A method for determining the carbon content of solid catalyst based on grayscale mode

Abstract

The invention discloses a method for measuring the carbon content of a solid catalyst based on a grayscale mode. First, a standard curve is established by using catalyst standard samples with different carbon content gradients and corresponding grayscale average values ​​to fix the carbon content of all gray standard color cards, and then the grayscale average values ​​of all gray standard color cards in each photo and the fixed carbon content are used to re-establish a standard curve of grayscale average values ​​and carbon content. Finally, the grayscale average value of the catalyst standard sample to be measured is substituted into the relationship equation of the newly established grayscale average value and the standard curve of carbon content to obtain the carbon content of the catalyst sample to be measured. When measuring the carbon content of the catalyst sample to be measured, it is no longer necessary to correct the ambient light, it is not disturbed by the ambient light, it is no longer limited to the same imaging device, and it has strong operability and good repeatability.

Description

Technical Field

[0001] The invention relates to the technical field of solid catalyst carbon content determination, and in particular to a method for determining the carbon content of a solid catalyst based on a grayscale mode. Background Art

[0002] In coal chemical industry, methanol to olefins, petrochemical industry, petroleum refining and other industries, catalysts will produce carbon deposits during the reaction process. The amount of carbon deposits in the catalyst is called the carbon content, and the amount of carbon content will directly affect the catalytic performance of the catalyst. Therefore, how to measure the carbon content of the catalyst in a timely, rapid and accurate manner during the production process is of great significance for guiding production, process control and process operation optimization.

[0003] For example, a Chinese patent application with application publication number CN105510244A and application publication date April 2, 2016 discloses a method for rapidly detecting the carbon deposit content of a solid catalyst using a colorimetric analysis method, which uses a mixture of carbon powder and a catalyst to simulate the color state of a carbon-deposited catalyst; uses a color imaging device to collect the color of a catalyst containing carbon powder of different masses; and compares the color with the color of the solid catalyst to be tested to determine the carbon deposit content in the solid catalyst to be tested. This detection method has the following defects: (1) The carbon deposit catalyst sample made by mixing carbon powder of different masses is quite different from the actual catalyst sample. The actual catalyst will appear gray, yellow-green, dark green, etc. after carbon deposition, resulting in a large error in the analysis result; (2) The measurement is easily affected by the external ambient light source, resulting in a deviation in the color of the catalyst photographed, affecting the accuracy of the result. Summary of the invention

[0004] The present invention aims to solve the above-mentioned problems existing in the method of rapid detection of solid catalyst carbon content by colorimetric analysis in the prior art, and provides a method for determining the carbon content of solid catalyst based on grayscale mode, which is easy to operate, not affected by external light sources, has good repeatability and high accuracy.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme: A method for determining the carbon content of a solid catalyst based on a grayscale mode of the present invention comprises the following steps:

[0006] (1) Take a plurality of gray standard color cards with different grayscale average values ​​and a plurality of catalyst standard samples with different known carbon content gradients, and use an imaging device to take a photo of all the catalyst standard samples and all the gray standard color cards in the same frame. Try to keep it horizontal when taking photos. In the present invention, when taking photos, it is also possible to directly obtain photos in grayscale mode, so that there is no need to adjust the photo mode from RGB color mode to grayscale mode in the subsequent process; the catalyst standard samples here are the same catalyst, and different types of catalyst standard samples need to be photographed separately.

[0007] (2) The mode of the obtained photo is adjusted from RGB color mode to grayscale mode through image processing software, and the grayscale average value of all gray standard color cards and the grayscale average value of all catalyst standard samples in the photo are obtained through image processing software. If PS software is used, a rectangular selection tool is used to select an area, and the grayscale average value can be directly displayed through the histogram.

[0008] (3) Based on the grayscale average values ​​and carbon contents of all catalyst standard samples, a curve is drawn with the carbon content as the ordinate and the grayscale average values ​​of all catalyst standard samples as the abscissa to obtain a relationship equation of the standard curve between the grayscale average values ​​of the catalyst standard samples and the carbon content.

[0009] (4) Substitute the grayscale average values ​​of all gray standard color cards into the relationship equation of the grayscale average value of the catalyst standard sample and the standard curve of the carbon content to obtain the carbon content corresponding to all gray standard color cards.

[0010] (5) All gray standard color cards and the catalyst sample to be tested are photographed in the same frame, and the mode of the obtained photo is adjusted from RGB color mode to grayscale mode through image processing software, and the grayscale average value of all gray standard color cards and the grayscale average value of the catalyst sample to be tested in the photo are obtained through image processing software. If the grayscale mode photo can be directly obtained, there is no need to adjust the mode of the photo from RGB color mode to grayscale mode.

[0011] (6) Based on the grayscale average values ​​corresponding to all the gray standard color cards obtained in step (5) and the carbon contents corresponding to all the gray standard color cards in step (4), a new standard curve is drawn and established with the carbon content of the gray standard color cards as the ordinate and the grayscale average values ​​of the gray standard color cards as the abscissa, and a relationship equation of the standard curve between the grayscale average values ​​of the gray standard color cards and the carbon content of the gray standard color cards is obtained.

[0012] (7) Substituting the grayscale average value of the catalyst sample to be tested in step (5) into the relationship equation of the standard curve of the grayscale average value of the gray standard color card and the carbon content of the gray standard color card in step (6); the carbon content obtained by calculation is the carbon content of the catalyst sample to be tested.

[0013] Preferably, in step (1), there are at least 5 gray standard color cards.

[0014] Preferably, in step (1), the imaging device is a mobile phone with a camera function, a camera, a camcorder or a scanner.

[0015] Preferably, in step (2), the image processing software is PS software. PS software is commonly used, and the specific version is not limited, as long as it can achieve the above functions, and other image processing software with the above functions or various application software developed for the above method can also be used.

[0016] Preferably, in step (2), the photo is adjusted from RGB color mode to 16-bit grayscale mode.

[0017] Therefore, the present invention has the following beneficial effects: the present invention first uses catalyst standard samples with different carbon content gradients and corresponding grayscale average values ​​to establish a standard curve to calibrate the carbon content of all gray standard color cards, and then uses the grayscale average values ​​of all gray standard color cards in each photo and the calibrated carbon content to re-establish the standard curve of grayscale average value and carbon content, and finally substitutes the grayscale average value of the catalyst standard sample to be tested into the relationship equation of the newly established grayscale average value and the standard curve of carbon content to obtain the carbon content of the catalyst sample to be tested. In this way, when measuring the carbon content of the catalyst sample to be tested, there is no need to correct the ambient light, it is not affected by the ambient light, it is no longer limited to the same imaging device, and it has strong operability and good repeatability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 There are 8 gray standard color cards and 6 photos of catalyst standard samples with different carbon content gradients (RGB mode).

[0019] Figure 2 There are 8 gray standard color cards and 6 photos of catalyst standard samples with different carbon content gradients (grayscale mode).

[0020] Figure 3 It is a standard curve diagram of the grayscale average value and carbon content of all catalyst standard samples in step (3).

[0021] Figure 4 These are the 8 gray standard color cards and the photos of the catalyst samples to be tested (RGB mode) in step (5).

[0022] Figure 5 These are the 8 gray standard color cards and the photos of the catalyst samples to be tested (grayscale mode) in step (5).

[0023] Figure 6 It is a standard curve diagram of the grayscale average value of the 8 gray standard color cards in step (6) and its corresponding carbon content. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0025] Example

[0026] (1) Take 8 gray standard color cards with different grayscale average values ​​and 7 (same) catalyst standard samples with different known carbon content gradients, and use imaging equipment to take photos of all catalyst standard samples and all gray standard color cards in the same frame. The obtained photos are as follows Figure 1 As shown; the catalyst standard sample is a methanol to olefins catalyst, which comes from a sample collected from the MTO reactor of the methanol to olefins unit of Tianjin Bohai Chemical Development Co., Ltd. The carbon content is shown in Table 1.

[0027] (2) Using PS software (Adobe Photoshop CC 2017), the mode of the obtained photo was adjusted from RGB color mode to 16-bit grayscale mode (such as Figure 2 The grayscale average values ​​of all gray standard color cards and the grayscale average values ​​of all catalyst standard samples in the photo were obtained by using PS software (a region was selected using a rectangular selection tool, and the grayscale average value was displayed through a histogram). The grayscale average values ​​of all gray standard color cards and the grayscale average values ​​of all catalyst standard samples are shown in Table 1.

[0028] (3) Based on the grayscale average value and carbon content of all catalyst standard samples, a curve is drawn with carbon content as the ordinate and the grayscale average value of all catalyst standard samples as the abscissa (e.g. Figure 3 As shown in the figure), the relationship equation between the gray value of the catalyst standard sample and the standard curve of carbon content is obtained (y = 13.6877e -0.0116x ).

[0029] (4) Substitute the grayscale average values ​​of all gray standard color cards into the relationship equation of the grayscale average value of the catalyst standard sample and the standard curve of the carbon content to obtain the carbon content corresponding to all gray standard color cards (as shown in Table 1).

[0030] Table 1 Carbon content and grayscale average of 6 catalyst standard samples and grayscale average of 8 gray standard color cards with different grayscale averages and their corresponding carbon content

[0031]

[0032]

[0033] (5) Take a photo of all the gray standard color cards and the catalyst sample to be tested in the same frame (such as Figure 4 As shown), the catalyst sample to be tested and the catalyst standard sample are the same catalyst, the carbon content is unknown, and the mode of the obtained photo is adjusted from RGB color mode to grayscale mode (as shown in Figure 5The grayscale average value of all gray standard color cards in the photo and the grayscale average value of the catalyst sample to be tested (50.32) were obtained by PS software.

[0034] (6) Based on the grayscale average values ​​corresponding to all gray standard color cards obtained in step (5) and the carbon content corresponding to all gray standard color cards obtained in step (4), a new standard curve is drawn and established with the carbon content of the gray standard color cards as the ordinate and the grayscale average value of the gray standard color cards as the abscissa (e.g. Figure 6 As shown), the relationship equation between the grayscale average value of the gray standard color card and the standard curve of the carbon content of the gray standard color card is obtained (y = 12.3723e -0.0113x ).

[0035] (7) Substituting the grayscale average value of the catalyst sample to be tested in step (5) into the relationship equation of the standard curve of the grayscale average value of the gray standard color card and the carbon content of the gray standard color card in step (6); the carbon content is calculated to be 7.007%, that is, the carbon content of the catalyst sample to be tested is 7.007%.

[0036] The carbon content of the catalyst sample measured by thermogravimetric method (existing technology) is 7.112%.

[0037] The absolute error of the carbon content measured by the two methods is 0.105%, the relative error is 1.48%, and the standard deviation of the carbon deposit distribution is 14.86, which shows that the accuracy of the present invention is relatively high.

[0038] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A method for determining the carbon content of a solid catalyst based on a grayscale mode, It is characterized in that The following steps are involved: (1) Take a plurality of gray standard color cards with different grayscale average values ​​and a plurality of catalyst standard samples with different known carbon content gradients, and use an imaging device to take photos of all the catalyst standard samples and all the gray standard color cards in the same frame; (2) adjusting the mode of the obtained photo from the RGB color mode to the grayscale mode through the image processing software, and obtaining the grayscale average value of all gray standard color cards and the grayscale average value of all catalyst standard samples in the photo through the image processing software; (3) Based on the grayscale average values ​​and carbon contents of all catalyst standard samples, a curve is drawn with the carbon content as the ordinate and the grayscale average values ​​of all catalyst standard samples as the abscissa to obtain a relationship equation of the standard curve between the grayscale average values ​​of the catalyst standard samples and the carbon content; (4) Substituting the grayscale average values ​​of all gray standard color cards into the relationship equation of the grayscale average value of the catalyst standard sample and the standard curve of carbon content, the carbon content corresponding to all gray standard color cards is obtained; (5) taking a photo of all the gray standard color cards and the catalyst sample to be tested in the same frame, adjusting the mode of the obtained photo from the RGB color mode to the grayscale mode through image processing software, and obtaining the grayscale average value of all the gray standard color cards in the photo and the grayscale average value of the catalyst sample to be tested through the image processing software; (6) Based on the grayscale average values ​​corresponding to all gray standard color cards obtained in step (5) and the carbon contents corresponding to all gray standard color cards obtained in step (4), a new standard curve is drawn with the carbon content of the gray standard color cards as the ordinate and the grayscale average value of the gray standard color cards as the abscissa, to obtain a relationship equation between the grayscale average value of the gray standard color cards and the carbon content of the gray standard color cards; (7) Substituting the grayscale average value of the catalyst sample to be tested in step (5) into the relationship equation of the standard curve of the grayscale average value of the gray standard color card and the carbon content of the gray standard color card in step (6); the carbon content obtained by calculation is the carbon content of the catalyst sample to be tested.

2. The method for determining the carbon content of a solid catalyst based on a grayscale mode according to claim 1, It is characterized in that In step (1), the number of gray standard color cards is at least 5.

3. The method for determining the carbon content of a solid catalyst based on a grayscale mode according to claim 1, It is characterized in that In step (1), the imaging device is a mobile phone with a camera function, a camera, a webcam or a scanner.

4. The method for determining the carbon content of a solid catalyst based on a grayscale mode according to claim 1, It is characterized in that In step (2), the image processing software is PS software.

5. The method for determining the carbon content of a solid catalyst based on a grayscale mode according to claim 1, It is characterized in that In step (2), the photo is adjusted from RGB color mode to 16-bit grayscale mode.

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