Data processing method and system of water quality analyzer and readable storage medium

Abstract

The invention belongs to the technical field of analysis and detection, and relates to a data processing method and system of a water quality analyzer and a readable storage medium. The water quality analyzer comprises a light source, a first lens, an optical filter, a dichroic spectroscope, a measuring cell, a second lens, an aperture diaphragm and a detector which are sequentially arranged in the light path direction; a reference light beam reflected by the dichroic spectroscope is converged by a third lens and enters a reference detector; the data processing method comprises the steps that the energy value of each pixel point of a reference detector is collected, an energy peak value is searched, a first pixel point with the energy value not larger than half of the energy peak value is searched from the energy peak value to the two sides, and a pixel point X1 and a pixel point X2 are obtained; according to the pixel X1, the pixel X2 and the reference light path length, calculating to obtain a light source emission angle; the incident light intensity is corrected according to the environment temperature and the light source emission angle, the corrected incident light intensity is obtained, and the absorbance is calculated according to the corrected incident light intensity. The analysis precision of the water quality analyzer is effectively improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of analytical detection, and particularly relates to a data processing method and system of a water quality analyzer and a readable storage medium. BACKGROUND

[0002] Most existing water quality analyzers adopt the principle of spectrophotometry and are based on the Lambert-Beer law for quantitative analysis. However, in actual application, this method is easily affected by environmental temperature, stray light, scattering or reflection caused by non-uniform to-be-measured solution and many other interferences, resulting in poor stability and accuracy of the equipment. Among them, the most important influencing factor is the influence of environmental temperature. When the environmental temperature changes, it will cause a slight structural deformation, affect the light source emission angle change, the light source energy size, the to-be-measured solution temperature and the like, and further affect the measurement value. SUMMARY

[0003] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the purposes of the present application is to at least solve one or more of the above-mentioned problems in the prior art, in other words, one of the purposes of the present application is to provide a data processing method, system and readable storage medium of a water quality analyzer which satisfy one or more of the aforementioned needs.

[0004] In order to achieve the above-mentioned purposes of the application, the following technical solutions are adopted: A data processing method of a water quality analyzer, the water quality analyzer comprising a light source, a first lens, a filter, a dichroic beam splitter, a measuring cell, a second lens, an aperture diaphragm and a detector which are sequentially arranged along a detection light path direction, reference light beams obtained by reflecting the light emitted by the light source through the first lens, the filter and the dichroic beam splitter are converged into a reference detector through a third lens to form a reference light path, and the reference detector is connected with a light source modulator signal of the light source; The data processing method comprises the following steps: S1, collecting the energy value of each pixel point of the reference detector, searching for an energy peak I f and searching for the first pixel point with an energy value I≤I f / 2 from both sides of the energy peak I f , to obtain a pixel point X1 and a pixel point X2; S2, calculating the light source emission angle according to the pixel point X1, the pixel point X2 and the reference light path length; S3, correcting the incident light intensity according to the environmental temperature and the light source emission angle to obtain the corrected incident light intensity, and calculating the absorbance according to the corrected incident light intensity.

[0005] As a preferred scheme, in the step S2, the light source emission angle θ is: ; Wherein, L is the reference light path length, L=L1+L2, L1 is the distance between the light source and the dichroic mirror, and L2 is the distance between the dichroic mirror and the reference detector.

[0006] As a preferred solution, the reference detector is a CMOS linear array detector.

[0007] As a preferred solution, in the step S3, the corrected incident light intensity is: ; Wherein, k1 and b are fitting coefficients, T is the ambient temperature, and θ is the light source emission angle, is the incident light intensity.

[0008] As a preferred solution, the light source emission angle is not greater than 20°.

[0009] As a preferred solution, in the step S3, the absorbance A is: ; Wherein, I t is the transmitted light intensity.

[0010] As a preferred solution, the step S3 further comprises: According to the temperature of the water sample to be analyzed in the measuring cell and the working temperature of the detector, the transmitted light intensity of the water sample to be analyzed is corrected to obtain a corrected transmitted light intensity; and then the corrected incident light intensity and the corrected transmitted light intensity are used to calculate the absorbance.

[0011] As a preferred solution, the corrected transmitted light intensity is: ; Wherein, k2, k3 and k4 are fitting coefficients, t1 is the temperature of the water sample to be analyzed, t2 is the working temperature of the detector, and I t is the transmitted light intensity of the water sample to be analyzed.

[0012] The application also provides a data processing system of a water quality analyzer, which applies the data processing method according to any one of the above solutions, and the data processing system comprises: A collection module, configured to collect the energy value of each pixel point of the reference detector; A search module, configured to search for an energy peak I f and search for the first pixel point with an energy value I≤I f from both sides of the energy peak I f to obtain a pixel point X1 and a pixel point X2; A calculation module, configured to calculate the light source emission angle according to the pixel point X1, the pixel point X2 and the reference light path length. A correction module is configured to correct the incident light intensity according to the ambient temperature and the light source emission angle to obtain a corrected incident light intensity. The calculation module is further configured to calculate the absorbance according to the corrected incident light intensity.

[0013] The application further provides a readable storage medium, wherein instructions are stored in the readable storage medium, and when the instructions are executed on a computer, the computer executes the data processing method according to any one of the above solutions.

[0014] Compared with the prior art, the application has the following beneficial effects: (1) The application can collect the energy value of each pixel point of the reference detector in real time based on the change of the light source emission angle, and obtain the real-time light source emission angle, and then correct the incident light intensity according to the ambient temperature and the light source emission angle, so as to effectively improve the calculation accuracy of the absorbance and improve the analysis accuracy of the water quality analyzer. (2) The application can accurately calculate the divergence angle of the light spot, i.e., the light source emission angle, according to the energy distribution of the light spot on the reference detector. (3) The application can correct the transmitted light intensity according to the temperature of the water sample to be analyzed in the measuring pool and the working temperature of the detector, so as to further improve the calculation accuracy of the absorbance and further improve the analysis accuracy of the water quality analyzer. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 FIG. 1 is a structural diagram of a water quality analyzer according to Embodiment 1 of the application; Figure 2 FIG. 2 is a module composition diagram of a data processing system of the water quality analyzer according to Embodiment 1 of the application; Figure 3 FIG. 3 is a comparison diagram of the linear relationship between the absorbance obtained by the data processing method according to Embodiment 1 of the application and the standard solution concentration and the linear relationship between the absorbance obtained by the data processing method according to Comparative Example 1 and the standard solution concentration; Figure 4 FIG. 4 is a comparison diagram of the concentration (corrected) obtained by the data processing method according to Embodiment 1 of the application and the concentration (uncorrected) obtained by the data processing method according to Comparative Example 1; Figure 5 FIG. 5 is a pixel point and light intensity distribution diagram collected by the reference detector according to a specific application example of the application. DETAILED DESCRIPTION

[0016] In order to more clearly illustrate the embodiments of the application, the specific embodiments of the application will be described below with reference to the drawings. Obviously, the drawings in the following description are only some embodiments of the application, and those skilled in the art can obtain other drawings and other embodiments according to these drawings without creating any creative labor.

[0017] Embodiment 1: As Figure 1 shown, the water quality analyzer of the embodiment comprises, in sequence along the direction of the detection light path, a light source 1, a first lens 2, a filter 3, a dichroic beam splitter 4, a measuring cell 5, a second lens 6, an aperture stop 7, and a detector 8, and further comprises a light source modulator 9, a third lens 10, and a reference detector 11; The light emitted by the light source 1 passes through the first lens 2 and the filter 3, and the reference light beam obtained by reflection of the light through the dichroic beam splitter 4 passes through the third lens 10 to converge into the reference detector 11 to form a reference light path, and the reference detector 11 is signal-connected to the light source modulator 9 of the light source 1 through an existing reference system 12 of the water quality analyzer.

[0018] Before the water quality analysis starts, the homogeneity of the water sample to be analyzed is first judged, and the specific process is as follows: first, the absorption light intensity of the water sample to be analyzed is measured, and then compared with the absorption light intensity of the zero sample; if the ratio of the absorption light intensity of the water sample to be analyzed to the absorption light intensity of the zero sample is ≥0.98, it indicates that the homogeneity of the water sample to be analyzed is good, otherwise, the double-wavelength interference deduction or pretreatment method is used to reduce the interference of the sample itself. In addition, if the ratio of the absorption light intensity of the mixture of the zero sample and the analysis reagent to the absorption light intensity of the zero sample is ≥0.98, it indicates that the background absorption of the analysis reagent is very small and basically does not affect the Lambert-Beer law, otherwise, it indicates that the absorption of the analysis reagent itself is large and cannot be ignored, and the double-wavelength interference deduction method is used. The double-wavelength interference deduction and the pretreatment method can refer to the existing technology, and will not be described here.

[0019] The data processing method of the water quality analyzer comprises the following steps: (1) Collect the energy value of each pixel point of the reference detector, search for the energy peak I f , and search for the first pixel point with an energy value I≤I f / 2 from the energy peak I f , to obtain the pixel point X1 and the pixel point X2. The reference detector of the embodiment is a CMOS linear array detector, the pixel unit size is 25*500 μm, there are 512 pixel points, and the detection area is 12.8*0.5 mm; according to the energy distribution of the light spot on the reference detector, the divergence angle of the light spot, i.e. the emission angle of the light source, can be calculated. After the energy peak I f is found, the first pixel point with an energy value I≤I f / 2 is searched to the left and right, so as to determine the pixel point X1 and the pixel point X2.

[0020] (2) Calculate the emission angle θ of the light source according to the pixel point X1, the pixel point X2, and the reference light path length L; Specifically, the emission angle θ of the light source is: ; Wherein, L is a reference light path length, L = L1 + L2, L1 is the distance between the light source and the dichroic mirror, L2 is the distance between the dichroic mirror and the reference detector, and the specific as Figure 1 shown.

[0021] Wherein, the smaller the angle of the light source emission angle, the greater the brightness; the greater the angle, the smaller the brightness; therefore, the light source emission angle of the embodiment is preferably not greater than 20°.

[0022] (3) According to the ambient temperature, the light source emission angle, the incident light intensity is corrected to obtain the corrected incident light intensity; According to the temperature of the water sample to be analyzed in the measuring cell and the working temperature of the detector, the transmission light intensity of the water sample to be analyzed is corrected to obtain the corrected transmission light intensity; Finally, the absorbance is calculated according to the corrected incident light intensity and the corrected transmission light intensity, and the component concentration of the water sample to be analyzed is calculated according to the absorbance; The corrected incident light intensity of the embodiment is : ; Wherein, k1 and b are fitting coefficients, T is the ambient temperature, θ is the light source emission angle, is the incident light intensity.

[0023] The corrected transmission light intensity of the embodiment is : ; Wherein, k2, k3 and k4 are fitting coefficients, t1 is the temperature of the water sample to be analyzed, t2 is the working temperature of the detector, I t is the transmission light intensity of the water sample to be analyzed.

[0024] The absorbance A of the embodiment is ; Wherein, the component concentration of the water sample to be analyzed calculated according to the absorbance belongs to the prior art, which is not described here.

[0025] Based on the above data processing method, the embodiment also provides a corresponding data processing system of the water quality analyzer, as shown in Figure 2 shown, comprising the following functional modules: acquisition module, search module, calculation module and correction module; The above acquisition module is used for acquiring the energy value of each pixel point of the reference detector; The above search module is used for searching the energy peak I f and searching the energy value I≤I f from both sides of the energy peak I fthe first pixel point of the second image, to obtain the pixel point X1 and the pixel point X2; The calculation module is configured to calculate the light source emitting angle according to the pixel point X1, the pixel point X2 and the reference light path length; The correction module is configured to correct the incident light intensity according to the ambient temperature and the light source emitting angle to obtain the corrected incident light intensity, and correct the transmission light intensity of the water sample to be analyzed according to the temperature of the water sample to be analyzed in the measuring cell and the working temperature of the detector to obtain the corrected transmission light intensity. The calculation module is further configured to calculate the absorbance according to the corrected incident light intensity and the corrected transmission light intensity.

[0026] The embodiment also provides a readable storage medium, and the readable storage medium stores instructions. When the instructions run on a computer, the computer executes the data processing method described above in the embodiment, and realizes intelligent data processing.

[0027] Comparative Example 1: The data processing method of the water quality analyzer in the comparative example is different from that in the embodiment 1 in that: The absorbance is obtained by directly taking the logarithm of the ratio of the uncorrected incident light intensity to the uncorrected transmission light intensity.

[0028] The data processing methods of the embodiment 1 and the comparative example 1 are compared and verified as follows: The ammonia nitrogen standard solution is used as the standard solution, and the ammonia nitrogen standard solution with different standard solution concentrations is analyzed and detected, and the results are shown in Table 1. Table 1: Absorbance of ammonia nitrogen standard solution with different concentrations ; A linear graph of the absorbance and the standard solution concentration is drawn according to the absorbance data in Table 1, as shown in Figure 3 The data processing method of the embodiment 1 obtains the linear best absorbance, and the R 2 reaches 0.9999, which is obviously better than the data processing method of the comparative example 1.

[0029] Further, the data processing method of the embodiment 1 is used for long-term measurement of 1.5mg / L standard solution, as shown in Figure 4 The comparison of the absorbance changes of the data processing method of the embodiment 1 and the data processing method of the comparative example 1 shows that the stability of the absorbance obtained by the data processing method of the embodiment 1 is obviously better than that of the comparative example 1, and the accuracy of the data is also closer to the theoretical value.

[0030] In addition, the data processing method of the embodiment 1 is applied to a specific application example for detecting an ammonia nitrogen standard sample with a concentration of 8mg / L, and the specific process is as follows: First, the energy value of each pixel of the reference detector is collected, i.e., the light intensity distribution is as follows: Figure 5 As shown, the search energy peak I f Given 20491, search for energy values ​​I≤I on both sides. f The first pixel of / 2 is obtained as pixel X1 = 212 and pixel X2 = 337; Then, the emission angle of the light source is calculated based on pixel X1, pixel X2 and the reference optical path length L; specifically, the reference optical path length L = 110 mm; ; Next, the incident light intensity was corrected based on the ambient temperature T = 28.086℃ and the emission angle θ of the light source, resulting in the corrected incident light intensity: ; The transmitted light intensity of the water sample to be analyzed is also corrected based on the temperature of the water sample in the measuring cell and the operating temperature of the detector, resulting in the corrected transmitted light intensity: ; Finally, the absorbance was calculated as follows: This translates to an ammonia nitrogen concentration of 7.954 mg / L.

[0031] The absorbance obtained using the data processing method in Comparative Example 1 is: This translates to an ammonia nitrogen concentration of 8.655 mg / L.

[0032] Therefore, the data processing method of this invention can effectively improve the analytical accuracy of water quality analyzers.

[0033] The above description is merely a detailed explanation of preferred embodiments and principles of the present invention. For those skilled in the art, there may be changes in specific implementation methods based on the ideas provided by the present invention, and these changes should also be considered within the scope of protection of the present invention.

Claims

1. A data processing method of a water quality analyzer, characterized by, The water quality analyzer comprises, in sequence along a detection light path direction, a light source, a first lens, a filter, a dichroic beam splitter, a measuring cell, a second lens, an aperture stop and a detector; the light emitted by the light source passes through the first lens and the filter, and a reference light beam obtained by reflection of the dichroic beam splitter passes through a third lens to converge into a reference detector to form a reference light path; the reference detector is connected with a light source modulator signal of the light source; The data processing method comprises the following steps: S1, collect the energy value of each pixel point of the reference detector, search for the energy peak I f And from the energy peak I f The first pixel point with energy value I≤I f / 2, get the pixel point X1 and the pixel point X2; S2, calculating a light source emission angle according to the pixel point X1, the pixel point X2 and the reference light path length; S3, correcting an incident light intensity according to the ambient temperature and the light source emission angle to obtain a corrected incident light intensity, and calculating an absorbance according to the corrected incident light intensity.

2. The data processing method according to claim 1, characterized in that, In the step S2, the light source emission angle θ is: ； Wherein, L is the reference light path length, L=L1+L2, L1 is the distance between the light source and the dichroic beam splitter, and L2 is the distance between the dichroic beam splitter and the reference detector.

3. The data processing method of claim 1, wherein, The reference detector is a CMOS linear array detector.

4. The data processing method of claim 1, wherein, In the step S3, the modified incident light intensity is: ； Wherein, k1, b are fitting coefficients, T is the ambient temperature, θ is the light source emission angle, is the incident light intensity.

5. The data processing method according to claim 4, characterized in that, The light source emission angle is not greater than 20°.

6. The data processing method according to any one of claims 1 to 5, characterized in that, In the step S3, the absorbance A is: ； where I t is the transmitted light intensity.

7. The data processing method according to claim 6, characterized in that, The step S3 further comprises: Correcting a transmitted light intensity of the water sample to be analyzed according to the temperature of the water sample to be analyzed in the measuring cell and the working temperature of the detector to obtain a corrected transmitted light intensity, and then calculating the absorbance according to the corrected incident light intensity and the corrected transmitted light intensity.

8. The data processing method according to claim 7, characterized in that, the modified transmitted light intensity is: ； wherein k2, k3, k4 are fitting coefficients, t1 is the temperature of the water sample to be analyzed, t2 is the working temperature of the detector, I t is the transmitted light intensity of the water sample to be analyzed.

9. A data processing system of a water quality analyzer, which applies the data processing method according to any one of claims 1 to 8, characterized in that, The data processing system comprises: An acquisition module for acquiring an energy value of each pixel point of the reference detector; a search module for searching for the energy peak I f and searching for the first pixel point with energy value I≤I f from the energy peak I f , obtaining pixel point X1 and pixel point X2; A calculation module for calculating a light source emission angle according to the pixel point X1, the pixel point X2 and the reference light path length; A correction module for correcting an incident light intensity according to the ambient temperature and the light source emission angle to obtain a corrected incident light intensity; The calculation module is further used for calculating an absorbance according to the corrected incident light intensity.

10. A readable storage medium, having stored therein instructions, characterized in that, When the instructions are run on the computer, the computer executes the data processing method according to any one of claims 1-8.

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