JP-2026076119-A - Blast furnace operation methods

Abstract

[Problem] To accurately calculate the desired ore layer thickness ratio that sets multiple operational indicators to predetermined targets. [Solution] The method for operating a blast furnace includes the steps of: obtaining an operation command to bring an operational indicator showing the state of the blast furnace within a target range; and calculating target operating conditions, which are operating conditions that bring the difference between the operational indicator after changing the operating conditions and the target operational indicator included in the operation command within a predetermined range, based on an operational indicator estimation model that takes operating conditions as input and operational indicators as output. The operation command includes target operating indicators for two or more operational indicators, where the target operating indicator for one of the two or more operational indicators maximizes, minimizes, or sets the operational indicator to a predetermined value, where the target operating indicator for the other of the two or more operational indicators sets the target operating indicator to a predetermined value, greater than or equal to a predetermined value, or less than or equal to a predetermined value; and the operating conditions include the distribution of ore layer thickness ratios. [Selection Diagram] Figure 1

Inventors

• 西村 隆
• 山本 哲也
• 齋藤 涼

Assignees

• ＪＦＥスチール株式会社

Dates

Publication Date

20260511

Application Date

20251006

Priority Date

20241023

Claims (8)

1. The steps include obtaining an operational command to bring the operational indicators showing the state of the blast furnace while it is in operation within a target range, A step of calculating target operating conditions, which are the operating conditions after changing the operating conditions, and which are the operating conditions included in the operation command, based on an operation indicator estimation model that takes operating conditions, which are the conditions for operating the blast furnace, as input and the operation indicator as output, so that the difference between the operation indicator after changing the operating conditions and the target operation indicator included in the operation command is within a predetermined range. Includes, The aforementioned operational command includes the aforementioned target operational indicators for two or more of the aforementioned operational indicators, The target operating indicator for one of the two or more operating indicators is to maximize, minimize, or set the operating indicator to a predetermined value. The target operating indicator for the other operating indicator among the two or more operating indicators is such that the target operating indicator is set to a predetermined value, greater than or equal to a predetermined value, or less than or equal to a predetermined value. The aforementioned operating conditions include the distribution of ore layer thickness ratios, and the method of operating a blast furnace.
2. A method for operating a blast furnace according to claim 1, further comprising the steps of presenting the calculated target operating conditions to the operator, or automatically changing the operating conditions based on the calculated target operating conditions.
3. The method for operating a blast furnace according to claim 1, wherein the operating indicator includes at least one of the aeration resistance index, gas utilization rate, heat load, and solution loss carbon amount.
4. The method for operating a blast furnace according to claim 1, wherein the operating conditions further include at least one of the following: oxygen enrichment rate, blast flow rate, iron production rate, pulverized coal ratio, heat flow ratio, sintered ore ratio, coke lump ratio, coke strength, sintered ore strength, sintered ore moisture content, blast temperature, and gas flow rate distribution within the blast furnace.
5. The blast furnace operation method according to claim 4, wherein the distribution of the ore layer thickness ratio, the distribution of the gas flow rate inside the blast furnace, and the distribution of the heat flow ratio have two or more values in the radial direction or cross-sectional direction inside the blast furnace, or are feature quantities indicating the distribution in the radial direction or cross-sectional direction inside the blast furnace calculated from the two or more values.
6. The method for operating a blast furnace according to claim 5, wherein the aforementioned feature quantity is a principal component score obtained by dimensionality reduction of the radial or cross-sectional distribution within the blast furnace using principal component analysis (PCA).
7. The method for operating a blast furnace according to claim 6, characterized in that the aforementioned feature quantities use the first to Nth principal components (where N is an integer including 5) whose cumulative contribution rate is 70% or more and 90% or less.
8. The blast furnace operation method according to claim 1, wherein the operational indicator estimation model is a model constructed based on the past operational performance of the blast furnace.

Description

This disclosure relates to a method for operating a blast furnace. Traditionally, when operating a blast furnace, operating conditions are sometimes specified to maintain an ideal state. One such operating condition is, for example, the ore layer thickness ratio. In a blast furnace, layers of ore and coke are stacked alternately, and the distribution shape of these layers significantly impacts the operation of the blast furnace. The distribution shape of the ore and coke layers charged into the blast furnace is controlled by the layer thickness ratio of the ore and coke layers in the radial direction of the furnace. The ore layer thickness ratio refers to the ratio of the thickness of the ore layer to the sum of the thicknesses of the ore and coke layers. The ore layer thickness ratio changes along the radial direction of the blast furnace, and even within the furnace cross-section (for example, a circular cross-section viewed from the top of the furnace), the layer thickness ratio differs depending on the location; therefore, it is treated as a distribution within the cross-section. For example, Patent Document 1 discloses a technique for defining a desirable range of ore layer thickness ratio in the furnace center region, intermediate region, and periphery region, and for achieving the ore layer thickness ratio within the defined desired range. Patent Document 1 describes how to achieve the defined desired range of ore layer thickness ratio by measuring the ore layer thickness ratio using a profile meter and, if necessary, changing the charging method from the charging chute. For example, Patent Document 2 discloses a technique for measuring whether the ore layer thickness ratio is within a certain range by using characteristic values selected from a group consisting of the maximum, minimum, and average values for each target location. If the ore layer thickness ratio is not within a certain range, the charging method is changed to bring the ore layer thickness ratio within that range. Japanese Patent Publication No. 2017-95761Japanese Patent Publication No. 2021-113341 This figure shows an example of an operating condition control device for executing a blast furnace operating method according to one embodiment of the present disclosure.This flowchart shows an example of a blast furnace operation method according to one embodiment of the present disclosure.This figure shows an example of the estimated results for the air permeability resistance index.This figure shows an example of an ore layer thickness ratio calculated based on an operational indicator estimation model.This figure shows an example of the air permeability resistance index when the ore layer thickness ratio is changed.This figure shows an example of gas utilization rates when the ore layer thickness ratio is changed.This figure shows an example of the distribution shape of the first to fifth principal components of the gas flow rate distribution inside the blast furnace.This figure shows an example of the prediction result of the airflow resistance index using the heat flux ratio distribution.This figure shows an example of the prediction results for the airflow resistance index using the gas flow rate distribution.This figure shows an example of the revised ore layer thickness ratio distribution calculated based on the operational instructions.This figure shows an example of the air permeability resistance index when the ore layer thickness ratio is changed.This figure shows an example of gas utilization rates when the ore layer thickness ratio is changed. The embodiments of this disclosure will be described below with reference to the drawings. Figure 1 shows an example of an operating condition control device 10 that implements a blast furnace operating method according to one embodiment of this disclosure. The operating condition control device 10 is a device that controls the operating conditions, which are the conditions under which the blast furnace 1 is operated. By controlling the operating conditions, the operating condition control device 10 can bring the operating indicators, which represent the state of the blast furnace 1, within a target range. The operating conditions for operating blast furnace 1 include the distribution of the ore layer thickness ratio. Blast furnace 1 consists of alternating layers of ore and coke, and the ore layer thickness ratio is defined as the ratio of the thickness of the ore layer to the sum of the thicknesses of the ore and coke layers, as shown in equation (1) below. However, in equation (1), L R is the ore layer thickness ratio, L O is the thickness of the ore layer, and L C is the thickness of the coke layer. The operating conditions, in addition to the ore layer thickness ratio, further include at least one of the following: oxygen enrichment rate, blast flow rate, iron production rate, pulverized coal ratio, heat flow ratio, sintered ore ratio, small coke lump ratio, coke strength, sinte