JP7189844B2 - Temperature measuring device and temperature measuring method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a technique for measuring the temperature of hot metal and slag contained in a tapped slag stream.

For the management of blast furnace operation, etc., the temperature of each of molten pig iron and molten slag contained in a tapping slag stream taken out from the tap hole of the blast furnace is measured. As a technique for measuring these temperatures, for example, there is a tapping temperature measuring device disclosed in Patent Document 1. This apparatus includes an imaging unit that captures the thermal radiance distribution of the slag flow as a target image that is composed of pixels each having a pixel value corresponding to the thermal radiance, and an image captured by the imaging unit. a setting unit for setting an evaluation region of a predetermined size in the image of the slag flow in the target image; an extraction unit for extracting a minimum pixel value in the evaluation region set by the setting unit; a temperature calculation unit for obtaining a molten iron temperature of molten iron contained in the tapping slag flow based on the extracted minimum pixel value, the extraction unit further comprising a maximum pixel value in the evaluation region set by the setting unit; and the temperature calculation unit further obtains the slag temperature of the slag contained in the tapped slag flow based on the maximum pixel value extracted by the extraction unit.

JP 2018-200199 A

According to the tapping temperature measuring apparatus disclosed in Patent Document 1, it is possible to improve the measurement accuracy of the temperatures of molten iron and molten slag. The present inventors have found a technique for improving the measurement accuracy of the temperature of molten iron and molten slag by a method different from this tapping temperature measuring device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a temperature measuring device and a temperature measuring method capable of improving the measurement accuracy of the temperature of molten iron and molten slag contained in a tapped slag flow.

A temperature measuring device according to a first aspect of the present invention includes an image generation unit that generates an image having a molten iron image showing molten iron contained in the tapped slag flow, using time-series images of the tapped slag flow; a temperature calculation unit for calculating the temperature of the molten iron contained in the tapping slag flow based on the pixel values indicated by the pixels forming the molten iron image.

The tapping slag stream is a mixture of hot metal and slag. The image generation unit generates an image having a hot metal image using the time-series images of the tapping slag flow. The temperature of the hot metal contained in the tapped slag flow is the pixel value indicated by the pixels that make up the hot metal image (the pixel value may be, for example, radiance, or a value that can be converted to radiance using predetermined calibration information). In the latter case, the pixel values are converted to radiance and the temperature is calculated using this radiance.). Therefore, in calculating the temperature of the hot metal, it is possible to avoid the influence of the temperature of the molten slag. Therefore, according to the temperature measuring device according to the first aspect of the present invention, it is possible to improve the measurement accuracy of the temperature of molten iron.

In the above configuration, the image having the hot metal image is a minimum value image, and the image generation unit obtains a minimum value of pixel values indicated by pixels of the same pixel coordinates with respect to the time-series images, generates the minimum value image in which the pixel value indicated by is the minimum value.

A minimum value image is an example of an image having a hot metal image. The reason is as follows. It is believed that the emissivity of hot metal is about 0.4 and that of slag is about 0.9 to 0.95. In the tapped slag stream, hot metal and slag are mixed together, and translucent slag is on top of the hot metal. For this reason, the emissivity of the hot metal seen from the surface of the slag stream is an apparent value. Moreover, since the thickness of the molten slag on the molten iron usually differs depending on the location on the tapping slag flow, the apparent value of the emissivity of the molten iron varies depending on the location on the tapping slag flow (molten If the influence of the slag is small, the apparent value of the emissivity of the hot metal will be small.If the influence of the slag is large, the apparent value of the emissivity of the hot metal will be large.)

This means that even if the location on the tapped slag flow is the same, the apparent value of the emissivity of the hot metal differs if the time is different when viewed on the time axis. Therefore, regarding the time-series images, the pixel values indicated by the pixels with the same pixel coordinates are not constant, but change, and the darkest pixel (the pixel with the minimum pixel value) among the pixels with the same pixel coordinates is the melted pixel. Pixels that are not affected by slag, or pixels that are least affected by slag. Therefore, the temperature calculated based on the pixel value indicated by the pixel indicates the true value of the temperature of the hot metal, or a value close to the true value. Since the pixel value indicated by each pixel of the minimum value image is the minimum value as described above, the minimum value image is likely to be an image having a hot metal image.

The above configuration further includes a judgment unit that judges, using a threshold value, the validity of the pixel values indicated by the pixels forming the hot metal image.

Gases such as smoke and water vapor are generated at the site where the slag flow flows, and time-series images of the slag flow are sometimes captured through this gas. In this case, the pixel values indicated by the pixels forming the hot metal image become smaller than the original values. If the temperature of the molten iron is calculated based on such pixel values, the measurement accuracy of the temperature of the molten iron decreases. According to this configuration, the validity of the pixel values indicated by the pixels forming the hot metal image is determined using the threshold value. Therefore, it is possible to prevent the temperature of molten iron calculated with a pixel value smaller than the original value from being adopted as the temperature of molten iron.

A temperature measurement method according to a second aspect of the present invention includes an image generating step of generating an image having a molten iron image showing molten iron contained in the tapping slag flow using time-series images of the tapping slag flow; and a temperature calculation step of calculating the temperature of the molten iron contained in the tapping slag flow based on the pixel values indicated by the pixels forming the molten iron image.

The temperature measuring method according to the second aspect of the present invention defines the temperature measuring device according to the first aspect of the present invention from the viewpoint of the method, and has the same effects as the temperature measuring device according to the first aspect of the present invention. have

ADVANTAGE OF THE INVENTION According to this invention, the measurement precision of the temperature of the hot metal and slag contained in a tapping flow can be improved.

1 is a block diagram showing the configuration of a temperature measuring device according to a first embodiment; FIG. FIG. 4 is an explanatory diagram for explaining how a tapping slag flow flows out from a tap hole of a blast furnace; It is explanatory drawing explaining the relationship between the time-series image of a tapping slag flow, and a minimum value image. FIG. 3 is a schematic diagram showing an example of images forming a time-series image; It is a schematic diagram which shows an example of a minimum value image. It is explanatory drawing explaining the relationship between the time-series image of a tapping slag flow, and a maximum value image. FIG. 6 is a schematic diagram showing a state in which an evaluation region is set in the minimum value image shown in FIG. 5; 4 is a flow chart showing the operation of the temperature measuring device in the first embodiment; It is a block diagram which shows the structure of the temperature measuring device in 2nd Embodiment. FIG. 5 is a schematic diagram showing an example of a minimum value image generated using time-series images taken in a state where smoke is generated between an imaging unit and a stream of tapping slag. FIG. 11 is a graph showing luminance changes on a straight line drawn along the outflow direction of the tapping slag stream in the minimum value images shown in FIGS. 5 and 10 ; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In each figure, the configurations denoted by the same reference numerals indicate the same configuration, and the description of the content of the configuration that has already been described will be omitted.

FIG. 1 is a block diagram showing the configuration of a temperature measuring device T1 according to the first embodiment. FIG. 2 is an explanatory diagram illustrating how the tapped slag flow PS flows out from the tap hole PH of the blast furnace SF. 1 and 2, the temperature measuring device T1 is based on time-series images of the tapping slag flow PS obtained by capturing images of the tapping slag flow PS flowing out from the tap hole PH of the blast furnace SF. is a radiation thermometer for measuring the temperature of molten iron and slag contained in tapping slag stream PS. The tapping slag stream (pig slag mixture) is a mixture of hot metal and slag (molten slag), and is discharged from the taphole PH in a hot fluid state. For example, as shown in FIG. 1, the temperature measurement device T1 includes an imaging unit 1, a control processing unit 2, a storage unit 3, an input unit 4, an output unit 5, an interface unit (IF unit) 6, Prepare.

The image capturing unit 1 is connected to the control processing unit 2 and captures time-series images of the tapping slag flow PS under the control of the control processing unit 2 . A time-series image is composed of a plurality of images captured at a plurality of times during a predetermined period (for example, 12 images captured at intervals of 5 seconds per minute). Each image constituting the time-series image may be a visible light image or an infrared image. Each image that makes up the time series is thermally imaged using calibration information, as described below.

The imaging unit 1 outputs time-series images of the slag stream PS to the control processing unit 2 . The imaging unit 1 is, for example, an imaging optical system that forms an optical image of a subject on a predetermined imaging plane. A digital camera or the like includes an area image sensor for conversion and an image processing circuit for generating image data representing an image of a subject by performing image processing on the output of the area image sensor. The imaging unit 1 is implemented by, for example, a camera that generates moving images.

For example, as shown in FIG. 2, the imaging unit 1 is appropriately disposed so as to capture an image of the tapping slag flow PS flowing from the taphole PH to the tapping trough SG provided with the tapping trough cover CV. be. Since the tapping slag flow PS flows out from the tap hole PH at a relatively high speed, the imaging unit 1 is configured to be capable of imaging at a speed corresponding to the outflow speed of the tapping slag flow PS. The imaging unit 1 may be accommodated in a housing (not shown) together with the other units 2 to 6 of the temperature measurement device T1 and configured integrally with the other units 2 to 6. However, in the first embodiment, the imaging unit 1 is configured separately from the other units 2 to 6, and the imaging unit 1 is arranged remotely from the other units 2 to 6 so as to image the slag stream PS, and is controlled by wire or wirelessly. It is communicably connected to the processing unit 2 .

Referring to FIG. 1, an input unit 4 is connected to the control processing unit 2, for example, various commands such as a command for instructing the start of temperature measurement, and temperature measurement input such as an evaluation area setting input. is a device for inputting various data necessary for the temperature measurement device T1, and includes, for example, a plurality of input switches, a keyboard and a mouse to which predetermined functions are assigned.

The output unit 5 is a device that is connected to the control processing unit 2 and outputs commands and data input from the input unit 4, the temperature measured by the temperature measuring device T1, etc., under the control of the control processing unit 2. , for example, display units (display devices) such as CRT displays, LCDs (liquid crystal display devices) and organic EL displays, and printing devices such as printers.

The IF unit 6 is, for example, a circuit that inputs and outputs data to and from an external device. , an interface circuit using the USB (Universal Serial Bus) standard, and the like. Also, the IF unit 6 may be a communication interface circuit that transmits/receives communication signals to/from an external device, such as a data communication card or a communication interface circuit conforming to the IEEE802.11 standard.

The storage unit 3 is a circuit that is connected to the control processing unit 2 and stores various predetermined programs and various predetermined data under the control of the control processing unit 2 . Various predetermined programs include, for example, a control program for controlling each unit 1, 3 to 6 of the temperature measuring device T1 according to the function of each unit, and time-series images captured by the imaging unit 1, An image generation program for generating a minimum value image (image containing hot metal image) and a maximum value image (image containing molten slag image), and setting an evaluation region of a predetermined size in each of the minimum value image and the maximum value image Using a setting program, a representative value extraction program for extracting a representative value (representative value) of pixel values indicated by pixels constituting an evaluation region set by the setting program, and a representative value extracted by the representative value extraction program, It includes a control processing program such as a temperature calculation program for calculating the temperature of the hot metal and slag contained in the tapping slag flow PS. The various predetermined data include data necessary for executing these programs. The storage unit 3 includes, for example, a ROM (Read Only Memory) that is a nonvolatile storage device, an EEPROM (Electrically Erasable Programmable Read Only Memory) that is a rewritable nonvolatile storage device, and the like. The storage unit 3 includes a RAM (Random Access Memory) or the like that serves as a working memory of the control processing unit 2 (a memory that stores data generated during execution of the various predetermined programs).

The storage unit 3 functionally includes a calibration information storage unit 31 that stores calibration information. The calibration information is a correspondence relationship between the pixel values of an image obtained by imaging a so-called blackbody furnace with the imaging unit 1 and the luminance value of the blackbody radiance of the blackbody furnace. Each of them is created in advance by photographing the black body furnace with the imaging unit 1 . Since the luminance value of the blackbody radiance is a function of temperature, the calibration information is the correspondence relationship between the pixel values of the image obtained by imaging the blackbody furnace with the imaging unit 1 and the temperature of the blackbody furnace. Become. For example, a luminance image of radiance, that is, a thermal image can be generated by converting each pixel value of each pixel in each image constituting the time-series image into each luminance value according to the calibration information. The calibration information may be stored in the calibration information storage section 31 in the form of a relational expression representing the correspondence, or may be stored in the calibration information storage section 31 in the form of a table representing the correspondence.

The control processing section 2 is a circuit for controlling the respective sections 1, 3 to 6 of the temperature measuring device T1 according to the functions of the respective sections and obtaining the temperature. The control processing unit 2 is configured including, for example, a CPU (Central Processing Unit) and its peripheral circuits. The control processing unit 2 functionally includes a control unit 21, an image generation unit 22, a setting unit 23, an extraction unit 24, and a temperature calculation unit 25 by executing the control processing program.

The control unit 21 controls the units 1, 3 to 6 of the temperature measuring device T1 according to the functions of the respective units, and controls the temperature measuring device T1 as a whole.

The image generating unit 22 uses the time-series images IM of the tapping slag flow PS to generate an image having a hot metal image 111 ( FIG. 5 ) showing hot metal contained in the tapping slag flow PS and An image is generated having a tail image (not shown) showing the contained tail. An image having a hot metal image 111 will be described.

An image having the hot metal image 111 is, for example, the minimum value image Im2 (FIG. 3). The image generator 22 obtains the minimum value of the pixel values indicated by the pixels of the same pixel coordinates for the time-series images IM, and generates a minimum value image Im2 in which the pixel values indicated by the pixels of this pixel coordinate are the minimum values. FIG. 3 is an explanatory diagram for explaining the relationship between the time-series image IM of the slag flow PS and the minimum value image Im2. Assume that the number of images Im1 constituting the time-series images IM is N (N is an integer equal to or greater than 2). Assume that the number of pixels forming each image Im1 is M (M is an integer). Pixels having the same pixel coordinates are pixels positioned in the same order in the first image Im1-1 to the Nth image Im1-N (for example, the first pixel).

In the 1st image Im1-1 to the Nth image Im1-N, the minimum value of the pixel values indicated by the 1st pixels (pixels positioned in the same order) is the pixel indicated by the 1st pixel constituting the minimum value image Im2. The minimum value of the pixel values indicated by the second pixels (pixels positioned in the same order) is the pixel value indicated by the second pixels constituting the minimum value image Im2, . . . The minimum value of the pixel values indicated by the position pixel) becomes the pixel value indicated by the M-th pixel forming the minimum value image Im2.

FIG. 4 is a schematic diagram showing an example of images Im1 forming the time-series images IM. The image Im1 includes a tapping slag flow image 101 showing the tapping slag flow PS and a background 102 . In FIG. 4, the slag flow image 101 is shown in white and one shade of gray. However, the actual tapping slag flow image 101 has a so-called marble pattern due to the difference between the emissivity of the hot metal and the emissivity of the molten slag and their mixed state. FIG. 5 is a schematic diagram showing an example of the minimum value image Im2. The minimum value image Im2 includes a molten iron image 111 showing molten iron and a background 112 . The shape of the hot metal image 111 is approximately the same as the shape of the tapping slag flow image 101 . The molten iron image 111 does not have a portion with relatively high brightness (a portion indicating molten slag), and has relatively low brightness as a whole. In FIG. 5, the hot metal image 111 is shown in one shade of gray. However, the actual hot metal image 111 is shown in a plurality of shades of gray with small density differences.

The minimum value image Im2 is an example of an image having the hot metal image 111 . The reason is as follows. It is believed that the emissivity of hot metal is about 0.4 and that of slag is about 0.9 to 0.95. The tapping slag flow PS is a mixture of hot metal and slag, and translucent slag is on top of the hot metal. Therefore, the emissivity of the hot metal viewed from the surface of the tapping slag flow PS is an apparent value. Moreover, since the thickness of the slag on the hot metal usually differs depending on the location on the tapping slag flow PS, the apparent emissivity of the molten iron varies depending on the location on the tapping slag flow PS. (If the influence of slag is small, the apparent emissivity of hot metal will be small. If the influence of slag is large, the apparent emissivity of hot metal will be large.)

This means that even if the point on the tapped slag flow PS is the same on the time axis, the apparent value of the emissivity of the hot metal differs if the time differs. Therefore, regarding the time-series images IM, the pixel values indicated by the pixels with the same pixel coordinates are not constant but change, and the darkest pixel (the pixel with the minimum pixel value) among the pixels with the same pixel coordinates is It is the pixel that is not affected by the slag, or the pixel that is least affected by the slag. Therefore, the temperature calculated based on the pixel value indicated by the pixel indicates the true value of the temperature of the hot metal, or a value close to the true value. Since the pixel value indicated by each pixel of the minimum value image Im2 is the minimum value as described above, the minimum value image Im2 is likely to be an image having the hot metal image 111. FIG.

The image having the hot metal image 111 is not limited to the minimum value image Im2. explain in detail. Regarding the time-series image IM, if an image having the hot metal image 111 can be generated even with the second or third smallest value among the pixels of the same pixel coordinates, this image may be used. Further, with respect to the time-series image IM, among the pixels of the same pixel coordinates, the pixels showing the pixel values within a lower constant ratio are extracted, and the molten iron image 111 is obtained by the average value or the median value of the pixel values shown by the extracted pixels. This image may be used as long as it can generate an image with

An image having a slag image will be described. This image is, for example, the maximum value image Im3 (FIG. 6). The image generator 22 obtains the maximum value of the pixel values indicated by the pixels of the same pixel coordinates for the time-series images IM, and generates a maximum value image Im3 in which the pixel values indicated by the pixels of this pixel coordinate are the maximum values. FIG. 6 is an explanatory diagram for explaining the relationship between the time-series image IM of the slag flow PS and the maximum value image Im3. FIG. 6 differs from FIG. 3 in that the minimum value image Im2 is shown as the maximum value image Im3. In the description of the minimum value image Im2 described above, replacing the "minimum value" with the "maximum value" leads to the description of the maximum value image Im3, so a detailed description of FIG. 6 is omitted.

The maximum value image Im3 is an example of an image having a slag image. The reason is as follows. As described above, the tapping slag flow PS is a mixture of hot metal and slag, and translucent slag is on top of the hot metal. At locations where the slag on the hot metal is thin, the influence of the molten iron is large, so the temperature of the slag calculated based on the pixel values at that location is considerably lower than the true value. On the other hand, at locations where the molten slag on the hot metal is thick, there is no effect of the molten iron, or the effect is small. , close to the true value.

When viewed on the time axis, there are times when the influence of hot metal is large and times when the influence of hot metal is small even at the same point on the tapped slag flow PS. Therefore, regarding the time-series image IM, the brightest pixel (the pixel with the maximum pixel value) among the pixels with the same pixel coordinates is the pixel that is not affected by hot metal, or the pixel that is least affected by hot metal. be. Therefore, the temperature calculated based on the pixel value indicated by the pixel indicates the true temperature of the slag, or a value close to the true temperature. Since the pixel value indicated by each pixel of the maximum value image Im3 is the maximum value as described above, the maximum value image Im3 is likely to be an image having a slag image.

An image having a slag image is not limited to the maximum value image Im3. explain in detail. Regarding the time-series image IM, if an image having a slag image can be generated even with, for example, the second or third largest value among the pixels of the same pixel coordinates, this image may be used. In addition, regarding the time-series image IM, among the pixels of the same pixel coordinates, the pixels showing the pixel values within the upper fixed ratio are extracted, and the slag image is also obtained by the average value or the median value of the pixel values shown by the extracted pixels. This image may be used as long as it can generate an image with

Referring to FIG. 1, setting unit 23 sets evaluation regions ROI (FIG. 7) of a predetermined size in minimum value image Im2 and maximum value image Im3. Since the method of setting the evaluation region ROI is the same for the minimum value image Im2 and the maximum value image Im3, the minimum value image Im2 will be described as an example. FIG. 7 is a schematic diagram showing a state in which the evaluation region ROI is set in the minimum value image Im2 shown in FIG. For example, the setting unit 23 may output the minimum value image Im2 to the output unit 5, receive a setting operation by the user at the input unit 4, and set the evaluation region ROI in the minimum value image Im2. Alternatively, the setting unit 23 may automatically set the evaluation region ROI in the minimum value image Im2, for example. More specifically, for example, the setting unit 23 first detects edges of the hot metal image 111 in the minimum value image Im2 by using an edge filter, thereby extracting the hot metal image 111 . Then, the setting unit 23 sets an evaluation region ROI within the extracted hot metal image 111 . For example, the temperature of the tapping slag flow PS is measured for the purpose of operation management of the blast furnace SF, and the viewpoint that the imaging of the tapping slag flow PS is hindered by smoke, etc., generated as the distance from the taphole PH increases. Therefore, the setting unit 23 sets the evaluation region ROI at a position in the hot metal image 111 where the effects of slag accumulation, smoke, etc. near the taphole PH are as small as possible. The size of the evaluation region ROI is appropriately set using a plurality of samples. A square or rectangle having a length of 3 or about 1/2 is set.

Referring to FIG. 1 , extraction unit 24 extracts a representative value of pixel values indicated by pixels forming evaluation region ROI set by setting unit 23 . In the case of the minimum value image Im2, the representative value is, for example, the minimum value of the pixel values, the average value of the pixel values, the median value of the pixel values, or the lower fixed percentage of the pixel values in all the pixels forming the evaluation region ROI. Average value. The average value of the pixel values of the lower constant percentage is the average value of the pixel values of the lower constant percentage (for example, the lower 5%) among the pixel values of all the pixels forming the evaluation region ROI. In the case of the maximum value image Im3, the representative value is, for example, the maximum value of the pixel values, the average value of the pixel values, the median value of the pixel values, or the pixel values of a certain percentage of the top pixels in all the pixels that make up the evaluation region ROI. Average value. The average value of pixel values of a certain upper percentage is the average value of pixel values of a certain upper percentage (for example, the top 5%) among the pixel values of all the pixels forming the evaluation region ROI.

Note that the extraction unit 24 may extract the representative value without using the evaluation region ROI. For example, the extraction unit 24 may extract the hot metal image 111 from the minimum value image Im2 and extract the representative value using the pixel values of all the pixels forming the hot metal image 111. A plurality of pixels may be randomly selected from all the pixels, and the pixel values indicated by these pixels may be used to extract the representative value. For example, the extraction unit 24 may extract the slag image from the maximum value image Im3 and extract the representative value using the pixel values of all the pixels forming the slag image. A plurality of pixels may be randomly selected from all the pixels, and the pixel values indicated by these pixels may be used to extract the representative value.

The temperature calculation unit 25 uses the representative values extracted by the extraction unit 24 to obtain the temperatures of the hot metal and slag contained in the tapped slag flow PS. More specifically, the temperature calculator 25 converts the representative value (the representative value indicates the radiance) of the evaluation region ROI set in the molten iron image 111 into a temperature, and calculates this temperature as the temperature of the molten iron. Similarly, the temperature calculation unit 25 converts the representative value (the representative value indicates the radiance) of the evaluation region ROI set in the slag image (not shown) into temperature, and calculates this temperature as the temperature of the slag. do. In this way, the temperature calculation unit 25 calculates the temperature of the hot metal contained in the tapping slag flow PS based on the pixel values indicated by the pixels forming the molten iron image 111, and calculates the temperature of the pixels forming the molten slag image 111. The temperature of slag contained in the tapped slag flow PS is calculated based on the pixel value indicated by .

As described above, the temperature of hot metal is calculated based on the pixel values indicated by the pixels forming the hot metal image 111 . Therefore, in calculating the temperature of the molten iron, it is possible to avoid the influence of the temperature of the molten slag, so it is possible to improve the measurement accuracy of the temperature of the molten iron. Further, the temperature of the molten slag is calculated based on the pixel values indicated by the pixels forming the slag image. Therefore, in calculating the temperature of the molten slag, it is possible to avoid the influence of the temperature of the molten iron, so that the measurement accuracy of the temperature of the molten slag can be improved.

These control processing unit 2, storage unit 3, input unit 4, output unit 5, and IF unit 6 can be configured by, for example, a desktop-type or node-type computer.

Next, operation of the temperature measuring device T1 in the first embodiment will be described. FIG. 8 is a flow chart showing this operation. Referring to FIGS. 1, 2 and 8, when temperature measuring device T1 is powered on, it initializes each necessary part and starts its operation. By executing the control processing program, the control processing unit 2 is functionally configured with a control unit 21 , an image generation unit 22 , a setting unit 23 , an extraction unit 24 and a temperature calculation unit 25 .

The control processing unit 2 controls the imaging unit 1 to capture time-series images IM of the tapping slag flow PS flowing out from the tap hole PH, and acquires the time-series images IM (S11).

The image generation unit 22 generates a minimum value image Im2 and a maximum value image Im3 using the time-series images IM obtained in process S11 (S12).

The setting unit 23 sets an evaluation region ROI for each of the minimum value image Im2 and the maximum value image Im3 generated in process S12 (S13).

The extraction unit 24 extracts the representative value of the evaluation region ROI set in process S13 (S14). There are two representative values. One is the representative value of the evaluation region ROI set in the minimum value image Im2, and the other is the representative value of the evaluation region ROI set in the maximum value image Im3.

The temperature calculator 25 uses the representative values extracted in step S14 to calculate the temperature of each of the hot metal and molten slag contained in the tapping slag flow PS (S15).

The control unit 21 controls the output unit 5 to output the temperatures of the hot metal and molten slag calculated in step S15 from the output unit 5 (S16), and terminates the process. Note that the control unit 21 may output the calculated temperatures of the hot metal and molten slag from the IF unit 6 to an external device, if necessary.

Each of the above-described processes for calculating the temperature of the molten iron and slag is repeatedly executed at predetermined time intervals during operation of the blast furnace SF, and the temperature of the molten iron and slag contained in the tapped slag flow PS is is monitored.

The second embodiment will be described with a focus on differences from the first embodiment. FIG. 9 is a block diagram showing the configuration of the temperature measuring device T2 according to the second embodiment. The control processing unit 2 further includes a determination unit 26 . The determining unit 26 determines the validity of the pixel values indicated by the pixels forming the hot metal image 111 included in the minimum value image Im2 using a threshold. Further, the determining unit 26 determines the validity of the pixel values indicated by the pixels forming the slag image included in the maximum value image Im3 using a threshold value.

Referring to FIG. 2, gas such as smoke or water vapor is generated at the site where the tapping slag flow PS flows, and the imaging unit 1 captures time-series images IM of the tapping slag flow PS through this gas. I have something to do. The gas is a factor that attenuates the radiant energy emitted from the tapping slag stream PS. Therefore, if this gas exists between the imaging unit 1 and the tapped slag flow PS, the region overlapping the gas in the tapped slag flow image 101 of each image forming the time-series image IM is a pixel value becomes smaller. As a result, in the hot metal image 111 of the minimum value image Im2, the pixel values of the regions overlapping with the gas are small. This is explained in FIG.

FIG. 10 is a schematic diagram showing an example of the minimum value image Im2 generated using the time-series images IM captured in a state where smoke is generated between the imaging unit 1 and the tapped slag stream PS. . The hot metal image 111 has different overall brightness between the tap hole side portion 111a and the tapping trough side portion 111b. The tap trough side portion 111b is darker than the tap hole side portion 111a. This is because the portion 111b on the tapping trough side overlaps with the gas. Therefore, the hot metal temperature calculated based on the pixel values indicated by the pixels forming the tapping trough side portion 111b is lower than the actual hot metal temperature. If the temperature of the molten iron is calculated based on such pixel values, the measurement accuracy of the temperature of the molten iron decreases.

The same can be said for the temperature of the molten slag calculated using the slag image (not shown) of the maximum value image Im3.

FIG. 11 is a graph showing changes in luminance on a straight line drawn along the outflow direction of the tapping flow PS in the minimum value image Im2 shown in FIGS. The horizontal axis is the distance represented by the number of pixels. The vertical axis represents brightness represented by pixel values. The tapping image shown in FIG. 5 has a small brightness fluctuation range. On the other hand, the tapping image shown in FIG. 10 has a significant drop in brightness at a distance of about 140. As shown in FIG. This indicates that the distance before about 140 is the tap hole side portion 111a, and the distance after about 140 indicates the tapping trough side portion 111b.

The pixel values of the hot metal image 111 shown in FIG. 5 and the tap hole side portion 111a shown in FIG. 10 are substantially the same. The tapping trough side portion 111b shown in FIG. 10 has a smaller pixel value than the molten iron image 111 shown in FIG. 5 and the taphole side portion 111a shown in FIG. That is, the hot metal image 111 (for example, the portion 111b on the tapping trough side) when smoke is generated and affected by this is the same as the hot metal image 111 (for example, the hot metal image shown in FIG. 5) when smoke is not generated. image 111) and the hot metal image 111 (for example, the portion 111a on the taphole side) when smoke is generated but is not affected by the smoke, the pixel values indicated by the pixels constituting the hot metal image 111 are small. Therefore, by using the threshold value, the effectiveness of the pixels forming the hot metal image 111 can be determined. explain in detail.

For example, based on FIGS. 5 and 10, the operator determines a threshold value for determining whether or not the pixel value indicated by the pixels forming the hot metal image 111 is smaller than the original value due to smoke. The determination unit 26 determines the validity of the pixel values indicated by the pixels forming the hot metal image 111 between the process S14 and the process S15 shown in FIG. That is, when the representative value of the pixel values indicated by the pixels forming the evaluation region ROI set in the hot metal image 111 of the minimum value image Im2 is equal to or greater than the threshold value, the determination unit 26 determines that the pixels forming the hot metal image 111 indicate Validate pixel values. The temperature calculator 25 calculates the temperature of the hot metal using the representative value.

On the other hand, when the representative value is smaller than the threshold value, the determination unit 26 denies the validity of the pixel values indicated by the pixels forming the hot metal image 111 . In this case, for example, any one of the following (1), (2), and (3) can be considered.

(1) The minimum value image Im2 having this hot metal image 111 is excluded from the hot metal temperature measurement target.

(2) The setting unit 23 moves the position of the evaluation region ROI, and the determination unit 26 performs determination processing using a threshold for the representative value of the pixel values indicated by the pixels forming the evaluation region ROI after movement. do.

(3) The temperature calculator 25 calculates the temperature of the hot metal using a representative value smaller than the threshold, but adds an error flag to this temperature.

Similarly, the determination unit 26 determines the validity of the pixel values indicated by the pixels forming the slag image using a threshold value.

101 tapping slag flow image 102 background 111 hot metal image 111a taphole side portion 111b tapping trough side portion 112 background IM time-series image Im1 image Im2 constituting time-series images minimum value image (image with hot metal image)
Im3 maximum intensity image (image with slag image)
ROI evaluation area T1, T2 Temperature measuring device SF Blast furnace PH Tap hole CV Tap iron trough cover SG Tap trough PS Tapping slag flow

Claims (3)

an image generation unit for generating an image having a hot metal image showing molten iron contained in the tapping slag flow, using time-series images of the tapping slag flow;
a temperature calculation unit that calculates the temperature of the molten iron contained in the tapping slag flow based on the pixel values indicated by the pixels forming the molten iron image,
The image having the hot metal image is a minimum value image ,
The image generation unit obtains a minimum value of pixel values indicated by pixels having the same pixel coordinates with respect to the time-series images, and generates the minimum value image in which the pixel values indicated by the pixels having the pixel coordinates are the minimum values. ,
Temperature measuring device. further comprising a determining unit that determines, using a threshold value, the validity of the pixel values indicated by the pixels forming the hot metal image;
The temperature measuring device according to claim 1. an image generation step of generating an image having a hot metal image showing hot metal contained in the tapping slag flow, using time-series images of the tapping slag flow;
a temperature calculation step of calculating the temperature of the molten iron contained in the tapping slag flow based on the pixel values indicated by the pixels forming the molten iron image;
The image having the hot metal image is a minimum value image ,
The image generating step obtains a minimum value of pixel values indicated by pixels having the same pixel coordinates with respect to the time-series images, and generates the minimum value image in which the pixel values indicated by the pixels having the pixel coordinates are the minimum values. ,
temperature measurement method.

Images