present invention;

[0036] Figure 3 is the air background spectrum and the zeroing spectrum after drift correction of Example 1 of the present invention;

[0037] Figure 4 It is a structural diagram of the data processing system of the Fourier infrared gas analyzer of Example 1 of the present invention. DETAILED DESCRIPTION

[0038] In order to more clearly illustrate the embodiments of the present invention, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other accompanying drawings and other implementation methods can be obtained based on these accompanying drawings without creative work.

[0039] Embodiment 1:

[0040] like Figure 1 As shown, the data processing method of the Fourier infrared gas analyzer of this embodiment includes the following steps:

[0041] (1) Collect the zeroing spectrum SPE0' by passing pure air into the air for zeroing;

[0042] like Figure 2 As shown in the figure, they are the air background spectrum SPE0 and the zeroing spectrum SPE0', respectively. The zeroing spectrum SPE0' has obvious drift, so it is necessary to perform drift correction on the Fourier infrared gas analyzer;

[0043] (2) Perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0' preset at the factory of the Fourier infrared gas analyzer to obtain the spectrum SPE 0_ and spectral SPE 0_ ';

[0044] Among them, the data volume increases several times after the spectrum is interpolated by Fourier, which effectively improves the calculation accuracy of the wavenumber drift;

[0045] (3) Select spectral SPE respectively 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k '; where the target band is the band corresponding to the water vapor absorption peak, k The values ​​are 1 and 2, representing two target bands respectively;

[0046] Specifically, as an example, the two target bands of this embodiment are 1700-1800 cm -1 and 3700~3800cm -1 ;

[0047] In this embodiment, four spectral segments are selected, namely, spectral segment SPE 0_ 1. Spectral SPE 0_ 1', Spectral SPE 0_ 2. Spectral SPE 0_ 2';

[0048] (4) SPE 0_ k 'Move left N After the wave number points and SPE 0_ k Calculate the matching degree and convert the spectrum segment SPE 0_ k 'Move left N -1 wave number point and SPE 0_ k Calculate the matching degree, and so on, and convert the spectrum segment SPE 0_ k 'Move left by 1 wave number point and then compare with SPE 0_ k Calculate the matching degree; then divide the spectrum segment SPE 0_ k 'Move right by one wave number point and then compare with SPE 0_ k Calculate the matching degree and convert the spectrum segment SPE 0_ k 'Move right 2 wave number points and SPE 0_ k Calculate the matching degree, and so on, and convert the spectrum segment SPE 0_ k 'Move right N After the wave number points and SPE 0_ k Calculate the matching degree; select the offset wavenumber point corresponding to the highest matching degree as the wavenumber drift, and obtain the wavenumber drift corresponding to the two target bands respectively. D k ; Among them, the wave number drift corresponding to the left shift is D k Take a negative value and shift the corresponding wave number drift to the right D k Take positive value, N is an integer greater than 1;

[0049] Specifically, as an example, the spectrum segment SPE 0_ 1' shifted 10 wave points to the left and then compared with SPE 0_ 1 Calculate the matching degree and convert the spectrum segment SPE 0_ 1' shifted 9 wave points to the left and then compared with SPE 0_ 1 Calculate the matching degree, and so on, the spectrum segment SPE 0_ 1' shifted left by 1 wave number point and SPE 0_ 1 Calculate the matching degree; then divide the spectrum segment SPE 0_ 1' shifted right by one wave number point and SPE 0_ 1 Calculate the matching degree and convert the spectrum segment SPE 0_1' shifted right by 2 wave number points and SPE 0_ 1 Calculate the matching degree, and so on, the spectrum segment SPE 0_ 1' shifted right by 10 wave number points and SPE 0_ 1. Calculate the matching degree; finally select the offset wave number point corresponding to the highest matching degree as the wave number drift D 1;

[0050] Specifically, as an example, the spectrum segment SPE 0_ 2' shifted 10 wave points to the left and then compared with SPE 0_ 2 Calculate the matching degree and convert the spectrum segment SPE 0_ 2' shifted 9 wave points to the left and then compared with SPE 0_ 2 Calculate the matching degree, and so on, the spectrum segment SPE 0_ 2' shifted left by one wave number point and SPE 0_ 2 Calculate the matching degree; then divide the spectrum segment SPE 0_ 2' shifted right by one wave number point and SPE 0_ 2 Calculate the matching degree and convert the spectrum segment SPE 0_ 2' shifted right by 2 wave number points and SPE 0_ 2 Calculate the matching degree, and so on, the spectrum segment SPE 0_ 2' shifted 10 wave points to the right and then compared with SPE 0_ 2 Calculate the matching degree; finally select the offset wave number point corresponding to the highest matching degree as the wave number drift D 2;

[0051] The above matching degree calculation can be performed using the least square method of the prior art;

[0052] (5) According to the wave number drift of the two target bands D k And the wave number average of the target band X k Calculate the spectral drift and proportional drift;

[0053] Specifically, the spectral shift of this embodiment is P for:

[0054] ;

[0055] The proportional drift of this embodiment Q for:

[0056] .

[0057] (6) Perform drift correction on the spectrum to be corrected based on the spectral drift and proportional drift.

[0058] Specifically, before drift correction is performed on the spectrum to be corrected, the spectrum to be corrected SPE conduct M Interpolate by multiples to get the interpolated spectrum SPE * .in, M The value is an integer multiple of 50; for example, M The value is 100.

[0059] The spectrum after drift correction in this embodiment is:

[0060] ;

[0061] in, i is the wave number, round is the rounding function.

[0062] like Figure 3 As shown, the zero spectrum after drift correction SPE New Keep consistent with the air background spectrum SPE0.

[0063] In addition, the data processing method of the Fourier infrared gas analyzer of this embodiment is used to analyze and detect methane CH4, nitric oxide NO, and carbon monoxide CO, and the gas concentrations obtained by drift correction without using the data processing method of this embodiment are compared. As shown in Table 1, after drift correction, the accuracy of gas measurement concentration is significantly improved.

[0064] Table 1 Comparison of gas concentrations before and after drift correction

[0065] .

[0066] Based on the above data processing method, this embodiment also provides a data processing system for a Fourier infrared gas analyzer, such as Figure 4 As shown, the following functional modules are included: an acquisition module, an interpolation module, a selection module, a calculation module and a correction module.

[0067] Specifically, the acquisition module of this embodiment is used to collect the zeroing spectrum SPE0' which is zeroed by passing pure air;

[0068] The interpolation module of this embodiment is used to perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0′ to obtain the spectrum SPE 0_ and spectral SPE 0_ ';

[0069] The selection module of this embodiment is used to select the spectrum SPE respectively. 0_ and spectral SPE 0_'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k ';

[0070] The calculation module of this embodiment is used to calculate the spectral segment SPE 0_ k 'After left or right shift and SPE 0_ k Calculate the matching degree;

[0071] The above selection module is also used to select the offset wave number point corresponding to the highest matching degree as the wave number drift, and obtain the wave number drift corresponding to the two target bands respectively. D k ;

[0072] The interpolation module is also used to perform drift correction on the spectrum to be corrected. SPE Perform interpolation;

[0073] The above calculation module is also used to calculate the wave number drift of the two target bands according to D k And the wave number average of the target band X k Calculate the spectral drift and proportional drift;

[0074] The correction module of this embodiment is used to perform drift correction on the spectrum to be corrected according to the spectral drift amount and the proportional drift amount.

[0075] The specific processing process of each of the above functional modules can be referred to the detailed description in the above data processing method, which will not be repeated here.

[0076] This embodiment also provides a readable medium, in which instructions are stored. When the instructions are executed on a computer, the computer executes the above data processing method to realize intelligent operation of drift correction.

[0077] Embodiment 2:

[0078] The data processing method of the Fourier infrared gas analyzer of this embodiment is different from that of Embodiment 1 in that:

[0079] The proportional drift of this embodiment Q for:

[0080] .

[0081] Accordingly, the spectrum after drift correction in this embodiment is:

[0082] ;

[0083] For other steps, please refer to Example 1;

[0084] In addition, the specific processing process of the corresponding functional modules of the data processing system of the Fourier infrared gas analyzer of this embodiment is adjusted accordingly;

[0085] The readable medium of this embodiment stores instructions. When the instructions are executed on a computer, the computer executes the data processing method of this embodiment and can also realize the intelligent operation of drift correction.

[0086] The above description is only a detailed description of the preferred embodiments and principles of the present invention. For ordinary technicians in this field, according to the ideas provided by the present invention, there will be changes in the specific implementation methods, and these changes should also be regarded as the protection scope of the present invention.

Claims

1. A data processing method for a Fourier infrared gas analyzer, characterized in that: The following steps are involved: S1, collecting the zeroing spectrum SPE0' by passing pure air into the air for zeroing; S2, respectively perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0' to obtain the spectrum SPE 0_ and spectral SPE 0_ '; S3, select the spectrum SPE respectively 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k'; where the target band is the band corresponding to the water vapor absorption peak, and the values ​​of k are 1 and 2, representing two target bands respectively; S4, spectrum segment SPE 0_ k' shifts N wave number points to the left and then SPE 0_ k calculates the matching degree and converts the spectrum segment SPE 0_ k' shifts N-1 wave number points to the left and then to SPE 0_ k calculates the matching degree, and so on, the spectrum segment SPE 0_ k' shifts left by one wave number point and SPE 0_ k calculates the matching degree; then the spectrum segment SPE 0_ k' shifts right by one wave number point and SPE 0_ k calculates the matching degree and converts the spectrum segment SPE 0_ k' shifts 2 wave number points to the right and SPE 0_ k calculates the matching degree, and so on, the spectrum segment SPE 0_ k' shifts right by N wave number points and SPE 0_ k calculates the matching degree; selects the offset wavenumber point corresponding to the highest matching degree as the wavenumber drift, and obtains the wavenumber drift D corresponding to the two target bands respectively k ; Among them, the wave number drift corresponding to the left shift is D k Take a negative value and shift the corresponding wave number drift D to the right k Take a positive value, N is an integer greater than 1; S5. According to the wave number drift D of the two target bands k And the wave number average value X of the target band k Calculate the spectral drift and proportional drift; S6, performing drift correction on the spectrum to be corrected according to the spectral drift amount and the proportional drift amount; In step S5, the spectral shift amount P is: ； The proportional drift Q is: ； In step S6, before drift correction is performed on the spectrum to be corrected, the spectrum to be corrected SPE is interpolated M times to obtain the interpolated spectrum SPE * ; In step S6, the spectrum after drift correction is: ； Where i is the wave number and round is the rounding function.

2. The data processing method according to claim 1, characterized in that: The value of M is an integer multiple of 50.

3. The data processing method according to claim 2, characterized in that: The value of M is 100.

4. The data processing method according to any one of claims 1 to 3, characterized in that: The two target bands are 1700-1800 cm -1 and 3700~3800cm -1 .

5. A data processing system for a Fourier infrared gas analyzer, using the data processing method according to claim 1, characterized in that: The data processing system comprises: A collection module, used for collecting a zeroing spectrum SPE0' which is zeroed by passing pure air; The interpolation module is used to perform Fourier interpolation on the air background spectrum SPE0 and the zero-adjusted spectrum SPE0' to obtain the spectrum SPE 0_ and spectral SPE 0_ '; Selection module, used to select spectra SPE separately 0_ and spectral SPE 0_ 'Spectral data in two target bands, get spectral segment SPE 0_ k and SPE 0_ k'; Computation module for spectral segment SPE 0_ k' left or right shift and SPE 0_ k calculates the matching degree; The selection module is also used to select the offset wave number point corresponding to the highest matching degree as the wave number drift, and obtain the wave number drift D corresponding to the two target bands respectively. k ; The calculation module is also used to calculate the wave number drift D of the two target bands according to the wave number drift D of the two target bands. k And the wave number average value X of the target band k Calculate the spectral drift and proportional drift; The correction module is used to perform drift correction on the spectrum to be corrected according to the spectral drift amount and the proportional drift amount.

6. A readable medium having instructions stored therein, characterized in that: When the instructions are executed on a computer, the computer is caused to execute the data processing method according to any one of claims 1 to 4.

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