JPH1025503A - Method for measuring dropping speed of charged material in blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the dropping speed of charged material over the whole zone in a furnace by sequentially picking up the surface of the charged material piled in the blast furnace in a fixed visual field having suitable inclination and executing a picture processing to the picked-up pictures. SOLUTION: A video camera 3 is fitted near the furnace top of the blast furnace 1 so as to catch a part of the surface of the charged material 10 piled in the furnace in the fixed visual field having suitable inclination to the vertical direction. The image pickup result of the video camera 3 is processed in an image processing part 4 and the dropping speed of the charged material 10 is measured based on the variation of the image pickup result with time. The charged material 10 piled in the furnace 1 is gradually lowered as the progress of reaction in the furnace and C point on the surface of the charged material 10 is shifted to C' point. In the case of picking up this shifting state with the video camera 3, this shifting is displayed as the shift of each point in the suitable direction in the visual field. This shifting quantity corresponds to the dropping quantity of the charged material 10. The measured dropping speed can be used to correctly control the charging timing of the charged material 10 and the operational conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring, in real time, a descent speed of a charge deposited in a blast furnace during operation of a blast furnace for iron making, and an apparatus used for carrying out the method.

[0002]

2. Description of the Related Art A blast furnace is operated in such a manner that raw materials for a blast furnace mainly composed of coke and iron ore are charged into a furnace and deposited over substantially the entire height, and hot air is continuously supplied from a tuyere at a lower part of the blast furnace. The hot air is brought into countercurrent contact with the charge to be deposited in the furnace, and a predetermined furnace reaction (drying, reduction, melting, burning, etc.) is generated at each height position. The lower tap hole is opened at an appropriate timing, and the hot metal stored in the furnace bottom is taken out (tapping) procedure.

[0003] The charge accumulated in the furnace is gradually reduced with the progress of the furnace reaction occurring in the lower part.
It is necessary to replenish appropriately during operation, and this replenishment is performed in batches at predetermined time intervals by a charging device mounted on the upper part (furnace top) of the blast furnace.

[0004] For stable operation of the blast furnace, it is important that the charges are charged as uniformly as possible in the circumferential direction in the furnace. The charging device communicates with the inside of the furnace through a charging port that is opened on substantially the entire surface of the furnace top, and a pressure equalizing chamber maintained at a pressure substantially equal to the inside of the furnace, and the charging port can be freely opened and closed from below. A bell-shaped cover member (bell) for covering, a predetermined amount of the charge obtained by weighing is introduced into the pressure equalizing chamber, and is deposited on the upper part of the bell; The charging inlet is opened in an annular shape, and the charged material is dropped into the furnace from the entire circumference of the opening, thereby satisfying the above-mentioned requirement for uniform charging.

[0005] Further, in order to realize a stable operation of the blast furnace, it is important to always keep an appropriate amount of charges in the furnace. As described above, the amount of the charged material that accumulates in the blast furnace decreases as the reaction in the furnace progresses. However, it is necessary to cause a new charge to be charged at an appropriate timing.

Conventionally, a weight is attached to the tip of a measuring rod or a measuring chain suspended from the furnace top, and the weight is brought into contact with the surface of the furnace interior to reduce the amount of the charged material. A method of measuring the degree of reduction of the charged object by detecting the surface level descent through the accompanying descent of the weight is generally adopted, and the measurement result is determined by the charging timing of the charged object. Is used to optimize

[0007]

However, the surface level of the charge that can be measured by the above-described measuring method is a local surface level at the contact position of the weight, and the charge level in the entire area in the furnace is measured. There is a problem that it is not possible to know the amount of decrease in the object. This problem can be improved by arranging a plurality of measuring rods or measuring chains having the weight at the tip in the circumferential direction and examining the surface level at each position. There is a problem that it is difficult to know the degree of decrease in the load in the entire area, and that a large amount of labor is required for maintenance work for maintaining good operation of the plurality of scale bars or scale chains.

On the other hand, since the charge deposited in the furnace falls as the reaction in the furnace proceeds as described above, the state of the fall is used as a monitor of the state of the furnace which cannot be observed. This can help optimize the conditions.
However, the conventional measuring method described above is intended to detect the surface level of the charge, and cannot know the descending speed of the charge, so that it is difficult to use the method as a monitor of the furnace state that changes sequentially.

The present invention has been made in view of such circumstances, and it is possible to accurately measure the descent speed of a charge deposited in a blast furnace over the entire area of the furnace, and to adjust the charging timing of the charge. Another object of the present invention is to provide a method for measuring a descent speed of a blast furnace internal charge, which can be used for optimizing operating conditions, and an apparatus used for implementing the method.

[0010]

According to a first aspect of the present invention, there is provided a method for measuring a descent speed of a charge inside a blast furnace, the method comprising measuring a descent speed of a charge deposited in the blast furnace as the reaction in the furnace proceeds. In, the surface of the charge deposited in the blast furnace is sequentially imaged in a fixed visual field having an appropriate inclination with respect to the vertical direction, based on the temporal change of the imaging result, the descent speed It is characterized by calculating.

A method for measuring a descent speed of a blast furnace interior charge according to a second invention is the method according to the first invention, wherein a plurality of the imaging results obtained at a time interval are used to extract a region of interest from one imaging result. A region corresponding to the region of interest is searched from another imaging result, a moving amount of the region from the region of interest is obtained in the fixed field of view, and the descent speed is calculated from the moving amount and the time. It is characterized by the following.

[0012] In a third aspect of the present invention, in the method for measuring a descending speed of a blast furnace interior charge according to the second aspect, the one image pickup result is subjected to image processing by one or more image processing methods prepared in advance. The noted area is extracted from the processed image on which the image processing has been performed.

According to a fourth aspect of the present invention, there is provided an apparatus for measuring a descending speed of a charge in a blast furnace, wherein the charge deposited in the blast furnace is descended as the reaction in the furnace proceeds. Imaging means for imaging the surface of the charge to be deposited in a fixed field of view having an appropriate inclination with respect to the vertical direction, a memory for sequentially storing imaging results of the imaging means, and an image stored in the memory. It is characterized by comprising a comparing means, and a calculating means for calculating the descent speed based on the comparison result of the means.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the means for comparing images stored in the memory includes one or more image processing means prepared in advance, and Means for extracting a region of interest from a processed image on which image processing has been performed by the processing unit, and means for searching for a region corresponding to the region of interest from another stored image,
A region corresponding to the region of interest is searched from another stored image, and the region of interest is compared with the region corresponding to the region of interest.

In the present invention, an image pickup means such as a video camera is provided so as to face the surface of the charge deposited in the blast furnace, and the image pickup means sets the surface in a fixed visual field inclined with respect to the vertical. To sequentially capture images. Since the image obtained by such imaging changes in accordance with the movement of the surface accompanying the lowering of the load, the state of the lowering of the load can be determined by examining the temporal change of the imaging result. You can know including.

More specifically, a plurality of imaging results obtained at a time interval, that is, images obtained by imaging in the fixed field of view are examined, and one image can be easily distinguished from other parts. A region is extracted as a region of interest, and in other images, a corresponding region corresponding to the region of interest is searched for using an appropriate pattern matching method, and the amount of movement between these regions in the fixed visual field, The descent speed is calculated using the difference between the acquisition times of the used imaging results.

When the above-mentioned region of interest is extracted, a plurality of image processing means such as a spatial filtering process, a binarization process, a density integration process, a labeling process, and a circumscribed rectangle measurement process are prepared in advance, and the present invention is applied to the present invention. When the apparatus is installed or each time the apparatus is started up, the operator can select one of the plurality of image processing units based on the state of the processed image obtained by processing the captured image by combining one or more image processing units. Select the necessary image processing means from. Further, one or a plurality of image processing means selected based on conventional experience may be set in advance. Then, image processing is performed using the image processing means, and after performing the above-described sharpening of the imaging result, noise removal, enhancement of contrast, and the like, a region of interest is extracted from the processed image.

The imaging means is positioned near the charging device in the upper part of the blast furnace so as to include a part of the surface of the charge deposited in the furnace in a visual field inclined with respect to the central axis of the blast furnace. A video camera can be used.
However, since the inside of the furnace top to be imaged is shielded from the outside world and the amount of light is insufficient, it is desirable to use a night vision camera as the imaging means.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing the embodiments. FIG. 1 shows a method of measuring the descent speed of the blast furnace interior charge according to the present invention (hereinafter referred to as the present method).
FIG. 4 is a block diagram schematically showing the state of implementation.

In the figure, reference numeral 1 denotes a blast furnace showing the upper part, and a furnace interior material such as coke and iron ore is placed on the furnace top of the blast furnace 1.
Ten charging devices 2 are connected in series. The illustrated charging device 2
Is a two-layer type having a first pressure equalizing chamber 20 communicating with the inside of the furnace through a charging port opened substantially on the entire lower part, and a second pressure equalizing chamber 21 connected to the upper part thereof. A first pressure equalizing chamber
A large bell 22 connects the charging port connecting the blast furnace 1 with 20
A communication part between the first and second pressure equalizing chambers 20 and 21 is formed by a small bell 23.
Thereby, each is configured to be openably and closably covered from below.

The large bell 22 and the small bell 23 are individually lifted and lowered by the operation of a lifting device (not shown), and the charging opening at the furnace top of the blast furnace 1 is closed as shown by the rise of the large bell 22.
When the large bell 22 descends as shown by the broken line in the figure,
It is designed to be open in a ring around it.
The communication between the first and second pressure equalizing chambers 20 and 21 is also a small bell 23.
It is opened and closed in the same way by raising and lowering.

The charge 10 into the blast furnace 1 is weighed by a weighing device (not shown) and first introduced into a second equalizing chamber 21.
As the small bell 23 descends, it falls into the first pressure-equalizing chamber 20 and deposits on the large bell 22 at the ascending position.
In accordance with the descent of 22, the charge is charged into the blast furnace 1 through the charging opening that opens in an annular shape, and is deposited in the blast furnace 1.
Drops on 10 and accumulates.

The charge 10 charged in the furnace of the blast furnace 1 is deposited at a position below the periphery of the large bell 22 so as to have a uniform swelling over the entire circumference, as shown in the figure. In the vicinity of the furnace top of the blast furnace 1, a video camera 3 as an imaging means has a part of the surface of the charge 10 deposited in the furnace of the blast furnace 1 as described above and has an appropriate inclination with respect to the vertical direction. Mounted to capture within a fixed field of view.

The video camera 3 is fixed to the outside of the blast furnace 1 for protection from hot air and high pressure inside the blast furnace 1 and faces the inside of the blast furnace 1 through a heat-resistant imaging window (not shown). Are positioned so as to include the surface of the charge 10 in the fixed visual field described above. Moreover, it is also possible to house it in a light-transmitting capsule having high heat resistance and install it in the blast furnace 1. Further, the inside of the blast furnace 1 to be imaged is in a state of insufficient light quantity, which is extremely small due to interruption from the outside world, and it is difficult to take in external light and increase the light quantity by installing internal lighting. It is desirable to use a night vision camera capable of imaging in a dark place. And
The imaging by the video camera 3 is always performed.

The image pickup result obtained by the video camera 3 is subjected to image processing by an image processing section 4 using a computer. This processing may be performed by software or hardware. The image processing unit 4 includes a frame memory 40, an area extraction unit 41, a search unit 42, and an area memory 43.

In the frame memory 40, the imaging results obtained by the video camera 3 are stored a plurality of times at predetermined time intervals. The region extracting unit 41 includes a plurality of image processing units 41
a and an attention area setting unit 41b.

FIG. 2 is a functional block diagram of the region extracting unit 41. The image processing means 41a performs a spatial filtering process which is a product-sum operation between a pixel of interest on an image and its neighboring region and a spatial filter table. A spatial filtering processing unit 411 and a binarization processing unit 412 that compares the grayscale image with a threshold value for each pixel and binarizes the image to “0” or “1”
And a density integration processing unit 413 for projecting the gray value of each pixel on the X-axis and the Y-axis to calculate the distribution of the aggregated values. A labeling processing unit 414 that performs a labeling process for numbering sequentially and a measurement processing unit 415 that measures a circumscribed rectangle in the processed image on which the labeling process has been performed are provided.

When the image processing unit 4 is installed or each time the image processing unit 4 is started, the operator selects one image processing unit or a plurality of image processing units appropriately combined from the above-described plurality of image processing units. A means is selected, the picked-up image is image-processed by the selected image processing means, and the obtained processed image having the sharpest image is determined in advance as an image processing means to be used.

For example, if the image state of the imaging result is unclear, the image processing means is selected to perform the binarization processing after the spatial filtering processing, and then perform the density integration processing or the labeling processing and the measurement processing. . Further, when the image state of the imaging result is good, the particles are clearly seen, the contrast is good, and the image has little density unevenness,
Without performing the spatial filtering process, a binarization process and a density integration process or a binarization process, a labeling process, and a circumscribed rectangle measurement process are selected. Further, depending on the image state, the image processing means is selected so as to perform the density integration processing without performing the binarization processing after the spatial filtering processing.

FIGS. 3 and 4 show examples of image processing in the area extracting section 41. FIG. FIG. 3 shows an example of image processing in which a spatial filtering process, a binarization process, and a density integration process are selected from the image processing means 41a and the image processing is performed on the imaging result.

FIG. 3A shows a captured image A obtained from the frame memory 40 for the first time, that is, the image capturing result immediately after the loaded object 10 is loaded. For the captured image A,
First, the spatial filtering unit 411 performs a spatial filtering process. FIG. 3B shows a processed image on which a spatial filtering process has been performed. In this example, a differential process has been performed, and a line or edge having a high density in the captured image A is emphasized. .

Next, the processed image (b) is further subjected to a binarization process by a binarization processing section 412, and a binarized image of only a line or an edge having a high density (FIG. 3 (c)). Create

Then, for the binary image (c),
The density integration unit 413 performs density integration processing to roughly grasp the presence of a region to be noted. FIG. 3D shows a processed image on which the density integration processing has been performed. The area is separated into a narrow area and a wide area on the X axis, and only one area is captured on the Y axis. .

Then, as shown in FIG. 3 (e), the areas of the two separated regions are obtained, and the larger one is determined as the region of interest B which is clearly distinguishable from the other portions and which is easy to identify. And sets the selected attention area B in the attention area setting unit 41b.

FIG. 4 shows an example of image processing in which spatial filtering processing, binarization processing, labeling processing, and measurement processing are selected and image processing is performed, and (a), (b), and (c) in the figure.
Shows a processed image by the same means as in FIG.

As described above, the captured image A shown in FIG. 4A is first subjected to spatial filtering (FIG. 4B) and then subjected to binarization. Then, a labeling processing unit 414 performs labeling processing on the image (FIG. 4C) on which the binarization processing has been performed. FIG. 4F shows a processed image on which the labeling process has been performed.
Numbering is performed as in the case of the two divided connection areas. For this label image (f), a measurement processing unit
At 415, the maximum X coordinate and Y coordinate and the minimum X coordinate and Y coordinate of each connected region on the label image (f) are obtained, and a measurement process for measuring the area of a circumscribed rectangle of each connected region is performed.
FIG. 4G shows a processed image on which the measurement processing has been performed.

From the processed image (g) on which the image processing has been performed as described above, the circumscribed rectangle having the larger area is extracted as the attention area B, and the attention area setting section 41b sets the attention area.

The image processing performed by the image processing means 41a is not limited to the spatial filtering, binarization, density integration, labeling, and circumscribed rectangle measurement. Further, the spatial filtering unit 411 may perform not only the differential processing but also processing such as smoothing and morphology, and these processings are also effective for extracting the attention area. Further, in the present embodiment, when the image processing unit 4 is installed or every time the image processing unit 4 is started, the operator selects from among the plurality of image processing units,
One image processing means or a plurality of image processing means appropriately combined is selected, and the captured image is subjected to image processing by the selected image processing means, and the obtained processed image having the sharpest image should be used. Although the processing means is determined in advance, the present invention is not limited to this, and only necessary image processing means may be set in advance based on past experience. Further, it goes without saying that the selection of the image processing means by the operator may be performed at an appropriate timing after the image processing unit 4 is started.

As described above, the image of the region of interest B that has been set is a specific point indicating its position, for example, as shown in FIG.
The coordinate value (X ₁ , Y ₁ ) of the upper left corner point in FIG.

On the other hand, the search unit 42 fetches the second and subsequent imaging results from the frame memory 40, fetches the image of the attention area B stored in the area memory 43, and compares them. From the image A 'given as shown in b),
An operation of searching for a corresponding area B 'corresponding to the noted area B is performed. This search is performed using an appropriate pattern matching method such as a correlation method.

In the correlation method, a region B is moved on an input image A ', and a set of gray values of pixels in the input image A' at each movement position is expressed by F = (f ₁ , f ₂ , f ₃ ... f _n ) and a set R = (r ₁ , r ₂ , r ₃ ,
.. R _n ), an M value represented by the following equation is obtained, and it is determined that a corresponding area B ′ corresponding to the attention area B exists at a position where the M value is minimum.

M = (F−R) · (F−R) (1)

As described above, the search for the corresponding area B 'is performed on the display unit 5 such as a CRT display connected to the output side of the image processing unit 4 as shown in FIG.
Can be performed interactively while displaying the image shown in FIG.

Similar to the area of interest B, the corresponding area B 'thus retrieved is represented by a specific point indicating its position, for example, the coordinate value (X ₂ , Y ₂ ) of the upper left corner in the figure. , The same coordinate values (X ₁ , Y ₁ ) of the attention area B, and the imaging timings t ₁ , t _{2 of the} image A and the image A ′, together with the speed calculator 6 for calculating the descent speed of the charge 10. Is output to

As shown in FIG. 1, the charge 10 deposited in the blast furnace 1 gradually descends as the above-described reaction in the furnace inside the blast furnace 1 progresses. At this time, paying attention to the point C on the surface of the charge 10 (see FIG. 1), when the charge 10 descends to a position indicated by a broken line in the figure, the point C is set to a substantially vertical C The video camera 3 having a field of view that is inclined with respect to the vertical as described above.
, The movement appears as movement of each point in the imaging field of view in an appropriate direction, and the amount of movement corresponds to the amount of drop of the load 10.

The speed calculation unit 6 stores the coordinate values (X ₁ , X ₁ ,
Y ₁ ) and (X ₂ , Y ₂ ) are given, and using these, the speed calculation unit 6 calculates the movement amount Z in the imaging visual field by the following formula. The time required for this movement is the same as that of image A
And the imaging timings t ₁ and t ₂ of the respective images A ′,
It can be calculated by subtraction of (t ₂ −t ₁ ).
The descending speed of the charge 10 is calculated using these calculation results.

Z = {(X ₂ −X ₁ ) ² + (Y ₂ −Y ₁ ) ² } (2)

The descent speed calculated by the speed calculation unit 6 may be provided to the display unit 5 and displayed on the display unit 5, or may be provided to an output unit 7 such as a printer device and output on recording paper. May be. Furthermore, the calculated descent speed can be given to the process computer and used as information for operation management of the blast furnace 1.

In the above embodiment, the charged object 10 is obtained by comparing the results of two imagings taken at a later time.
The procedure for calculating the descent speed was described above, but the same procedure was repeated a number of times (k times), the descent speed was calculated by averaging the calculation results in each time, and the effect of pattern matching errors in each search Is desirably eliminated.

In the above embodiment, one video camera 3 is used as the imaging means. However, a plurality of video cameras can be used to perform similar imaging from a plurality of locations in the circumferential direction of the blast furnace 1. In this case, an average descent speed over the entire area inside the blast furnace 1 can be obtained with higher accuracy by averaging the descent speeds obtained from the respective imaging results as described above.

On the other hand, in FIG. 1, the imaging result is stored in a frame memory.
Although stored in the memory 40, the present invention is not limited to this, and another memory such as a RAM may be used instead of the frame memory 40.

[0052]

As described above in detail, according to the method for measuring the descending speed of the blast furnace interior charge according to the first invention, the surface of the charge deposited in the blast furnace is fixed in a fixed visual field inclined with respect to the vertical. Since the descending speed of the charged material is obtained by sequentially taking images and examining the temporal change of the imaged result, the state of falling of the charged material accumulated in the blast furnace, including the descending speed, is determined throughout the furnace. And can be used for optimizing operating conditions in addition to optimizing the charging timing of the charged material, and can contribute to the stable operation of the blast furnace.

According to the method for measuring the descending speed of the blast furnace interior charge according to the second aspect of the present invention, an attention area is extracted from one imaging result using a plurality of the imaging results obtained at a time interval, and another imaging is performed. From the result, an area corresponding to the attention area is searched,
Since the amount of movement of the region from the region of interest is determined within the fixed field of view and the speed of descent is calculated, the change over time can be accurately and efficiently examined.

According to the method for measuring the descending speed of the blast furnace interior charge according to the third invention, the one image pickup result is subjected to image processing by one or more image processing methods prepared in advance, and the image pickup result is obtained. After performing the sharpening, noise removal, contrast enhancement, and the like, the region of interest is extracted from the processed image, so that the region of interest can be accurately and efficiently extracted.

According to the descending velocity measuring device for the blast furnace interior charge according to the fourth invention, the surface of the charge deposited in the blast furnace is set in a fixed visual field having an appropriate inclination with respect to the vertical direction. Can be imaged, the imaging results are sequentially stored in a memory,
Since the stored images can be compared and the descent speed can be calculated based on the comparison result, the state of the descent of the charge deposited in the blast furnace can be accurately determined over the entire area of the furnace, including the descent speed. It can be measured and used for optimizing the operating conditions in addition to optimizing the charging timing of the charged material, and can contribute to the stable operation of the blast furnace.

According to the apparatus for measuring the descending speed of the blast furnace internal charge according to the fifth invention, the image processing is performed on one stored image stored in the memory by one or more image processing methods prepared in advance. After performing the sharpening, noise removal, contrast enhancement, and the like of the imaging result, the attention area is extracted from the processed image, so that the attention area can be accurately and efficiently extracted. The present invention has excellent effects.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the method of the present invention.

FIG. 2 is a block diagram illustrating functions of an area extracting unit.

FIG. 3 is an explanatory diagram of image processing of an area extraction unit.

FIG. 4 is an explanatory diagram of image processing of an area extraction unit.

FIG. 5 is an explanatory diagram of an operation content of an image processing unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blast furnace 2 Charging device 3 Video camera 4 Image processing part 41a Image processing means 6 Speed calculating part 10 Charged material B Attention area B 'equivalent area

Claims (5)

[Claims] 1. A method for measuring a descent speed at which a charge deposited in a blast furnace falls as a reaction in the furnace proceeds.
The surface of the charge to be deposited in the blast furnace is sequentially imaged in a fixed visual field having an appropriate inclination with respect to the vertical direction,
A method for measuring a descending speed of a blast furnace internal material, wherein the descending speed is calculated based on a temporal change of the imaging result. 2. An area of interest is extracted from one imaging result using a plurality of the imaging results obtained at a time interval, and an area corresponding to the area of interest is searched from another imaging result. 2. The method according to claim 1, wherein the amount of movement from the region of interest is determined within the fixed field of view, and the descending speed is calculated from the amount of movement and the time. 3. An image processing is performed on the one imaging result by one or more image processing methods prepared in advance.
The method according to claim 2, wherein the region of interest is extracted from the processed image on which the image processing has been performed. 4. An apparatus for measuring a descent speed of a charge deposited in a blast furnace as the reaction in the furnace proceeds,
Imaging means for imaging the surface of the charge deposited in the blast furnace in a fixed visual field having an appropriate inclination with respect to the vertical direction, a memory for sequentially storing imaging results of the imaging means, and the memory And a calculating means for calculating the descent speed based on the comparison result of the storage images. 5. The image processing apparatus according to claim 1, wherein the means for comparing the images stored in the memory includes one or more image processing means prepared in advance, and means for extracting a region of interest from the processed image processed by the image processing means. Means for searching for a region corresponding to the region of interest from another storage image, searching for a region corresponding to the region of interest from another storage image, and searching for the region of interest and the region corresponding to the region of interest. 5. The apparatus for measuring a descent speed of a blast furnace interior charge according to claim 4, wherein the values are compared.