A slag melting performance evaluation method and evaluation system
By binarizing the images of the slag at the initial stage and during the heating process and calculating the area change rate, the problem of simple evaluation methods in the existing technology is solved, and a comprehensive and accurate evaluation of the slag melting performance is achieved.
Patent Information
- Application Number
- CN202210384382.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-04-13
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2042-04-13
AI Technical Summary
The existing evaluation method for slag melting performance is too simple. It only uses three indicators, namely the starting melting temperature, melting temperature and fluidity temperature, and cannot fully reflect the details of the melting process.
The initial area is calculated by acquiring images at the initial temperature of the slag and performing binarization processing. The real-time area is calculated by continuously acquiring images during the heating and melting process and performing binarization processing. The area change rate is used to evaluate the slag melting performance.
A comprehensive evaluation of the slag melting process is achieved, the accuracy of the melting performance evaluation is improved, and the details of the melting process can be better reflected.
Smart Images
Figure CN114998188B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of metallurgy, and in particular to a slag melting performance evaluation method and evaluation system. Background Art
[0002] Various slags are used in metallurgical production, including blast furnace slag, hot metal pretreatment slag, steelmaking slag, and mold slag used in continuous casting. Different slags have varying properties and serve different purposes. Slag melting properties are a key indicator for evaluating slag's high-temperature performance, impacting the smooth progress of the process and the quality of the product. Therefore, slag melting properties are crucial for processes such as ironmaking, hot metal pretreatment, steelmaking, and continuous casting.
[0003] At present, the evaluation method of slag melting performance consists of three indicators, namely the starting melting temperature, melting temperature and fluidity temperature. Specifically, the slag is ground into powder and pressed into a columnar sample with a diameter of 3mm and a height of 3mm, such as Figure 2 (a) As shown. During the heating process, when the sample height drops to 75% of the original height (H), the temperature at this time is defined as the melting temperature, as shown in Figure 2 (b) As shown; continue to increase the temperature, when the sample height drops to 50% of the original height, the sample becomes hemispherical. The temperature at this time is defined as the melting temperature, sometimes also called the hemispherical point temperature, such as Figure 2 As shown in (c); as the temperature continues to rise, when the sample height decreases to 25% of the original height, the sample is completely melted, and the temperature at this time is defined as the fluidity temperature of the slag, as shown in Figure 2 (d) shown.
[0004] However, during the melting process of the slag, as the temperature rises, the upper surface may not completely follow the Figure 1 The changes in the middle are not so regular, and the upper side becomes a zigzag shape, such as Figure 3 As shown in (b), the exact point representing the height is questionable. Traditional slag evaluation methods typically use a single point to represent the overall slag's melting properties, which is somewhat one-sided. Furthermore, the evaluation metrics are overly simplistic, yielding only three indicators: the onset melting temperature, the melting temperature, and the fluidity temperature. These are all post-shrinkage indicators, but the details of the melting process are not captured. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a method for evaluating the melting performance of slag, which can solve the problem that the evaluation indicators are too simple and only three indicators, namely the starting melting temperature, the melting temperature and the fluidity temperature, are obtained. All of them are indicators after shrinkage, and the details of the melting process are not reflected.
[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:
[0007] In one aspect, a method for evaluating slag melting performance is provided, the method comprising:
[0008] Acquire an image at the initial temperature of the slag;
[0009] Performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature;
[0010] Acquire images at any time during the slag heating and melting process;
[0011] Binarizing the image at any time during the slag heating and melting process to obtain the real-time area of the slag during the heating and melting process;
[0012] Obtaining an area change rate according to the real-time area and the initial area;
[0013] The slag melting performance is evaluated based on the area change rate.
[0014] In an optional embodiment, performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature includes:
[0015] The binarized image of the initial temperature is divided into a plurality of square grid units, and the sum of the image areas of the initial temperature in all the square grid units is taken as the initial area.
[0016] In an optional embodiment, the area when the area of the square grid unit tends to be infinitely small is used as a pixel point, and the number of pixel points in the initial temperature image is counted as the initial area.
[0017] In an optional embodiment, counting the number of pixels in the image of the initial temperature as the initial area includes:
[0018] Obtaining a pixel value of an image pixel point of the initial temperature in the square grid unit, and setting the pixel value to 0 when the pixel value is less than a first threshold value, and setting the pixel value to 255 when the pixel value is greater than or equal to the first threshold value;
[0019] The number of pixel points whose pixel value is equal to 255 is obtained, and the number of image pixel points whose initial temperature is equal to 255 is used as the initial area.
[0020] In an optional embodiment, the initial area is obtained according to the following formula:
[0021] S0=ΣF0(x i ,y j), i = 0 ~ W + 1; j = 0 ~ H + 1
[0022] Where:
[0023] S0 is the initial area;
[0024] W is the number of pixels in the width direction of the square grid unit;
[0025] H is the number of pixels in the height direction of the square grid unit;
[0026] F0(x i ,y j ) is the pixel point with a pixel value of 255 in the image of the initial temperature, x i is the width coordinate of the square grid unit, y j is the height coordinate in the square grid unit.
[0027] In an optional embodiment, binarization processing is performed on the image at any time during the slag heating and melting process to obtain the real-time area during the slag heating and melting process, including:
[0028] The binarized image at any time is divided into a plurality of square grid units, and the sum of the image areas at any time in all the square grid units is used as the real-time area.
[0029] In an optional embodiment, when the image area at any moment in the square grid unit tends to be infinitely small, the number of pixels in the image at any moment is counted as the real-time area.
[0030] In an optional embodiment, counting the number of pixels in the image at any time as the real-time area includes:
[0031] Obtaining a pixel value of a pixel point in the image at any moment in the square grid unit, and setting the pixel value to 0 when the pixel value is less than a second threshold value, and setting the pixel value to 255 when the pixel value is greater than or equal to the second threshold value;
[0032] The number of pixel points whose pixel value is equal to 255 is obtained, and the number of image pixel points equal to 255 at any moment is used as the real-time area.
[0033] In an optional embodiment, the real-time area is obtained according to the following formula:
[0034] S1=ΣF1(x i ,y j ), i = 0 ~ W + 1; j = 0 ~ H + 1
[0035] Where:
[0036] S1 is the real-time area;
[0037] W is the number of pixels in the width direction of the square grid unit;
[0038] H is the number of pixels in the height direction of the square grid unit;
[0039] F1(x i ,y j ) is the pixel point with a pixel value equal to 255 in the square grid unit at any time, x i is the width coordinate of the square grid unit, y j is the height coordinate in the square grid unit.
[0040] On the other hand, a slag melting performance evaluation system is provided, which includes: a memory, a processor, and a computer program stored in the memory, characterized in that the processor executes the computer program to implement any of the above-mentioned methods.
[0041] The beneficial effects of the above technical solution of the present invention are as follows:
[0042] The method provided by an embodiment of the present invention comprises: acquiring an image of the slag at an initial temperature; binarizing the image at the initial temperature to obtain the initial area of the slag at the initial temperature; acquiring an image at any time during the slag heating and melting process; binarizing the image at any time during the slag heating and melting process to obtain the real-time area of the slag during the heating and melting process; obtaining an area change rate based on the real-time area and the initial area; and evaluating the slag melting performance based on the area change rate. The embodiment of the present invention continuously captures images of the slag during the heating and melting process, and uses the change in the entire area of the slag instead of the change in height to evaluate the slag melting performance. This allows for a comprehensive evaluation of the slag melting process, thereby improving the accuracy of the slag melting performance evaluation. BRIEF DESCRIPTION OF THE DRAWINGS
[0043] Figure 1 A schematic flow chart of a slag melting performance evaluation method provided in an embodiment of the present invention;
[0044] Figure 2 Schematic diagram of the slag heating and melting process: (a) - original image of the slag at room temperature; (b) - image at 75% of the original height; (c) - image at 50% of the original height; (d) - image at 25% of the original height;
[0045] Figure 3 Screenshots of images taken during the slag heating and melting process, (a) - original image; (b) - screenshot at high temperature;
[0046] Figure 4The area changes with temperature during the slag melting process. The inset shows a local enlargement of the 1240-1285℃ range.
[0047] Figure 5 The area changes with temperature during the slag melting process. The inset shows a local enlargement of the 1240-1290℃ range.
[0048] Figure 6 This is a schematic diagram of slag image binarization;
[0049] Figure 7 Grid division for the initial image;
[0050] Figure 8 Grid division of the image at any time. DETAILED DESCRIPTION
[0051] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.
[0052] In view of the shortcomings of the current method of evaluating the melting performance of slag by height and the oversimplification of the method, the present invention continuously captures images of the slag during the heating and melting process, and uses the change in the entire area of the slag instead of the change in height to evaluate the melting performance of the slag.
[0053] See Figure 1 The embodiment of the present invention provides a method for evaluating slag melting performance, the method comprising:
[0054] S101, obtaining an image at the initial temperature of the slag.
[0055] S102 , performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature.
[0056] S103: Acquire images at any time during the slag heating and melting process.
[0057] S104 , performing binarization processing on the image at any time during the slag heating and melting process to obtain the real-time area of the slag during the melting process.
[0058] S105: Obtain an area change rate according to the real-time area and the initial area.
[0059] S106. Evaluate the slag melting performance based on the area change rate.
[0060] The method provided by the embodiment of the present invention has at least the following beneficial effects:
[0061] The method provided by an embodiment of the present invention comprises: acquiring an image of the slag at an initial temperature; binarizing the image at the initial temperature to obtain the initial area of the slag at the initial temperature; acquiring an image at any time during the slag heating and melting process; binarizing the image at any time during the slag heating and melting process to obtain the real-time area of the slag during the heating and melting process; obtaining an area change rate based on the real-time area and the initial area; and evaluating the slag melting performance based on the area change rate. The embodiment of the present invention continuously captures images of the slag during the heating and melting process, and uses the change in the entire area of the slag instead of the change in height to evaluate the slag melting performance. This allows for a comprehensive evaluation of the slag melting process, thereby improving the accuracy of the slag melting performance evaluation.
[0062] The method provided by the embodiment of the present invention will be further explained and described below through optional embodiments.
[0063] In an optional embodiment, performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature includes:
[0064] The binarized initial temperature image is divided into a plurality of square grid units, and the sum of the image areas of the initial temperature in all square grid units is taken as the initial area.
[0065] S101, obtaining an image at the initial temperature of the slag.
[0066] Furthermore, the embodiment of the present invention uses a CCD high-speed camera to capture a side image of the slag at the initial temperature and records the temperature corresponding to the image.
[0067] S102 , performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature.
[0068] It should be noted that image binarization is the process of setting the grayscale value of the pixels on the image to 0 or 255, that is, the entire image appears to be black and white. Image binarization greatly reduces the amount of data in the image, thereby highlighting the outline of the target.
[0069] The image at the initial temperature is binarized to obtain a black and white image, and the black area in the black and white image is calculated, which is the initial area of the slag at the initial temperature.
[0070] In an optional embodiment, performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature includes:
[0071] The binarized initial temperature image is divided into a plurality of square grid units, and the sum of the image areas of the initial temperature in all square grid units is taken as the initial area.
[0072] In an optional embodiment, the area where the area of the square grid unit tends to be infinitely small is used as a pixel point, and the number of pixel points in the initial temperature image is counted as the initial area.
[0073] As an example, the original image collected in the experiment is as follows Figure 3 As shown. Figure 3 The graphic boundary of the slag in the furnace is irregular and cannot be described by a specific mathematical function relationship. The calculation of its area is difficult. Therefore, the embodiment of the present invention uses the integration method to calculate the approximate value of the area. Figure 3 It is divided into countless square grids. When the area of the grid approaches infinitesimal, the number of white grids in the statistical image is the area of the slag.
[0074] In an optional embodiment, counting the number of pixels in the image of the initial temperature as the initial area includes:
[0075] Obtain the pixel value of the image pixel point of the initial temperature in the square grid unit, when the pixel value is less than the first threshold, set the pixel value to 0, when the pixel value is greater than or equal to the first threshold, set the pixel value to 255;
[0076] Get the number of pixels with a pixel value equal to 255, and use the number of image pixels with an initial temperature equal to 255 as the initial area.
[0077] Furthermore, for an image, the smallest unit cell is a pixel. Therefore, as long as the pixel points of the slag in the image can be counted, the area of the slag can be obtained. However, since the original image is a grayscale image, each pixel point is represented by a number between 0 and 255. The embodiment of the present invention obtains the pixel values of the image pixels at the initial temperature in the square grid unit, and defines that when the pixel value is less than a first threshold, the pixel value is set to 0, and when the pixel value is greater than or equal to the first threshold, the pixel value is set to 255; the number of pixel points with a pixel value equal to 255 is counted, and the number of image pixels with an initial temperature equal to 255 is used as the initial area, thereby distinguishing the slag pattern from the environment.
[0078] In an optional embodiment, the initial area is obtained according to the following formula:
[0079] S0=ΣF0(x i ,y j ), i = 0 ~ W + 1; j = 0 ~ H + 1
[0080] Where:
[0081] S0 is the initial area;
[0082] W is the number of pixels in the width direction of the square grid unit;
[0083] H is the number of pixels in the height direction of the square grid unit;
[0084] F0(x i ,y j ) is the pixel point with a pixel value of 255 in the image of the initial temperature, x i is the width coordinate of the square grid unit, y j is the height coordinate in the square grid unit.
[0085] For the division of square grid units, please refer to Figure 6 .
[0086] S103: Acquire images at any time during the slag heating and melting process.
[0087] It can be understood that the embodiment of the present invention obtains images of the slag at the initial temperature and the images during the heating and melting process by continuously capturing side images of the slag during the heating and melting process using a CCD high-speed camera and recording the temperature corresponding to the image.
[0088] S104 , performing binarization processing on the image at any time during the slag heating and melting process to obtain the real-time area during the slag heating and melting process.
[0089] In an optional embodiment, binarization processing is performed on an image at any time during the slag heating and melting process to obtain a real-time area during the slag heating and melting process, including:
[0090] The image at any moment after binarization is divided into multiple square grid units, and the sum of the image areas at any moment in all square grid units is taken as the real-time area. Figure 6 shown.
[0091] In an optional embodiment, when the image area at any moment in the square grid unit tends to be infinitely small, that is, the number of pixels in the image at any moment is counted as the real-time area.
[0092] In an optional embodiment, counting the number of pixels in an image at any time as the real-time area includes:
[0093] Obtain the pixel value of a pixel point in the image at any time in the square grid unit. When the pixel value is less than a second threshold, the pixel value is set to 0; when the pixel value is greater than or equal to the second threshold, the pixel value is set to 255.
[0094] Get the number of pixels with a pixel value equal to 255, and take the number of image pixels equal to 255 at any time as the real-time area.
[0095] In an optional embodiment, the real-time area is obtained according to the following formula:
[0096] S1=ΣF1(x i ,y j ), i = 0 ~ W + 1; j = 0 ~ H + 1
[0097] Where:
[0098] S1 is the real-time area;
[0099] W is the number of pixels in the width direction of the square grid unit;
[0100] H is the number of pixels in the height direction of the square grid unit;
[0101] F1(x i ,y j ) is the pixel point with a pixel value equal to 255 in the square grid unit at any time, x i is the width coordinate of the square grid unit, y j is the height coordinate in the square grid unit.
[0102] For the division of square grid units, please refer to Figure 7 .
[0103] Furthermore, a counting method may be used to calculate the area of the slag, that is, to count the number of slag points in the image after binarization processing.
[0104] S105: Obtain an area change rate according to the real-time area and the initial area.
[0105] In an optional embodiment, the rate of change of the real-time area to the initial area is calculated according to the following formula:
[0106] K = A / A0, where K is the image area change rate; A is the real-time area of the slag at any moment;
[0107] A0 is the initial area of the slag at the initial temperature.
[0108] S106. Evaluate the slag melting performance based on the area change rate.
[0109] See Figure 4 In this embodiment of the present invention, a curve is plotted using the area change rate (K) as the ordinate and the temperature (T) as the abscissa. In the KT curve, the following definitions are defined: K = 0.75 corresponds to the slag melting temperature; K = 0.50 corresponds to the slag melting temperature; K = 0.25 corresponds to the slag fluidity temperature; and K > 1 indicates expansive slag. This allows the slag's melting properties to be evaluated.
[0110] In an optional embodiment, the first threshold value is equal to the second threshold value. As an example, the first threshold value and the second threshold value may be 211.
[0111] The method provided by the embodiment of the present invention has important application value in comprehensively evaluating the melting performance of slag in ironmaking, molten iron pretreatment, steelmaking and continuous casting processes.
[0112] The method provided by the embodiments of the present invention is further described below through specific examples.
[0113] Example 1: Slag melting performance evaluation method process is as follows:
[0114] (1) The slag was pressed into a cylindrical sample with a diameter of 3 mm and a height of 3 mm, and then placed in an electric furnace.
[0115] (2) The electric furnace is heated according to the set program, and the CCD high-speed camera is turned on to capture the image of the slag sample and record the corresponding temperature.
[0116] (3) The captured slag sample image is binarized, as shown in the following example: Figure 6 shown.
[0117] (4) Calculate the area of the slag sample using the counting method.
[0118] (5) Draw the KT curve, such as Figure 4 shown.
[0119] (6) Result analysis: The slag starts to melt at 1260.0℃, the melting temperature is 1265.0℃, and the fluidity temperature is 1280.0℃. Figure 4 It can be seen that the slag expands by 20.0% during the process from solid powder at room temperature to complete melting at high temperature.
[0120] Example 2: Slag melting performance evaluation method process is as follows:
[0121] (1) The slag was pressed into a cylindrical sample with a diameter of 3 mm and a height of 3 mm, and then placed in an electric furnace.
[0122] (2) The electric furnace is heated according to the set program, and the CCD high-speed camera is turned on to capture the image of the slag sample and record the corresponding temperature.
[0123] (3) The captured slag sample image is binarized, as shown in the following example: Figure 6 shown.
[0124] (4) Calculate the area of the slag sample using the counting method.
[0125] (5) Draw the KT curve, such as Figure 5 shown.
[0126] (6) Result analysis. The slag starts to melt at 1259.0℃, the melting temperature is 1264.0℃, and the fluidity temperature is 1272.0℃. Figure 5 It can be seen that the slag expands less, only 5.0%, during the process from solid powder at room temperature to complete melting at high temperature.
[0127] On the other hand, an embodiment of the present invention provides a slag melting performance evaluation system, which includes: a memory, a processor, and a computer program stored in the memory, characterized in that the processor executes the computer program to implement any of the above methods.
[0128] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.
Claims
1. A method for evaluating slag melting performance, characterized in that: The method evaluates the slag melting process; comprising: Continuously capturing images of the slag during the heating and melting process; acquiring images of the slag at the initial temperature; Performing binarization processing on the image at the initial temperature to obtain the initial area of the slag at the initial temperature; Acquire images at any time during the slag heating and melting process; Binarizing the image at any time during the slag heating and melting process to obtain the real-time area of the slag during the heating and melting process; Obtaining an area change rate according to the real-time area and the initial area; The slag melting performance is evaluated based on the area change rate.
2. The slag melting performance evaluation method according to claim 1, characterized in that: The image at the initial temperature is binarized to obtain the initial area of the slag at the initial temperature, including: The binarized image of the initial temperature is divided into a plurality of square grid units, and the sum of the image areas of the initial temperature in all the square grid units is taken as the initial area.
3. The slag melting performance evaluation method according to claim 2, characterized in that: The area when the area of the square grid unit tends to be infinitely small is taken as a pixel point, and the number of pixel points in the image of the initial temperature is counted as the initial area.
4. The slag melting performance evaluation method according to claim 3, characterized in that: Counting the number of pixels in the image of the initial temperature as the initial area includes: Obtaining a pixel value of an image pixel point of the initial temperature in the square grid unit, and setting the pixel value to 0 when the pixel value is less than a first threshold value, and setting the pixel value to 255 when the pixel value is greater than or equal to the first threshold value; The number of pixel points whose pixel value is equal to 255 is obtained, and the number of image pixel points whose initial temperature is equal to 255 is used as the initial area.
5. The slag melting performance evaluation method according to claim 4, characterized in that: The initial area is obtained according to the following formula: S0=ΣF0(x i ,y j ),i=0~W+1;j=0~H+1 Where: S0 is the initial area; W is the number of pixels in the width direction of the square grid unit; H is the number of pixels in the height direction of the square grid unit; F0(xi,yj) is the pixel point with a pixel value equal to 255 in the initial temperature image, xi is the width direction coordinate in the square grid unit, and yj is the height direction coordinate in the square grid unit.
6. The slag melting performance evaluation method according to claim 1, characterized in that: Binarization is performed on the image at any time during the slag heating and melting process to obtain the real-time area during the slag heating and melting process, including: The binarized image at any time is divided into a plurality of square grid units, and the sum of the image areas at any time in all the square grid units is used as the real-time area.
7. The slag melting performance evaluation method according to claim 6, characterized in that: When the area of the square grid unit tends to be infinitely small, the number of pixel points in the image at any time is counted as the real-time area.
8. The slag melting performance evaluation method according to claim 7, characterized in that: Counting the number of pixels in the image at any time as the real-time area includes: Obtaining a pixel value of a pixel point in the image at any moment in the square grid unit, and setting the pixel value to 0 when the pixel value is less than a second threshold value, and setting the pixel value to 255 when the pixel value is greater than or equal to the second threshold value; The number of pixel points whose pixel value is equal to 255 is obtained, and the number of image pixel points equal to 255 at any moment is used as the real-time area.
9. The slag melting performance evaluation method according to claim 8, characterized in that: The real-time area is obtained according to the following formula: S1=ΣF1(x i ,y j ),i=0~W+1;j=0~H+1 Where: S1 is the real-time area; W is the number of pixels in the width direction of the square grid unit; H is the number of pixels in the height direction of the square grid unit; F1(x i ,y j ) is a pixel point with a pixel value equal to 255 in the square grid unit at any time.
10. A slag melting performance evaluation system, characterized in that: The system comprises: a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the method according to any one of claims 1 to 9.