Molten iron temperature control method, molten iron temperature control device, molten iron temperature control system, and terminal device

Abstract

The molten iron temperature control method includes: a calculation step (S11-S19) for calculating a pulverized coal ratio operation amount by molten iron temperature control, calculating a pulverized coal flow rate operation amount by pulverized coal ratio tracking control in order to compensate for a deviation between a target value of a pulverized coal ratio taking into account the pulverized coal ratio operation amount and an actual value of the current pulverized coal ratio, and calculating a pulverized coal flow rate operation amount by the pulverized coal flow rate tracking control in order to compensate for the deviation between the target value of the pulverized coal ratio and the actual value of the current pulverized coal ratio; prioritizing the molten iron temperature control or the pulverized coal ratio following control as an optimal action on the basis of the magnitude of the deviation between the target value and the actual value of the pulverized coal ratio; a determination step of determining a basis for calculation relating to the optimal action and adding a statement to a basis statement representing the basis; and a presentation step of presenting operation information including at least one of the pulverized coal ratio operation amount and the pulverized coal flow rate operation amount calculated as the optimal action and the basis statement.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a hot metal temperature control method, a hot metal temperature control device, a hot metal temperature control system, and a terminal device. BACKGROUND

[0002] It is predicted that the labor population will decrease due to the aging of the younger generation, and it is expected that skilled operators who have knowledge and experience in the steel industry will also decrease. Therefore, highly efficient and stable operation based on process automation is pursued.

[0003] A blast furnace is a process in which raw materials such as coke and iron ore are charged from the upper portion of the furnace, hot air and coal powder are blown from tuyeres located at the lower portion of the furnace to melt and reduce the iron ore, and hot metal is obtained from a tap hole. In recent blast furnace operations, a low reduction material ratio and a low coke ratio are targeted in order to reduce CO2 and hot metal costs. On the other hand, high-quality raw materials are being depleted, and thus it is expected that the quality of the raw materials will greatly fluctuate. Therefore, it is predicted that the control of the blast furnace process will become further difficult.

[0004] In achieving highly efficient and stable blast furnace operation, control of the hot metal temperature (HMT) is important. If the hot metal temperature drops extremely, the temperature of the slag, which is a byproduct, drops, causing the viscosity of the slag to rise, and thus discharge from the furnace becomes difficult. Also, if the hot metal or the slag at the lower portion of the furnace solidifies due to insufficient heat, a furnace cold accident occurs, which sometimes leads to a stop in operation. If the target temperature is set high in order to avoid a drop in the hot metal temperature, a large amount of fuel is consumed, leading to an increase in the reduction material ratio. By suppressing the deviation of the hot metal temperature, it is possible to lower the target value while satisfying the lower limit of the hot metal temperature, which contributes to a reduction in the reduction material ratio.

[0005] The hot metal temperature is controlled, for example, by operating the coke ratio, the blast wet fraction, the blast temperature, the coal powder ratio, and the coal powder flow rate. The blast furnace is a process with a large heat capacity, and thus in the case where an operating variable is changed, a time lag of about 2 to 8 hours occurs until the hot metal temperature changes. Therefore, prediction of the hot metal temperature and control based on the prediction, which takes into account the time lag before the effect of the action appears, are required.

[0006] In view of such a background, various hot metal temperature control methods have been proposed. For example, Patent Literature 1 discloses a method in which a control loop of a double structure in which a first control (hot metal temperature control) and a second control (coal powder ratio follow-up control) are executed, and a target value of the coal powder ratio is calculated. In the first control, a target value of the coal powder ratio is calculated so that the hot metal temperature falls within a target range set in advance. In the second control, a coal powder flow rate operation amount is calculated in order to compensate for (reduce) the deviation between the target value of the coal powder ratio and the actual value of the current coal powder ratio.

[0007] Patent Literature 1: Japanese Patent No. 7107444

[0008] The method described in Patent Literature 1 enables control of the molten iron temperature that is not easily affected by variations in the tapping. However, in a case where the molten iron temperature deviates from the target value and the deviation of the target value of the pulverized coal ratio from the actual value of the current pulverized coal ratio is large, there is a concern that an overaction will be performed. Here, the overaction refers to an additional execution of an unnecessary operation. With the method described in Patent Literature 1, although it is sufficient to perform only the operation of the pulverized coal flow rate for compensating the deviation of the pulverized coal ratio (second control), the operation of the pulverized coal ratio (operation based on the first control) can also be performed. In addition, Patent Literature 1 enables automatic control, but there is a tendency that the cases where a reason for the action is shown are less in automatic control. For example, the operator can be made to have a sense of acceptance by the basis of the operation amount prompt calculation for the operation variable. SUMMARY

[0009] The present disclosure accomplished in view of the circumstances aims to provide a molten iron temperature control method, a molten iron temperature control device, a molten iron temperature control system, and a terminal device that can suppress an overaction and show a best action and a basis of calculation.

[0010] (1) A molten iron temperature control method according to one embodiment of the present disclosure includes:

[0011] a calculation step of calculating a pulverized coal ratio operation amount by a molten iron temperature control so that a molten iron temperature predicted by a physical model capable of calculating a state in a blast furnace falls within a target range set in advance, calculating a pulverized coal flow rate operation amount by a pulverized coal ratio follow-up control in order to compensate for a deviation of a target value of the pulverized coal ratio considering the pulverized coal ratio operation amount from an actual value of the current pulverized coal ratio, and giving priority to the molten iron temperature control or the pulverized coal ratio follow-up control as a best action based on a size of a deviation of the target value of the pulverized coal ratio from the actual value;

[0012] a determination step of determining a basis of calculation related to the best action and adding a sentence of a basis sentence indicating the basis; and

[0013] a prompt step of prompting operation information including at least one of the pulverized coal ratio operation amount and the pulverized coal flow rate operation amount calculated as the best action and the basis sentence.

[0014] (2) As one embodiment of the present disclosure, on the basis of (1),

[0015] in a case where an absolute value of the pulverized coal flow rate operation amount is larger than an operation range of the pulverized coal flow rate that can be changed each time, the calculation step gives priority to the pulverized coal ratio follow-up control and does not take the pulverized coal operation amount calculated by the molten iron temperature control into the target value of the pulverized coal ratio.

[0016] (3) As one embodiment of the present disclosure, on the basis of (1) or (2),

[0017] In a case where the molten iron temperature prediction value calculated in consideration of the pulverized coal flow operation amount deviates from the target range of the molten iron temperature, the calculation step prioritizes the molten iron temperature control, and the pulverized coal operation amount calculated by the molten iron temperature control is considered in the target value of the pulverized coal ratio.

[0018] (4) As one embodiment of the present disclosure, on the basis of any one of (1) to (3),

[0019] The determination step appends a plurality of sentences to the basis sentence,

[0020] The plurality of sentences include a plurality of change contents arranged in order from near to far from the current time or in order from large to small in the amount of change.

[0021] (5) As one embodiment of the present disclosure, on the basis of any one of (1) to (4),

[0022] The operation information is an operation amount prompt screen having a sentence indicating the intention of the optimal action, a basis for calculation of the optimal action, an agree button, and a do not adopt button,

[0023] The agree button is used in a case where the operator agrees to the optimal action shown in the operation amount prompt screen,

[0024] The do not adopt button is used in a case where the operator does not adopt the optimal action shown in the operation amount prompt screen.

[0025] (6) As one embodiment of the present disclosure, on the basis of (5),

[0026] The prompting step has a semi-automatic mode in which the optimal action is executed with the approval of the operator and an automatic mode in which the optimal action is executed even without the approval of the operator as a control mode,

[0027] In a case where the control mode is the automatic mode, the operation information is an operation amount prompt screen further having a timer,

[0028] The timer displays a time from a time at which display related to the optimal action is updated to a predetermined prescribed time, and the optimal action is executed in a case where the do not adopt button is not selected before the prescribed time.

[0029] (7) A molten iron temperature control device according to one embodiment of the present disclosure includes:

[0030] The computing section calculates a pulverized coal ratio operation amount so that a molten iron temperature predicted by a physical model capable of calculating a state in the blast furnace falls within a target range set in advance, calculates a pulverized coal flow operation amount by a pulverized coal ratio follow-up control in order to compensate for a deviation of a target value of the pulverized coal ratio considering the pulverized coal ratio operation amount from a current actual value of the pulverized coal ratio, and prioritizes the molten iron temperature control or the pulverized coal ratio follow-up control as an optimal action based on a size of a deviation of the target value of the pulverized coal ratio from the actual value;

[0031] The determining section determines a basis for the calculation related to the optimal action and appends a statement to a statement indicating the basis; and

[0032] The prompting section prompts operation information including at least one of the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action and the statement of the basis.

[0033] (8) As one embodiment of the present disclosure, on the basis of (7),

[0034] In a case where an absolute value of the pulverized coal flow operation amount is greater than an operation range of the pulverized coal flow that can be changed each time, the computing section prioritizes the pulverized coal ratio follow-up control and does not consider the pulverized coal operation amount calculated by the molten iron temperature control in the target value of the pulverized coal ratio.

[0035] (9) As one embodiment of the present disclosure, on the basis of (7) or (8),

[0036] In a case where a molten iron temperature prediction value calculated considering the pulverized coal flow operation amount deviates from the target range of the molten iron temperature, the computing section prioritizes the molten iron temperature control and considers the pulverized coal operation amount calculated by the molten iron temperature control in the target value of the pulverized coal ratio.

[0037] (10) As one embodiment of the present disclosure, on the basis of any one of (7) to (9),

[0038] The determining section appends a plurality of statements to the statement of the basis,

[0039] The plurality of statements include a plurality of change contents arranged in order from near to far from a current time or in order from large to small in a change amount.

[0040] (11) As one embodiment of the present disclosure, on the basis of any one of (7) to (10),

[0041] The operation information is an operation amount prompt screen having a sentence indicating the intention of the above-mentioned optimal action, a basis for calculation of the above-mentioned optimal action, an agreement button, and a non-adopt button,

[0042] The agreement button is used when the operator agrees to the above-mentioned optimal action shown in the operation amount prompt screen,

[0043] The non-adopt button is used when the operator does not adopt the above-mentioned optimal action shown in the operation amount prompt screen.

[0044] (12) As one embodiment of the present disclosure, on the basis of (11),

[0045] The prompt unit has a semi-automatic mode in which the optimal action is executed with the approval of the operator and an automatic mode in which the optimal action is executed even without the approval of the operator as a control mode,

[0046] In the case where the control mode is the automatic mode, the operation information is an operation amount prompt screen further having a timer,

[0047] The timer displays the time from the time when the display related to the above-mentioned optimal action is updated to a predetermined prescribed time, and in the case where the non-adopt button is not selected before the prescribed time, the above-mentioned optimal action is executed.

[0048] (13) An iron temperature control system according to one embodiment of the present disclosure includes an iron temperature control device and a terminal device, wherein:

[0049] A calculation unit calculates a pulverized coal ratio operation amount so that an iron temperature predicted by a physical model capable of calculating a state in a blast furnace falls within a target range set in advance, and calculates a pulverized coal flow operation amount by pulverized coal ratio follow-up control in order to compensate for a deviation between a target value of the pulverized coal ratio considering the above-mentioned pulverized coal ratio operation amount and an actual value of the above-mentioned pulverized coal ratio, and gives priority to the above-mentioned iron temperature control or the above-mentioned pulverized coal ratio follow-up control as an optimal action based on the magnitude of the deviation between the target value and the actual value of the above-mentioned pulverized coal ratio;

[0050] A determination unit determines a basis for calculation related to the above-mentioned optimal action, and adds a basis sentence indicating the above-mentioned basis;

[0051] An output unit outputs operation information including at least one of the above-mentioned pulverized coal ratio operation amount and the above-mentioned pulverized coal flow operation amount calculated as the above-mentioned optimal action and the above-mentioned basis sentence;

[0052] A communication unit performs transmission and reception of the above-mentioned operation information;

[0053] an acquisition unit that acquires the optimal action and the operation information related to the optimal action including the basis sentence;

[0054] a display unit that displays the acquired optimal action and operation information including the basis sentence; and

[0055] an interface unit that receives an instruction with respect to the displayed operation information and outputs a set value of an operation variable according to the instruction or based on a lapse of a predetermined time.

[0056] (14) A terminal device according to an embodiment of the present disclosure, together with a molten iron temperature control device, constitutes a molten iron temperature control system, and in order to control a molten iron temperature, the molten iron temperature control device outputs operation information including at least one of a pulverized coal ratio operation amount and a pulverized coal flow operation amount calculated as an optimal action and a basis sentence indicating a basis of the calculation related to the optimal action, based on a size of a deviation of a target value of a pulverized coal ratio from an actual value of the pulverized coal ratio, wherein the terminal device includes:

[0057] an acquisition unit that acquires the optimal action and the operation information related to the optimal action including the basis sentence;

[0058] a display unit that displays the acquired optimal action and operation information including the basis sentence; and

[0059] an interface unit that receives an instruction with respect to the displayed operation information and outputs a set value of an operation variable according to the instruction or based on a lapse of a predetermined time.

[0060] (15) As an embodiment of the present disclosure, in (14),

[0061] the operation information includes a plurality of operation conditions, and is displayed together with a priority order.

[0062] According to the present disclosure, it is possible to provide a molten iron temperature control method, a molten iron temperature control device, a molten iron temperature control system, and a terminal device that can suppress excessive action and show an optimal action and a basis of the calculation. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 is a block diagram showing a configuration example of a molten iron temperature control device according to an embodiment of the present disclosure.

[0064] Figure 2 is a flowchart illustrating a process of a calculation unit.

[0065] Figure 3 is a flowchart illustrating a process of a determination unit.

[0066] Figure 4is a flowchart illustrating the process of the prompt section.

[0067] Figure 5 is a view illustrating an operation amount prompt screen in a case where the control mode is the automatic mode.

[0068] Figure 6 is a view illustrating an operation amount prompt screen in a case where the control mode is the semi-automatic mode.

[0069] Figure 7 is a view illustrating another operation amount prompt screen in a case where the control mode is the automatic mode.

[0070] Figure 8 is a view illustrating one example of changes in the target value of the molten iron temperature, the target value of the pulverized coal ratio, and the set value of the pulverized coal flow rate for the current time, the past 8 hours, and the future 10 hours.

[0071] Figure 9 is a view illustrating another example of changes in the target value of the molten iron temperature, the target value of the pulverized coal ratio, and the set value of the pulverized coal flow rate for the current time, the past 8 hours, and the future 10 hours.

[0072] Figure 10 is a view illustrating one example of changes in the molten iron temperature, the coke ratio, the pulverized coal ratio operation amount, the pulverized coal ratio, the pulverized coal flow rate operation amount, the pulverized coal flow rate, the blast flow rate, and the pig iron production rate for 60 hours.

[0073] Figure 11 is a view illustrating an example of changes in the molten iron temperature, the coke ratio, the pulverized coal ratio, the pulverized coal flow rate, the blast flow rate, the pig iron production rate, and the inferior raw material charging ratio for 60 hours.

[0074] Figure 12 is a block diagram illustrating a configuration example of a molten iron temperature control system provided with a molten iron temperature control device. DETAILED DESCRIPTION

[0075] Hereinafter, a molten iron temperature control method, a molten iron temperature control device, a molten iron temperature control system, and a terminal device according to one embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or equivalent parts are denoted by the same reference numerals. In the description of the present embodiment, the description of the same or equivalent parts will be appropriately omitted or simplified.

[0076] [Structure of Molten Iron Temperature Control Device]

[0077] Figure 1 is a block diagram illustrating the structure of a molten iron temperature control device 1 according to one embodiment of the present disclosure. As illustrated in the block diagram, the molten iron temperature control device 1 includes a molten iron temperature control system 10, a terminal device 20, and a server 30. Figure 1As illustrated, the molten iron temperature control device 1 according to the present embodiment can be constituted by an information processing device such as a computer. Specifically, an internal arithmetic processing device such as a CPU (Central Processing Unit) executes a program, whereby the computer or the like functions as the molten iron temperature control device 1.

[0078] The operation database 2 is connected to the molten iron temperature control device 1 in a data readable manner. In the present embodiment, the operation database 2 stores operation factors, calculated values of process variables, actual values of process variables, and historical data of temperatures or pressures measured at the furnace body, the top, or the bottom. The operation factors are, for example, the top coke ratio, the blast flow rate, the oxygen enrichment amount, the blast temperature, the blast humidity, the pulverized coal ratio, and the pulverized coal flow rate. The calculated values of process variables are, for example, the gas utilization rate, the dissolved loss carbon, the molten iron temperature, and the iron-making speed, which are output from the physical model. The actual values of process variables are, for example, calculated based on the volume fraction of CO or CO2 of the discharged top gas. The process variables can be, for example, the iron-making speed, the molten iron temperature, the dissolved loss carbon, and the gas utilization rate. The operation database 2 successively saves and stores the measured data required for operation and the operation factors required for the molten iron temperature control, and these pieces of information are read and used as needed. In addition, the calculated values of process variables output from the physical model are successively saved in the operation database 2 each time the molten iron temperature control device 1 calculates.

[0079] The physical model used in the present disclosure is the same model as the method described in the reference (HATANO Haru et al.: "Study on Start-up Operation Based on Non-steady-state Model of Blast Furnace", Iron and Steel, vol. 68, p. 2369). That is, the physical model is constituted by a system of partial differential equations that takes into account multiple physical phenomena such as the reduction of iron ore, heat exchange between iron ore and coke, and melting of iron ore, and is a physical model that can calculate variables (output variables) that represent the state in the blast furnace in a non-steady state.

[0080] The molten iron temperature control device 1 according to the present embodiment is provided with a calculation section 11, a determination section 12, and a presentation section 13. The molten iron temperature control device 1 can control the molten iron temperature by the calculation section 11, the determination section 12, and the presentation section 13 executing the processes described below. In addition, the molten iron temperature control device 1 can be provided with a storage device, in which case the storage device can store the physical model. The molten iron temperature control device 1 can read out the physical model from the storage device to use in the calculation in the case of executing the processes described below.

[0081] [Action of the calculation section]

[0082] Reference Figure 2 The action of the calculation section 11 will be described. Figure 2 At least a part of the processes illustrated corresponds to the calculation step executed by the calculation section 11.

[0083] Figure 2 is a flowchart showing a processing flow of the calculation section 11. Figure 2 The flowchart shown in the figure becomes started at the timing when the execution instruction is input to the calculation section 11, and proceeds to the processing of step Sll.

[0084] In the processing of step Sll, the calculation section 11 calculates the pulverized coal ratio operation amount ΔPCR0 so that the molten iron temperature predicted by the physical model falls within the target range set in advance. In the present embodiment, the method of calculation of step Sll is the same as the method of molten iron temperature control described in the above-mentioned Patent Document 1. That is, ΔPCR0 and the following ΔPCI0 are calculated by the molten iron temperature control.

[0085] In the calculation of the operation amount of the pulverized coal ratio (PCR), that is, the pulverized coal ratio operation amount (ΔPCR), the so-called speed type method in which the amount of change is added or subtracted with respect to the operation amount is used. Therefore, the adjusted pulverized coal ratio is set by adding ΔPCR to the target value (PCR ref (0)) of the current pulverized coal ratio.

[0086] Next, using the current iron production rate Prod(0), the moderation coefficient α0 (0 < α0 ≤ 1), the pulverized coal flow operation amount ΔPCI0 corresponding to the pulverized coal ratio operation amount ΔPCR0 is calculated in accordance with equation (1). The pulverized coal flow operation amount (ΔPCI) is the operation amount of the pulverized coal flow (PCI). The suffix 0 indicates correspondence to ΔPCR0. As for the pulverized coal flow, the pulverized coal flow operation amount ΔPCI0 is also calculated as an addition or subtraction with respect to the value of the current PCI. The processing of the calculation section 11 proceeds to the processing of step S12.

[0087] [Equation 1]

[0088] ΔPCI0 = α0 · ΔPCR0 · Prod(0) (1)

[0089] In the processing of step S12, in order to compensate for the deviation of the target value of the pulverized coal ratio from the current value (actual value of the current pulverized coal ratio), the calculation section 11 calculates the pulverized coal flow operation amount. In the present embodiment, the method of calculation of step S12 is the same as the method of pulverized coal ratio follow-up control described in the above-mentioned Patent Document 1. That is, the following ΔPCR1 is calculated by the pulverized coal ratio follow-up control. First, the current pulverized coal flow is set to PCI(0), the target value of the pulverized coal ratio is set to PCR ref (0), and the deviation δPCR of the target value from the actual value of the pulverized coal ratio is calculated in accordance with equation (2).

[0090] [Equation 2]

[0091]

[0092] Next, the pulverized coal flow operation amount ΔPCI1 for compensating for the deviation δPCR of the target value from the actual value of the pulverized coal ratio is calculated using the alleviation coefficient α1 (0 < α1 ≤ 1) according to (3). The processing of the calculation section 11 proceeds to the processing of Step S13.

[0093] [Equation 3]

[0094] ΔPCI1 = -α1 · δPCR · Prod(0) (3)

[0095] In the processing of Step S13, the calculation section 11 determines whether the absolute value |ΔPCI1| of the pulverized coal flow operation amount for compensating for the deviation δPCR of the target value from the actual value of the pulverized coal ratio is greater than the operation amplitude A of the pulverized coal flow that can be changed each time. |ΔPCI1| being greater than the operation amplitude A means that the actual value of the pulverized coal ratio deviates greatly from the target value of the current pulverized coal ratio. Here, in the method described in the above-described Patent Document 1, there is a concern that excessive action is taken in a case where the molten iron temperature deviates from the target value and the actual value of the pulverized coal ratio deviates greatly from the target value of the current pulverized coal ratio. In the present embodiment, in the case where the deviation is great, the increase / decrease amount of the pulverized coal ratio operation amount based on the molten iron temperature control, that is, the addition operation to the target value of the pulverized coal ratio is not considered in principle, and only the operation of the pulverized coal flow for the purpose of following the target value of the pulverized coal ratio at that time is taken as the best action. In the case where the deviation is great, excessive action can be suppressed by not considering the pulverized coal operation amount calculated by the molten iron temperature control in (reflecting to) the target value of the pulverized coal ratio. That is, in the present embodiment, in the case where the deviation is great, the pulverized coal ratio following control is given priority in principle, and only the operation of the pulverized coal flow is performed for compensating for the deviation of the pulverized coal ratio, whereby a decrease in the precision of the molten iron temperature control due to excessive operation of the pulverized coal ratio can be prevented. In the case where |ΔPCI1| is greater than the operation amplitude A (Yes in Step S13), the calculation section 11 proceeds to the processing of Step S14. In the case where |ΔPCI1| is equal to or less than the operation amplitude A (No in Step S13), the calculation section 11 proceeds to the processing of Step S19.

[0096] In the processing of Step S14, the calculation section 11 calculates the molten iron temperature prediction value taking into account the pulverized coal flow operation amount ΔPCI1. The step response S PCI (k|t0) of the molten iron temperature in the case where the unit amount of the pulverized coal flow at the current time t0 is changed, and the free response y free (t0+k) of the molten iron temperature in the case where the current input variable is assumed to be maintained in the future is calculated using the physical model. The molten iron temperature prediction value y pre(t0+k). The calculation section 11 proceeds to the process of step S15.

[0097] [Formula 4]

[0098] y pre (t0+k) = S PCI (k|t0) · ΔPCI1 + y free (t0+k) (4)

[0099] In the process of step S15, the calculation section 11 determines whether the molten iron temperature prediction value y pre (t0+k) is within the target range of the molten iron temperature. In the case where the process of step S15 is performed, although it is a state where the deviation of the target value and the actual value of the pulverized coal ratio is large, if the pulverized coal ratio follow-up control is prioritized, there is a concern that the molten iron temperature will remain deviated from the target, either to the low side or to the high side (i.e., deviated from within the target range of the molten iron temperature). In this case, the molten iron temperature control can be prioritized, and the operation of the pulverized coal ratio is also performed. In the case where the molten iron temperature prediction value y pre (t0+k) is within the target range of the molten iron temperature (YES of step S15), the calculation section 11 proceeds to the process of step S16. Also, in the case where the molten iron temperature prediction value y pre (t0+k) is not within the target range of the molten iron temperature (NO of step S15), the calculation section 11 proceeds to the process of step S18. The calculation section 11 prioritizes the molten iron temperature control or the pulverized coal ratio follow-up control as the best action, based on the magnitude of the deviation of the target value and the actual value of the pulverized coal ratio.

[0100] In the process of step S16, the calculation section 11 sets the "pulverized coal ratio follow-up control priority flag" to true. The calculation section 11 proceeds to the process of step S17.

[0101] In the process of step S17, the calculation section 11 does not take ΔPCI0 into account in the final- instructed pulverized coal ratio operation amount ΔPCR, but takes the final- instructed pulverized coal flow operation amount ΔPCI as ΔPCI1, and ends the series of processes.

[0102] In the process of step S18, the calculation section 11 sets the "molten iron temperature control priority flag" to true. The calculation section 11 proceeds to the process of step S19.

[0103] In the process of step S19, the calculation section 11 takes the final- instructed pulverized coal ratio operation amount ΔPCR as ΔPCR0, and takes the final- instructed pulverized coal flow operation amount ΔPCI as the sum of ΔPCI0 and ΔPCI1 (the value obtained by adding ΔPCI1 to ΔPCI0), and ends the series of processes.

[0104] [Action of determination section]

[0105] Referring toFigure 3 The operation of the determination section 12 will be described. Figure 3 At least a part of the processing shown corresponds to the determination step performed by the determination section 12. The determination section 12 determines the basis of the calculation related to the optimal action, and appends a basis sentence to the sentence indicating the basis. A specific example of the appended sentence will be described later.

[0106] Figure 3 is a flowchart showing the processing flow of the determination section 12. Figure 3 The flowchart shown becomes the start at the timing when the execution instruction is input to the determination section 12, and proceeds to the determination of step S21.

[0107] In the processing of step S21, the determination section 12 determines whether the coal ratio follow-up control priority flag is established in the calculation section 11. If the coal ratio follow-up control priority flag is established, the determination section 12 proceeds to the processing of step S22. If the coal ratio follow-up control priority flag is not established, the determination section 12 proceeds to the processing of step S23.

[0108] In the processing of step S22, the determination section 12 appends "coal ratio follow-up control priority" to the basis sentence. The basis sentence indicates the reason for the operation (action) in progress, and becomes the content displayed in the "optimal action prompting basis 32" described later. The basis sentence can be stored in the storage device provided in the molten iron temperature control device 1. Thereby, the determination section 12 proceeds to the processing of step S25.

[0109] In the processing of step S23, the determination section 12 determines whether the molten iron temperature control priority flag is established in the calculation section 11. If the molten iron temperature control priority flag is established, the determination section 12 proceeds to the processing of step S24. If the molten iron temperature control priority flag is not established, the determination section 12 proceeds to the processing of step S25.

[0110] In the processing of step S24, the determination section 12 appends "molten iron temperature control priority" to the basis sentence. Thereby, the determination section 12 proceeds to the processing of step S25.

[0111] In the processing of step S25, the determination section 12 determines whether there is a contradiction with the operation constraint that should temporarily suspend the action of the coal ratio or the coal flow rate.

[0112] For example, in a case where the pulverized coal ratio is excessively large, it is possible to cause deterioration of the blow. Therefore, there can be an upper limit of the pulverized coal ratio as an operation constraint. In a case where the current pulverized coal ratio exceeds the upper limit, the determination section 12 appends "pulverized coal ratio upper limit" to the basis sentence. Further, for example, in a case where the reducing material ratio is extremely small, it is possible to cause a sharp drop in the molten iron temperature and deterioration of the blow. Therefore, there can be a lower limit of the reducing material ratio as an operation constraint. In a case where the current reducing material ratio is lower than the lower limit, the determination section 12 appends "reducing material ratio lower limit" to the basis sentence. Further, for example, in a case where the top gas temperature is low, it is possible to cause damage to the blast furnace equipment due to generation of coal ash or condensation of moisture in the top gas at the top of the furnace. Therefore, there can be a lower limit of the top gas temperature as an operation constraint. In a case where the current top gas temperature is lower than the lower limit, the determination section 12 appends "top gas temperature lower limit" to the basis sentence. Further, for example, in a case where the theoretical combustion temperature at the tuyere front end is excessively low, it is possible that the pulverized coal does not burn at the tuyere. On the other hand, in a case where the theoretical combustion temperature is excessively high, it is possible to damage the tuyere. Therefore, there can be upper and lower limits of the theoretical combustion temperature as operation constraints. In a case where the current theoretical combustion temperature is not within the range of the upper and lower limits, the determination section 12 appends "theoretical combustion temperature upper limit" or "theoretical combustion temperature lower limit" to the basis sentence.

[0113] In a case where there is a contradiction with the above-described operation constraint, the determination section 12 proceeds to the processing of step S26. In a case where there is no contradiction with the operation constraint, the determination section 12 proceeds to the processing of step S27.

[0114] In the processing of step S26, as described above, the determination section 12 appends, for example, "pulverized coal ratio upper limit", "reducing material ratio lower limit", "top gas temperature lower limit", "theoretical combustion temperature upper limit", or "theoretical combustion temperature lower limit" or the like to the basis sentence. Thereby, the determination section 12 proceeds to the processing of step S27.

[0115] In the processing of Step S27, the determination section 12 determines whether there is a change in the operation variable or the index based on the progress of the operation variable related to the molten iron temperature control and the index having a high correlation with the molten iron temperature. As the operation variable, the coke ratio, the pulverized coal ratio, the blast temperature, and the blast humidity can be cited. In addition, as the index having a high correlation with the molten iron temperature, the tuyere buried temperature, the components of silicon and sulfur in the molten iron, the theoretical combustion temperature, and the dissolved loss carbon can be cited. As to the presence or absence of the change, the determination section 12 can calculate the difference from the value at the current time, and determine based on the case where the absolute value of the difference exceeds a threshold value. In addition, the determination section 12 can determine the change in the index using a machine learning model that takes a progress graph as input. In the case where a plurality of items have changed, the determination section 12 can arrange the corresponding plurality of sentences in order from near to far from the current time or in order from large to small in the amount of change. In the case where there is a change in the operation variable or the index, the determination section 12 proceeds to the processing of Step S28. In the case where there is no change in the operation variable and the index, the determination section 12 ends the series of processing.

[0116] In the processing of Step S28, the determination section 12, for example, adds the operation variable or the index that has changed, the time at which the change has occurred (as one example, several hours before the current time), and the direction of the change (for example, increase or decrease) and the like to the basis sentence in correspondence, thereby adding a sentence. Thus, the determination section 12 ends the series of processing. In this way, the determination section 12 adds a sentence to the basis sentence indicating the basis of the calculation related to the optimal action described above.

[0117] Here, as described above, the basis sentence can include a plurality of operation constraints and change contents. However, in order not to make the information excessive, it is preferable that the number of operation constraints and change contents included in the basis sentence be one to four.

[0118] [Action of the prompting section]

[0119] Reference Figure 4 The action of the prompting section 13 will be described. The prompting section 13 prompts the operator with operation information. Figure 4 At least a part of the processing illustrated in the flowchart corresponds to a prompting step performed by the prompting section 13.

[0120] Figure 4 is a flowchart indicating the processing flow of the prompting section 13. Figure 4 The flowchart illustrated in the figure becomes the start at the timing when the execution instruction is input to the prompting section 13, and proceeds to the processing of Step S31.

[0121] In the processing of step S31, the prompting section 13 determines whether the absolute value of the operation amount of the optimum action obtained by the calculating section 11 exceeds the minimum unit of change that can be set, thereby determining the necessity of execution. For example, in the case where the target value of the coal ratio is changed by the minimum unit of 2 kg / t, even if the coal ratio operation amount is calculated by the calculating section 11 as +1 kg / t, it is determined that action is not necessary. By the processing of step S31, the over-frequent prompting can be suppressed. In addition, the over-frequent prompting is suppressed, which contributes to preventing fluctuations in the molten iron temperature. When it is determined in step S31 that action is necessary, the processing of the prompting section 13 proceeds to the processing of step S32. When it is determined in step S31 that action is not necessary, the processing of the prompting section 13 ends the series of processing.

[0122] In the processing of step S32, the prompting section 13 determines whether τ1 minutes have elapsed since the last execution of action. τ1 is nonzero, but is not limited to a particular value. When τ1 minutes have elapsed since the last execution of action, the processing of the prompting section 13 proceeds to the processing of step S33. When τ1 minutes have not elapsed since the last execution of action, the processing of the prompting section 13 ends the series of processing. The blast furnace is a process with a long time constant, and thus it takes time until the effect of action is found. Therefore, it is possible that the same action is implemented soon after the most recent operation, becoming over-action. In order to suppress over-action, the processing of step S32 is important. Here, it is preferable that τ1 include a plurality of values to be selected. It is preferable that τ1 be set to different values in the case where the blast air flow rate, the oxygen enrichment amount, or the coke ratio has been recently changed greatly, and the like, and in ordinary times.

[0123] In the processing of step S33, the prompting section 13 determines whether the difference between the set value of the operation variable (for example, the blast air flow rate, the oxygen enrichment amount, or the coke ratio, and the like) used in the processing of step S32 and the set value of the operation variable set at the current time is within a threshold value. If it is within the threshold value, the processing of the prompting section 13 proceeds to the processing of step S34. In the case where it is greater than the threshold value, the processing of the prompting section 13 ends the series of processing. When the set value has been greatly changed by the operator for some reason such as equipment failure or poor furnace conditions during the series of processing, the operation amount obtained by the processing of the calculating section 11 is not the recommended action, and it is possible that the controllability of the molten iron temperature deteriorates due to execution. By the processing of step S33, it is possible to prevent the loss of control of the molten iron temperature control device 1 due to external disturbance.

[0124] In the processing of step S34, the prompting section 13 judges the set control mode. In the present embodiment, the prompting section 13 has two modes as the control mode. That is, the prompting section 13 can use a semi-automatic mode in which the optimal action is executed with the approval of the operator or an automatic mode in which the optimal action is executed even without the approval of the operator. In the case where the control mode is the automatic mode, the processing of the prompting section 13 proceeds to the processing of step S35. In the case where the control mode is the semi-automatic mode, the processing of the prompting section 13 proceeds to the processing of step S36.

[0125] In the processing of step S35, the information based on the optimal action shown in FIG. 9 is displayed in a pop-up window on the operation terminal of the operator, and an alarm is issued. In the case where the control mode is the automatic mode, a timer 36 until the action execution is set on the screen. At the moment of the pop-up window display, that is, at the time when the display related to the optimal action is updated, the timer 36 is set for τ2 seconds, and the countdown is started. If the operator presses the non-acceptance button 35 before the timer 36 becomes 0 seconds, the pop-up window is eliminated, and the processing of the prompting section 13 ends the series of processing. In the case where the operator does not press (does not select) the non-acceptance button 35 or the operator presses (selects) the acceptance button 34 before the timer 36 becomes 0 seconds, the processing of the prompting section 13 proceeds to the processing of step S37. That is, in the case where the operator does not reject within τ2 seconds, the optimal action is executed. In order to notice the automatic execution of the action, an alarm can be issued at a timing of τ3 that satisfies 0 < τ3 < τ2. τ2 and τ3 are non-zero, but are not limited to specific values. Here, "0 seconds" is one example of the predetermined prescribed time, and other values can be used. The timer 36 is not limited to a countdown timer, but can be a timer that displays the time until the predetermined prescribed time. Figure 5 In the processing of step S36, the information based on the optimal action shown in FIG. 10 is displayed in a pop-up window on the operation terminal of the operator, and an alarm is issued. In the case where the control mode is the semi-automatic mode, the timer 36 until the action execution is not set on the screen. The execution of the action requires the approval of the operator. In the case where the operator presses the acceptance button 44, the processing of the prompting section 13 proceeds to the processing of step S37. In the case where the operator presses the non-acceptance button 45, the pop-up window is eliminated, and the processing of the prompting section 13 ends the series of processing. In order not to leave the pop-up window as it is and be ignored by the operator, an alarm can be issued every τ4 minutes from the moment of the pop-up window display in the case where neither the acceptance button 44 nor the non-acceptance button 45 is pressed. τ4 is non-zero, but is not limited to a specific value.

[0126] Figure 6 In the processing of step S36, the information based on the optimal action shown in FIG. 10 is displayed in a pop-up window on the operation terminal of the operator, and an alarm is issued. In the case where the control mode is the semi-automatic mode, the timer 36 until the action execution is not set on the screen. The execution of the action requires the approval of the operator. In the case where the operator presses the acceptance button 44, the processing of the prompting section 13 proceeds to the processing of step S37. In the case where the operator presses the non-acceptance button 45, the pop-up window is eliminated, and the processing of the prompting section 13 ends the series of processing. In order not to leave the pop-up window as it is and be ignored by the operator, an alarm can be issued every τ4 minutes from the moment of the pop-up window display in the case where neither the acceptance button 44 nor the non-acceptance button 45 is pressed. τ4 is non-zero, but is not limited to a specific value.

[0127] ​In the processing of step S37, the pop-up window displayed in step S35 or step S36 disappears, and the set value of the operation variable is overwritten (updated) with the value calculated based on the optimal action. Thus, the processing of step S37 is completed, and the prompting section 13 ends the series of processing. The set value of the operation variable after the overwriting (updating) is output to a computer or the like of the control operation device 4 (refer to Figure 12 ), for example, and is reflected in the operation device 4.

[0128] [Operation Amount Prompting Screen]

[0129] Figure 5 is a view showing an operation amount prompting screen in the case where the control mode of the molten iron temperature control device 1 is the automatic mode.

[0130] The operation amount prompting screen shows a sentence 31 indicating the intention of the optimal action (for example, molten iron temperature rise, molten iron temperature drop, or pulverized coal ratio control, etc.), and a prompting basis 32 of the optimal action decided by the decision section 12. In addition, the operation amount prompting screen shows an optimal operation amount 33, an agree button 34, a do not adopt button 35, and a timer 36. The optimal operation amount 33 shows at least one of the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action.

[0131] Figure 6 is a view showing an operation amount prompting screen in the case where the control mode of the molten iron temperature control device 1 is the semi-automatic mode.

[0132] The operation amount prompting screen shows a sentence 41 indicating the direction of the optimal action (for example, molten iron temperature rise, molten iron temperature drop, or pulverized coal ratio control, etc.), and a prompting basis 42 of the optimal action decided by the decision section 12. In addition, the operation amount prompting screen shows an optimal operation amount 43, an agree button 44, and a do not adopt button 45. The optimal operation amount 43 shows at least one of the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action.

[0133] Figure 7 is a view showing another operation amount prompting screen in the case where the control mode of the molten iron temperature control device 1 is the automatic mode. In Figure 7 , the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action are prompted, and as the other action, two cases using other operation amounts calculated based on the physical model of the molten iron temperature control (in the example of Figure 7 , the blast wetness) are prompted. In the example of Figure 7 , the operation information includes a plurality of operation conditions, and is displayed together with the priority order (1 to 3 of Figure 7 ). Here, due to the constraints of the operation, there can be operation amounts that cannot be performed. Therefore, as in Figure 7Examples, a plurality of recommended actions are preferably prompted to allow the operator to select the operation. In addition, to prevent button pressing errors, a specification can be adopted in which the "execute" button is further pressed after the "agree" or "do not adopt" button is pressed.

[0134] [Example 1]

[0135] In this example, Figure 8 A case in which the molten iron temperature control priority flag is established by the processing of the calculation section 11 is shown in FIG. 6. Figure 8 is a graph showing changes in the target value of the molten iron temperature (HMT) and the set value of the pulverized coal flow (PCI) for the past 8 hours and the future 10 hours with the current time set to 0. The dashed line of the molten iron temperature is the upper and lower limits of the target value. The thick solid line of the past 8 hours is the actual performance value. The thin solid line is the calculated value of the physical model including the future prediction. The dashed line is the predicted value of the molten iron temperature in the case in which the calculated action is implemented. The triangular mark of the pulverized coal ratio indicates the actual performance value of the pulverized coal ratio at the current time. In addition, the arrows in the pulverized coal ratio and the pulverized coal flow indicate the action calculated in the calculation section 11. In this example, the deviation of the target value from the actual performance value of the pulverized coal ratio is large, and on the other hand, if the pulverized coal ratio is made to follow the control priority, the rise in the molten iron temperature cannot be suppressed. Therefore, the action of the pulverized coal ratio and the pulverized coal flow is prompted with the molten iron temperature control priority.

[0136] [Example 2]

[0137] In this example, Figure 9 A case in which the pulverized coal ratio follow-up control priority flag is established by the processing of the calculation section 11 is shown in FIG. 7. Figure 9 is a graph showing changes in the target value of the molten iron temperature (HMT) and the set value of the pulverized coal flow (PCI) for the past 8 hours and the future 10 hours with the current time set to 0. The dashed line of the molten iron temperature is the upper and lower limits of the target value. The thick solid line of the past 8 hours is the actual performance value. The thin solid line is the calculated value of the physical model including the future prediction. The dashed line is the predicted value of the molten iron temperature in the case in which the calculated action is implemented. The triangular mark of the pulverized coal ratio indicates the actual performance value of the pulverized coal ratio at the current time. In addition, the arrows in the pulverized coal ratio and the pulverized coal flow indicate the action calculated in the calculation section 11. In this example, the deviation of the target value from the actual performance value of the pulverized coal ratio is large, and on the other hand, if the pulverized coal ratio is made to follow the control priority, the rise in the molten iron temperature cannot be suppressed. Therefore, the action of the pulverized coal ratio and the pulverized coal flow is prompted with the molten iron temperature control priority. Figure 8 [Example 3]

[0138] In this example, the semi-automatic mode is used as the control mode of the molten iron temperature control device 1, and the operation is implemented by operating the pulverized coal ratio and the pulverized coal flow. τ1 is 40 [minutes].

[0139]

[0140] is a graph showing changes in the molten iron temperature, the coke ratio, the pulverized coal ratio operation amount, the pulverized coal ratio, the pulverized coal flow operation amount, the pulverized coal flow, the blast flow, and the iron production rate for 60 hours. Figure 10 In

[0141] Figure 10 ​The solid line is the actual value. The dotted line indicates the target value. Figure 10 The circle of the pulverized coal ratio operation amount and the pulverized coal flow operation amount is the actual value. The triangle is the optimum action calculated by the molten iron temperature control device 1. The operator agreed with all the optimum actions prompted by the molten iron temperature control device 1. Therefore, with respect to the Figure 10 The optimum action and the actual operation (actual value) of the pulverized coal ratio operation amount and the pulverized coal flow operation amount are in agreement. As shown in Figure 10 The pulverized coal ratio and the pulverized coal flow, as shown in Figure 10 The coke ratio was gradually decreased by the manual operation of the operator, but as shown in the pulverized coal ratio of Figure 10 The molten iron temperature control device 1 increased the target value of the pulverized coal ratio, thereby offsetting the effect of the decrease in the coke ratio on the molten iron temperature. That is, the molten iron temperature was controlled near the target value.

[0142] [Example 4]

[0143] In this example, the automatic mode was used as the control mode of the molten iron temperature control device 1 during a period different from that of Example 3, and the operation was implemented by operating the pulverized coal ratio and the pulverized coal flow. τl was 40 [minutes].

[0144] Figure 11 is a graph showing the changes in the molten iron temperature, the coke ratio, the pulverized coal ratio, the pulverized coal flow, the blast flow, the pig iron production rate, and the inferior raw material charging ratio for 11 days.

[0145] Figure 11 The molten iron temperature of shows the difference from the target value of the molten iron temperature at time zero. Figure 11 The graphs other than the molten iron temperature of set the period average value to zero. As a result of the automatic operation of the pulverized coal ratio and the pulverized coal flow by the molten iron temperature control device 1 during all the periods in the graph, the molten iron temperature shifted in the range of -25 to 35 °C, and the automatic control of the molten iron temperature could be implemented. In addition, on the 9th day, the blast flow was decreased due to the deterioration of the gas permeability, and thus the molten iron temperature was decreased, but the molten iron temperature was controlled near the target value by increasing the pulverized coal ratio. Also, although the plant (yard) sinter and the plant coke were used during all the periods in the graph, the variation in the molten iron temperature was suppressed. As such, it was confirmed that the control performance of the molten iron temperature control device 1 was good even under severe operating conditions such as the decrease in the blast due to the deterioration of the gas permeability or the use of the inferior raw material.

[0146] (Molten iron temperature control system)

[0147] Figure 12is a block diagram showing a configuration example of a molten iron temperature control system provided with the molten iron temperature control device 1. The molten iron temperature control system is configured to be provided with the molten iron temperature control device 1 and a terminal device 3. In addition, the molten iron temperature control system can further be provided with an operation database 2. In the molten iron temperature control system, the molten iron temperature control device 1 can be provided with a communication section 14 that performs transmission and reception of operation information, in addition to the calculation section 11, the determination section 12, and the prompting section 13. The communication section 14 particularly transmits the optimal action, operation information, and the like to the terminal device 3. In addition, in the molten iron temperature control system, the molten iron temperature control device 1 can perform prompting via the terminal device 3 instead of direct prompting. Therefore, the prompting section 13 functions as an output section that outputs the optimal action, operation information, and the like to the communication section 14. The terminal device 3 is, for example, a device used by an operator. The terminal device 3 can be a mobile terminal such as a smartphone or a tablet. The operation equipment 4 is equipment used in the operation of a blast furnace. The molten iron temperature control system is configured to be able to communicate with the operation equipment 4 via a network, and, for example, output a set value of an operation variable that has been updated in accordance with the optimal action to the operation equipment 4. In the molten iron temperature control system, the molten iron temperature control device 1 performs the above-described processing, and the optimal action and operation information are displayed on the terminal device 3. The operator can output a set value of an operation variable to the operation equipment 4 in accordance with an instruction by operating the terminal device 3. In addition, the molten iron temperature control device 1 can also receive an instruction of operation information from the operator via the communication section 14. Figure 5-7 Such a screen, for example, outputs a set value of an operation variable to the operation equipment 4 in accordance with an instruction by the operator operating (giving an instruction). In addition, the molten iron temperature control device 1 can also receive an instruction of operation information from the operator via the communication section 14.

[0148] (Terminal Device)

[0149] The terminal device 3 is provided with an acquisition section 131, a display section 132, and an interface section 133. The acquisition section 131 acquires the optimal action and operation information related to the optimal action including the compliance sentence. The display section 132 displays the acquired optimal action and operation information in a manner including the compliance sentence. For example, the display section 13 can display operation information including a compliance sentence and a plurality of operation conditions, with the operation conditions being displayed together with a priority order (see FIG. 6). Figure 7 The interface section 133 receives an instruction of the displayed operation information and outputs a set value of an operation variable in accordance with the instruction or based on a lapse of a prescribed time. Here, the output of the set value of the operation variable to the operation equipment 4 can be performed directly by the interface section 133 or via the molten iron temperature control device 1.

[0150] The molten iron temperature control device 1, the operation database 2, the terminal device 3, and the operation equipment 4 are configured to be able to communicate with each other via a network such as a LAN (Local Area Network) or the Internet. Here, Figure 12 The structure of FIG. 1 is one example. The molten iron temperature control device 1 and the terminal device 3 can not include the operation database 2. Figure 12all the illustrated constituent elements. In addition, the molten iron temperature control device 1 and the terminal device 3 can be provided with Figure 12 constituent elements other than those illustrated. In addition, the constituent elements included in each of the molten iron temperature control device 1 and the terminal device 3 are not limited to Figure 12 the example. For example, the determination section 12 and the display section 132 can be located in the same device. In addition, for example, in the case where the constituent elements provided in the molten iron temperature control device 1 are partly located on the terminal device 3 side Figure 12 . In addition, for example, in the case where the constituent elements provided in the terminal device 3 are partly located on the molten iron temperature control device 1 side Figure 12 . Thus, the molten iron temperature control system configured of the molten iron temperature control device 1 and the terminal device 3 can be configured to have the calculation section 11, the determination section 12, the prompting section 13 (output section), the communication section 14, the acquisition section 131, the display section 132, and the interface section 133 as a whole.

[0151] As described above, the molten iron temperature control method, the molten iron temperature control device 1, the molten iron temperature control system, and the terminal device 3 according to the present embodiment can suppress excessive action and show the basis of the calculation of the optimal action by the above-described procedures and configurations. In the present embodiment, in the automatic control (automatic mode), the basis of the calculation is also prompted to the operator, and thus the operator can have a sense of acceptance. In addition, the operation amount prompting screen having the agree button and the do not adopt button is suitable for the operator to quickly instruct agreement or do not adopt, and for example, is preferably an interface where judgment needs to be made every few minutes for the operation of the blast furnace and the like.

[0152] The present embodiment has been described above, but the present disclosure is not limited by the description and the drawings that form a part of the present disclosure based on the present embodiment. For example, a change in the operation variable for the molten iron temperature control results in a change in the gas temperature at the front end of the tuyere. From the viewpoint of equipment maintenance such as the tuyere refractory and suppression of deterioration of the gas permeability caused by unburned coal powder, it is preferable that the gas temperature at the front end of the tuyere be within a prescribed range. Thus, it is possible to visualize how the gas temperature at the front end of the tuyere will change in the case where the optimal action calculated by the molten iron temperature control device 1 is implemented in the operation amount prompting screen. That is, other embodiments, examples, and application techniques and the like completed by those skilled in the art and the like based on the present embodiment are all included in the technical scope of the present disclosure.

[0153] Explanation of Reference Signs

[0154] 1 … molten iron temperature control device; 2 … operation database; 3 … terminal device; 4 … operation device; 11 … calculation section; 12 … determination section; 13 … prompting section (output section); 14 … communication section; 31 … sentence indicating the intention of the best action; 32 … prompting basis of the best action; 33 … best operation amount; 34 … agree button; 35 … do not adopt button; 36 … timer; 41 … sentence indicating the intention of the best action; 42 … prompting basis of the best action; 43 … best operation amount; 44 … agree button; 45 … do not adopt button; 131 … acquisition section; 132 … display section; 133 … interface section.

Claims

1. A molten iron temperature control method characterized by, comprises: a calculation step of calculating a coal powder ratio operation amount so that a molten iron temperature predicted by a physical model capable of calculating a state in a blast furnace falls within a target range set in advance, and calculating a coal powder flow operation amount by coal powder ratio follow-up control in order to compensate for a deviation of a target value of a coal powder ratio considering the coal powder ratio operation amount from a current actual value of the coal powder ratio, and giving priority to the molten iron temperature control or the coal powder ratio follow-up control as an optimal action based on a size of a deviation of the target value of the coal powder ratio from the actual value; a determination step of determining a basis of the calculation related to the optimal action and adding a basis sentence indicating the basis to a sentence; and a presentation step of presenting operation information including at least one of the coal powder ratio operation amount and the coal powder flow operation amount calculated as the optimal action and the basis sentence.

2. The molten iron temperature control method according to claim 1, wherein in a case where an absolute value of the coal powder flow operation amount is larger than an operation amplitude of a coal powder flow capable of being changed at a time, the calculation step gives priority to the coal powder ratio follow-up control without taking the coal powder operation amount calculated by the molten iron temperature control into account in the target value of the coal powder ratio.

3. The molten iron temperature control method according to claim 1 or 2, wherein in a case where a molten iron temperature predicted value calculated in consideration of the coal powder flow operation amount deviates from the target range of the molten iron temperature, the calculation step gives priority to the molten iron temperature control, taking the coal powder operation amount calculated by the molten iron temperature control into account in the target value of the coal powder ratio.

4. The molten iron temperature control method according to any one of claims 1 to 3, wherein the determination step adds a plurality of sentences to the basis sentence, the plurality of sentences include a plurality of change contents arranged in order from near to far from a current time or in order from large to small in a change amount.

5. The molten iron temperature control method according to any one of claims 1 to 4, wherein the operation information is an operation amount presentation screen having a sentence indicating an intention of the optimal action, a basis of the calculation of the optimal action, an approval button, and a non-employment button, the approval button is used in a case where an operator agrees with the optimal action shown in the operation amount presentation screen, the non-employment button is used in a case where the operator does not employ the optimal action shown in the operation amount presentation screen.

6. The molten iron temperature control method according to claim 5, wherein the presentation step has a semi-automatic mode in which an optimal action is executed with approval of the operator and an automatic mode in which an optimal action is executed even without approval of the operator as a control mode, in a case where the control mode is the automatic mode, the operation information is an operation amount presentation screen further having a timer, The timer displays a time from a time when a display related to the optimal action is updated to a predetermined prescribed time, and when the non-acceptance button is not selected before the prescribed time, the optimal action is executed.

7. A molten iron temperature control device characterized by comprising: Possessing: a calculation section that calculates a pulverized coal ratio operation amount so that a molten iron temperature predicted by a physical model that can calculate a state in a blast furnace falls within a target range set in advance, calculates a pulverized coal flow operation amount so as to compensate for a deviation of a target value of the pulverized coal ratio that takes the pulverized coal ratio operation amount into account from a current actual value of the pulverized coal ratio, and prioritizes the molten iron temperature control or the pulverized coal ratio follow-up control as an optimal action based on a size of a deviation of the target value of the pulverized coal ratio from the actual value; a determination section that determines a basis of the calculation related to the optimal action and appends a basis sentence that indicates the basis; and a presentation section that presents operation information including at least one of the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action and the basis sentence.

8. The molten iron temperature control device according to claim 7, wherein in a case where an absolute value of the pulverized coal flow operation amount is greater than an operation range of the pulverized coal flow that can be changed each time, the calculation section prioritizes the pulverized coal ratio follow-up control and does not take a pulverized coal operation amount calculated by the molten iron temperature control into account in the target value of the pulverized coal ratio.

9. The molten iron temperature control device according to claim 7 or 8, wherein in a case where a molten iron temperature prediction value calculated taking the pulverized coal flow operation amount into account deviates from the target range of the molten iron temperature, the calculation section prioritizes the molten iron temperature control and takes a pulverized coal operation amount calculated by the molten iron temperature control into account in the target value of the pulverized coal ratio.

10. The molten iron temperature control device according to any one of claims 7 to 9, wherein the determination section appends a plurality of sentences to the basis sentence, the plurality of sentences include a plurality of change contents arranged in order from near to far from a current time or in order from large to small in a change amount.

11. The molten iron temperature control device according to any one of claims 7 to 10, wherein the operation information is an operation amount presentation screen that has a sentence indicating an intention of the optimal action, a basis of the calculation of the optimal action, an acceptance button, and a non-acceptance button, the acceptance button is used in a case where an operator agrees with the optimal action shown in the operation amount presentation screen, the non-acceptance button is used in a case where the operator does not accept the optimal action shown in the operation amount presentation screen.

12. The molten iron temperature control device according to claim 11, wherein the presentation section has a semi-automatic mode that executes an optimal action with approval of the operator and an automatic mode that executes an optimal action even without approval of the operator as a control mode, In a case where the control mode is the automatic mode, the operation information is an operation amount prompting screen further having a timer, the timer displays a time from a time when a display related to the optimal action is updated to a predetermined prescribed time, and when the non-adopt button is not selected before the prescribed time, the optimal action is executed.

13. A molten iron temperature control system configured to have a molten iron temperature control device and a terminal device, characterized by comprising: a molten iron temperature control device; a terminal device; and a communication device configured to communicate between the molten iron temperature control device and the terminal device. characterized by comprising: a calculation section that calculates a pulverized coal ratio operation amount so that a molten iron temperature predicted by a physical model capable of calculating a state in a blast furnace falls within a target range set in advance, calculates a pulverized coal flow operation amount by a pulverized coal ratio follow-up control in order to compensate for a deviation of a target value of a pulverized coal ratio considering the pulverized coal ratio operation amount from an actual value of the pulverized coal ratio, and prioritizes the molten iron temperature control or the pulverized coal ratio follow-up control as an optimal action based on a size of a deviation of the target value of the pulverized coal ratio from the actual value; a determination section that determines a basis of calculation related to the optimal action and adds a basis sentence indicating the basis; an output section that outputs operation information including at least one of the pulverized coal ratio operation amount and the pulverized coal flow operation amount calculated as the optimal action and the basis sentence; a communication section that performs transmission and reception of the operation information; an acquisition section that acquires the optimal action and the operation information related to the optimal action including the basis sentence; a display section that displays the acquired optimal action and operation information in a manner including the basis sentence; and an interface section that accepts an instruction with respect to the displayed operation information and outputs a set value of an operation variable in accordance with the instruction or based on an elapsed time.

14. A terminal device that constitutes a molten iron temperature control system together with a molten iron temperature control device that outputs operation information including at least one of a pulverized coal ratio operation amount and a pulverized coal flow operation amount calculated as an optimal action and a basis sentence indicating a basis of calculation related to the optimal action based on a size of a deviation of a target value of a pulverized coal ratio from an actual value of the pulverized coal ratio in order to control a molten iron temperature, the terminal device characterized by comprising: an acquisition section that acquires the optimal action and the operation information related to the optimal action including the basis sentence; a display section that displays the acquired optimal action and operation information in a manner including the basis sentence; and an interface section that accepts an instruction with respect to the displayed operation information and outputs a set value of an operation variable in accordance with the instruction or based on an elapsed time.

15. The terminal device according to claim 14, characterized in that the operation information includes a plurality of operation conditions and is displayed together with a priority order. ​

Images