JP2023057594A - Blast furnace operation method, charging method control device, and charging method control program - Google Patents

Abstract

To realize the stable operation of a blast furnace by managing tilt angles of an ore terrace.SOLUTION: In a blast furnace operation method of mutually forming an ore layer and a coke layer in a furnace to tilt the deposition shape at a furnace top downward toward a furnace center side, ore terrace tilt angles of the ore layer formed in the furnace are acquired for each in plural furnace diameter directions, and a representative value determined based on the acquired plural ore terrace tilt angles is used as an operation control index to execute an operation so that the representative value satisfies a standard range.SELECTED DRAWING: Figure 2

Description

The present invention relates to a blast furnace operating method, a charging method control device, and a charging method control program.

A blast furnace is charged with alternating layers of ore layer charging raw material for forming an ore layer (hereinafter referred to as ore raw material) and coke layer charging raw material for forming a coke layer (hereinafter referred to as coke raw material). is entered. The pile shape of the blast furnace charge has a great influence on the operation of the blast furnace. Since the charged ore raw material is melted in the lower part of the blast furnace, the reducing gas introduced from the tuyere rises through the coke layer in the furnace. In order to operate a blast furnace stably, it is preferable to distribute the gas uniformly in the furnace, and it is desired to form a coke layer that can achieve this.

In a method of operating a blast furnace in which the deposition shape at the furnace top is inclined downward toward the center of the furnace, ore terraces smaller than the angle of repose of the ore are formed in the ore layer near the furnace wall. Patent Document 1 discloses that the ore terrace inclination angle is kept within the range of ±15 degrees, and the relative distance obtained by dividing the distance from the top of the terrace of the burden layer near the furnace top to the furnace wall by the furnace diameter is set to 0.5 degrees. A method of forming an ore terrace is disclosed that controls the swirl chute to be in the range of 1-0.6.

JP-A-11-92808

As described above, in Patent Document 1, an ore terrace that slopes downward toward the furnace wall side (an ore terrace having a negative ore terrace inclination angle, hereinafter also referred to as a "minus ore terrace") is provided. allow to form. In a blast furnace operation method in which a negative ore terrace is formed, the thickness of the coke layer in the furnace radial direction or the furnace circumferential direction is inconsistent unless the shoulder of the ore terrace and the shoulder of the coke terrace are aligned in the radial direction. The flow becomes uniform, and the flow of the reducing gas becomes uneven. However, due to the particle size distribution of the ore raw material, wear of the charging chute, and the like, the shoulder of the ore terrace may be formed at a deviation from the intended position. In this case, even if the coke can be charged at the intended position, the thickness of the coke layer stacked on the ore layer in the furnace radial direction or the furnace circumferential direction becomes uneven, or the flow of the reducing gas is uneven. Stable operation of the blast furnace is hindered.

An object of the present invention is to realize stable operation of a blast furnace by appropriately managing the inclination angle of the ore terrace and suppressing variations in the thickness of the coke layer laminated on the ore layer.

In order to solve the above problems, the method for operating a blast furnace according to the present invention includes: (1) alternately forming an ore layer and a coke layer in the furnace, and directing the deposition shape at the furnace top downward toward the center of the furnace; In the blast furnace operating method in which the ore layer formed in the furnace is inclined to a plurality of ore terrace inclination angles in each of a plurality of furnace radial directions, a representative value determined based on the acquired plurality of ore terrace inclination angles as an operation control index, and a method of operating a blast furnace in which the representative value satisfies the reference range.

(2) The method of operating a blast furnace according to (1), wherein the representative value is the minimum value of the plurality of ore terrace inclination angles obtained.

(3) The method of operating a blast furnace according to (2), wherein the reference range is 0° or more.

(4) The method of operating a blast furnace according to (2), wherein the reference range is 5° or more.

(5) The total number of notches of the revolving chute provided in the blast furnace is n, the notch number is k, the tilt angle of the revolving chute at notch number k is θk, the number of revolutions of the revolving chute at notch number k is Sk, and the revolving chute is Assuming that the total number of turns is T, relationship information that is the relationship between the first angle calculated based on formula (1) and the second angle that is the ore terrace inclination angle is obtained in advance, and from the relationship information, The first angle corresponding to the second angle when the second angle satisfies the reference range is obtained, and the tilt angle of the revolving chute and the revolving chute are adjusted so as to satisfy the obtained first angle. The method of operating a blast furnace according to any one of (2) to (4), wherein the operation is performed by adjusting at least one of the number of revolutions of the revolving chute and the total number of revolutions of the revolving chute.

(6) Any one of (1) to (5), wherein the ore terrace inclination angle in each furnace radial direction is calculated based on the deposition shape of the ore layer obtained using a two-dimensional profile meter. The method of operating the blast furnace according to 1.

(7) Any one of (1) to (5), wherein the ore terrace inclination angle in each furnace radial direction is calculated based on the deposition shape of the ore layer obtained using a three-dimensional profile meter. The method of operating the blast furnace according to 1.

(8) A charging method control device used for operating a blast furnace in which an ore layer and a coke layer are alternately formed in layers in the furnace, and the deposition shape at the furnace top is inclined downward toward the center of the furnace, An acquisition unit that acquires the ore terrace inclination angles of the ore layer formed in the furnace in each of a plurality of furnace radial directions, and a representative value determined based on the plurality of ore terrace inclination angles acquired by the acquisition unit is used as an operation management index. and an operation control unit that operates so that the representative value satisfies the reference range.

(9) In a charging method control program used for operating a blast furnace in which an ore layer and a coke layer are alternately formed in layers in the furnace, and the deposition shape at the furnace top is inclined downward toward the center of the furnace, an acquisition step of acquiring the ore terrace inclination angles of the ore layer formed in the furnace in each of a plurality of furnace radial directions; and an operation step of operating so that the representative value satisfies the reference range, and a charging method control program for causing the process computer to execute.

According to the present invention, the occurrence of negative ore terraces can be suppressed. As a result, the layer thickness of the coke layer laminated on the ore layer is appropriately controlled, so that stable operation of the blast furnace can be realized.

1 is a schematic diagram of a blast furnace (bell-less blast furnace); FIG. FIG. 4 is an enlarged view near the furnace wall of the coke layer and ore layer deposited on the top of the in-furnace sediment layer. It is a functional block diagram of a charging method control device. 4 is a flow chart showing the sequence of a charging method control program; It is the data of the ore terrace inclination angle (°) in each direction before and after the improvement action is implemented.

FIG. 1 is a schematic diagram of a blast furnace used in a method of operating a blast furnace, which is one embodiment of the present invention. A blast furnace 1 is a bell-less blast furnace and includes a tuyere 2 , an annular tube 3 , a blow pipe 4 , a pulverized coal injection lance 5 , a turning chute 6 , a profile meter 7 , and a controller 8 . A plurality of tuyeres 2 are provided in the furnace lower part along the furnace circumferential direction of the blast furnace 1 . The annular pipe 3 is arranged so as to surround the lower part of the blast furnace 1 . The blow pipes 4 are intermittently provided in the circumferential direction of the annular tube 3 and connected to different tuyeres 2 respectively. The pulverized coal blowing lance 5 is inserted through each blow pipe 4 , and the tip of the pulverized coal blowing lance 5 extends inside each blow pipe 4 .

The turning chute 6 rotates around an axis extending in the vertical direction, and alternately charges the ore raw material and the coke raw material. The ore raw material and the coke raw material may each be charged in multiple batches, or each may be charged in one batch. Ore layers and coke layers are alternately formed in the furnace, and the raw material charging performed to form one ore layer is defined as ore charging, and this ore charging is achieved by one raw material charging. This is defined as "single dump charging", and achieving this ore charge by multiple raw material charging is defined as "multiple dump charging".

Sintered ore, pellets, lump ore, and non-calcined coal-containing agglomerate ore can be used as ore raw materials. The ore raw material may also contain substances other than ores (for example, reducing aids such as small coke). The coke raw material may contain fellow coke in addition to coke. The driving method of the revolving chute 6 may be forward tilting, reverse tilting, or a combination of forward tilting and reverse tilting. Note that forward tilting is a driving method in which the revolving chute 6 is driven from the furnace wall side toward the furnace center side.

A profile meter 7 acquires the deposition profile of the ore layer and the coke layer. Specifically, the profile meter 7 acquires a waveform of the distance between the profile meter 7 and the surface of the ore layer (or coke layer) for each measurement point. FIG. 2 is an enlarged view near the furnace wall of the coke layer and ore layer deposited on the uppermost part of the in-furnace sediment layer. Referring to FIG. 2, on the furnace wall side of the ore layer, an ore terrace indicated by symbol T is formed which is inclined at an inclination angle θ with respect to a horizontal plane (indicated by a dashed line in the figure) in the furnace radial direction. The inclination angle θ of this ore terrace is smaller than the repose angle of the ore. By controlling the turning chute 6, the magnitude of the inclination angle θ can be changed to adjust the thickness of the coke layer deposited on the ore terrace. The magnitude of the tilt angle θ is calculated by the controller 8, which will be described later.

A two-dimensional profile meter or a three-dimensional profile meter can be used for the profile meter 7 . In the case of a two-dimensional profilometer, a single measurement obtains the deposition shape in a specific furnace radial direction. Therefore, by installing a plurality of two-dimensional profile meters, it is possible to acquire the deposition shape of the ore layer in a plurality of furnace radial directions. Further, by providing a traveling mechanism for traveling the two-dimensional profile meter in the circumferential direction of the furnace, one two-dimensional profile meter can acquire the deposition shape of the ore layer in a plurality of furnace radial directions. In the case of using a two-dimensional profile meter, the deposition shape of the ore layer may be estimated by interpolating the deposition shape of the unmeasured region using the deposition shapes obtained in a plurality of furnace radial directions. .

The three-dimensional profile meter acquires the deposition shape of the ore layer in the furnace radial direction at every predetermined angle in the furnace circumferential direction. The measurement interval (predetermined angle) of the three-dimensional profile meter can be set appropriately. When the measurement interval of the three-dimensional profile meter is wide, interpolation processing may be performed to interpolate the deposited shape of the unmeasured area, as in the case of using the two-dimensional profile meter described above. In addition, the measurement data of the three-dimensional profile meter is not limited to that obtained according to the angle in the circumferential direction of the furnace. After that, it can be used in subsequent steps.

Here, acquisition of the deposition shape includes not only receiving raw measurement data from the profile meter 7, but also processing (for example, interpolating) the raw data as appropriate.

The controller 8 calculates the ore terrace inclination angle θ for each measurement direction based on the deposition shape of the ore layer acquired by the profile meter 7, and obtains the minimum value among the calculated ore terrace inclination angles θ. This minimum value of the ore terrace inclination angle θ can be used as a “representative value” described later.

The processing performed by the controller 8 can be realized by a program. A program prepared in advance for realizing various processing is stored in an auxiliary storage device, and a process computer such as a CPU executes the program stored in the auxiliary storage device. It is realized by reading the program into the main memory and executing the program read into the main memory by the process computer.

The program can also be provided to a process computer (eg, server) in a state recorded on a computer-readable recording medium. Examples of computer-readable recording media include optical disks such as CD-ROMs, phase change optical disks such as DVD-ROMs, magneto-optical disks such as MO (MagnetOptical) and MD (Mini Disk), floppy (registered trademark) disks and removable Examples include magnetic disks such as hard disks, compact flash (registered trademark), smart media, SD memory cards, memory cards such as memory sticks. Also included as a recording medium is a hardware device such as an integrated circuit (IC chip, etc.) specially designed and configured for the purposes of the present invention.

The present inventors discovered that by operating the blast furnace so that the inclination angle θ of the ore terrace is 0° or more, the uneven distribution of the reducing gas is suppressed and the stable operation of the blast furnace is realized. That is, when the inclination angle θ of the ore terrace is less than 0°, the variation in the thickness of the coke layer laminated on the ore layer in the furnace radial direction or the furnace circumferential direction increases as described above, and stable operation of the blast furnace is hindered. be. Therefore, the ore terrace inclination angle θ is obtained for each of a plurality of furnace radial directions, and the minimum value of these ore terrace inclination angles θ is used as a representative value, and the operation is performed so that the representative value is 0° or more (reference range). Stable operation of the blast furnace can be realized by performing management. When "whether or not the minimum value of the ore terrace inclination angle θ is 0° or more" is used as an operation control index, the measurement interval (predetermined interval) of the three-dimensional profile meter is set to, for example, 45 degrees or less. is preferred.

Here, the "plurality of furnace radial directions" refer to imaginary lines extending from the center of the furnace toward the furnace wall. On the furnace diameter, there are a first furnace radial direction extending from the furnace center toward the furnace wall and a second furnace extending from the furnace center toward the furnace wall and oriented 180 degrees different from the first furnace radial direction. In this specification, these two furnace radial directions existing on the furnace diameter are treated as independent furnace radial directions. Therefore, obtaining the ore terrace inclination angle for each of the first furnace radial direction and the second furnace radial direction aligned on the furnace diameter can also Get θ”.

The controller 8 can compare the ore terrace inclination angles θ in the respective furnace radial directions and use the minimum value as a representative value. By using the minimum value of the ore terrace inclination angle θ as a representative value, the smallest ore terrace inclination angle θ among the data obtained in each furnace radial direction is improved to 0° or more, so that the entire furnace circumferential direction You can shift towards the range. As a result, the above effect (uniform distribution of gas) can be enhanced. In addition, the uniformity of gas distribution may be improved by further implementing an action to make the ore terrace inclination angle θ uniform in each furnace radial direction.

Here, if the measurement interval of the ore terrace inclination angle θ is wide, the negative ore terrace may be overlooked. For example, even if the ore terrace inclination angles θ measured at intervals of 90° are all 0° or more, a negative ore terrace may exist between these measurement positions. In this case, the variation in the thickness of the coke layer laminated on the ore layer in the furnace radial direction or the furnace circumferential direction increases, and there is a risk that the stable operation of the blast furnace will be hindered. Therefore, the inventors of the present invention have studied an operation method that can be applied even when the measurement interval of the ore terrace inclination angle θ is wide, as follows.

Table 1 shows σ ^blast pressure (hPa) and permeability index ( -) and the ore terrace inclination angle (°). All results for run numbers 1-7 shown in Table 1 were measured and calculated at a specific orientation in the furnace. Table 1 also shows the inclination angle (°) of the coke terraces formed on the ore terraces.

・・・（A）
ただし、Ｐ_ＢおよびＰ_Ｔはそれぞれ送風圧力および炉頂圧力（ｋＰａ）、Ｖはボッシュガス量（Ｎｍ^３／分）である。 The σ blast pressure (hPa) and the permeability index (-) are indices that indicate the quality of the operating conditions of the blast furnace, and stable operation is realized when the σ blast pressure (hPa) and the permeability index (-) are low. can be considered to exist. The σ blast pressure (hPa) is the standard deviation in the time series change of the blast pressure. Blast pressure is the pressure of the hot air measured in front of the annular tube 3 . The permeability index (-) is the in-furnace ventilation resistance index (K), and can be calculated, for example, by the following formula (A).

... (A)
However, _PB and _PT are the blast pressure and furnace top pressure (kPa), respectively, and V is the bosh gas amount (Nm ³ /min).

For example, in the above operation results, one standard for stable operation (hereinafter referred to as , also referred to as “stable operating conditions”). That is, when the σ blast pressure (hPa) is 26 (hPa) or less and the permeability index (-) is 2.5 (-) or less, the reducing gas in the furnace is appropriately distributed, and the ore It can be considered that the raw material is uniformly reduced in the furnace radial direction. If the operation is not stable, the flow of the reducing gas is biased, so it is considered that the σ blow pressure (hPa) exceeds 26 (hPa) and the permeability index (-) exceeds 2.5 (-). be able to. Therefore, in the example of Table 1, the "stable operating conditions" can be set to "σ blast pressure: 26 (hPa)" and "air permeability index: 2.5 (-)". Based on Table 1, the minimum value of the ore terrace inclination angle θ when satisfying σ blow pressure of 26 (hPa) or less and air permeability index of 2.5 (−) or less is more than 4°.

Here, the present inventors found that in operation numbers 5 to 7 in Table 1, although the ore terrace inclination angle θ was 2° to 4° (a value of 0° or more), the stable operation conditions were not satisfied. The reason was considered by a cold model test using a 1/3 bell-less tester. The 1/3 bell-less test apparatus is a 1/3 size model test apparatus (radius of about 1800 mm) of an actual furnace imitating a bell-less top charging apparatus. A cold model test revealed that the ore terrace inclination angle has a standard deviation of about 2° and a maximum variation of about 4° in the circumferential direction of the furnace. From the above experimental results, if the blast furnace is operated so that the minimum value of the acquired ore terrace inclination angle θ is 5° or more, the minus ore terrace will be overlooked even if the measurement interval of the ore terrace inclination angle θ is widened. Since there is a low possibility that the blast furnace will be

Also, the upper limit of the reference range of the ore terrace inclination angle θ is not particularly limited, but can be appropriately set based on the angle of repose of the ore. For example, when the repose angle of ore is 27°, the upper limit of the reference range of the ore terrace inclination angle θ can be set to 26° or less. The angle of repose of ore varies depending on the components contained in the ore.

If the minimum value of the ore terrace slope angle θ does not meet the reference range, the controller 8 implements improvement actions to improve it. Controller 8 may implement any of the following improvement actions 1-3. However, these improvement actions 1 to 3 are examples, and the present invention is not limited to them.

(Improvement action 1)
In the ore dump, shift all notches to the furnace wall side by 1 notch and change to outward swing. By shifting all the notches toward the furnace wall by one notch, the ore raw material is charged in a region closer to the furnace wall, so that the ore terrace inclination angle θ can be increased.

(Improvement action 2)
Lower the blast furnace stock line. By lowering the stock line, the ore raw material charged to the furnace wall side increases, so the ore terrace inclination angle θ can be increased.

(Improvement action 3)
The improvement action 3 consists of (A) to (C) below.
(A) The relationship (hereinafter also referred to as relationship information) between the first angle calculated based on the following formula (1) and the second angle, which is the ore terrace inclination angle, is obtained in advance. The relevant information may be obtained based on the operational performance, or may be obtained based on the test results of an experimental apparatus (for example, the 1/3 bell-less test apparatus described above).
(B) From the relationship information, obtain the first angle corresponding to the second angle when the second angle satisfies the reference range (0° or more or 5° or more in the above embodiment).
(C) At least one of the tilt angle of the revolving chute, the number of revolutions of the revolving chute, and the total number of revolutions of the revolving chute is adjusted so as to satisfy the first angle obtained in (B).
Here, in equation (1), n is the total number of notches of the revolving chute provided in the blast furnace, k is the notch number, θk is the tilting angle of the revolving chute at notch number k, and Sk is the number of revolutions of the revolving chute at notch number k. , and let T be the total number of turns of the turning chute.

The notch number is a numerical value indicating the preset tilt angle of the revolving chute 6. As the notch number k increases, the charged raw material moves toward the center of the furnace, and as the value decreases, the raw material moves toward the furnace wall. means to be loaded. An example of the notch number k and the number of turns Sk is shown.

By operating the blast furnace as described above, the ore raw material charged to the furnace wall side increases, so the ore terrace inclination angle θ can be increased.

Although the bell-less blast furnace has been described as an example in this embodiment, the present invention can also be applied to a bell blast furnace. In the case of a bell blast furnace, improvement actions can be taken by adjusting the angle of the movable armor that collides with the ore material falling in the furnace and correcting the falling trajectory, or by adjusting the opening speed of the bell.

After the improvement action is taken, it is judged again whether the minimum value of the ore terrace inclination angle θ satisfies the reference range. As a result, if the minimum value of the ore terrace inclination angle θ does not satisfy the reference range, further improvement action is taken. That is, the improvement action is repeatedly implemented until the minimum value of the ore terrace inclination angle θ satisfies the reference range.

According to another aspect, the present invention is implemented by a charging method control device shown in FIG. The charging method control device 10 has an acquisition unit 11 and an operation control unit 12 . The obtaining unit 11 obtains the ore terrace inclination angle of the ore layer formed in the furnace in each of a plurality of furnace radial directions. That is, the obtaining unit 11 obtains the deposition shape of the ore layer and calculates the ore terrace inclination angle in each furnace radial direction. Acquisition unit 11 is implemented by cooperation of profile meter 7 and controller 8 . The operation control unit 12 uses the minimum value (representative value) among the plurality of ore terrace inclination angles acquired by the acquisition unit 11 as an operation management index, and operates so that this minimum value satisfies the reference range. The operation control section 12 is implemented by the controller 8 . Since the details of the processing have been described above, the description will not be repeated.

FIG. 4 is a flow chart showing the processing implemented by the above program. Since the explanation is redundant, only the outline of the processing will be explained. The acquisition unit 11 (profile meter 7) acquires the deposition shape of the ore layer (step S101). The acquisition unit 11 (controller 8) calculates the ore terrace inclination angle θ in each furnace radial direction based on the acquired deposition shape (step S102). The operation control unit 12 (controller 8) determines the minimum value of the plurality of calculated ore terrace inclination angles as a representative value (step S103). The operation control unit 12 (controller 8) determines whether the determined representative value satisfies the reference range (step S104). If the representative value satisfies the reference range (step S104 Yes), the process is terminated. If the representative value does not satisfy the reference range (step S104 No), the process proceeds to step S105. In step S105, the operation control part 12 (controller 8) performs the action mentioned above, and a process returns to step S101. Note that steps S101 to S102 correspond to the "acquisition step" recited in claim 9, and steps S103 to S105 correspond to the "operation step" recited in claim 9.

The method of operating a blast furnace according to the present invention will be described in detail with reference to examples. Using a 1/3 bell-less test apparatus, blast furnace raw materials were charged in layers under the same conditions as in an actual blast furnace, and ore terrace inclination angles (°) in multiple furnace radial directions were investigated. The 1/3 bell-less test apparatus has been described above and will not be described again. The average grain size of the blast furnace raw material was about 1/3 that of the actual furnace, and the charging amount was about 1/27 that of the actual furnace. Coke was charged at one dump per charge, and the amount of coke charged per charge was about 1.3 t. Also, the ore was charged at one dump per charge, and the amount of ore charged per charge was about 7.3 tons.

The deposition shape of the ore layer was measured with a three-dimensional profile meter, and the measured three-dimensional deposition shape was cut out at intervals of 10° in the furnace circumferential direction to obtain the deposition shape in each direction (corresponding to the furnace radial direction). After obtaining the deposition shape in each direction, the ore terrace inclination angle (°) in each direction was calculated. The representative value was the minimum value of the ore terrace inclination angle (°). In FIG. 5, the ore terrace inclination angle (°) before and after the improvement action in each direction is plotted. In this embodiment, improvement action 3 described above was implemented.

Before the improvement action was taken, the minimum value of the ore terrace inclination angle was -1°, as indicated by the white plot (circle) in FIG. At this time, the first angle calculated by the above equation (1) was 47°. Therefore, in order to set it to 5° or more, from the relationship between the first angle and the second angle (corresponding to “relational information”), the second angle (5°) when the second angle satisfies the reference range Improvement action 3 was simulated by obtaining a first angle = 50°, and adjusting the inclination angle θ of the turning chute based on the equation (1) that satisfies this first angle (50°).

As a result, as indicated by black plots (circles) in FIG. 5, the minimum value of the ore terrace inclination angle was 5° (indicated by the dashed line) or more. That is, the ore terrace inclination angle satisfies the reference range in all directions.

Based on the results obtained by the 1/3 bell-less test equipment, an operation was performed with a different ore dump in the actual furnace, and it was examined whether or not the operation would be stable. The target blast furnace was a 4,000 to 5,000 m ³ class blast furnace, and was operated under the same charging conditions as before the improvement action in the 1/3 bell-less test. At this time, the minimum value of the ore terrace inclination angle was below the reference range (5°). , Improvement Action 3 was implemented. As a result, the fluctuation of the blast pressure in the entire furnace was reduced by 10%, and the ventilation resistance was also reduced by 2%.

1 Blast Furnace 2 Tuyere 3 Annular Pipe 4 Blow Pipe
5 pulverized coal injection lance 6 turning chute 7 profile meter 8 controller 10 charging method control device 11 acquisition unit 12 operation control unit

Claims (9)

In a method of operating a blast furnace in which an ore layer and a coke layer are alternately formed in the furnace and the deposition shape at the furnace top is inclined downward toward the center of the furnace,
Obtaining the ore terrace inclination angle of the ore layer formed in the furnace in each of a plurality of furnace radial directions,
A method of operating a blast furnace, wherein a representative value determined based on the obtained plurality of ore terrace inclination angles is used as an operation management index, and the operation is performed so that the representative value satisfies a reference range. 2. The method of operating a blast furnace according to claim 1, wherein said representative value is a minimum value among said plurality of acquired ore terrace inclination angles. 3. The method of operating a blast furnace according to claim 2, wherein the reference range is 0[deg.] or more. 3. The method of operating a blast furnace according to claim 2, wherein the reference range is 5[deg.] or more. The total number of notches of the turning chute provided in the blast furnace is n,
k the notch number,
θk is the tilting angle of the revolving chute at notch number k,
Sk the number of turns of the turning chute at notch number k,
Assuming that the total number of turns of the turning chute is T,
Obtaining in advance relationship information that is the relationship between the first angle calculated based on the formula (1) and the second angle that is the ore terrace inclination angle,
obtaining the first angle corresponding to the second angle when the second angle satisfies the reference range from the relationship information;
In order to satisfy the obtained first angle, at least one of the tilting angle of the revolving chute, the number of revolutions of the revolving chute, and the total number of revolutions of the revolving chute is adjusted for operation. The method of operating a blast furnace according to any one of.

The blast furnace according to any one of claims 1 to 5, wherein the ore terrace inclination angle in each furnace radial direction is calculated based on the deposition shape of the ore layer obtained using a two-dimensional profile meter. method of operation. The blast furnace according to any one of claims 1 to 5, wherein the ore terrace inclination angle in each furnace radial direction is calculated based on the deposition shape of the ore layer obtained using a three-dimensional profile meter. method of operation. In a charging method control device used for blast furnace operation in which an ore layer and a coke layer are alternately formed in layers in the furnace, and the deposition shape at the furnace top is inclined downward toward the center of the furnace,
an acquisition unit that acquires the ore terrace inclination angle of the ore layer formed in the furnace in each of a plurality of furnace radial directions;
An operation control unit that uses a representative value determined based on the plurality of ore terrace inclination angles acquired by the acquisition unit as an operation management index, and operates such that the representative value satisfies a reference range;
A charging method control device having In a charging method control program used for blast furnace operation in which an ore layer and a coke layer are alternately formed in layers in the furnace, and the deposition shape at the furnace top is inclined downward toward the furnace center side,
an obtaining step of obtaining ore terrace inclination angles of ore layers formed in the furnace in each of a plurality of furnace radial directions;
an operation step of operating so that the representative value determined based on the plurality of ore terrace inclination angles obtained in the obtaining step is used as an operation management index, and the representative value satisfies a reference range;
A charging method control program for causing the process computer to execute

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