Method for estimating slopping amount, system for estimating slopping amount, and refining method

Abstract

This method estimates the amount of slopping from the refining vessel at a lower cost compared to using a weighing scale, and with higher accuracy than methods that determine the amount of slopping from the radiant energy of slopping. [Solution] The method for estimating the amount of slopping involves photographing the slopping flow flowing out of the refining vessel, determining the width of the slopping flow from the photographed image, using the sum of the obtained widths as the slopping index, and estimating the amount of slopping by multiplying the slopping index by a proportionality constant.

Description

Technical Field

[0001] The present disclosure relates to a method for estimating the amount of slopping, an estimation system for the amount of slopping, and a refining method.

Background Art

[0002] The converter refining process is an important process for reducing impurities such as silicon, phosphorus, and carbon in hot metal discharged from a blast furnace. In particular, phosphorus segregates at grain boundaries, significantly affecting the crack sensitivity of steel, and is known to significantly degrade the mechanical properties of steel, such as reducing low-temperature toughness and generating abnormal structures in the central segregation part during continuous casting. Therefore, it is required to stably reduce the phosphorus concentration in steel as much as possible. Some of these impurities are removed by oxidation into slag whose basicity is adjusted by adding quicklime or the like by blowing high-pressure oxygen gas onto the hot metal. At this time, optimizing the input amount of auxiliary materials and the oxygen supply amount by grasping the amount of slag in the converter is important for reducing the slag discharge amount and auxiliary material cost, as well as reducing operation variations. However, the inside of the converter is a high-temperature and dusty environment, and it is not easy to sense the amount of slag in the furnace. Furthermore, the slag in the furnace foams due to CO gas generated by the refining reaction, increasing its volume. Such a phenomenon is called slag forming, and slag forming varies depending on the operating conditions of the input auxiliary materials and oxygen supply. When slag forming is intense, a phenomenon called slopping may occur, where slag overflows from the furnace mouth. Slopping may require cleaning under the furnace, leading to a decrease in productivity. In addition, the change in the amount of slag in the furnace causes disturbances to the optimization of the input amount of auxiliary materials and the oxygen supply amount in the subsequent refining process. This disturbance leads to variations in the steelmaking components, and an operation of overfeeding auxiliary materials is carried out considering such variations. As methods for estimating the amount of slopping in various refining vessels, the following Patent Documents 1 and 2 are known.

[0003] Patent Document 1 discloses a method in which all of the slopping falling from the converter is within the detection field, slopping is detected by a radiant energy detector installed on the underside of the converter, and the amount of slopping is estimated from the integrated value of that energy.

[0004] Patent Document 2 discloses a method for estimating the amount of slag remaining in a converter by directly weighing the amount of slag flowing out of the converter using a weighing machine installed in the slag pan, and estimating the amount of slag generated by the refining reaction and the amount of slopping directly weighed. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Utility Model Publication No. 57-39950 [Patent Document 2] Japanese Patent Application Publication No. 7-041813 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, in Patent Document 1, the amount of slopping is determined from the radiant energy of the slopping material falling from the converter, and is therefore strongly affected by the temperature of the overflowing slag. As a result, there is a problem in that the accuracy of estimating the amount of slopping is low due to the variation in the temperature of the overflowing slag.

[0007] Patent Document 2 states that when using a weighing machine attached to a slag receiving cart or the like, there are challenges in the installation and maintenance of the weighing machine.

[0008] Therefore, this disclosure aims to estimate the amount of slopping from a refining vessel at a lower cost than using a weighing scale, and with higher accuracy than determining the amount of slopping from the radiant energy of slopping. [Means for solving the problem]

[0009] A method for estimating the amount of slopping according to a first aspect of this disclosure involves photographing the slopping flow flowing out of a refining vessel, determining the width of the slopping flow from the photographed image, using the sum of the obtained widths as the slopping index, and estimating the amount of slopping by multiplying the slopping index by a proportionality constant.

[0010] A second aspect of the present disclosure is a method for estimating the amount of slopping, in which, in the method for estimating the amount of slopping according to the first aspect, the proportionality constant is set based on the measured amount of slopping.

[0011] A third aspect of the present disclosure is a method for estimating the amount of slopping, which involves photographing the slopping flow flowing out of a refining vessel, determining the width and flow velocity of the slopping flow from the photographed image, and estimating the amount of slopping using the following equation (1).

number

[0012] A fourth aspect of the present disclosure is a method for estimating the amount of slopping, in which, in any one of the first to third aspects of the method for estimating the amount of slopping, the image is taken so as to include both sides of the refining vessel.

[0013] A fifth aspect of the present disclosure is a method for estimating the amount of slopping, in which the slopping amount is estimated in any one of the first to third aspects, and the smelting vessel is viewed from above and photographed from different directions.

[0014] The method for estimating the amount of slopping according to the sixth aspect of the present disclosure is the method for estimating the amount of slopping according to any one of the first to fourth aspects, wherein a photographing device is used to monitor the occurrence of a slopping flow in the refining vessel, and a control device for acquiring monitoring information from the photographing device is used to detect the occurrence of the slopping flow in the refining vessel. When the occurrence of the slopping flow is detected, the photographing of the slopping flow by the photographing device is started.

[0015] The method for estimating the amount of slopping according to the seventh aspect of the present disclosure is the method for estimating the amount of slopping according to the sixth aspect, wherein when a substance having a luminance value higher than a predetermined value than the background is recognized within the monitoring area of the photographing device, the substance is detected as the slopping flow.

[0016] The method for estimating the amount of slopping according to the eighth aspect of the present disclosure is the method for estimating the amount of slopping according to the sixth aspect, wherein when a substance having a luminance value higher than a predetermined value than the background is recognized within the monitoring area of the photographing device and the number of recognized pixels is equal to or more than a predetermined number of pixels in the monitoring area, the substance is detected as the slopping flow.

[0017] The slopping amount estimation system according to the ninth aspect of the present disclosure includes a photographing device for photographing a slopping flow flowing out of a refining vessel, and a control device that obtains the width of the slopping flow from the photographed image, uses the total value of the obtained widths as a slopping index, and executes a process of estimating the slopping amount by multiplying the slopping index by a proportionality constant.

[0018] The refining method according to the tenth aspect of the present disclosure determines the amount and composition of slag in the refining vessel based on the estimated slopping amount estimated using the method for estimating the slopping amount according to any one of the first to third aspects, and adjusts at least one of the input amount of the auxiliary raw material and the acid feeding amount.

Advantages of the Invention

[0019] According to the present disclosure, it is possible to estimate the amount of slopping from the refining vessel at a lower cost compared to using a weighing device, and with higher accuracy compared to obtaining the amount of slopping from the radiated energy of slopping.

Brief Description of the Drawings

[0020] [Figure 1] It is a longitudinal sectional view of a refining vessel used in an estimation system for the amount of slopping according to an embodiment of the present disclosure. [Figure 2] It is a top view of the refining vessel shown in FIG. 1 as viewed from above. [Figure 3] It is a diagram showing the configuration of a control device. [Figure 4] It is a view of the upright refining vessel as viewed from the side, showing a state where slopping is occurring. [Figure 5] It is a graph showing the estimated slopping amounts of Examples 1 to 5 to which the method for estimating the amount of slopping according to the present disclosure is applied. [Figure 6] It is a graph showing the relationship between the estimated slopping amount and the basicity (-) of the slag after treatment. [Figure 7] It is a graph showing the relationship between the examples considering slopping and the comparative examples not considering slopping, and the basicity (-) of the slag after treatment. [Figure 8] It is a top view of a refining vessel used in an estimation system for the amount of slopping according to other embodiments as viewed from above.

Modes for Carrying Out the Invention

[0021] Hereinafter, embodiments for carrying out the technology of this disclosure will be described with reference to the drawings. Components indicated by the same reference numerals in each drawing are the same or similar components. In the embodiments described below, descriptions and reference numerals that are repeated may be omitted. Furthermore, the drawings used in the following description are all schematic, and the dimensional relationships and ratios of each element shown in the drawings do not necessarily correspond to reality. Also, the dimensional relationships and ratios of each element do not necessarily correspond between multiple drawings.

[0022] First, the converter 20 used in the method for estimating the slopping amount of this embodiment will be described. Note that the converter 20 is an example of a refining vessel in this disclosure.

[0023] As shown in Figure 1, the converter 20 comprises a bottom 20A, a furnace wall 20B, a furnace opening 20C, and a tapping hole 20D provided in the furnace wall 20B. The converter 20 is also configured to tilt by a tilting mechanism 24 (see Figure 3). During or after smelting, when the converter 20 is upright, slopping may occur in which slag overflows (flows out) from the furnace opening 20C. The flow of slag that flows out from the furnace opening 20C due to this slopping will be referred to as the slopping flow below. The slopping flow that flows out of the upright converter 20 usually falls directly down into the furnace.

[0024] Next, the slopping amount estimation system using the converter 20 of this embodiment (hereinafter referred to as the "estimation system" as appropriate) will be described. The estimation system of this embodiment is a system that estimates the slopping amount using image analysis. Specifically, it is a system that estimates the slopping amount (slopping mass) by determining the width of the slopping flow PF from an image of the slopping flow PF when slopping occurs. This estimation system comprises an imaging device 40 and a computer 42 as an example of an estimation device.

[0025] The imaging device 40 is a device that has the function of imaging the slopping flow PF flowing out of the converter 20. Specifically, as shown in Figure 1, the imaging device 40 is positioned to the side of the converter 20 and images the slopping flow PF that overflows from the furnace opening 20C of the converter 20 and flows downward when slopping occurs. Note that the arrow UP in Figure 1 points upward. Also, the arrow SD in Figure 1 points in the imaging direction of the imaging device 40.

[0026] The imaging device 40 photographs an area where the slopping flow can be observed flowing out and falling from the furnace opening 20C of the converter 20 when it is not tilted, i.e., in an upright state. Specifically, as shown in Figure 2, the imaging device 40 takes images that include both sides of the converter 20. That is, the position and focus of the imaging device 40 are set so that both sides of the converter 20 are within the imaging area of ​​the imaging device 40. In this embodiment, one imaging device 40 is positioned to the side of the converter 20 and is configured to photograph both sides of the converter 20 within its imaging area. However, this disclosure is not limited to this configuration, and the imaging device 40 may be positioned in front of or behind the converter 20.

[0027] For example, a CCD camera or a CMOS camera may be used as the imaging device 40.

[0028] The imaging device 40 is connected to the computer 42 by wire or wireless connection. Image information captured by the imaging device 40 is transmitted to the computer 42. The image information transmitted from the imaging device 40 may be still image information captured at predetermined time intervals (for example, every second) or video image information.

[0029] The imaging device 40 may also be equipped with a limiting filter (for example, a neutral density filter) or a bandpass filter to limit the amount of incident light so that the brightness of the slopping flow PF, which is a high-luminance substance, does not saturate in the captured image.

[0030] Computer 42 is a device that has the function of estimating the amount of slopping based on the image captured by the imaging device 40. Specifically, Computer 42 obtains the width L of the slopping flow PF from the image captured by the imaging device 40, uses the sum of the obtained widths L as the slopping index, and performs a process to estimate the amount of slopping by multiplying the slopping index by a coefficient X, which is a proportionality constant.

[0031] The computer 42 determines that slopping has occurred when high-luminance material is captured while the converter 20 is not tilted (i.e., in an upright state), and executes a process to estimate the amount of slopping. Specifically, the computer 42 determines that slopping has occurred when, while the converter 20 is not tilted, high-luminance material (also called a high-luminance subject) with a luminance difference of 30 or more compared to the background of the captured image is observed in 0.05% or more of the total number of pixels in the captured image. For example, if a luminance value expressed in 256 gradations (0 to 255) is used as the luminance value, high-luminance material with a luminance value of 30 or more and 255 or less may be detected as slopping flow. Here, the background refers to the part of the captured image other than the high-luminance material, for example, the part with a luminance value of 0 or more and 29 or less. Note that the luminance difference between the background and the high-luminance material, and the proportion of the total number of pixels in the captured image that the high-luminance material occupies, will vary depending on the shooting environment and shooting conditions, so it is advisable to set the conditions appropriately so that slopping flow can be detected.

[0032] Furthermore, the imaging device 40 constantly monitors the imaging area when in operation, and when a high-luminance substance is detected in this imaging area, it may record the contents of the imaging area as an image, i.e., start imaging. Recognition of the high-luminance substance in this imaging area may be performed by the computer 42 or by the image processing unit mounted on the imaging device 40, but in this embodiment, as an example, the computer 42 is used to recognize the high-luminance substance. When the computer 42 is used to recognize the high-luminance substance, the imaging function of the imaging device 40 is controlled by the computer 42.

[0033] As shown in Figure 3, the computer 42 receives sequential image information of the slopping flow PF captured by the camera 40. The computer 42 analyzes the received image information to determine the width L of the slopping flow PF. Here, if the image information transmitted from the camera 40 is still image information, the computer 42 analyzes each still image. On the other hand, if the image information transmitted from the camera 40 is video image information, the computer 42 extracts still images from the video at predetermined time intervals (for example, every second) and analyzes each extracted still image. From the viewpoint of improving the estimation accuracy of the slopping flow PF, the computer 42 may, for example, have the camera 40 capture 10 or more still images per second and analyze each captured still image, or it may extract 10 or more still images per second from the video captured by the camera 40 and analyze each extracted still image.

[0034] The position from which the width L of the slopping flow PF is determined from the captured image is a predetermined distance H downward from the furnace opening 20C of the upright converter 20 (see Figure 4).

[0035] In the image analysis of still images by the computer 42, the still image is first binarized. Specifically, since the slopping flow PF has a higher brightness value than the background, a threshold value is set, for example, that is 30 or more higher in brightness than the background, and the still image is binarized based on this threshold. Then, the length (horizontal length) of the high-brightness portion of the slopping flow PF within the pre-set analysis area is measured as the apparent length. Specifically, this is measured from the number of pixels in the horizontal direction of the slopping flow at an arbitrary position, based on the distance per pixel of the still image, which is geometrically calculated from the magnification of the imaging device 40 and the distance between the imaging device 40 and the slopping flow. At this time, if the slopping flow is divided horizontally, the sum of the widths of each slopping flow is taken as the width L of the still image. Then, the slopping index is obtained by summing all the width values ​​obtained from the analysis of the images in which the slopping was captured. The slopping index semi-quantitatively represents the amount of slopping. By multiplying this slopping index by a coefficient X, which is a proportionality constant, the actual amount of slopping (measured amount of slopping) and the slopping index will match. Here, the coefficient X should be set based on the measured amount of slopping. For example, the actual amount of slopping may be determined by directly weighing the slopping using a load cell or the like, or it may be calculated from the mass balance in the converter 20. The coefficient X may also be determined from the regression equation obtained by regression between the slopping index and the actual amount of slopping.

[0036] As shown in Figure 3, the computer 42 includes a CPU (Central Processing Unit) 43, a main memory 44 that provides temporary storage, an auxiliary storage device 45 that provides non-volatile storage, and an input / output interface (I / F) 46. The CPU 43, main memory 44, auxiliary storage device 45, and I / F 46 are connected to each other via a bus 47.

[0037] The auxiliary storage device 45 can be implemented using a Hard Disk Drive (HDD), Solid State Drive (SSD), flash memory, etc. The auxiliary storage device 45 stores an estimation program 48 that causes the computer 42 to function as a device for estimating the amount of slopping in the converter 20. The CPU 43 reads the estimation program 48 from the auxiliary storage device 45, loads it into the main memory 44, and sequentially executes the processes described in the estimation program 48, thereby enabling the computer 42 to function as a device for estimating the amount of slopping in the converter 20.

[0038] The input / output interface 46 is connected to the imaging device 40. This configuration allows image information captured by the imaging device 40 to be stored in the auxiliary storage device 45 via the input / output interface 46 and simultaneously analyzed by the CPU 43.

[0039] Next, a method for estimating the amount of slopping using the converter 20 of this embodiment will be described. The method for estimating the amount of slopping in this embodiment is a method that estimates the amount of slopping using image analysis. Specifically, it is a method of estimating the amount of slopping (slopping mass) by determining the width of the slopping flow PF from an image of the slopping flow PF when slopping occurs. More specifically, it is a method of estimating the amount of slopping by photographing the slopping flow PF flowing out of the converter 20, determining the width L of the slopping flow PF from the photographed image, using the sum of the obtained widths L as the slopping index, and multiplying the slopping index by a coefficient X, which is a proportionality constant.

[0040] First, the imaging device 40 constantly monitors the imaging area. When a high-luminance substance is detected in the imaging area, it records the conditions within the imaging area as an image, i.e., it starts imaging. If it is determined that slopping is occurring by analyzing the captured image, the width L of the slopping flow PF is determined from the captured image. Specifically, the image of the slopping flow PF is analyzed by the computer 42 to determine the width L of the slopping flow PF.

[0041] Then, the sum of the calculated widths L is used as the slopping index, and the amount of slopping is estimated by multiplying the slopping index by a coefficient X, which is a proportionality constant.

[0042] Based on the estimated amount of slopping described above, the amount and composition of slag in the converter 20 are recalculated, and the amount of auxiliary materials added and the amount of acid supplied are adjusted. Specifically, the ratio of CaO concentration to SiO2 concentration (hereinafter referred to as basicity) of the slag that flows out of the converter 20 due to slopping may be about the same as the basicity of the slag charged into the furnace, or it may be about 0.1 to 0.5 less. This is because, at the stage when slopping occurs, the slag of auxiliary materials such as quicklime that have been added has not yet been slagtled, and the basicity of the slag that flows out due to slopping may be smaller than the charged basicity (the theoretical basicity value calculated from the amount of molten iron components and added auxiliary materials).

[0043] The amount of slag in the converter 20 can be estimated by subtracting the estimated slopping amount from the amount of SiO2, P2O5, etc., produced by the refining reaction of the charged molten iron and the amount of auxiliary materials added. Furthermore, regarding the slag composition in the furnace, for example, the basicity of the slag remaining in the furnace can be estimated from the estimated slopping amount and the basicity of the slag that flows out of the furnace due to the slopping.

[0044] Next, the effects and advantages of this embodiment will be described. The disclosers hypothesized that by analyzing images of slopping, they could determine the width L of the slopping flow and then estimate the amount of slopping. Furthermore, they believed that estimating the amount of slopping non-contact through image analysis would reduce the impact of high-temperature environments compared to direct weighing, thus solving maintenance and cost issues. They also considered that the difficulty in estimating the amount of slopping stemmed from the fact that the slopping flow occurs around the entire circumference of the furnace. Specifically, even if only a portion of the furnace is photographed, it is impossible to analyze the slopping flow occurring in other areas. While installing multiple imaging devices would allow for imaging the entire furnace circumference, this presents challenges such as equipment failure due to the scattering of high-temperature materials and maintenance issues. Therefore, the disclosers considered using at least one imaging device to photograph a portion of the converter 20 and estimating the total amount of slopping from the analysis of the resulting slopping flow images. In other words, they assumed that the slopping flow occurred uniformly around the entire circumference of the converter 20, and detected the slopping flow and estimated its amount by photographing a portion of the converter 20. As a result, they were able to accurately estimate the amount of slopping. In other words, in the slopping amount estimation method and estimation system of this embodiment, the slopping flow PF flowing out of the converter 20 is photographed, the width L of the slopping flow PF is determined from the photographed image, the sum of the obtained widths L is used as the slopping index, and the slopping amount is estimated by multiplying the slopping index by a coefficient X which is a proportionality constant, thereby enabling the estimation of the slopping amount with high accuracy.

[0045] Furthermore, in this embodiment, since the coefficient X is set based on the measured slopping amount, it becomes possible to estimate the slopping amount with higher accuracy compared to, for example, a configuration that sets it based on a theoretical value.

[0046] (Other embodiments) In the embodiment described above, the width L of the slopping flow PF is determined from the captured image, the sum of the obtained widths L is used as the slopping index, and the amount of slopping is estimated by multiplying the slopping index by a coefficient X which is a proportionality constant. However, this disclosure is not limited to this configuration. For example, the width and falling velocity of the slopping flow may be determined from the captured image, and the amount of slopping may be estimated using the following equation (1). Specifically, the computer 42 determines the width L of the slopping flow PF, and then determines the flow velocity V (m / s) from the captured image. The flow velocity V (m / s) is calculated by assuming that the flow velocity V (m / s) of the slopping flow PF at the measurement position of width L (a position at a predetermined distance H from the furnace opening 20C shown by the dashed line in Figure 4) is the free fall of the slopping flow PF (2gH). 0.5 Alternatively, the distance traveled by the slopping flow PF may be determined by pattern matching from at least two images, and then divided by the difference (s) in the timestamps (times) between the images used to determine the distance traveled. If we assume that the flow velocity V (m / s) is the free fall of the slopping flow PF, the computer 42 will use image analysis from the captured still images to determine the distance H (m) from the measurement position with width L to the point where the slopping flow PF begins to flow out of the furnace opening 20C.

[0047] Then, computer 42 calculates the slopping amount M using the following equation (2).

[0048]

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[0049] The bulk density ρ of the slag may be determined from the amount of slag present in the furnace and the geometric shape of the furnace. The correction parameter α may be set to match the actual amount of slopping.

[0050] Using equation (1) above produces the same effects as using the coefficient X mentioned earlier.

[0051] In the embodiment described above, a single imaging device 40 is used to photograph the side of the converter 20, but the disclosure is not limited to this configuration. For example, as shown in Figure 8, multiple imaging devices 40 may be used to photograph areas of the converter 20 that cannot be photographed by a single imaging device 40. In the example shown in Figure 8, the converter 20 is photographed by two imaging devices 40 from opposite directions.

[0052] In the embodiments described above, the converter 20 is an example of a refining vessel, but the disclosure is not limited to this configuration. The refining vessel may be, for example, an electric furnace, a molten steel ladle, or a torpedo car.

[0053] (Example test) Next, we examined the effects that can be obtained by the technology disclosed herein. Table 1 shows the conditions for Test Examples 1-5 conducted under MURC operation. In Examples 1-5 and the Comparative Example, the slopping process in the converter was captured using a single camera at a rate of 30 still images per second. The images were taken of the side of the converter, which is the area from which slag can flow out of the slag discharge port of the converter, which serves as the refining vessel. This makes it possible to capture the slopping flow when slopping occurs.

[0054] [Table 1]

[0055] In Examples 1-5, a bandpass filter that transmits only wavelengths of 690±10nm was installed on the camera for imaging. The sum of the widths of the slopping flow obtained from the analysis of the captured images was used as the slopping index, and the amount of slopping was estimated using a pre-determined coefficient X (=0.0001). The unit of the width value was mm.

[0056] Figure 5 shows the results for Examples 1 to 5. From Figure 1, it can be seen that in the examples of this test, the slopping amount was measured to be approximately 0.1t to 3t.

[0057] Figure 6 shows the relationship between the estimated slopping amount and the analytical value of the basicity of the slag after MURC treatment in the example. From Figure 6, it can be seen that the greater the slopping amount, the greater the basicity of the slag after MURC treatment tends to be. Since the basicity released due to slopping is smaller than the input basicity of Blow 1, in charges where a lot of slopping occurs, slag with high basicity is carried over to Blow 2. Therefore, if the target basicity of Blow 2 is constant, the actual basicity of Blow 2 in charges where a lot of slopping occurs will be relatively high. This is consistent with the results shown in Figure 6, and therefore it is considered that the estimation of the slopping amount in this disclosure was done accurately.

[0058] Figure 7 shows the relationship between the analytical value of the basicity of slag after MURC treatment, the estimated basicity of slag after MURC treatment considering slopping, and the estimated basicity of slag after MURC treatment without considering slopping. The estimated basicity of slag after MURC treatment considering slopping is the basicity estimated by mass balance calculation using the amount of slopping estimated in the example and the amount of waste estimated using the same method as PCT / JP2023 / 028351. The basicity of slag discharged due to slopping was assumed to be 1.0. The estimated basicity of slag after MURC treatment without considering slopping is the basicity estimated by mass balance calculation using only the amount of waste estimated using the same method as PCT / JP2023 / 028351, without using the amount of slopping estimated in the example. From Figure 7, it can be seen that the estimated basicity when considering the amount of slopping is closer to the analytical value of basicity than when not considering it. This indicates that the estimation of slopping volume in this disclosure and the estimation of slag volume according to PCT / JP2023 / 028351 were performed with high accuracy.

[0059] Therefore, by using the method disclosed herein, the amount of slopping can be estimated with high accuracy, and the amount and composition of slag remaining in the furnace can be estimated with high accuracy, making it possible to determine the amount of auxiliary materials to be added and the amount of acid to be supplied accordingly.

[0060] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above, and it is of course possible to implement it in various other forms without departing from its spirit. [Explanation of Symbols]

[0061] 20 Converter (an example of a smelting vessel) 40 Imaging device 42. Computer (an example of a control device) PF Slopping Style

Claims

1. We filmed the slopping flow flowing out of the smelting vessel. The width of the slopping flow is determined from the captured image. The sum of the calculated widths is defined as the slopping index, and the amount of slopping is estimated by multiplying the slopping index by a proportionality constant. Method for estimating the amount of slopping.

2. The method for estimating the amount of slopping according to claim 1, wherein the proportionality constant is set based on the measured amount of slopping.

3. We filmed the slopping flow flowing out of the smelting vessel. From the captured images, the width and velocity of the slopping flow are determined. The amount of slopping is estimated using the following formula (1). Method for estimating the amount of slopping. [Math 1] M: Slopping amount (kg) ρ: Bulk density of slopping flow (kg / m³) ３ ) Δt: Image capture interval (s) α: Correction parameter L: Width of the slopping flow (m) V: Flow velocity of the slopping flow (m / s)

4. A method for estimating the amount of slopping according to any one of claims 1 to 3, wherein the image is taken so as to include both sides of the refining vessel.

5. A method for estimating the amount of slopping according to any one of claims 1 to 3, wherein the refining vessel is viewed from above and photographed from different directions.

6. Using a camera, monitor the generation of a slopping flow in the refining vessel. A method for estimating the amount of slopping according to any one of claims 1 to 3, comprising: using a control device that acquires monitoring information from the aforementioned imaging device to detect the generation of the slopping flow in the refining vessel, and when the generation of the slopping flow is detected, starting to photograph the slopping flow with the imaging device.

7. The method for estimating the amount of slopping according to claim 6, wherein when a substance with a brightness value higher than a predetermined value than the background is recognized within the monitoring area of ​​the imaging device, the substance is detected as the slopping flow.

8. The method for estimating the amount of slopping according to claim 6, wherein when a substance with a brightness value higher than a predetermined value than the background is recognized in the monitoring area of ​​the imaging device with a predetermined number of pixels or more in the monitoring area, the substance is detected as the slopping flow.

9. A camera for photographing the slopping flow out of the refining vessel, A control device that performs a process to determine the width of the slopping flow from the captured image, uses the sum of the obtained widths as the slopping index, and estimates the amount of slopping by multiplying the slopping index by a proportionality constant, A system for estimating the amount of slopping.

10. A refining method comprising determining the amount and composition of slag in a refining vessel based on the amount of slopping estimated using the method for estimating the amount of slopping described in any one of claims 1 to 3, and adjusting at least one of the amount of auxiliary raw materials added and the amount of acid supplied.

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