Blast furnace operating equipment and blast furnace operating method

Abstract

Provided is an operation device that makes it possible to determine the restoration of the flow rate of blowing air in a wind reduction state of a blast furnace.　An operation device 1 is used for operation of a blast furnace 100, the operation device comprising a control unit 30. The control unit 30 executes a determination process using a determination index that includes at least an evaluation index for ventilation abnormality when a wind reduction state is attained upon detection of the ventilation abnormality in the blast furnace 100, and decides to perform a wind increase operation when the control unit 30 determines in the determination process that a predetermined condition is satisfied.

Description

Technical Field

[0001] The present disclosure relates to an operating device and an operating method used for the operation of a blast furnace. For example, the present disclosure relates to a technique for an operating method of a blast furnace process, more specifically, determining ventilation abnormalities in a blast furnace, and regarding the determination of the return of the blast flow rate in a state where the blast flow rate in the blast furnace has been reduced due to measures taken against the ventilation abnormalities, that is, in a state of reduced blast.

Background Art

[0002] Conventionally, techniques for detecting or predicting ventilation abnormalities so that the ventilation abnormalities do not become large in a blast furnace and reducing ventilation abnormalities such as blow-through by a reduced blast operation that reduces the blast flow rate in advance are known. For example, Patent Document 1 discloses an abnormality determination device for a blast furnace that can distinguish and determine an abnormal state of operation and an abnormal state of a sensor. For example, Patent Document 2 discloses an operation status evaluation system that, when operating a blast furnace, not only predicts the risk of blow-through but also predicts the scale when blow-through occurs, and displays the prediction result to an operator, thereby enabling more reliable prevention of troubles such as blow-through and a decrease in furnace heat accompanying the occurrence of blow-through.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When reducing airflow, for example, as described in Patent Documents 1 and 2, ventilation abnormalities are determined using an index indicating the degree of ventilation abnormality based on statistical methods and a rule-based "blowing score," and then airflow is reduced. On the other hand, regarding restoring the airflow rate after airflow reduction, no clear method, such as the timing of restoration, has been considered in the prior art, and currently, the reduced airflow rate is restored based on the operator's judgment or other factors.

[0005] This disclosure has been made in view of the above-mentioned problems, and aims to provide an operating device and operating method that enables determination of the return of the airflow rate when the blast furnace is in a reduced airflow state. [Means for solving the problem]

[0006] (1) An operating apparatus according to one embodiment of the present disclosure, Operating equipment used in the operation of a blast furnace, It includes a control unit, and the control unit is When a reduced airflow state is detected in the blast furnace due to an abnormality in ventilation, a determination process is executed using a determination index that includes at least an evaluation index for the abnormality in ventilation. If the determination process determines that the predetermined conditions are met, the airflow increase operation is decided.

[0007] (2) As one embodiment of the present disclosure, in (1), The aforementioned evaluation index includes a Q statistic based on principal component analysis using the output values ​​of the shaft pressure sensor group installed around the blast furnace body as input.

[0008] (3) As one embodiment of the present disclosure, in (2), The aforementioned predetermined conditions include a first condition that the Q statistic is less than or equal to a first threshold.

[0009] (4) As one embodiment of the present disclosure, in (3), If the control unit determines that the first condition is not met and that the Q statistic is on an increasing trend, it performs a reduction in airflow.

[0010] (5) In one embodiment of the present disclosure, in any of (1) to (4), The aforementioned determination index further includes the time elapsed since the reduced airflow state was established. The aforementioned predetermined condition includes a second condition that the time is equal to or greater than a second threshold.

[0011] (6) In one embodiment of the present disclosure, in any of (1) to (5), The aforementioned determination index further includes the furnace top temperature of the blast furnace, The aforementioned predetermined conditions include a third condition that the furnace top temperature is below a third threshold.

[0012] (7) In one embodiment of the present disclosure, in any of (1) to (6), The aforementioned determination index further includes the gas utilization rate in the blast furnace, The aforementioned predetermined conditions include a fourth condition, which is that the gas utilization rate is between a fourth threshold and a fifth threshold.

[0013] (8) In one embodiment of the present disclosure, in any of (1) to (7), If the control unit determines in the determination process that the predetermined conditions have been met, it restores the airflow rate to the normal state by the airflow increase operation.

[0014] (9) In one embodiment of the present disclosure, in any of (1) to (8), A sensor unit used to acquire the aforementioned judgment index, A storage unit that stores data acquired by the sensor unit, Furthermore, The control unit calculates the determination index by referring to the data stored in the storage unit, and uses the calculated determination index to determine whether or not predetermined conditions have been met in the determination process.

[0015] (10) An operating method according to one embodiment of the present disclosure is A method of operation used in the operation of a blast furnace, When the blast volume is reduced due to the detection of abnormal ventilation in the blast furnace, a determination process using a determination index including at least an evaluation index of abnormal ventilation is executed. When it is determined that a predetermined condition is satisfied in the determination process, an operation of increasing the blast volume is determined. It includes.

[0016] (11) As one embodiment of the present disclosure, in (10), The evaluation index includes a Q statistic based on principal component analysis with the output values of a shaft pressure sensor group installed around the furnace body of the blast furnace as input.

[0017] (12) As one embodiment of the present disclosure, in (11), [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​This is a block diagram showing an example of the configuration of an operating apparatus according to one embodiment of the present disclosure. [Figure 3] Figure 2 is a flowchart illustrating an example of the operation of the operating equipment. [Figure 4] Figure 2 is the first graph illustrating an example of the operation of the operating equipment. [Figure 5] This is the second graph illustrating an example of the operation of the operating equipment shown in Figure 2. [Modes for carrying out the invention]

[0022] This section provides a more detailed explanation of the background and problems of conventional technologies.

[0023] As mentioned above, methods for predicting or detecting open-air ventilation anomalies have been proposed in the past. In these conventional technologies, the timing of the anomaly is indicated and airflow is reduced. On the other hand, in the recovery trend from an abnormal operating state indicating ventilation anomalies such as open-air ventilation to a normal operating state indicating normal ventilation, the method for determining the appropriate timing to restore the reduced airflow to the original flow rate has not been sufficiently considered.

[0024] In blast furnaces, the airflow rate is directly linked to production volume, and a delay in restoring the airflow can lead to a decrease in molten iron production. On the other hand, restoring the airflow rate too early, even when furnace conditions such as ventilation are poor, can further worsen the furnace conditions. As a result, further air reduction may be necessary, requiring prolonged air reduction. Forcing a restoration of the airflow rate can lead to a significant deterioration of furnace conditions, increasing the risk of equipment malfunctions due to large blow-throughs and other issues.

[0025] The following provides a more detailed explanation of the problems that this invention aims to solve.

[0026] Shaft pressure gauges are positioned both vertically and circumferentially around the blast furnace body. Pressure is applied to the outer surface layer of the raw material inside the furnace, and a phenomenon occurs where this pressure is released. At this time, there is a high possibility that a localized ventilation abnormality due to a so-called "small blow-through" is occurring inside the blast furnace. In this disclosure, the above-described condition is defined as a "small blow-through." In blast furnace operation, in order to protect the blast furnace body, if the pressure inside the furnace suddenly increases, a pressure valve located at the top of the furnace is opened. In blast furnace operation, this is usually referred to as a "blow-through," but in this disclosure, to distinguish it from such a "blow-through," the example of a ventilation abnormality is described as a "small blow-through."

[0027] Even a small void can cause localized collapse of the raw materials stacked in layers inside the blast furnace. If the localized collapse is large, and the airflow is restored without resolving the localized collapse, a negative operational cycle can occur where further small voids are created, leading to further collapse of the raw materials. This could potentially force a long-term reduction in production.

[0028] To address the above-mentioned problems, it is not necessarily appropriate to restore the reduced airflow simply because an index indicating the degree of ventilation abnormality, such as a rule-based "open airflow score" intended for predicting or detecting open airflow, falls below the threshold for the risk of open airflow occurring. Unless a different judgment process is performed to restore the airflow rate, it is not easy to appropriately determine and operate the restoration of the airflow rate.

[0029] This disclosure aims to provide an operating device and operating method that enable the determination of the return of the airflow rate when the blast furnace is in a reduced-air state, in order to solve the problems described above. For example, this disclosure proposes a new method for determining the timing of returning the airflow rate after a reduction in airflow.

[0030] Hereinafter, with reference to the attached drawings, an example of the configuration and operation of the operating device 1 according to one embodiment of the present disclosure will be mainly described. Figure 1 is a schematic diagram showing the sensor unit 10 of the operating device 1 according to one embodiment of the present disclosure, which is arranged in relation to the blast furnace 100. Figure 2 is a block diagram showing an example of the configuration of the operating device 1 according to one embodiment of the present disclosure. As shown in Figure 2, the operating device 1 has a sensor unit 10, a storage unit 20, a control unit 30, and an output unit 40.

[0031] As shown in Figure 1, a tuyere 110 for adjusting the airflow rate inside the blast furnace 100 is located at the bottom of the blast furnace 100 as an operating terminal related to the operating device 1. Under normal operating conditions of the blast furnace 100, high-temperature air is blown into the furnace from the tuyere 110. If an abnormality in ventilation is detected, the airflow rate is reduced by the tuyere 110, and the reduced airflow state is maintained until the ventilation condition is restored. If the control unit 30 determines, through a determination process described later, that it is acceptable to return the airflow rate to normal, the airflow rate is increased by the tuyere 110.

[0032] The sensor unit 10 has multiple shaft pressure sensors 11 arranged in the height direction and circumferential direction around the furnace body of the blast furnace 100. The shaft pressure sensors 11 measure the pressure of the internal surface layer of the blast furnace 100. The sensor unit 10 has at least one furnace top gas thermometer 12 located at the top of the blast furnace 100. The sensor unit 10 has an exhaust gas meter 13 that measures the exhaust gas components of the gas that passes through the furnace of the blast furnace 100 and is discharged from the furnace top. The exhaust gas meter 13 measures gas components such as N2, H2, CO, and CO2. The exhaust gas meter 13 is located after a gas purification device 120 located relative to the furnace top of the blast furnace 100.

[0033] The sensor unit 10 is used to acquire a judgment index. The judgment index is used in the judgment process described later, which is performed by the control unit 30. In this disclosure, the "judgment index" includes, for example, an evaluation index for ventilation abnormalities. The "evaluation index" includes a Q statistic based on principal component analysis using the output values ​​of the shaft pressure sensor group 11 installed around the furnace body of the blast furnace 100 as input. In addition, the judgment index may further include the time elapsed since the blast furnace 100 entered a reduced airflow state. The judgment index may further include the furnace top temperature of the blast furnace 100 acquired using at least one furnace top gas thermometer 12. The judgment index may further include the gas utilization rate in the blast furnace 100 acquired using the exhaust gas meter 13. In this disclosure, the "gas utilization rate" is defined, for example, as exhaust gas CO2 / (exhaust gas CO2+exhaust gas CO).

[0034] As shown in Figure 2, the storage unit 20 includes an HDD (Hard Disk Drive), an SSD (Solid State Drive), and an EEPROM (Electrically Erasable Programmable Read-Only Memory). This includes memory modules such as ROM (Read-Only Memory) and RAM (Random Access Memory). The memory unit 20 may function as a main memory module, an auxiliary memory module, or a cache memory. The memory unit 20 is not limited to those built into the operating device 1, and may include storage media such as removable media. Such removable media include USB (Universal Serial Bus) memory, CD (Compact Disc), DVD (Digital Versatile Disc), and BD (Blu-ray® Disc).

[0035] The memory unit 20 stores information necessary to realize the operation of the operating device 1. The memory unit 20 stores information obtained through the operation of the operating device 1. For example, the memory unit 20 can store an operating system (OS), various programs, and various data. The memory unit 20 stores data acquired by the sensor unit 10. For example, the memory unit 20 collects and stores the sensor values ​​of the shaft pressure sensor 11, the top gas thermometer 12, and the exhaust gas meter 13 installed after the gas purification device 120, all of which are installed in the furnace body of the blast furnace 100, as measured values. In addition, the memory unit 20 also collects and stores the sensor values ​​of the airflow meter, which is attached to the blast furnace 100 and measures the airflow rate inside the blast furnace 100, as measured values.

[0036] The control unit 30 includes one or more processors, one or more programmable circuits, one or more dedicated circuits, or a combination thereof. In this disclosure, "processor" means a general-purpose processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). A processor, or a dedicated processor specialized for a particular process, is not limited to these. "Programmable circuitry" is, for example, an FPGA (Field-Programmable Gate Array). However, it is not limited to this. "Dedicated circuit" is, for example, an ASIC (Application Specific Integrated Circuit). The control unit 30 is stored in the storage unit 20 The control unit 30 calculates a judgment index by referring to the data, and uses the calculated judgment index to determine whether or not predetermined conditions are met in the judgment process described later. The control unit 30 has a calculation unit 31 and a determination unit 32.

[0037] The calculation unit 31 refers to the storage unit 20, which stores data from the sensor group of the sensor unit 10, and calculates the judgment indicators described above. For example, the calculation unit 31 refers to data from the group of shaft pressure sensors 11 installed around the furnace body of the blast furnace 100 and calculates a Q statistic based on principal component analysis as an evaluation indicator for ventilation abnormalities. For example, the calculation unit 31 may refer to data from at least one top gas thermometer 12 and calculate the top temperature of the blast furnace 100 as an average value. For example, the calculation unit 31 may refer to data from the exhaust gas meter 13 and calculate the gas utilization rate in the blast furnace 100. In addition, the calculation unit 31 may also calculate the time that has elapsed since the blast furnace 100 entered a reduced airflow state.

[0038] When the determination unit 32 detects an abnormality in the ventilation of the blast furnace 100 and enters a reduced airflow state, it executes the determination process described below using the determination index calculated by the calculation unit 31. If the determination unit 32 determines that predetermined conditions have been met in the determination process, it decides to increase the airflow. The determination unit 32 determines whether or not to restore the airflow rate according to the determination flow in the determination process.

[0039] In this disclosure, “predetermined conditions” include at least a first condition, which is that the Q statistic, an evaluation index for ventilation abnormalities, is below a first threshold. In addition, the predetermined conditions may further include a second condition, which is that the time elapsed since the reduced airflow state was established is above a second threshold. The predetermined conditions may further include a third condition, which is that the top temperature of the blast furnace 100 is below a third threshold. The predetermined conditions may further include a fourth condition, which is that the gas utilization rate is above a fourth threshold and below a fifth threshold.

[0040] The output unit 40 includes one or more output interfaces that output information to the user. These output interfaces include a display that visually outputs information as an image, a speaker that audibly outputs information as sound, and a vibrator that tactilely outputs information as vibration. For example, if the determination unit 32 determines that the airflow rate should be restored, the output unit 40 displays a visual message on the display indicating that the airflow rate should be restored and instructs the operator to restore the airflow rate.

[0041] In the operation of the blast furnace 100, the operating device 1 uses at least the above-described evaluation index for ventilation abnormalities as a judgment index when reducing the airflow according to an index for detecting ventilation abnormalities and then restoring the reduced airflow. In addition, the operating device 1 may further use at least one of the elapsed time after airflow reduction, furnace top temperature, and gas utilization rate. In this disclosure, in order for the control unit 30 to perform an appropriate determination of airflow reduction and restoration, judgment indexes to be adopted for each factor causing the ventilation abnormality that led to the airflow reduction have been newly identified from phenomena and operational data. The rationale for the judgment indexes adopted in this disclosure is described below.

[0042] This section explains the evaluation index for abnormal ventilation. The evaluation index represents the abnormal state of ventilation inside the blast furnace 100. Therefore, when the airflow rate is restored after the air reduction, the evaluation index must be below the first threshold for abnormality determination that has been set. As an evaluation index representing abnormal ventilation, the above-mentioned Q statistic value, which can unify the variation in the shaft pressure group that can detect the ventilation state inside the blast furnace 100 at an early stage, can be considered.

[0043] Next, we will explain the time elapsed since the reduced airflow condition began. As mentioned above, when the measured values ​​of multiple shaft pressure sensors 11 at different heights in the same direction rise and then fall, it indicates that the pressure locally increased inside the blast furnace 100, and then decreased. In the case of such a small blow-through, it is assumed that pressure was applied to the layers of raw materials and coke piled inside the blast furnace 100, and the pressure decreased when they collapsed. In such cases, the effect lasts longer than in other cases, and continues until the collapsed layers reach the lower part of the furnace, or at least the fusion zone. Therefore, even if indicators showing abnormal ventilation and the "blow-through score" appear to return to normal, they may worsen again after some time has passed. Consequently, when restoring the reduced airflow rate, it is necessary to consider observing the conditions inside the blast furnace 100 over a certain period of time.

[0044] Next, let's discuss the furnace top temperature. The furnace top gas thermometer 12, installed above the raw material charging surface at the top of the blast furnace 100, may experience a temperature increase. This is due to changes in the distribution of the charged raw materials caused by the collapse of the raw material layer due to small blow-throughs, i.e., changes in the gas flow distribution inside the furnace. As a result, the high-temperature gas blown in from the tuyere 110 does not properly exchange heat with the raw materials, and reactions such as reduction and heating of the raw materials do not occur sufficiently. When the heat exchange between the blast furnace gas and the raw materials is small, it is expected that the gas will rise to the top of the furnace while remaining at a relatively high temperature. In this case, the gas flow often passes relatively close to the center of the furnace circumference. Therefore, the measurement value of the shaft pressure sensor 11 installed on the outer circumference of the blast furnace 100 may not easily reflect this change. Consequently, it may not be easy to determine whether to restore the reduced airflow state based solely on the shaft pressure value.

[0045] As described above, the furnace top temperature is an indicator that reflects, to some extent, the state of material deposition inside the blast furnace 100, including the circumferential center. When restoring the reduced airflow rate, it is important to observe the furnace top temperature, which represents the history of gas passage through the furnace, for example, by controlling it using an upper limit for the furnace top temperature.

[0046] Next, let's discuss the gas utilization rate. In abnormal conditions where the gas flow near the center of the blast furnace 100 increases, the gas components generated from the blast furnace 100, such as the gas utilization rate mentioned above, decrease. When a large amount of gas passes through the center of the furnace, where there is less ore charging, due to disturbances in the raw material distribution in the blast furnace 100 and deterioration of the gas flow in the lower part of the furnace, the opportunities for contact with the ore decrease, and the reduction of the ore decreases. As a result, the gas utilization rate is thought to decrease. A high gas utilization rate means that the iron ore is being reduced more efficiently. Therefore, it is desirable from an operational standpoint, but if the gas utilization rate is higher than in normal stable operating conditions, it is possible that the gas utilization rate is high due to a reduction in permeability. Therefore, it is desirable to set an appropriate upper limit. As described above, the gas utilization rate is also a result of gas passing through the blast furnace 100 and reactions such as reduction taking place, so it is an important indicator for determining when to restore the airflow rate that has decreased due to reduced airflow.

[0047] Figure 3 is a flowchart illustrating an example of the operation of the operating device 1 shown in Figure 2. Referring to Figure 3, we will mainly explain an example of the flow of the determination process for deciding on an airflow increase operation, which is performed by the control unit 30 of the operating device 1.

[0048] In step S101, the control unit 30 determines whether or not it has detected an abnormal ventilation in the blast furnace 100. For example, the control unit 30 determines whether or not a small blow-through has occurred in the blast furnace 100. For example, the control unit 30 may detect a small blow-through based on prior art as shown in Patent Document 1. However, it is not limited to this, and the control unit 30 may predict a small blow-through based on similar art. If the control unit 30 determines that it has detected an abnormal ventilation, it executes the process in step S102. If the control unit 30 determines that it has not detected an abnormal ventilation, it repeats the process from step S101. The control unit 30 maintains the current ventilation state in the blast furnace 100.

[0049] In step S102, if the control unit 30 determines that it has detected an abnormality in ventilation in step S101, it executes a blast reduction operation in the blast furnace 100. For example, the control unit 30 may control the blast nozzle 110, which is the operating end in the blast furnace 100, so as to reduce the airflow rate inside the blast furnace 100. The control unit 30 is not limited to the above configuration in which the operating device 1 itself automatically controls the blast nozzle 110, but may also be configured to output a blast reduction instruction to the operator from the output unit 40 to prompt the operator to perform a blast reduction operation.

[0050] In step S103, the determination unit 32 of the control unit 30 determines whether the time elapsed since the reduced airflow state was established by the reduced airflow operation in step S102 is equal to or greater than the second threshold. The determination unit 32 determines whether the second condition is met. If the determination unit 32 determines that the elapsed time is equal to or greater than the second threshold, it executes the process in step S104. If the determination unit 32 determines that the elapsed time is less than the second threshold, it repeats the process from step S103. In step S103 after the reduced airflow operation, the control unit 30 temporarily waits for a certain amount of time to pass before proceeding with the determination process. This is because the blast furnace 100 is a system with a large reaction time constant, and the degree of influence of the operation (ventilation) of a small blowhole cannot be determined until a certain amount of time has passed.

[0051] In step S104, if the determination unit 32 of the control unit 30 determines in step S103 that the elapsed time is equal to or greater than the second threshold, it determines whether the Q statistic calculated by the calculation unit 31 is equal to or less than the first threshold. The determination unit 32 determines whether the first condition is met. If the determination unit 32 determines that the Q statistic is equal to or less than the first threshold, it executes the process in step S106. If the determination unit 32 determines that the Q statistic is greater than the first threshold, it executes the process in step S105.

[0052] In step S105, if the determination unit 32 of the control unit 30 determines in step S104 that the Q statistic is greater than the first threshold, it determines whether the Q statistic is on an increasing trend. If the determination unit 32 determines that the Q statistic is on an increasing trend, it repeats the process from step S102. If the determination unit 32 of the control unit 30 determines in step S104 that the first condition is not met and in step S105 that the Q statistic is on an increasing trend, it performs the airflow reduction operation again in step S102. If the determination unit 32 determines that the Q statistic is not on an increasing trend, it repeats the process from step S104. If the determination unit 32 of the control unit 30 determines in step S104 that the first condition is not met and in step S105 that the Q statistic is not on an increasing trend, it maintains the current airflow reduction state.

[0053] In step S106, if the determination unit 32 of the control unit 30 determines in step S104 that the Q statistic is less than or equal to the first threshold, it determines whether the furnace top temperature calculated by the calculation unit 31 is less than or equal to the third threshold. The determination unit 32 determines whether the third condition is met. If the determination unit 32 determines that the furnace top temperature is less than or equal to the third threshold, it executes the process in step S107. If the determination unit 32 determines that the furnace top temperature is greater than the third threshold, it repeats the process from step S104. The determination unit 32 of the control unit 30 maintains the current reduced airflow state.

[0054] In step S107, if the determination unit 32 of the control unit 30 determines in step S106 that the furnace top temperature is below the third threshold, it determines whether the gas utilization rate calculated by the calculation unit 31 is between the fourth threshold and the fifth threshold. The determination unit 32 determines whether the fourth condition is met. The determination unit 32 determines whether the gas utilization rate is within a predetermined range between the fourth threshold and the fifth threshold. If the determination unit 32 determines that the gas utilization rate is within the predetermined range, it executes the process in step S108. If the determination unit 32 determines that the gas utilization rate is not within the predetermined range, it repeats the process from step S104. The determination unit 32 of the control unit 30 maintains the current reduced airflow state.

[0055] In step S108, the determination unit 32 of the control unit 30 determines that predetermined conditions, including all of the first, second, third, and fourth conditions, have been met in the above determination process, and decides to increase the airflow. For example, the control unit 30 prompts the operator to increase the airflow by outputting an instruction to increase the airflow from the output unit 40. However, it is not limited to this, and for example, the control unit 30 may automatically control the tuyere 110, which is the operating end in the blast furnace 100, using the operating device 1 itself, so as to increase the airflow rate inside the blast furnace 100. For example, if the control unit 30 determines that predetermined conditions have been met in the above determination process, it may restore the airflow rate to the normal state by increasing the airflow using the operating device 1 itself. If the airflow reduction operation is performed multiple times through the process in step S102 via step S105, it is preferable to gradually restore the reduced airflow by dividing the airflow increase operation into several steps, but it is not limited to this, and all the reduced airflow may be comprehensively restored in a single airflow increase operation.

[0056] Figure 4 is the first graph illustrating an example of the operation of the operating apparatus 1 in Figure 2. Figure 4 conceptually shows the contents of the process in step S105 of Figure 3. The contents of the process in step S105 of Figure 3 will be explained in more detail with reference to Figure 4.

[0057] In step S105, the determination unit 32 of the control unit 30 further compares the Q statistic with two additional thresholds. These thresholds include a seventh threshold Th7 which is greater than the first threshold in step S104, and a sixth threshold Th6 which is even greater than the seventh threshold Th7. The determination unit 32 determines that the Q statistic is on an increasing trend if the Q statistic value increases and exceeds the sixth threshold Th6. The determination unit 32 also determines that the Q statistic is on an increasing trend if the Q statistic value exceeds the seventh threshold Th7, which is lower than the sixth threshold Th6, for a certain period of time T or longer.

[0058] The configuration and processing of the operating apparatus 1 shown in Figure 2 will be described in detail below, with specific numerical examples, but this disclosure is not limited in any way to the following examples. The numerical values ​​described below are merely examples and do not limit the scope of this disclosure. The scope of this disclosure should be determined solely based on the claims.

[0059] The elapsed time after airflow reduction, which is the judgment indicator in step S103 of Figure 3, may be included in the range of 15 to 60 minutes, for example. Immediately after reducing airflow, it is not easy to determine whether the abnormal ventilation phenomenon that caused the reduction in airflow will be resolved or continue. Even if the shaft pressure group appears stable at first glance, it is possible that the ventilation condition will deteriorate afterward due to the descent of a small open area. Therefore, it is preferable to wait at least 15 minutes before increasing airflow. Accordingly, the lower limit of the elapsed time was set to 15 minutes.

[0060] On the other hand, if too much time is left between steps, the amount of molten iron produced will decrease by the amount of time elapsed. Therefore, if the predetermined conditions are met in the judgment process from step S103 onward, which uses judgment indicators related to the ventilation state, it is preferable to increase the airflow. Accordingly, the upper limit of the elapsed time was set to 60 minutes. In the example of this disclosure, the elapsed time was set to 30 minutes by referring to data from past small blow-throughs in the target blast furnace 100.

[0061] The Q statistic, which is the judgment index in step S104 of Figure 3, is a unified index of anomalies based on multiple shaft pressure sensors 11. In the example of this disclosure, the Q statistic, which is an index of the MSPC (Multivariate Statistical Process Control) method, is used as the unification method. This method expresses anomalies with fewer variables by aggregating the information from a large number of variables into orthogonal principal components based on the correlations between variables using Principal Component Analysis (PCA).

[0062] In operating device 1, the measured values ​​from the multiple shaft pressure sensors 11 used as input are a data set of shaft pressure as described above. The Q statistic and the principal component analysis that forms its basis will be explained according to operating device 1 and the target process.

[0063] Principal component analysis (PCA) is a mathematical process that replaces (reduces the dimensionality of) a small number of variables that best reflect the characteristics of the original data, while minimizing the loss of information from the original data set as much as possible. In the case of the data from the shaft pressure sensor 11, a total of 20 shaft pressure sensors 11 are installed on the furnace body of the blast furnace 100: 5 in the height direction and 4 in the circumferential direction. Let's assume that PCA is applied to the measured shaft pressure values ​​of up to 20 points and that they are replaced with a few variables (principal component values) that best reflect the characteristics of the 20 data points. The operating device 1 can more easily estimate the state inside the blast furnace 100 by monitoring only the small number of variables generated by PCA, without needing to observe all 20 data points.

[0064] Synchronization in a set of multiple (multi-dimensional) data means that the behavior of operational variables is coordinated with respect to the time progression or operational actions in a process. In the shaft pressure data for blast furnace 100 operation, the first principal component value, which has the largest variance in principal component analysis, reflects the effects of setting changes related to operational load, such as changes in the flow rate of injected gas. On the other hand, the second and subsequent components of the principal component analysis show components from other unstable periods. Operational device 1 performs a decision process using these components.

[0065] For example, principal component analysis is applied to the data from the 11 shaft pressure sensors installed at the top of the blast furnace 100, and the second principal component with the largest variance among the components exhibiting asynchronous behavior is calculated. This value becomes the Q statistic. However, if abnormal phenomena are significantly expressed in the third component and beyond, the values ​​of the third component and beyond may also be used.

[0066] In order to calculate the indexed Q statistic used in the judgment process of the operating device 1, first, principal component analysis is applied to the time series data of the shaft pressure sensor 11 for the normal operating section inside the blast furnace 100. The time series data of the second principal component z2 is then created. In the normal operating section, it is necessary to include data for the stability limit, that is, the limit at which the operation can be judged as normal.

[0067] Next, the maximum value of the second principal component z2 in the normal operating interval (time interval) described above is z 2,m ax The following is calculated. Calculating the maximum value of the second principal component for a normal time interval corresponds to calculating the maximum value of the fluctuation range of sensor data and the deviation from the normal operating range when normal operation is being performed, i.e., the value of the stability limit. When predicting an operational abnormality in the blast furnace 100, the determination is made using an index obtained by dividing the second principal component calculated from the sensor data of the operating range in which the abnormality is occurring by the maximum value of the second principal component calculated from the sensor data of the normal operating range. The first threshold for making the determination is made smaller than the threshold used for predicting or detecting blow-throughs. In the determination process of the operating device 1, the larger the value of the Q statistic used, the higher the degree of abnormality.

[0068] Let's explain the furnace top temperature, which is the judgment indicator in step S106 of Figure 3. The furnace top gas thermometers 12 that measure the furnace top temperature are often installed in multiple locations above the raw material charging surface of the blast furnace body 100. In the sensor unit 10 of the operating device 1, four furnace top gas thermometers 12 are installed for the target blast furnace 100. The furnace top temperature used as the judgment indicator in the judgment process of the operating device 1 may be the average value of the measurements obtained from the four furnace top gas thermometers 12. However, it is not limited to this, as the judgment process of the operating device 1 only requires that an average value of the furnace top temperature be obtained, so it is sufficient to have at least one furnace top gas thermometer 12 installed.

[0069] In addition, the furnace top temperature fluctuates up and down due to the influence of the timing of raw material charging from the top of the blast furnace 100. The calculation unit 31 of the control unit 30 may further use the above-mentioned time-moving average to reduce the influence of charging. The time used for the time-moving average should be longer than the batch interval of raw material charging, for example, around 10 minutes, and may be around 15 to 30 minutes. In the operation of the blast furnace 100 targeted by the operating device 1, a 15-minute time-moving average was adopted. In the blast furnace 100 targeted by the operating device 1, the upper limit of the furnace top temperature was set to 150% of the temperature during normal operation based on past operating data. Since the temperature during normal operation is approximately 100°C, the upper limit of the furnace top temperature is approximately 150°C.

[0070] The gas utilization rate, which is the judgment index in step S107 of Figure 3, will be explained. The gas utilization rate has several definitions, such as CO / CO2, but in this disclosure, it is defined as exhaust gas CO2 / (exhaust gas The gas emissions are defined as CO2 + CO2. The upper and lower limits that define the predetermined range of the gas utilization rate are determined by the operation. For the blast furnace 100 targeted by the operational equipment 1, the lower limit is set at 47% and the upper limit at 49%. The thresholds, including the fourth and fifth thresholds, were determined by analyzing past operational data.

[0071] Figure 5 is a second graph illustrating an example of the operation of the operating device 1 in Figure 2. Figure 5 schematically shows the timing at which an airflow increase instruction is output by the judgment process in Figure 3. Referring to Figure 5, we will mainly explain an example of the timing at which an airflow increase instruction is output by the judgment process in Figure 3.

[0072] In Figure 5, the data, from top to bottom, includes reference data for blast furnace 100's shaft pressure group, Q statistic values, gas utilization rate (%), and average furnace top temperature (°C). In this data, two cases, Case C1 and Case C2, are shown as the timing when a ventilation anomaly was detected. The circles in the figure indicate the timing when the conditions for restoring the airflow rate are met when a ventilation anomaly is detected and the airflow is reduced. The triangles in the figure indicate the timing when the conditions for restoring the airflow rate are not met when a ventilation anomaly is detected and the airflow is reduced.

[0073] In Case C1, after the Q statistic exceeds the threshold Th0 for open ventilation, and after a certain period of time of 30 minutes, the Q statistic falls below the first threshold Th1 included in the first condition, but the gas utilization rate is not within the predetermined range of the fourth threshold Th4 or higher and the fifth threshold Th5 or lower. For example, the gas utilization rate is below the fourth threshold Th4. Subsequently, when the gas utilization rate falls within the predetermined range, the Q statistic value exceeds the first threshold Th1. Similarly, the average furnace top temperature also exceeds the third threshold Th3. Subsequently, when the Q statistic falls below the first threshold and the conditions for the other judgment indicators are also met, the airflow increase instruction I1 is executed.

[0074] In Case C2, after the Q statistic exceeds the threshold Th0 for open-circuit detection, a certain period of time (30 minutes) elapses, and the Q statistic exceeds the first threshold Th1 included in the first condition. After further time has passed, when the Q statistic falls below the first threshold Th1, the average furnace top temperature is still above the third threshold Th3. Subsequently, when the average furnace top temperature falls below the third threshold Th3 and the conditions for the other indicators are also met, the airflow increase instruction I2 is executed.

[0075] According to the operating device 1 of the above embodiment, it is possible to determine the restoration of the airflow rate when the blast furnace 100 is in a reduced airflow state. As a result, the operating device 1 can also provide the operator with an appropriate timing for increasing the airflow when the airflow is reduced due to a ventilation abnormality. Consequently, production losses caused by delays in restoring the airflow rate are reduced. Conversely, further ventilation abnormalities caused by restoring the airflow rate too early are reduced.

[0076] While this disclosure has been described based on the drawings and embodiments, it should be noted that those skilled in the art can make various modifications and alterations based on this disclosure. Therefore, it should be noted that these modifications and alterations are within the scope of this disclosure. For example, the functions included in each configuration or step can be rearranged in a logically consistent manner, and multiple configurations or steps can be combined into one or divided.

[0077] For example, the shape, size, pattern, arrangement, orientation, type, and number of each component described above are not limited to those shown in the above description and drawings. The shape, size, pattern, arrangement, orientation, type, and number of each component may be configured arbitrarily as long as they can realize their function. Each component of the illustrated operating apparatus 1 is a functional concept. The specific form of each component is not limited to those shown.

[0078] For example, it is also possible to configure a general-purpose electronic device such as a server, smartphone, or computer to function as the operating device 1 according to the above embodiment. Specifically, a program describing the processing content that realizes each function of the operating device 1 according to the embodiment is stored in the memory of the electronic device, and the processor of the electronic device reads and executes the program. Therefore, this disclosure can also be implemented as a program that can be executed by a processor.

[0079] Alternatively, the disclosure may also be implemented as a non-temporary computer-readable medium storing a program executable by one or more processors for causing an operating device 1, etc., to perform each function according to one embodiment. These should also be understood to be included within the scope of the disclosure.

[0080] In the above embodiment, the determination unit 32 of the control unit 30 decided to increase the airflow when it determined that a predetermined condition including all of the first, second, third, and fourth conditions was met during the determination process, but it is not limited to this. The predetermined condition only needs to include at least the first condition. In addition to the first condition, the predetermined condition may further include at least one of the second, third, and fourth conditions.

[0081] In the above embodiment, the evaluation index for ventilation abnormalities was described as including a Q statistic based on principal component analysis using the output values ​​of the shaft pressure sensors 11 installed around the furnace body of the blast furnace 100 as input, but it is not limited to this. The evaluation index for ventilation abnormalities may include any other index that can evaluate ventilation abnormalities in place of or in addition to the Q statistic.

[0082] In the above embodiment, it was explained that the control unit 30 performs a reduction operation when it determines that the first condition is not met and the Q statistic is on an increasing trend, but this is not limited to this. The control unit 30 does not have to perform a determination process to determine whether or not the Q statistic is on an increasing trend.

[0083] In the above embodiment, it was explained that when the control unit 30 determines that a predetermined condition has been met in the determination process, it restores the airflow rate to the normal state by increasing the airflow rate, but this is not limited to this. The control unit 30 does not have to completely restore the airflow rate to the normal state by increasing the airflow rate, and may restore it to a flow rate different from the airflow rate in the normal state. [Explanation of symbols]

[0084] 1. Operating equipment 10 Sensor section 11. Shaft pressure sensor 12. Top gas thermometer 13. Exhaust gas gauge 20 Memory section 30 Control Unit 31 Arithmetic section 32 Judgment section 40 Output section 100 blast furnace 110 Air vent nozzles 120 Gas purifier C1 Case C2 Case I1 Increased wind pressure instruction I2 Increase wind instruction Th0 Judgment Threshold Th1 First Threshold Th2 Second Threshold Th3 (Third Threshold) Th4 (Fourth Threshold) th5 (5th threshold) Th6 6th threshold Th7 (7th threshold) T fixed time

Claims

1. Operating equipment used in the operation of a blast furnace, It includes a control unit, and the control unit is When a reduced airflow state is detected due to an abnormality in the ventilation of the blast furnace, The Q statistic, which is an evaluation index for ventilation abnormalities based on principal component analysis using the output values ​​of the shaft pressure sensor group installed around the furnace body of the blast furnace as input, The time elapsed since the aforementioned reduced airflow condition occurred, The furnace top temperature of the blast furnace and The gas utilization rate in the aforementioned blast furnace, A determination process for restoring the airflow rate in the reduced airflow state is performed using a determination index that includes at least the following: In the recovery determination process, The second condition, that the aforementioned time is equal to or greater than the second threshold, is determined, and after determining that the second condition is met, The first condition is that the Q statistic is less than or equal to the first threshold, The third condition is that the furnace top temperature is below the third threshold, The fourth condition is that the gas utilization rate is between the fourth threshold and the fifth threshold, If it is determined that the condition is met, the decision is made to increase the airflow. Operating equipment.

2. The operating apparatus according to claim 1, If the control unit determines that the first condition is not met and the Q statistic is on an increasing trend, it will perform a fan reduction operation. Operating equipment.

3. An operating apparatus according to claim 1 or 2, If the control unit determines in the recovery determination process that the first condition, the second condition, the third condition, and the fourth condition have been met, it restores the airflow rate to the normal state by increasing the airflow rate. Operating equipment.

4. An operating apparatus according to claim 1 or 2, A sensor unit used to acquire the aforementioned judgment index, A storage unit that stores data acquired by the sensor unit, Furthermore, The control unit calculates the judgment index by referring to the data stored in the storage unit, and uses the calculated judgment index to determine whether the first condition, second condition, third condition, and fourth condition have been met in the recovery determination process. Operating equipment.

5. A method of operation used in the operation of a blast furnace, When a reduced airflow state is detected due to an abnormality in the ventilation of the blast furnace, The Q statistic, which is an evaluation index for ventilation abnormalities based on principal component analysis using the output values ​​of the shaft pressure sensor group installed around the furnace body of the blast furnace as input, The time elapsed since the aforementioned reduced airflow condition occurred, The furnace top temperature of the blast furnace and The gas utilization rate in the aforementioned blast furnace, The process of determining the return of the airflow rate in the reduced airflow state is performed using a determination index that includes at least the following: In the aforementioned recovery determination process, if it is determined that predetermined conditions are met, the airflow increase operation is decided. Includes, The aforementioned predetermined conditions are: The second condition is that the aforementioned time is equal to or greater than the second threshold, The first condition is that the Q statistic is less than or equal to the first threshold, The third condition is that the furnace top temperature is below the third threshold, The fourth condition is that the gas utilization rate is between the fourth threshold and the fifth threshold, Includes, After it is determined that the second condition is met, the first, third, and fourth conditions are determined. Operating methods.

6. The operating method according to claim 5, The recovery determination process further includes, if it is determined that the first condition is not met and the Q statistic is on an increasing trend, then performing a reduction in airflow operation. Operating methods.

7. The operating method according to claim 5 or 6, If the recovery determination process determines that the first, second, third, and fourth conditions are met, it further includes restoring the airflow rate to the normal state by increasing the airflow rate. Operating methods.

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