JP2018154887A - Method and device for monitoring pulverized coal blowing condition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for monitoring pulverized coal blowing condition that can determine accurately the pulverized coal blowing condition.SOLUTION: In the blowing condition monitoring process according to one embodiment of the present invention, a large-area setting unit 77a sets a large area in the image of a raceway so as to include a tip part of a lance appearing in the captured image, and a small-area dividing unit 77b divides the large area into small areas with a rectangle having a side equal to or less than the number of pixels corresponding to a width of the tip part of the lance as a unit. A representative luminance measurement unit 77c detects the representative luminance of the small area. A blow shape detecting unit 77d detects the blowing shape of pulverized coal from the representative luminance. A diffusion degree detecting unit 77e calculates the degree of diffusion of the pulverized coal from the blowing shape of the pulverized coal. A blowing condition detecting unit 77f detects the blowing condition of the pulverized coal from the degree of diffusion.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pulverized coal blowing state monitoring method and a pulverized coal blowing state monitoring apparatus for monitoring the blowing state of pulverized coal blown into a blast furnace from a tuyere of a blast furnace.

  One of the criteria for realizing stable blast furnace operation is luminance information of the raceway section in the blast furnace observed through the tuyere of the blast furnace. The luminance information of the raceway section includes information important for the operation of the blast furnace, such as the level of furnace heat, the burning degree of pulverized coal, and the falling information of unmolten ore. The observation of luminance information through the tuyere is carried out by a sensory test performed by an operator peeking through a viewing window several times a day. In recent years, a camera is often installed in the vicinity of the tuyere, and an image (feather image) photographed by this camera is often displayed on a monitor in a monitoring room for centralized monitoring.

  A plurality of tuyere are provided in the circumferential direction of the blast furnace. It is difficult for the operator to continuously monitor the situation inside the blast furnace for all the tuyere, both in the case of direct peeking through the viewing window and in the case of centralized monitoring in the monitoring room. In view of this, a technology for monitoring the inside of the blast furnace by installing a CCD camera, a video camera, a radiation thermometer, etc. in the viewing window has been developed. From the viewing window, you can observe the state of the tip of the lance that blows in pulverized coal or city gas.

  The pulverized coal is blown into the furnace together with hot air from the tuyere to supplement coke as a reducing material charged from the top of the furnace. When the combustion of pulverized coal is delayed, the flow path of the hot air blown into the furnace is restricted, so that there is an influence on the furnace condition, for example, the furnace heat is lowered. Moreover, when blowing of pulverized coal is not performed unintentionally, a reducing material will run short and there exists an influence that an iron ore is not fully reduced.

  From such a background, Patent Document 1 discloses that when an infrared camera is installed in front of the tuyere, the temperature distribution in the tuyere is continuously recorded by image processing, and the temperature distribution in the tuyere is divided into a plurality of ranges. The data on the area ratio for each temperature and the data on the burnup of the pulverized coal are obtained, and the judgment is made by comparing with a predetermined evaluation value corresponding to the combination of the area ratio per temperature and the value of the burnup of the pulverized coal. Technology is disclosed.

  Patent Document 2 discloses a technique for detecting a blast furnace abnormality from a tuyere image taken by a camera installed in the vicinity of the blast furnace tuyere. This technology divides a tuyere image previously captured by a camera into a plurality of areas, determines the representative luminance based on the luminance value of each pixel in each area, and time-series representative luminance vectors determined by the representative luminance Collecting the representative luminance vectors from the tuyere images taken by the camera during the operation and the step of extracting the principal component vectors by performing the principal component analysis of the representative luminance vectors collected in time series A step of calculating a length of a perpendicular line from the luminance vector in the direction of the principal component vector as an evaluation value, and a step of detecting an abnormality of the blast furnace by comparing the evaluation value with a predetermined threshold value.

JP-A-5-256705 International Publication No. 2015/015936

  However, the technique disclosed in Patent Literature 1 does not divide into areas and calculate the temperature for each area, but calculates the area ratio for each temperature region. Ore omission (Patent Document 1 describes a phenomenon caused by insufficient combustion of pulverized coal, but generally refers to unmelted ore falling from the top of the raceway formed at the tuyere. ) May be found at the outer edge of the tuyere, and this phenomenon becomes a disturbance, and the burnup of pulverized coal cannot be accurately evaluated.

  Moreover, in the technique disclosed in Patent Document 2, an abnormal blowing state is determined based on the representative luminance value of the area when pulverized coal is being blown normally, but it is considered abnormal that the blowing direction has changed. Since it is only detected, it is not possible to evaluate the state of diffusion of the pulverized coal that has been blown in or the state of combustion based on this.

  An object of the present invention is to provide a pulverized coal blowing status monitoring method and a pulverized coal blowing status monitoring device capable of accurately determining the pulverized coal blowing status.

  The pulverized coal blowing status monitoring method according to the present invention is a pulverized coal blowing status monitoring method for monitoring the blowing status of pulverized coal blown into the blast furnace from the tip of the blast furnace, provided at the tuyere of the blast furnace. An imaging step of capturing an image of the raceway through the viewing window, a large area setting step of setting a large area in the image of the raceway so as to include the tip of the lance reflected in the captured image, and a tip of the tip of the lance A small area dividing step for dividing the large area into a plurality of small areas in units of a rectangle having a length equal to or less than the number of pixels corresponding to the width as a unit, and a representative luminance measuring step for detecting the representative luminance of each small area; , A blowing shape detecting step for detecting a blowing shape of pulverized coal from the representative luminance, and a diffusivity of the pulverized coal is calculated from the blowing shape of the pulverized coal. And plastid detection step, characterized in that it comprises a and a pulverized coal injection situation detecting step of detecting a blowing conditions of the pulverized coal from the degree of diffusion.

  The pulverized coal blowing state monitoring method according to the present invention, in the above invention, a luminance ratio calculation step for calculating a ratio between the maximum luminance in the captured image and the representative luminance of each small area immediately after the representative luminance measurement step, And a luminance ratio comparison step for comparing the luminance ratio for each small area.

  The pulverized coal blowing state monitoring method according to the present invention is characterized in that, in the above invention, the representative luminance is an average luminance of the small area.

  The pulverized coal blowing state monitoring method according to the present invention is characterized in that, in the above invention, the representative luminance is a maximum luminance of the small area.

  The pulverized coal blowing status monitoring device according to the present invention is a pulverized coal blowing status monitoring device that monitors the blowing status of pulverized coal blown into the blast furnace from the tip of the blast furnace, and is provided at the tuyere of the blast furnace. Imaging means for picking up an image of the raceway through the viewing window, large area setting means for setting a large area in the image of the raceway so as to include the tip of the lance reflected in the picked-up image, and the width of the tip of the lance A small area dividing unit that divides the large area into a plurality of small areas in units of a rectangle having a length equal to or less than the number of pixels corresponding to 1 and a representative luminance measuring unit that detects a representative luminance of each small area; A blowing shape detecting means for detecting a blowing shape of pulverized coal from the representative luminance; a diffusivity detecting means for calculating a diffusivity of the pulverized coal from the blowing shape of the pulverized coal; Characterized in that it and a pulverized coal injection situation detection means for detecting a blowing conditions of the pulverized coal from the tides.

  According to the pulverized coal blowing status monitoring method and the pulverized coal blowing status monitoring device according to the present invention, the pulverized coal blowing status is determined from the pulverized coal blowing shape reflected in the actual image. Can be judged well.

FIG. 1 is a schematic diagram showing a schematic configuration of a blast furnace to which a pulverized coal blowing state monitoring apparatus according to an embodiment of the present invention is applied. FIG. 2 is a schematic diagram showing a configuration of a pulverized coal blowing state monitoring apparatus according to an embodiment of the present invention. FIG. 3 is a flowchart showing a flow of pulverized coal blowing state monitoring processing according to an embodiment of the present invention. FIG. 4 is a conceptual diagram of a captured image captured by the tuyere camera. FIG. 5 is a conceptual diagram for explaining a small area dividing method. FIG. 6 is a schematic diagram showing a pattern of pulverized coal blowing shape. FIG. 7 is a schematic diagram showing the luminance distribution for each column of the small area.

  Hereinafter, the configuration and operation of a pulverized coal blowing state monitoring apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

[Configuration of blast furnace]
First, with reference to FIG. 1, the structure of the blast furnace to which the pulverized coal blowing condition monitoring apparatus which is one embodiment of this invention is applied is demonstrated.

  FIG. 1 is a schematic diagram showing a schematic configuration of a blast furnace 1 to which a pulverized coal blowing state monitoring apparatus 10 (see FIG. 2) according to an embodiment of the present invention is applied. As shown in FIG. 1, a blast furnace 1 is charged with iron ore 21 and coke 23 from the top of the furnace, separates pig iron (hot metal) 25 obtained at the bottom of the furnace from slag 27 and discharges it outside the furnace. Then, hot air is blown from the tuyere 11 provided in the lower part of the furnace, and the iron ore 21 is reduced and melted using the coke 23 as a heat source to obtain molten iron 25. Since the specific gravity is smaller than the hot metal 25, the slag 27 is separated into the upper layer of the hot metal 25.

  In the blast furnace 1, one end of a blower pipe 13 for blowing hot air is connected to the tuyere 11. A lance 15 is installed in the middle of the blast pipe 13 through the blast pipe 13, and pulverized coal is introduced into the hot air by the lance 15 (arrow Y11). Hot air (arrow Y13) blown through the blow pipe 13 is introduced into the blast furnace 1 from the tuyere 11 together with pulverized coal, and burns mainly in a combustion space called a raceway 17 ahead of the tuyere 11 in the hot air blowing direction. Contribute to.

  A tuyere observation unit 3 is installed on the other end side of the blower tube 13 facing the tuyere 11. This tuyere observation unit 3 is a tuyere for photographing the state of the blast furnace 1 in operation, specifically, the state inside the blower tube 13 and the state inside the blast furnace 1 (furnace state) via the tuyere 11. A camera (camera) 31, a viewing window 33 for visually observing the state of the blast furnace 1, and a half for branching the optical path shown by the alternate long and short dash line in FIG. 1 to the tuyere camera 31 side and the viewing window 33 side The mirror 35 is installed and unitized.

  Here, a plurality of tuyere 11 are arranged in the circumferential direction of the blast furnace 1, and the tuyere observation unit 3 is provided on the other end side of the blower tube 13 having one end connected to the plurality of tuyere 11. The tuyere cameras 31 are installed in whole or in part, and each pulverized coal blowing state monitoring device 10 is configured.

[Configuration of pulverized coal injection status monitoring device]
Next, with reference to FIG. 2, the structure of the pulverized-coal blowing condition monitoring apparatus which is one Embodiment of this invention is demonstrated.

  FIG. 2 is a schematic diagram showing the configuration of the pulverized coal blowing state monitoring apparatus according to an embodiment of the present invention, and the tuyere 11 arranged in the circumferential direction of the blast furnace 1 and the tuyere observation unit 3 are installed. The positional relationship with the tuyere camera 31 is also shown. As shown in FIG. 2, in this embodiment, tuyere cameras 31 (31-1 to 31-8) are installed in eight tuyere 11 selected at substantially equal intervals along the circumferential direction of the blast furnace 1. Yes. Each tuyere camera 31 outputs image data of tuyere images obtained by photographing the situation of the blast furnace 1 to the image acquisition device 5 as needed. The tuyere cameras 31 need only be installed in at least a plurality of tuyere 11, and the tuyere 11 to be installed and the number thereof may be set as appropriate.

  As described above, the pulverized coal blowing state monitoring apparatus 10 according to an embodiment of the present invention includes a plurality of tuyere cameras 31 installed in a plurality of (e.g., eight) tuyere 11, the image acquisition apparatus 5, and an image. And a processing device 7. The image acquisition device 5 and the image processing device 7 are realized using a general-purpose computer such as a workstation or a personal computer.

  The image acquisition device 5 captures image data of tuyere images (moving images) continuously photographed by the tuyere cameras 31 during operation of the blast furnace 1 and transfers them to the image processing device 7 as needed.

  The image processing apparatus 7 includes an input unit 71, a display unit 73, a recording unit 75, and a processing unit 77 as main functional units.

  The input unit 71 is for inputting information necessary for detecting an abnormality of the blast furnace 1 and outputs an input signal corresponding to the operation input to the processing unit 77. The input unit 71 is realized by an input device such as a keyboard, a mouse, a touch panel, and various switches. The display unit 73 is for performing monitor display of tuyere images taken by each tuyere camera 31, for example, abnormality notification of the blast furnace 1, and the like, and various types based on display signals input from the processing unit 77. Display the screen. The display unit 73 is realized by a display device such as an LCD, an EL display, or a CRT display.

  The recording unit 75 is realized by an update recordable flash memory, a built-in or data recording terminal connected hard disk, an information recording medium such as a memory card, and a read / write device thereof, and appropriately adopts a recording device according to the application. Can be used. In the recording unit 75, a program for operating the image processing device 7 and realizing various functions provided in the image processing device 7, data used during the execution of the program, and the like are recorded in advance. Alternatively, it is temporarily recorded for each processing.

  The processing unit 77 is realized by a CPU or the like, and based on an input signal input from the input unit 71, a program or data recorded in the recording unit 75, instructions to each unit constituting the image processing apparatus 7 and data The operation of the image processing apparatus 7 is controlled by performing transfer or the like. The processing unit 77 includes a large area setting unit 77a, a small area dividing unit 77b, a representative luminance measuring unit 77c, a blowing shape detecting unit 77d, a diffusivity detecting unit 77e, and a blowing state detecting unit 77f. Process to monitor the pulverized coal blowing status.

  The pulverized coal blowing state monitoring apparatus 10 having such a configuration accurately determines the pulverized coal blowing state by executing the following blowing state monitoring process. Hereinafter, with reference to FIG. 3, the operation of the pulverized coal blowing state monitoring apparatus 10 when performing the blowing state monitoring process will be described.

[Blowing status monitoring process]
FIG. 3 is a flowchart showing the flow of the blowing status monitoring process according to the embodiment of the present invention. The flowchart shown in FIG. 3 starts at the timing when the execution instruction of the blowing state monitoring process is input to the image processing apparatus 7 via the input unit 71, and the blowing state monitoring process proceeds to the process of step S1.

  In the processing of step S1, each tuyere camera 31 takes an image of the raceway 17 through the viewing window 11, and the image acquisition device 5 takes the image of the raceway 17 taken by each tuyere camera 31 as an image processing device. Forward to 7. FIG. 4 is a conceptual diagram of a captured image captured by the tuyere camera 31. As shown in FIG. 4, when capturing an image of the raceway 17, the position of each tuyere camera 31 is adjusted so that the tip of the lance 15 is reflected at the center of the intra-feather image G. Further, since the temperature of the lance 15 is lower than that of the raceway 17, when the exposure of each tuyere camera 31 is adjusted so that the state of the raceway 17 is reflected, the lance 15 appears black like a shadow. The same applies to pulverized coal blown from the lance 15. Further, depending on the number of the lances 15, there are cases where the lance 15 is laid from the right to the left of the field of view of the tuyere camera 31, or may be projected obliquely from above the field of view of the tuyere camera 31. In the present embodiment, a case where the lance 15 is laid from the right to the left of the field of view of the tuyere camera 31 will be described. Thereby, the process of step S1 is completed and the blowing state monitoring process proceeds to the process of step S2.

  In the process of step S2, the large area setting unit 77a sets a large area in the image of the raceway 17 so as to include the tip of the lance 15 shown in the tuyere image G. Specifically, as described above, the outline of the tip of the lance 15 can be clearly confirmed by comparison with the raceway 17. Accordingly, the large area setting unit 77 a sets a rectangular large area in the image of the raceway 17 so as to include the tip of the lance 15. At this time, it is desirable to confirm in advance to what extent the pulverized coal is diffused in advance, and to make the size of the large area sufficiently large to cover the diffusion region of the pulverized coal. Thereby, the process of step S2 is completed, and the blowing state monitoring process proceeds to the process of step S3.

  In the process of step S3, the small area dividing unit 77b uses a square whose length is equal to or less than the number of pixels corresponding to the width of the tip of the lance 15 as a unit, and converts the large area set by the process of step S2 into a plurality of areas. Divide into smaller areas. Specifically, as shown in FIG. 5, the small area dividing unit 77 b sets a quadrangle that is in contact with the center of the tip of the lance 15 as the small area A <b> 2. Hereinafter, this small area A2 is referred to as a reference small area A2. Then, the small area dividing unit 77b divides the large area A1 into a plurality of small areas on the basis of the quadrangle set in the reference small area A2. When the large area A1 is divided into small areas, if a surplus portion occurs at the outer edge of the large area, the large area A1 is divided according to the size of the small area. At this time, one side of the small area is preferably set smaller than the number of pixels corresponding to the diameter of the tip of the lance 15 and smaller than ½ of the number of pixels corresponding to the diameter of the tip of the lance 15. This is to make an image of pulverized coal appear in a small area even when the flow of pulverized coal to be blown is thin. Thereby, the process of step S3 is completed and the blowing state monitoring process proceeds to the process of step S4.

  In the process of step S4, the representative luminance measuring unit 77c detects the representative luminance of each small area. Specifically, the representative luminance measuring unit 77c calculates the average luminance or the maximum luminance of each small area as the representative luminance of each small area. Thereby, the process of step S4 is completed, and the blowing state monitoring process proceeds to the process of step S5.

  In the process of step S5, the blowing shape detection unit 77d detects the blowing shape of pulverized coal from the representative luminance of each small area calculated by the process of step S4. Specifically, the inventors of the present invention have found that the pulverized coal blowing shape is roughly divided into four patterns shown in FIGS. That is, in the pulverized coal blowing shape shown in FIG. 6 (a), there is no image of pulverized coal, and in the pulverized coal blowing shape shown in FIG. 6 (b), the pulverized coal C does not diffuse and falls. Further, in the pulverized coal blowing shape shown in FIG. 6C, the pulverized coal C is diffused and blown, but the outline of the outer edge of the pulverized coal C is clear, and the pulverized coal C shown in FIG. In the blown shape, the pulverized coal C is diffused and blown, but the outer edge of the pulverized coal C is unclear.

  In the pulverized coal blowing shape shown in FIG. 6A, there is a possibility that clogging occurs somewhere in the blower pipe 13. In addition, in the pulverized coal blowing shape shown in FIG. 6 (b), although the pulverized coal is blown, the pulverized coal is not sufficiently exposed to oxygen because the diffusibility of the pulverized coal is not sufficient. It may not progress. Further, in the pulverized coal blowing shape shown in FIG. 6C, there is a possibility that the pulverized coal is not sufficiently in contact with oxygen due to deformation of the blow pipe 13 or the like. In addition, the pulverized coal blowing shape shown in FIG. 6 (d) shows a situation where the diffusibility of the pulverized coal is good and the outer edge of the pulverized coal is in contact with oxygen and burns well.

  At this time, the luminance of the small area is considered to change as follows. That is, in the pulverized coal blowing shape shown in FIG. 6A, there is no difference in representative luminance between small areas. In the pulverized coal blowing shape shown in FIG. 6 (b), the pulverized coal descends as it is, so when comparing the representative luminance in the vertical direction of the small area, the left column shows higher luminance and the change for each small area is In addition, the brightness above the tip of the lance 15 is high in a small area near the tip of the lance 15, but the brightness is greatly reduced in the small area below the tip of the lance 15.

  In the pulverized coal blowing shape shown in FIG. 6 (c), the pulverized coal diffuses in a fan shape, so the low luminance range is wide in the small area row near the left end, and when the lance 15 is approached, the low luminance range is It gets narrower. Also, the change in luminance in the direction from top to bottom is abrupt. In the pulverized coal blowing shape shown in FIG. 6 (d), the luminance distribution in the left-right direction has a low luminance range in the small area column near the left end as in the pulverized coal blowing shape shown in FIG. 6 (c). As the width approaches the right side close to the tip of the lance 15, the low luminance range becomes narrower. Further, in FIG. 6D, the density change is gentle because the density near the tip of the pulverized coal flow is low and the brightness is relatively high even at a location near the center of the flow. FIG. 7 is a schematic diagram showing the luminance distribution for each column of the small area. Each graph in FIGS. 7B to 7E shows a change in luminance for each column created by extracting representative luminances of small areas arranged in the vertical direction in FIG. 7A.

  Therefore, the blowing shape detection unit 77d calculates the average value of the representative brightness using the maximum value and the minimum value of the representative brightness of the small area, and the representative brightness is calculated using the average value of the representative brightness as a threshold for the focused small area. When it is lower than the threshold value, pulverized coal is present in the small area, and when the representative luminance is higher than the threshold value, it is determined that there is no pulverized coal in the small area. Note that the brightness of the entire image in the tuyere increases and decreases as the furnace heat increases and decreases. At this time, the ratio between the maximum luminance of the whole tuyere image and the representative luminance of each small area is calculated. And the diffusion area | region of pulverized coal is set not by the threshold value of a brightness | luminance but by comparison of a brightness ratio. In particular, when the luminance of the entire image in the tuyere changes, it is preferable to compare and judge by the luminance ratio with the maximum luminance. In this way, it is possible to accurately compare and evaluate the pulverized coal blowing shape even if the overall luminance changes without being influenced by temporal luminance fluctuations. Thereby, the process of step S5 is completed, and the blowing state monitoring process proceeds to the process of step S6.

  In the process of step S6, the diffusivity detector 77e calculates the diffusivity of the pulverized coal from the pulverized coal blowing shape detected by the process of step S5. Specifically, the pulverized coal blowing state in the actual operation is the intermediate state between the state shown in FIG. 6 (b) and FIG. 6 (c), or the state shown in FIG. 6 (c) and FIG. 6 (d). It is thought that there may be some cases. For this reason, it is desirable to index the diffusion degree of pulverized coal and determine the blowing state. Hereinafter, a method for calculating the diffusivity will be described. Assuming that a plurality of small areas are composed of m rows and n columns, the reference small area A2 may be arranged at a coordinate position of (m / 2, n). It is also desirable to cover an area where pulverized coal falls as wide as possible. Here, among the small areas farthest from the tip of the lance 15, the upper left small area is (1, 1), and a number is assigned to each small area. In this case, the lower right small area is (m, n). Further, the i-th small area in the row direction and the j-th small area in the column direction are numbered (i, j).

  Next, the average of the representative luminance for each column is obtained. At this time, as a result of the examination of the situation shown in FIGS. 6 (a) to 6 (d), the pulverized coal falls, so that i> m / 3 is small. Pay attention to the representative luminance of the area. However, a small area where the inner wall of the tuyere 11 is reflected at this time is excluded from the calculation in advance. The average luminance of a small area where i> m / 3 in the j-th column is A (j) (j = 1, 2, 3,..., N). The average luminance A (1) is examined in order from the average luminance A (n), and the number of rows that fall below a preset threshold is counted. The total value counted at this time is defined as the diffusivity. Thereby, the process of step S6 is completed, and the blowing state monitoring process proceeds to the process of step S7.

  In the process of step S7, the blowing state detection part 77f detects the blowing state of pulverized coal from the diffusivity calculated by the process of step S6. Specifically, the blowing state detection unit 77f determines that the smaller the diffusivity, the more the pulverized coal does not diffuse and the lower the combustibility. In addition, the blowing state detection unit 77f compares the diffusivities of the plurality of tuyere 11 and determines that the blower tube 13 is clogged when the diffusivity is significantly reduced only in a certain tuyere 11. Thereby, the process of step S7 is completed and a series of blowing condition monitoring processes are completed.

  As is clear from the above description, in the blowing state monitoring process according to the embodiment of the present invention, the large area setting unit 77a includes the tip of the lance 15 shown in the captured image so that the inside of the image of the raceway 17 is included. The small area dividing unit 77b divides the large area into small areas with a square having a length equal to or less than the number of pixels corresponding to the width of the tip of the lance 15 as a unit, and measures representative luminance. The unit 77c detects the representative luminance of the small area, the blowing shape detection unit 77d detects the blowing shape of the pulverized coal from the representative luminance, and the diffusivity detecting unit 77e detects the diffusivity of the pulverized coal from the blowing shape of the pulverized coal. And the blowing state detection unit 77f detects the blowing state of pulverized coal from the diffusivity. Thereby, since the blowing state of pulverized coal is determined from the blowing shape of pulverized coal reflected in the actual image, the blowing state of pulverized coal can be accurately determined.

  As mentioned above, although the embodiment to which the invention made by the present inventors was applied has been described, the present invention is not limited by the description and the drawings that constitute a part of the disclosure of the present invention according to this embodiment. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Blast furnace 5 Image acquisition apparatus 7 Image processing apparatus 10 Pulverized coal blowing condition monitoring apparatus 11 Tuyere 13 Blower pipe 15 Lance 17 Raceway 31 Tuyere camera 71 Input part 73 Display part 75 Recording part 77 Processing part 77a Large area setting part 77b Small area division unit 77c Representative luminance measurement unit 77d Blow shape detection unit 77e Diffusion degree detection unit 77f Blow state detection unit

Claims (5)

A pulverized coal blowing status monitoring method for monitoring the blowing status of pulverized coal blown into the blast furnace from the blast furnace tip,
An imaging step of capturing an image of the raceway through a viewing window provided at the tuyere of the blast furnace;
A large area setting step for setting a large area in the image of the raceway so as to include the tip of the lance reflected in the captured image;
A small area dividing step of dividing the large area into a plurality of small areas in units of a rectangle having a length equal to or less than the number of pixels corresponding to the width of the tip of the lance;
A representative luminance measurement step for detecting the representative luminance of each small area;
A blowing shape detection step of detecting the blowing shape of pulverized coal from the representative luminance;
A diffusivity detection step of calculating a diffusivity of the pulverized coal from the blowing shape of the pulverized coal;
A pulverized coal blowing state detection step for detecting the blowing state of the pulverized coal from the diffusivity;
A pulverized coal blowing state monitoring method characterized by comprising:   Immediately after the representative luminance measuring step, a luminance ratio calculating step for calculating a ratio between the maximum luminance in the captured image and the representative luminance of each small area, and a luminance ratio comparing step for comparing the luminance ratio for each small area, The pulverized coal blowing state monitoring method according to claim 1, wherein:   The pulverized coal blowing state monitoring method according to claim 1 or 2, wherein the representative luminance is an average luminance of the small area.   The pulverized coal blowing state monitoring method according to claim 1 or 2, wherein the representative luminance is a maximum luminance of the small area. A pulverized coal blowing status monitoring device for monitoring the blowing status of pulverized coal blown into the blast furnace from the blast furnace tip,
Imaging means for capturing an image of the raceway through a viewing window provided at the tuyere of the blast furnace;
A large area setting means for setting a large area in the image of the raceway so as to include the tip of the lance reflected in the captured image;
Small area dividing means for dividing the large area into a plurality of small areas in units of a quadrangle whose side is a length equal to or less than the number of pixels corresponding to the width of the tip of the lance;
Representative luminance measuring means for detecting the representative luminance of each small area;
Blowing shape detection means for detecting the blowing shape of pulverized coal from the representative luminance;
A diffusivity detecting means for calculating a diffusivity of the pulverized coal from the blowing shape of the pulverized coal;
Pulverized coal blowing status detection means for detecting the pulverized coal blowing status from the degree of diffusion;
A pulverized coal blowing state monitoring device comprising: