JP4669420B2 - Blast furnace tapping temperature measuring system, blast furnace tapping temperature measuring method, and computer program - Google Patents

Description

  The present invention relates to a blast furnace tapping temperature measuring system, a blast furnace tapping temperature measuring method, and a computer program, and particularly suitable for use in measuring the temperature of hot metal flowing out from a tapping hole formed in a blast furnace. is there.

Inside the blast furnace, hot metal and molten slag are generated by a high-temperature reduction reaction, and the generated hot metal and molten slag are dropped on the bottom of the furnace to form a puddle. A tap outlet is formed in a side wall portion of the blast furnace next to the bottom of the blast furnace, and the tap outlet is filled with a mud material. When the mud material is removed using a drill or the like and the spout is opened, a mixture of hot metal and molten slag flows out. The mixture of the molten iron that has flowed out and the molten slag reaches the output and flows along the output. Thereafter, the hot metal and the molten slag are separated by a skinma formed in the middle of brewing.
As described above, the temperature of the hot metal flowing out from the outlet is determined by the state of the high-temperature heat field in the blast furnace, and is therefore an important index for judging the soundness in the blast furnace.

  Therefore, as a first conventional technique for measuring the temperature of the hot metal, there is a technique for measuring the temperature of the hot metal by immersing a so-called “disposable type” consumable thermocouple in the hot metal separated from the molten slag by the skinner. In such a technique, the measurement of the hot metal becomes intermittent due to limitations such as the cost of the disposable thermocouple and the labor of manual measurement.

  Therefore, as a second conventional technique for continuously measuring the temperature of the hot metal, a non-contact type radiation thermometer is installed at the top of the hot metal, and the temperature of the hot metal flowing through the hot metal using this radiation thermometer. There is a technique for measuring (see Patent Documents 1 and 2).

  By the way, for a while (for example, several tens of minutes) after the start of the hot metal, the hot metal heat removal by the hot metal (refractory material) is large. The temperature becomes lower than the temperature (the temperature of the hot metal drops from the tap to the tap). As described above, in the first and second conventional techniques, since the temperature of the hot metal in the brewing is measured, a temperature lower than the temperature in the brewing port is measured. Moreover, since the temperature drop of the hot metal between the tap and the tap is not constant, it is difficult to predict the temperature drop. As described above, with the first and second prior arts, it has been difficult to accurately measure the temperature of the hot metal at the spout opening.

  Therefore, as a third technique for measuring the temperature of the hot metal at the spout, a consumable metal tube-coated optical fiber thermometer is sent to the vicinity of the spout at a predetermined feed rate, and inside the hot metal flowing out of the spout. There is a technique for directly measuring the heat radiation of an iron fiber with an optical fiber thermometer and measuring the temperature of the hot metal at the spout (see Patent Document 3).

JP-A-1-233329 JP-A-1-185422 JP-A-8-82553

  However, in the third prior art described above, a lifting device that lifts and lowers the optical fiber thermometer and a device such as a measure roll for feeding the optical fiber thermometer to the hot metal are required, and the device becomes large. In addition, there is a possibility that the hot metal and molten slag at the spout may be scattered due to gas jetting from the spout, etc., so that high durability is required for the device placed near the spout.

As described above, the conventional technique described above has a problem that it is not easy to accurately measure the temperature of the hot metal at the spout.
The present invention has been made in view of such problems, and an object of the present invention is to make it possible to continuously and accurately measure the temperature of the hot metal at the tap outlet.

The blast furnace tapping temperature measuring system according to the present invention is a pixel having a density value for each pixel corresponding to the thermal radiance distribution of a region including a melt flowing out from a spout formed in the blast furnace. Imaging means for imaging as an image composed of: hot metal concentration deriving means for determining the density of an image representing the hot metal contained in the melt out of the images taken by the imaging means; and flowing out from the spout Disturbance concentration deriving means for obtaining a density of an image related to noise light emitted from the melt by illuminating the object around the melt with the radiated light of the melt and emitting reflected light, and deriving the hot metal concentration The hot metal temperature for calculating the temperature of the hot metal contained in the melt using the density of the image representing the hot metal obtained by the means and the density of the image relating to the noise light obtained by the disturbance concentration deriving means. And calculation means possess, the hot metal concentration deriving means calculates the density histogram showing the relationship between the concentration and the number of pixels for each pixel of the captured image, of the calculated density histograms, concentration in molten iron corresponding parts the concentration value at the point showing the peak histogram, and wherein Rukoto determined as the concentration of an image representing the molten iron contained in the melt.

The method for measuring the temperature of a blast furnace discharge of the present invention is such that each pixel having a density value for each pixel corresponding to the thermal radiance distribution of a thermal radiance distribution of a region including a melt flowing out from a tap outlet formed in the blast furnace. an image composed of an image pickup step for picking by the imaging means, of the image captured by the imaging step, the hot metal concentration derivation step of obtaining a density of the image representing the molten iron contained in the melt, the tapping Disturbance concentration derivation step for obtaining the density of the image related to the noise light emitted from the melt by emitting the reflected light when the object around the melt flowing out from the mouth is illuminated by the radiation light of the melt, Using the density of the image representing the hot metal obtained in the hot metal concentration deriving step and the density of the image relating to the noise light obtained in the disturbance density deriving step, the melt Possess a hot metal temperature calculation step of calculating the temperature of the molten iron contained, the hot metal concentration derivation steps, calculates the density histogram showing the relationship between the concentration and the number of pixels for each pixel of the captured image, was calculated of density histogram, a density value at the point showing the peak concentration histogram in the hot metal corresponding portions, and wherein the Rukoto determined as the concentration of an image representing the molten iron contained in the melt.

The computer program according to the present invention is configured by each pixel having a thermal radiance distribution of a region including a melt flowing out from a spout formed in a blast furnace and having a density value for each pixel corresponding to the thermal radiance. As an image, when picked up by the image pickup means, a hot metal concentration deriving step for obtaining a concentration of an image representing the hot metal contained in the melt among the picked up images, and the periphery of the melt flowing out from the spout Is obtained by a disturbance concentration deriving step for obtaining a density of an image related to noise light emitted from the melt by emitting reflected light that is illuminated by the melted light of the melt and the molten iron concentration deriving step. The temperature of the hot metal contained in the melt is calculated using the density of the image representing the molten iron and the density of the image related to the noise light obtained in the disturbance density deriving step. That the molten iron to execute the temperature calculating step to the computer, the hot metal concentration derivation steps, calculates the density histogram showing the relationship between the concentration and the number of pixels for each pixel of the captured image, of the calculated density histogram, the concentration value at the point showing the concentration histogram peaks at hot metal corresponding portions, and wherein the Rukoto determined as the concentration of an image representing the molten iron contained in the melt.

According to the present invention, when the thermal radiance distribution of the region including the melt that has flowed out from the spout is captured as an image composed of each pixel having a density value for each pixel corresponding to the thermal radiance. Among the captured images , the density value at the point where the density histogram in the hot metal equivalent portion shows a peak is obtained as the density of the image representing the hot metal contained in the melt, and the image related to the noise light emitted from the melt is obtained. Determine the concentration. And the temperature of the hot metal contained in the said melt is calculated using the density | concentration of the image showing the calculated hot metal, and the density of the image in connection with noise light.

  It is possible to identify the hot metal and the molten slag for the image of the region including the melt that has flowed out from the spout, based on the melt concentration information. Therefore, even if the hot metal and the molten slag are mixed at an unknown ratio, the density of the hot metal image can be obtained and the temperature of the hot metal can be obtained accurately.

  Also, the density of the image related to the noise light was obtained, and the temperature of the hot metal contained in the melt was calculated using the density of the image representing the hot metal and the density of the image related to the noise light. It is possible to quantitatively grasp how much the influence of the noise light is present in the image representing, regardless of the output state. Therefore, the temperature of the hot metal can be determined more easily and accurately.

Furthermore, since the temperature of the hot metal is obtained using the captured image of the region including the melt that has flowed out of the hot metal outlet, the temperature of the hot metal can be obtained without installing an apparatus near the hot metal outlet. . Thereby, it is possible to prevent the apparatus from receiving heat radiation, scattering, and the like of the hot metal and molten slag, and the environmental measures of the apparatus can be performed relatively easily.
And since the temperature of the hot metal determined as described above can be obtained continuously, it is possible to grasp the thermal condition inside the blast furnace more quickly and accurately than before, from the change and transition of the determined temperature. This can stabilize the operation of the blast furnace.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating an example of a configuration of a hot metal temperature measurement system. FIG. 1 shows only a part of the entire blast furnace 1 near the tap outlet 1a.
As shown in FIG. 1, a mixture (melt) 2 of molten iron and molten slag flows out from a tap outlet 1 a formed in a side wall portion on the side of the bottom of the blast furnace 1. The mixture 2 of the molten iron and the molten slag that has flowed out reaches the output 3 and flows along the output 3. In addition, an eaves cover 4 is formed so as to surround the eaves 3 with a gap from the eaves 1 a. In the following description, the mixture 2 of molten iron and molten slag is referred to as a tidal stream 2.

  As shown in FIG. 1, the tap stream 2 immediately after flowing out from the tap port 1 a is not shielded by the paddle cover 4. In the present embodiment, the thermal radiance distribution of the outgoing stream 2 immediately after flowing out of the outgoing outlet 1a is imaged using a monochrome CCD camera 5 from the lateral direction.

  The inventors of the present application take an exposure time (shutter speed) very short and take an image (thermal radiance distribution) of the output stream 2 flowing out from the output port 1a. It was found that the high part is separated. Such knowledge cannot be obtained by measurement with a radiation thermometer or observation with the naked eye, which has been conventionally used.

  Specifically, in this embodiment, the exposure time of the CCD camera 5 is set to 1/10000 second, and the image (thermal radiance distribution) of the outgoing flow 2 flowing out from the outgoing exit 1a shows a two-dimensional concentration distribution. The image was taken as a still image.

  By the way, the CCD camera 5 has light receiving sensitivity only for light in the wavelength band of about 0.4 μm to 0.8 μm, and the light receiving sensitivity in this wavelength band is not constant, and has a specific spectral sensitivity characteristic. Yes. Therefore, it is preferable that a wavelength selection filter that transmits only light having a certain narrow wavelength is attached to the CCD camera 5. This is because if the wavelength selective filter is used in this way, emissivity correction for calculating the temperature of the hot metal can be easily performed. Specifically, in this embodiment, an optical bandpass filter having a center transmission wavelength of 0.65 μm is attached to the CCD camera 5 as a wavelength selection filter.

  In the present embodiment, temperature calibration of the CCD camera 5 is performed in advance using a black body furnace. Here, temperature calibration refers to the relationship between black body radiance and the density of an image obtained by imaging an object having the black body radiance with the CCD camera 5 at a plurality of temperatures (for example, three or more points). Say what you want. The result of the temperature calibration is stored in the image processing device 6. Here, in the present embodiment, in addition to the calibration curve indicating the relationship between the black body radiance and the density of the image obtained by imaging the object of the black body radiance with the CCD camera 5, A density / temperature conversion formula for converting the density of an image into a temperature, which is obtained, is stored in the image processing apparatus 6 as a result of temperature calibration.

  Using the CCD camera 5 that has been temperature calibrated in this manner, an image of the tap stream 2 that flows out of the tap port 1a is captured. In this embodiment, the output flow was observed with a resolution of about 0.4 mm with the CCD camera 5 having a CCD (Charge Coupled Devices) of 640 × 480 pixels. The exposure time at the time of imaging is 1/10000 seconds as described above. Data of the captured image of the outgoing stream 2 is input to the image processing device 6. The image processing device 6 calculates a density histogram from the input output stream 2 image data.

FIG. 2 is a diagram showing an example of an image of the outgoing stream 2 (FIG. 2A) captured using the CCD camera 5 and a density histogram (FIG. 2B) in the image. The diameter of the tidal stream 2 is approximately 100 mm.
The image 21 of the outgoing stream 2 as shown in FIG. 2A is obtained by dividing the density for each pixel into density gradations on the horizontal axis and the number of pixels for each density gradation on the vertical axis. The density histogram 22 shown in FIG. In the density histogram 22 shown in FIG. 2B, the density distribution 23 that appears in the low density level portion is caused by the background image 21 a in the output 21 image 21. Two density distributions 24 and 25 appear in a portion having a high density level. Of these two density distributions 24 and 25, the density distribution 24 having the lower density level is caused by the hot metal image 21b. The density distribution 25 having the higher density level is caused by the image of the molten slag 21c.

  The reason why the concentration levels of the hot metal and molten slag do not concentrate on one point but have a distribution is as follows. First, it is conceivable that the temperature of the hot water pool in the furnace has distribution and unevenness. Secondly, the flow component that happens to be present on the surface of the tidal stream 2 when it flows out has a concentration level due to instantaneous and local temperature drop due to contact with the inner wall of the tapping outlet and the atmosphere. It is possible to go down. Third, it is conceivable that the concentration level increases due to an increase in the apparent emissivity due to the multiple reflection of the radiated light generated in the valleys of the ripples on the surface of the turbulent outflow 2.

  The ratio of the hot metal and molten slag contained in the outgoing stream 2 and the outflow amount of the outgoing stream 2 vary from moment to moment. Therefore, when the appearance of the density histogram was observed by capturing a plurality of images of the tapping flow with different tapping conditions, for example, as shown in FIG. 3, the distribution of both corresponds to the ratio of the hot metal to the molten iron slag. It was confirmed that the shape of this also changed. Specifically, in the concentration histogram 31 shown in FIG. 3A, the peak of the concentration distribution 32 caused by molten iron is larger than the peak of the concentration distribution 33 caused by molten slag, whereas FIG. In the concentration histogram 34 shown in b), the peak of the concentration distribution 36 caused by molten slag is larger than the peak of the concentration distribution 35 caused by hot metal.

In the density histogram as described above, the present inventors have obtained the following knowledge.
First, it has been clarified that the density value P _M at the peak due to hot metal in the density histogram is irrelevant to the distribution shape of the output stream 2 image.

Secondly, the relationship between the concentration value P _M at the peak caused by hot metal in the concentration histogram and the temperature of the hot metal, the immersion consumable thermocouple probe was experimentally inserted into the hot metal flow 2, and the temperature of the hot metal was determined. Examination by measuring the temperature of the molten iron increases, the density value P _M increases (image 21 becomes brighter) of the peak due to hot metal revealed.
Third, by performing emissivity correction with the spray rate of the hot metal in the visible light wavelength band observed by the CCD camera 5, the temperature of the hot metal is calculated using the concentration value P _M at the peak caused by the hot metal. It became clear that it was possible.

Fourth, the concentration value P _M at the peak due to the hot metal described above is affected by the reflected light emitted from the surrounding objects surrounding the hot metal flow 2, and thus by correcting this influence, It became clear that the temperature could be calculated more accurately. Hereinafter, the fourth knowledge will be described in detail.

FIG. 4 shows an example of the state of the reflected light emitted from the surrounding object surrounding the outgoing stream 2.
While the outgoing stream 2 is at a high temperature of 1500 ° C. or higher, the surrounding object 7 surrounding the outgoing stream 2 is at room temperature. Therefore, only the outgoing stream 2 emits the thermal radiation light 52 in the vicinity of the outgoing exit 1a.

As shown in FIG. 4, the surrounding object 7 surrounding the outgoing stream 2 is illuminated and brightened by the thermal radiation light 52 emitted from the outgoing stream 2, and emits reflected light (disturbance light) 51. At least a part of the reflected light 51 reaches the outgoing stream 2. Then, at least part of the reflected light 53 that has reached the outgoing stream 2 is reflected by the surface of the hot metal, and the reflected light 53 travels toward the CCD camera 5 as noise light. The noise light 53 is superimposed on the heat radiation light 52 emitted from the outgoing stream 2 and is taken into the CCD camera 5 as back light noise (stray light noise). Then, in the concentration histogram, the concentration value P _M at the peak due to the molten iron becomes larger than the actual concentration value P _T in the molten iron.

The outgoing flow 2a shown in FIG. 4 (a) and the outgoing flow 2b shown in FIG. 4 (b) have the same temperature and different thicknesses (flow diameters). As shown in FIG. 4B, when the outgoing stream 2b becomes thicker, the thermal radiation lights 52d to 52h emitted from the outgoing stream 2b become larger than the thermal radiation lights 52a to 52c shown in FIG. Object 7 is illuminated more brightly. Therefore, the reflected lights 51d to 51h shown in FIG. 4B are larger than the reflected lights 51a to 51c shown in FIG. 4A, and the noise light 53b captured by the CCD camera 5 is also shown in FIG. It becomes larger than the noise light 53a shown (that is, the back light noise becomes larger). Therefore, as the outgoing flow 2b becomes thicker, the back light noise increases, and the concentration value P _M at the peak due to the molten iron in the concentration histogram becomes larger than the actual concentration value P _T in the molten iron, and the measurement error also increases. .

  Further, the size of the reflected light 51 depends on the temperature of the outgoing stream 2 and the ratio between the molten iron and the molten slag in addition to the thickness of the outgoing stream 2. Therefore, the temperature of the molten iron stream 2, the ratio of the molten iron and the molten slag, and the like affect the measurement error as well as the thickness of the molten iron stream 2.

As described above, the measurement error due to back light noise is not constant and varies depending on the output process.
It is difficult to accurately obtain the hot metal temperature from the concentration value of the hot metal image 21b included in the image 21 of the molten iron flow 2 by the principle of radiation temperature measurement. As described above, since the magnitude of the back light noise varies depending on various factors such as the thickness of the outgoing stream 2, the temperature of the outgoing stream 2, and the ratio between the molten iron and the molten slag, the image 21 of the outgoing stream 2. This is because it is difficult to accurately grasp how much the backlight noise is included in the concentration value of the hot metal image 21b included in the hot metal image and correct the temperature measurement value.

Therefore, in this embodiment, the actual concentration value P _T in the hot metal is obtained as follows, and the temperature of the hot metal is obtained using the obtained concentration value P _T.
First, the image processing device 6 inputs the output stream 2 image data captured by the CCD camera 5 as described above, and calculates a density histogram from the input output stream 2 image data. Then, the image processing device 6 obtains a density value P _M at a peak caused by hot metal in the calculated density histogram.
The density distribution caused by the background in the density histogram always has almost the same shape. This is because there is no temperature change near room temperature. Therefore, in the present embodiment, the concentration value P _M at the peak caused by hot metal is obtained as follows.

First, as shown in FIG. 2, a starting point K is specified in advance for a predetermined density level at the base portion on the high density side (high luminance side) in the density distribution 23 caused by the background image 21a. Then, peak detection processing is executed in the direction from the start point K toward the high density side (high luminance side). In this peak detection process, for example, an inflection point of the number of pixels initially obtained by sequentially proceeding the process of comparing the number of pixels (frequency) at adjacent density levels is defined as a peak caused by hot metal, Processing is performed in which the density value at the peak is set to the density value P _M at the peak due to hot metal in the density histogram.

In this way, after obtaining the density value P _M at the peak due to hot metal in the density histogram, the image processing device 6 obtains the density value P _N due to the back light noise included in the image of the outgoing stream 2 (estimation). To do).
FIG. 5 is a diagram showing an example of the ambient light photometry area set for the image of the outgoing flow 2 imaged using the CCD camera 5. By using the density value of the image of the disturbance light metering area, the density value P _N by the back light noise is obtained.
FIG. 5A shows the disturbance light metering area 62 set for the image 61a of the outgoing stream 2 (the initial stage of the outgoing stream) with a relatively small flow diameter, and FIG. 5B shows a comparison of the flow diameters. The ambient light photometry area 62 set for the image 61b of the target thick outgoing flow 2 (late output late stage) is shown.

  In the present embodiment, as shown in FIGS. 5A and 5B, the disturbance light photometry area 62 is configured so that the images 61a and 61b do not overlap the molten iron images 63a and 63b and the molten slag images 64a and 64b. Is set at a predetermined position. Specifically, in the present embodiment, the ambient light metering area 62 is set near the upper end portions of the images 61a and 61b. In this embodiment, as shown in FIGS. 5A and 5B, the same disturbance light metering area 62 is set for the images 61a and 61b regardless of the state of the outgoing flow 2. Yes.

The image processing apparatus 6 calculates the average density P _A in the disturbance light metering area 62 set as described above. Then, the average concentration P _A of the ambient light metering area 62 calculated using the reflectance of hot metal R, the following equation (1), obtaining the density value P _N by the back light noise.
P _N = R × P _A (1)
Here, for the hot metal reflectivity R, a physically verified value is used. As a specific example, the reflectance R of the hot metal is about 0.6.

Next, the image processing apparatus 6 uses the density value P _M at the peak due to the hot metal in the density histogram and the density value P _N due to the back noise, and calculates the actual density in the hot metal by the following equation (2). The value P _T is obtained.
P _T = P _M −P _N (2)

Next, the image processing apparatus 6 uses the result of temperature calibration performed on the CCD camera 5 using a black body furnace (for example, the above-described concentration / temperature conversion formula), and the actual concentration value P _T in the hot metal. from calculates the temperature T _M apparent in molten iron.
As described above, in the temperature calibration of the CCD camera 5, the relationship between the black body radiance and the density of the image obtained by imaging the object having the black body radiance with the CCD camera 5 is obtained. However, actual hot metal is not a black body and has an emissivity of less than 1, and has an emissivity different from that of a black body. Therefore, the temperature T _M apparent in molten iron calculated as described above, the error due to the difference in the emissivity occurs. Therefore, in consideration of the influence of the difference in emissivity, it is preferable to perform an operation for obtaining the actual temperature T _T in the hot metal from the apparent temperature T _{M in the} hot metal.

Specifically, the relationship between the actual temperature T _T in the hot metal and the apparent temperature T _M in the hot metal is theoretically expressed by the following equation (3).
ln (ε) = C ₂ / λ · (1 / T _T −1 / T _M ) (3)
Here, ε is the emissivity of the hot metal, and λ is the observation wavelength (transmission wavelength of the wavelength selection filter). C ₂ is Planck's second constant (= 1.44 × 10 ⁴ [μm · K]). Such temperature correction calculation for emissivity is generally performed by radiation temperature measurement.
The image processing apparatus 6, (3) using the formula, determine the actual temperature T _T in the molten iron, and the like to display the temperature T _T determined to notify the user. By repeatedly executing the above processing in real time, it is possible to continuously measure the temperature of the hot metal during pouring and notify the user.
As described above, in this embodiment, the hot metal temperature measurement system is configured by using the CCD camera 5 and the image processing device 6.

Next, an example of the operation of the image processing apparatus 6 provided in the hot metal temperature measurement system will be described with reference to the flowchart of FIG.
First, in step S <b> 1, the CPU waits until an image of the output stream 2 flowing out from the output port 1 a is input from the CCD camera 5.
When the image of the output flow 2 flowing out from the output port 1a is input, the process proceeds to step S2, and a density histogram is calculated from the input image data of the output flow 2. Then, the density value P _M at the peak attributable to the hot metal in the calculated density histogram obtained by performing the peak detection process described above.

Next, in step S3, the image input in step S1, set the ambient light metering area 62, calculates the average density P _A of the ambient light metering area 62 which is set. In the present embodiment, the shape, size, and position of the ambient light photometry area 62 are determined in advance.
Next, the reference in step S4, the average concentration P _A in the ambient light metering area 62 calculated at step S3, by multiplying the reflectivity R of the molten iron, the determined density value P _N by the back light noise ((1) ).

Next, in step S5, determined in step S2, from the density value P _M at the peak attributable to the hot metal in the density histogram, calculated in step S4, by subtracting the density value P _N by back light noise, the actual in molten iron A density value P _T is obtained (see equation (2)).
Next, in step S6, the result of temperature calibration performed on the CCD camera 5 (eg, the black body radiance of a black body furnace is imaged by the CCD camera 5 and the relationship between the temperature to be measured and the image density is measured. The apparent temperature T _M in the molten iron is calculated from the actual concentration value P _T in the molten iron using the concentration / temperature conversion formula data determined in this manner. Further, by performing the emissivity correction operation using the aforementioned equation (3), determine the actual temperature T _T in the molten iron. The emissivity value is specified in advance. Time-series data of the hot metal temperature _T T, determined to display.

  Next, in step S7, it is determined whether or not a measurement end instruction has been given by the user. As a result of the determination, if the measurement end instruction is not given by the user, steps S1 to S7 are repeated until the measurement end instruction is given.

7, the temperature of the molten iron obtained by the method of this embodiment, the temperature of the molten iron were measured using an immersion consumable thermocouple probe, it was determined from the density value P _M at the peak attributable to the hot metal in the density histogram It is the figure which showed the temperature of hot metal.
Here, the temperature of the hot metal obtained from the concentration value P _M at the peak caused by the hot metal in the concentration histogram is the peak caused by the hot metal in the concentration histogram without calculating the equations (1) and (2). The apparent temperature in the hot metal is calculated from the concentration value P _M at, and the temperature of the hot metal determined by substituting the calculated temperature into the equation (3).

In FIG. 7, the solid line indicates the temperature of the hot metal determined by the method of the present embodiment, the black circle (●) indicates the temperature of the hot metal measured using the immersion consumable thermocouple probe, and the broken line indicates the concentration histogram. It shows the temperature of the molten iron obtained from the density value P _M at peak caused by hot metal.
Here, the measurement using the immersion consumable thermocouple probe is performed because the immersion consumable thermocouple probe is directly measured by immersing the immersion consumable thermocouple probe in the tap flow 2 near the tap port 1a. The reliability of the temperature is extremely high.

  As shown in FIG. 7, when the influence of the back light noise on the image is corrected and the temperature of the hot metal is obtained as in the present embodiment, the temperature of the hot metal is obtained without performing the correction. However, it is possible to obtain a temperature close to the measurement temperature (true temperature) by the immersion consumable thermocouple probe, and of course, continuous measurement is performed instead of intermittent measurement like the immersion consumable thermocouple probe. be able to.

  In the present embodiment, a personal computer equipped with an image input / output board is used as the image processing apparatus 6 that performs the above processing. The hardware configuration of the image processing device 6 is, for example, as shown in FIG.

  In FIG. 8, an image processing apparatus 6 includes a CPU 101, a ROM 102, a RAM 103, a keyboard controller (KBC) 105 of a keyboard (KB) 104, a CRT controller (CRTC) 107 of a CRT display (CRT) 106, and a hard disk ( HD) 108 and flexible disk (FD) 109 disk controller (DKC) 110 and image input / output board (PIB) 111 controller (IC) 112 are connected via a system bus 113 so that they can communicate with each other. It is said.

The CPU 101 comprehensively controls each component connected to the system bus 103 by executing software stored in the ROM 102 or the HD 108 or software supplied from the FD 109.
That is, the CPU 101 performs a control for realizing the above-described processing operation by reading a processing program according to a predetermined processing sequence from the ROM 102, the HD 108, or the FD 109 and executing it.

The RAM 103 functions as a main memory or work area for the CPU 101.
The KBC 105 controls an instruction input from the KB 104 or a pointing device (not shown).

The CRTC 107 controls display on the CRT 106.
The DKC 110 controls access to the HD 108 and the FD 109 that store a boot program, various applications, an editing file, a user file, a network management program, a predetermined processing program in the present embodiment, and the like.
The IC 112 controls input / output of image data performed with a device such as the CCD camera 5 connected to the PIB 111.

As described above, in the present embodiment, as described, to calculate the density histogram from the data of the tapping stream 2 images captured by the CCD camera 5 obtains a density value P _M at the peak attributable to the hot metal in the calculated density histogram. Then, among the image 61 of Dezukuryu 2, an average concentration P _A in the ambient light metering area 62 set in a position that does not overlap the image of the image 63 and molten slag 64 in the hot metal, the average concentration P _A obtained multiplied by the reflectance R of the molten iron to obtain the density value P _N by the back light noise. Further, from the density value P _M at the peak attributable to the hot metal in the concentration histograms, determine the actual concentration values P _T in molten iron by subtracting the density value P _N by back light noise, the actual concentration values in the molten iron obtained P _T Is used to find the temperature in the hot metal.

  As described above, the density histogram is calculated from the data of the output stream 2 imaged by the CCD camera 5, and the density distribution caused by the molten iron and the density distribution caused by the molten slag are clearly separated. Therefore, even if the hot metal and the molten slag are mixed at an unknown ratio, the temperature of the hot metal can be easily and accurately obtained.

Further, the reflectance of the molten iron is set to the average density P _A in the ambient light photometry area 62 which is set at a position in the image 61 of the molten iron flow 2 and does not overlap with the molten iron image 63 and the molten slag 64 image. multiplied by the R, since to obtain the density value P _N by back light noise, the image 64 of the image 63 and the molten slag hot metal, whether affected by back-to-light noise is how much there, regardless of the tapping state It can be grasped quantitatively. Therefore, the temperature of the hot metal can be determined more easily and accurately.

Further, the temperature of the hot metal is obtained by using the image of the tap stream 2 picked up by the CCD camera 5 disposed at a position away from the tap hole 1a without installing a device near the tap hole 1a. As a result, it is possible to prevent the apparatus from receiving heat radiation and scattering of the hot metal and molten slag, and the environmental measures of the apparatus can be performed relatively easily.
And since the temperature of the hot metal calculated | required as mentioned above can be obtained continuously, from the change and transition of the calculated | required temperature, grasping | ascertaining the thermal condition inside the blast furnace 1 more rapidly and correctly than before. And the operation of the blast furnace 1 can be made more stable.

  In the present embodiment, the resolution of the CCD camera 5 is about 0.4 mm and the exposure time is 1/10000 second. However, the resolution and exposure time of the CCD camera 5 are not limited to these. However, the resolution of the CCD camera 5 is preferably 1 mm or less, and the exposure time is preferably 1/5000 seconds or less. Thus, the reason why the resolution of the CCD camera 5 is set to 1 mm or less is to capture a linear or dotted portion having a size of about 2 mm, which exists in the details of the molten slag. The exposure time is set to 1/5000 seconds or less so that the outgoing stream 2 moving at high speed and in a turbulent state can be observed without moving the image.

  Specifically, when the resolution of the CCD camera 5 is set to 1 mm or less and the exposure time is set to 1/5000 seconds or less, for example, as shown in FIG. 92 and the peak 93 of the portion representing the molten slag clearly exist. On the other hand, if the resolution of the CCD camera 5 is set to 1 mm or less and the exposure time is not set to 1/5000 seconds or less, as shown in FIG. And the peak 93 of the part showing molten slag does not exist separately, and there is a possibility that the temperature of the hot metal cannot be obtained. Therefore, the resolution of the CCD camera 5 is preferably 1 mm or less, and the exposure time is preferably 1/5000 seconds or less.

  In this embodiment, the CCD camera 5 is used to capture the image of the outgoing stream 2, but the CCD camera 5 is not necessarily used. For example, an image pickup apparatus such as a camera using a sensor other than a CCD (for example, a CMOS sensor) as an image pickup element or a steel camera using a silver salt film can be used in place of the CCD camera 5.

Furthermore, in the present embodiment, the image of the outgoing stream 2 (thermal radiance distribution) is captured as a still image indicating a two-dimensional concentration distribution. For example, using a one-dimensional linear array camera, An image showing a dimensional density distribution may be taken, a density histogram may be calculated from the taken image showing a one-dimensional density distribution, and the temperature of the hot metal may be obtained as described above.
In addition, a one-dimensional linear array camera repeats imaging with a high-speed shutter having a short exposure time in time, and forms an image showing a two-dimensional density distribution by orthogonally crossing the camera element arrangement direction and the time direction. Alternatively, a density histogram may be calculated from the formed image showing the two-dimensional density distribution, and the temperature of the hot metal may be obtained as described above.

  Further, a beam spot imaging device that observes only one narrow point of the output stream 2 may be used instead of the CCD camera 5. Using this beam spot imaging device, imaging is repeated with a high-speed shutter having a short exposure time continuously in time, an image showing a one-dimensional density distribution in the time direction is formed, and the formed one-dimensional density distribution is shown. A density histogram may be calculated from the image, and the hot metal temperature may be obtained as described above.

  Further, as described above, it is preferable to use the wavelength selective filter because temperature calibration can be easily performed, but it is not always necessary to use the wavelength selective filter. When the wavelength selection filter is not used in this manner, the hot metal is effective from the spectral sensitivity characteristics of the imaging device, the spectral emissivity of the hot metal, and the spectral characteristics of black body radiation in the detection wavelength band of the imaging device such as the CCD camera 5. Try to find the emissivity. Specifically, within the light receiving sensitivity range of the imaging device, the emissivity of the hot metal, which is wavelength-averaged after being weighted for each wavelength by the spectral characteristics of the imaging device and the spectral characteristics of thermal radiation (black body radiation), is used. Is preferred. Further, temperature calibration may be performed using the output stream 2 itself.

In this embodiment, the peak detection process is performed using the calculated density histogram as it is. However, the density histogram is smoothed in advance, and the peak detection process is performed using the smoothed density histogram. You may make it perform. In this way, it is possible to accurately obtain the density value P _M at the peak caused by hot metal in the density histogram even when fine noise is added to the waveform of the density histogram.

Moreover, the temperature of the hot metal in the outgoing stream 2 varies in the range of about 1450 to 1600 ° C. Therefore, it is possible to predict to some extent the existence range of the density values P _M at the peak attributable to the hot metal in the density histogram. Therefore, the peak detection process may be performed within the presence range predicted in advance. In this way, the density value P _M at the peak due to the hot metal in the density histogram can be quickly obtained.

Furthermore, the position of the ambient light photometry area 62 is a position that does not overlap the images of the hot metal 63a and 63b and the images 64a and 64b of the molten slag and is within the images 61a and 61b, as shown in FIG. It is not limited to.
The size and shape of the ambient light metering area 62 may be any size as long as the average density of the ambient light metering area 62 can be appropriately determined. since obtaining the density value P _N by back light noise, the magnitude of the disturbance light metering area 62, it as much as possible is preferably large.

Furthermore, in the present embodiment, the same ambient light metering area 62 is set for the images 61a and 61b regardless of the state of the outgoing flow 2, but different ambient light metering areas depending on the outgoing state are set. You may make it set.
Further, the functions of the image processing device 6 may be shared by a plurality of devices.

(Other embodiments of the present invention)
In order to operate various devices to realize the functions of the above-described embodiments, program codes of software for realizing the functions of the above-described embodiments are provided to an apparatus or a computer in the system connected to the various devices. What is implemented by operating the various devices according to a program supplied and stored in a computer (CPU or MPU) of the system or apparatus is also included in the scope of the present invention.

  In this case, the program code of the software itself realizes the functions of the above-described embodiments, and the program code itself and means for supplying the program code to the computer, for example, the program code are stored. The recorded medium constitutes the present invention. As a recording medium for storing the program code, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

  Further, by executing the program code supplied by the computer, not only the functions of the above-described embodiments are realized, but also the OS (operating system) or other application software in which the program code is running on the computer, etc. It goes without saying that the program code is also included in the embodiment of the present invention even when the functions of the above-described embodiment are realized in cooperation with the embodiment.

  Further, after the supplied program code is stored in the memory provided in the function expansion board of the computer or the function expansion unit connected to the computer, the CPU provided in the function expansion board or function expansion unit based on the instruction of the program code Needless to say, the present invention includes a case where the functions of the above-described embodiment are realized by performing part or all of the actual processing.

  The above-described embodiments are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

It is a figure which shows embodiment of this invention and shows an example of a structure of the hot metal temperature measurement system. It is a figure showing an embodiment of the present invention and an example of an output flow image captured using a CCD camera and a density histogram in the image. It is the figure which showed embodiment of this invention and showed an example of the image of the hot metal flow when the ratio of hot metal and hot metal slag differs. It is the figure which showed embodiment of this invention and showed an example of the mode of the reflected light emitted from the surrounding object surrounding a tidal stream. It is a figure showing an embodiment of the present invention and an example of a disturbance light photometry area set for an image of the outgoing stream 2 imaged using a CCD camera. It is a flowchart which shows embodiment of this invention and demonstrates an example of operation | movement of the image processing apparatus provided in the hot metal temperature measurement system. The embodiment of the present invention shows the temperature of the hot metal determined by the method of the present embodiment, the temperature of the hot metal measured using the immersion consumable thermocouple probe, and the concentration value at the peak due to the hot metal in the concentration histogram. It is the figure which showed the temperature of the obtained hot metal. 1 is a diagram illustrating an example of a hardware configuration of an image processing device 6 according to an embodiment of the present invention. FIG. 6 is a diagram illustrating an example of a density histogram when the imaging condition is different according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Blast furnace 1a Outlet 2 Outlet flow 3 Outlet 4 Cover 5 CCD camera 6 Image processing device 21 Outlet image 22, 31, 34 Concentration histogram 23 Concentration distribution 24, 32, 35 caused by background Concentration distributions 25, 33, and 36 caused by slag Concentration distributions 51 and 53 caused by molten slag Reflected light (disturbance light)
52 Thermal Synchrotron Radiation 61 Outlet Flow Image 62 Disturbance Photometry Area 63 Hot Metal Image 64 Molten Slag Image

Claims (7)

An imaging means for imaging a thermal radiance distribution of a region including a melt flowing out from a spout formed in a blast furnace as an image composed of pixels having a density value for each pixel corresponding to the thermal radiance ; ,
Among the images taken by the imaging means, hot metal concentration deriving means for obtaining the density of the image representing the hot metal contained in the melt,
Disturbance concentration derivation for obtaining the density of the image related to the noise light emitted from the melt by emitting reflected light from an object around the melt flowing out from the spout opening. Means,
The temperature of the hot metal contained in the melt is calculated using the density of the image representing the hot metal determined by the hot metal concentration deriving means and the density of the image related to the noise light determined by the disturbance concentration deriving means. have a and hot metal temperature calculation means,
The hot metal concentration deriving means calculates a density histogram indicating the relationship between the density of each pixel of the captured image and the number of pixels, and in the calculated density histogram, the density histogram in the portion corresponding to the hot metal shows a peak. of the density value, the blast furnace tapping temperature measuring system according to claim Rukoto determined as the concentration of an image representing the molten iron contained in the melt.   The disturbance density deriving means obtains the density of an image related to noise light emitted from the melt using the density of an image in a region different from the image representing the melt among the captured images. The blast furnace discharge temperature measuring system according to claim 1.   The disturbance concentration deriving means emits from the melt by multiplying the average density of an image in a region different from the image representing the melt by the reflectance of the hot metal contained in the melt. The system for measuring the temperature of a blast furnace outlet according to claim 2, wherein the density of an image related to the noise light generated is obtained. The resolution of the imaging means is 1 mm or less;
The blast furnace tapping temperature measuring system according to any one of claims 1 to 3 , wherein an exposure time at the time of imaging in the imaging means is 1/5000 second or less. The hot metal temperature calculating means obtains in advance a density value obtained by subtracting the density of the image related to the noise light obtained by the disturbance density deriving means from the density of the image representing the hot metal obtained by the hot metal concentration deriving means. by using the result of the temperature calibration, blast furnace tapping temperature measuring system according to any one of claim 1 to 4, characterized in that to calculate the temperature of the molten iron contained in the melt. The thermal radiance distribution of the region including the melt that has flowed out from the tap hole formed in the blast furnace is captured by the imaging means as an image composed of pixels having density values for each pixel corresponding to the thermal radiance. Imaging step to
Of the images imaged in the imaging step, the hot metal concentration derivation step for obtaining the density of the image representing the hot metal contained in the melt,
Disturbance concentration derivation for obtaining the density of the image related to the noise light emitted from the melt by emitting reflected light from an object around the melt flowing out from the spout opening. Steps,
The temperature of the hot metal contained in the melt is calculated using the density of the image representing the hot metal determined in the hot metal concentration deriving step and the density of the image relating to the noise light determined in the disturbance concentration deriving step. have a and hot metal temperature calculation step,
The hot metal concentration deriving step calculates a density histogram showing the relationship between the density of each pixel of the captured image and the number of pixels, and the density histogram in the hot metal equivalent portion of the calculated density histogram shows a peak. of the density value, blast furnace tapping temperature measurement wherein the Rukoto determined as the concentration of an image representing the molten iron contained in the melt. The thermal radiance distribution of the region including the melt that has flowed out from the tap hole formed in the blast furnace is captured by the imaging means as an image composed of pixels having a density value for each pixel corresponding to the thermal radiance. Then, the hot metal concentration derivation step for obtaining the density of the image representing the hot metal contained in the melt among the captured images,
Disturbance concentration derivation for obtaining the density of the image related to the noise light emitted from the melt by emitting reflected light from an object around the melt flowing out from the spout opening. Steps,
The temperature of the hot metal contained in the melt is calculated using the density of the image representing the hot metal determined in the hot metal concentration deriving step and the density of the image relating to the noise light determined in the disturbance concentration deriving step. Let the computer execute the hot metal temperature calculation step ,
The hot metal concentration deriving step calculates a density histogram showing the relationship between the density of each pixel of the captured image and the number of pixels, and the density histogram in the hot metal equivalent portion of the calculated density histogram shows a peak. the density values, the computer program characterized Rukoto determined as the concentration of an image representing the molten iron contained in the melt.

Images