JP2017150035A - Display method for blast furnace profile meter, and method for charging material to be charged in blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct a deposition profile in a new charging operation to optimize the operation of a blast furnace by displaying the descending speed or descending amount of a charging material.SOLUTION: A display method for blast furnace profile meter includes: measuring the deposition profiles immediately before and after charging in every charging operation; comparing the deposition profile just after charging at the previous charging with that just before charging at this time charging; calculating a descending speed or a descending amount at each position on the surface of the charging material in the period from just after previous charging to just before this time charging; and displaying a surface image showing distribution of the descending speed or descending amount on the surface of the charging material, and a sectional image showing the descending speed or amount at an optional position of the surface of the charging material.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a display method of a blast furnace profile meter that detects the accumulation state of iron ore and coke charged in a blast furnace. In addition, the present invention relates to a method for charging a blast furnace with a charge reflecting the display method.

  In a blast furnace that melts iron ore, iron ore and coke are normally charged from the top of the furnace with a large bell (bell-type charging device) or a shooter (bell-less charging device) and deposited in layers. doing.

  One of the important factors for stable operation of the blast furnace is the distribution of gas flow in the furnace. This gas flow distribution is closely related to the iron ore and coke deposits, and usually the deposition state where the gas flow distribution is optimal by experiment, that is, the angle of the slope of the deposit, the iron ore Obtain the theoretical deposition profile that optimizes the layer thickness ratio between the deposition layer and the coke deposition layer, and control the operation of the large bell and shooter so that the actual deposition condition matches the theoretical deposition profile. The amount of stone and coke dropped is adjusted.

  In order to check whether the deposits are consistent with the theoretical deposition profile, microwaves and millimeter waves are transmitted to the iron ore or coke deposition surface immediately after charging and reflected on the iron ore or coke surface. A deposition profile is obtained by receiving reflected waves.

  As a detection device (profile meter) for detecting this deposition profile, for example, in Patent Document 1, as shown in FIG. The microwave from the transmission / reception means 3 is transmitted toward the charge 7 (iron ore 7a or coke 7b) in the furnace, and the microwave reflected by the surface of the charge 7 is received by the antenna 2 to receive the microwave. Detection is performed by the transmission / reception means 3, and the distance to the surface of the charge 7 is obtained from the time difference between transmission and reception. At this time, the deposition profile of the charge 7 is obtained by reciprocating the lance 1 from the furnace wall 5 toward the axis 4 of the blast furnace 6. As shown in the figure, the accumulation state of the charge 7 is in the shape of a reverse bell that is deepest on the axis 4 of the blast furnace 6 and gradually becomes shallower toward the furnace wall 5. By measuring the distance to 7, the deposition profile of the charge 7 can be detected linearly (two-dimensionally).

  In addition, as shown in FIG. 2, the applicant of the present application previously provided a reflector 120 immediately above the opening 6 a provided near the top of the blast furnace 6 and opposed to the reflector 120. The antenna 111 is arranged, the detection wave M from the microwave transmitting / receiving means 110 is transmitted from the antenna 111, reflected by the reflector 120, and sent into the furnace, and the charge 7 (iron ore 7a and coke in the furnace) is sent. The reflected wave reflected in 7b) is reflected by the reflecting plate 120 and sent to the microwave transmitting / receiving means 110, and the reflecting surface is rotated in two directions orthogonal to each other by an angle variable mechanism (not shown) attached to the reflecting plate 120. Proposed is a profile meter 100 that three-dimensionally detects a deposition profile by moving the surface of the charge 7 in a plane by moving the transmitted wave.

  In the profile meters as described in Patent Documents 1 and 2, position information (deposition amount at the position of the charge) based on the measured deposition profile is used as a large bell (Fig. 1 and the shooter (reference numeral 10 in FIG. 2) to control the amount of iron ore and coke dropped from the large bell, the rotation speed of the shooter, and the like.

JP-A-7-34107 Japanese Patent No. 5391458

  By the way, with the operation of the blast furnace, the surface level of the charge gradually decreases, but the lowering speed becomes faster on the furnace wall side than the central part of the blast furnace. Since a core is formed at the center of the blast furnace, the amount of descent increases around the center so as to avoid the center. Such a phenomenon that the descent speed increases on the furnace wall side is likely to occur in a large blast furnace.

  Further, since iron ore and coke are agglomerates of various sizes, they often do not fall uniformly in a planar shape, and there are locally a portion where the descent rate is slow and a portion where the descent rate is fast.

  Such partial differences in the descent speed and descent amount cannot be determined by just looking at the deposition profile immediately after charging. Actually, it is assumed that the descent speed is uniform, and the charging amount is set so that the theoretical deposition profile is obtained at the time of new charging based on the deposition profile immediately after the previous charging. It does not reflect the actual descent speed or amount of descent between this charging operation and the current charging operation.

  If a new charging operation is performed while leaving a part where the descent speed and descent amount are significantly different from other parts, that is, a part where the descent speed and descent amount are abnormal, the optimum operation according to the theoretical deposition profile is performed. I can't.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to display a charging rate or amount of charging to correct a deposition profile in a new charging operation so that the operation of a blast furnace can be optimized.

In order to solve the above problems, the present invention provides the following blast furnace profile meter display method and blast furnace charging method.
(1) A detection wave is transmitted to the surface of the charge that has been charged and deposited in the blast furnace, and a reflected wave reflected by the surface of the charge is received to deposit at each position on the surface of the charge. A method of displaying a blast furnace profile meter for detecting a deposition profile indicating a quantity,
Compare the deposition profile immediately after charging at the previous charging with the deposition profile immediately before charging at the current charging, and the amount of charge in the period from immediately after the previous charging to just before the current charging. Calculate the descent speed or descent amount at each position on the surface,
A blast furnace profile meter characterized by displaying a surface image showing a descending speed or amount distribution on the surface of the charge and a cross-sectional image showing a descending speed or amount at any position on the surface of the charge How to display.
(2) In the surface image, the surface of the charge is divided into a plurality along the diameter, and a line segment corresponding to the divided diameter is displayed.
In the cross-sectional image, the cross-sectional image along the line segment is displayed.
(3) When an abnormality is found in the descending speed or the descending amount, an abnormal part is extracted, and an image in a predetermined number of times of charging work before the previous charging work is displayed (1) ) Or the display method of the blast furnace profile meter according to (2).
(4) The image is monitored based on the display method described in any one of (1) to (3) above, and the charging means is controlled when charging the blast furnace. The charging method of the charge to the blast furnace characterized.

  According to the present invention, by detecting and displaying the actual descending speed or descending amount of the charged material, it is possible to optimally operate the blast furnace by correcting the deposition profile in a new charging operation.

It is a figure which shows an example (two-dimensional deposition profile measurement) of a profile meter. It is a figure which shows the other example (three-dimensional deposition profile measurement) of a profile meter. It is the (A) surface image and (B) cross-sectional image which show the accumulation profile of the charge immediately after the insertion at the time of the last charge. It is the (A) surface image and (B) cross-sectional image which show the accumulation profile of the charging material just before charging at the time of this charging. It is (A) surface image and (B) cross-sectional image which show descent speed or descent amount. It is a figure which shows the other example of a display of (A) surface image and (B) cross-sectional image. It is a figure which shows the example of a display when there are two or more descent | fall abnormal parts.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  In the present invention, as a method for detecting the charge accumulation profile, the surface of the charge 7 is scanned in a planar manner by rotating the reflector 120 as shown in FIG. A method of measuring the deposition profile is preferred. With this three-dimensional deposition profile, the amount of deposition at each position on the surface of the charge 7 can be accurately measured, and a cross section at any position on the surface of the charge 7 can be obtained.

In the present invention, the deposition profile is measured immediately before and immediately after the charging operation.
Then, by comparing the deposition profile immediately after charging at the previous charging with the deposition profile immediately before charging at the current charging, charging between the previous charging and the current charging is performed. You can know the descending state of an object.

  FIG. 3 is an example of a deposition profile immediately after charging at the time of the previous charging. FIG. 3A is a surface image showing a deposition state of the surface of the charging material, and FIG. 3B is a charging image. It is a cross-sectional image which shows the deposition amount (deposition height) along the arbitrary straight lines of the surface of an object. Further, in FIG. 3A, the accumulation state on the surface of the charge is indicated by contour lines connecting the points of the same accumulation amount.

  FIG. 4 is an example of a deposition profile immediately before charging at the time of the current charging. FIG. 4A is a surface image, and FIG. 4B is a cross-sectional image. 4A shows that the portion indicated by the symbol H (H portion) is greatly depressed, and FIG. 4B shows the diameter passing through the vicinity of the center of the H portion (of FIG. 4A). The amount of deposition along the horizontal line is displayed.

  Therefore, by comparing the image of FIG. 3 and the image of FIG. 4, it can be seen that the descending speed or amount of the charge in the H portion is larger than that in the other portions. Note that the image of FIG. 4B (two-dot chain line in the drawing) can also be superimposed on FIG. 3B.

  FIGS. 5A and 5B are images showing the descending speed or the amount of descending obtained from FIGS. 3 and 4. FIG. 5A is a surface image, and FIG. 5B is a cross-sectional image. In the portion other than the H portion, the descending speed or the amount of descent is substantially constant and the variation allowable range A, whereas the H portion includes a portion exceeding the allowable variation range A (shaded portion in the figure). . The fluctuation allowable range A can be arbitrarily set.

  In this way, by comparing the deposition profile immediately after the previous charging with the deposition profile immediately before the current charging, the descending speed or amount of the charged material from the previous charging to the current charging is reduced. , And a portion where the descent speed or amount of descent is significantly different from other portions (descent abnormal portion) such as the H portion can be known. In consideration of this descent abnormal portion, it is useful for controlling the large bell (symbol 8 in FIG. 1) and the shooter (symbol 10 in FIG. 2) as the charging means during the current charging operation. Operation can be performed more stably. Specifically, the distribution of the charging amount from the charging means and the coke ratio are adjusted based on the descending speed or the descending amount. It is also possible to adjust the amount of hot air supplied from the tuyere, the air temperature, the humidity, the amount of PCI (pulverized coal), and the like so as not to cause an abnormal descent. Alternatively, an alarm may be issued when there is an abnormal part of descent.

  The display format of the image can be variously changed. For example, FIG. 6 is a cross-sectional image (B) showing the descent speed or descent amount in the surface image (A) and line segments (X1, X2, X3, X4) corresponding to FIG. In the surface image, an arbitrary position on the surface, for example, a horizontal line (a line connecting a position of X = 0 ° and a position of X = 180 °) in the figure is X1, a line X2 orthogonal to X1 (a position of X = 90 °) And a line connecting the line X1 and the line X2 into two equal parts on both sides of the line X2 (a line connecting the position of X = 45 ° and the position of X = 225 °) ) And the line X4 (line connecting the position of X = 135 ° and the position of X = 315 °) are displayed in an overlapping manner. At the same time, in the cross-sectional image of FIG. 5B, the cross-sections along the lines X1 to X4 are displayed in an overlapping manner with different line types and line colors (in the example of the figure, four line types are changed).

  In addition, the space | interval of line X1-X4, ie, an angle difference, can be arbitrarily set other than 45 degrees mentioned above. Further, the display locations are not limited to the four locations of the lines X1 to X4, and can be increased or decreased. Further, FIG. 4A shows a surface image when the line X1 is at a position of X = 0 °, but the line X1 is directed to the line X3 side (upward) or the line X4 side (downward) at an arbitrary angle. A rotated surface image can also be displayed.

  There may also be multiple descent abnormalities. For example, as shown in FIG. 7, in the case where there are two descending abnormal portions, the H10 portion and the H20 portion, line segments X10 and X20 passing near the centers of the H10 portion and the H20 portion in the surface image of FIG. Is displayed, and line segments X10 and X20 corresponding to the diameters passing through the respective centers are displayed, and the cross-sections along the lines X10 and X20 are superimposed on the cross-sectional image of FIG.

  Furthermore, measurement data of descent speed or descent amount can be recorded continuously, displayed at any number of times to determine the change in descent speed or descent amount, and reflected in blast furnace control such as charging method. it can.

DESCRIPTION OF SYMBOLS 1 Lance 2 Antenna 3 Microwave transmission / reception means 6 Blast furnace 7 Charge 7a Iron ore 7b Coke 8 Large bell 10 Shuta 110 Microwave transmission / reception means 111 Antenna 120 Reflector

Claims (4)

The detection wave is transmitted to the surface of the charge that is charged and deposited in the blast furnace, and the reflected wave reflected by the surface of the charge is received to indicate the amount of deposition at each position on the surface of the charge. A method for displaying a blast furnace profile meter for detecting a deposition profile,
Compare the deposition profile immediately after charging at the previous charging with the deposition profile immediately before charging at the current charging, and the amount of charge in the period from immediately after the previous charging to just before the current charging. Calculate the descent speed or descent amount at each position on the surface,
A blast furnace profile meter characterized by displaying a surface image showing a descending speed or amount distribution on the surface of the charge and a cross-sectional image showing a descending speed or amount at any position on the surface of the charge How to display. In the surface image, the surface of the charge is divided into a plurality along the diameter, and a line segment corresponding to the divided diameter is displayed.
The blast furnace profile meter display method according to claim 1, wherein a cross-sectional image along the line segment is displayed in the cross-sectional image.   3. The method according to claim 1, wherein when an abnormality is observed in the descending speed or the descending amount, an abnormal part is extracted and an image in a predetermined number of times of charging work before the previous charging work is displayed. To display the blast furnace profile meter. An image is monitored based on the display method according to any one of claims 1 to 3, and the charging means is controlled when charging the charging material into the blast furnace. How to charge the charge.

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