JP4677955B2 - Converter blowing control method, converter blowing control device, and computer program - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a converter blowing control method, a converter blowing control device, and a computer program that can control the carbon concentration and temperature of molten steel at the time of blowing in a converter.

  In converter blowing, static control (static control) and dynamic control (dynamic control) based on measured values using a sub lance to match the carbon concentration and temperature of the molten steel at the time of blowing with the target values. Blowing control is performed in combination.

In static control, the amount of blown oxygen required to make the carbon concentration and temperature of the molten steel coincide with the target values by using a mathematical model based on the mass balance and heat balance before the start of blowing, and the coolant The amount of input of various auxiliary materials, including, is determined and blown according to this.
In dynamic control, the carbon concentration and temperature of molten steel are measured using a sublance during blowing, and the blown oxygen amount determined by static control is determined by a mathematical model based on the mass balance and heat balance, and Modify the amount of input of various auxiliary materials to improve the control accuracy of blowing. This measurement is generally performed by subtracting a predetermined amount from the amount of blown oxygen obtained by static control or the timing of subtracting the coolant cut-out and charging time during dynamic control from the time until the blow-off obtained by static control. It was only done at the timing of blowing oxygen.

  In recent years, with the improvement of hot metal pretreatment technology and secondary refining technology, the need for blow-down operation (operation targeting a carbon concentration lower than the product standard carbon concentration) in converters mainly aimed at dephosphorization has been reduced. As a result, the degree of freedom of the molten steel carbon concentration target value at the time of converter blowing is greater than before. In other words, carbon concentration close to the product standard carbon concentration is set as the target value of direct converter, and blowdown operation that avoids the costly disadvantageous blowdown operation as much as possible is aimed at to reduce the production cost. It is becoming. By aiming at such blowing, the range of the target carbon concentration between charges is wider than the conventional range, and a highly precise technique for converter blowing control is required.

  As mentioned above, as a technology of converter blowing control under the situation where the degree of freedom of the target value of molten steel carbon concentration at the time of converter blowing is large, the timing of the sublance measurement, which is the starting point of dynamic control, Patent Document 1 discloses an invention in which a target is selected from a plurality of preset patterns corresponding to whether or not a target blown carbon concentration and a blown sublance measurement are performed. An object of the present invention is to determine the sublance measurement timing in consideration of fluctuations in decarbonation efficiency at the end of blowing, and to improve the control accuracy of dynamic control.

Specifically, a target carbon concentration at the time of sublance measurement is set in advance based on the presence / absence of hot metal pretreatment and the target blown carbon concentration, and the sublance measurement is performed at the timing when the carbon concentration is reached. The time required for charging the auxiliary material after measuring the sublance is the time required for dynamic control, but the inventor believes that this time is constant regardless of the carbon concentration at the time of blowing. The target carbon concentration of the sublance measurement is obtained by previously calculating the amount of decarburization during the time from a model formula indicated by decarbonation efficiency and adding this amount of decarburization to the target carbon concentration of blowing.
Japanese Patent No. 2996576

  However, with the difference in hot metal conditions and changes over time, the relationship between the decarbonation efficiency and the carbon concentration varies with each charge. Therefore, as in Patent Document 1, the relationship between the predetermined decarbonation efficiency and the carbon concentration is As a base, when the sublance measurement is performed based on the target carbon concentration estimated according to the decarburization amount during the time set in advance, the measurement timing is too late, and the time required for dynamic control, that is, the auxiliary material such as the coolant is added. There is a possibility that the time for charging cannot be secured and the temperature cannot be lowered to the target value.

  In addition, a change in the oxygen flow rate (oxygen flow rate) according to the number of times the converter is used and a change in the oxygen flow rate for the purpose of stabilizing the operation are generally performed in actual operation. When the decarburization amount is calculated and the oxygen flow rate is different from the oxygen flow rate, even if the relationship between decarbonation efficiency and carbon concentration is consistent with the model, the time required for dynamic control May not be secured. That is, using the estimated carbon concentration directly in determining the timing of the sublance measurement has a problem from the viewpoint of securing the dynamic control time.

  As described above, in general, the time required for adding the auxiliary material after the sublance measurement is the time required for the dynamic control. However, the criteria for determining the auxiliary material input time are the target material and the occasional time. The time required for dynamic control is not always constant, depending on the operating conditions. However, as described above, the invention of Patent Document 1 calculates the amount of decarburization on the assumption that the time is constant, and considers that it corresponds to a wide range of blowing target carbon concentrations. However, there is a problem that the basic and important requirement that the measurement is performed when the carbon concentration is sufficiently high and the time necessary for dynamic control is secured cannot be satisfied.

The present invention has been made in view of such circumstances, and determines the time required for dynamic control in accordance with information such as operating conditions such as the amount of input of auxiliary materials, target values of ingredients and materials, and the like. By determining the timing of measuring the carbon concentration and temperature by sublance based on the measured time, even if the target carbon concentration changes over a wide range for each charge, it matches the target carbon concentration at the time of blowing and the coolant etc. Converter blowing control method, converter blowing control device, and computer program capable of ensuring the time for charging the secondary raw material and meeting the target temperature and having good dynamic control accuracy The purpose is to provide.

Further, the present invention obtains an estimated carbon concentration at the determined sublance measurement timing, and when the time is corrected based on the calculated estimated carbon concentration, the sublance measurement timing is determined again based on the corrected time. This makes it possible to more reliably match the target carbon concentration, secure the auxiliary material charging time, match the target temperature, and further improve the dynamic control accuracy. It is an object to provide a method, a converter blowing control device, and a computer program.

The converter blow smelting control method according to the first aspect of the present invention determines the amount of blown oxygen and the amount of auxiliary raw material required to reach the target values of the carbon concentration and temperature of the molten steel at the time of blowing, Static control in which blowing is performed based on the raw material input amount, and the operation in which the blowing oxygen amount and auxiliary raw material input amount are corrected based on the carbon concentration and temperature measured using a sublance during the blowing. In the converter blowing control method for performing the dynamic control, the step of determining the time required for the dynamic control based on the information including the determined input amount of the auxiliary raw material and the target values of the components and materials, and the time and the blowing based on the oxygen flow rate, calculating the amount of oxygen in said time, the time when the oxygen amount obtained by subtracting the amount of oxygen from the blown oxygen amount is blown, determined as the timing of the carbon concentration and the temperature measurement by the sub-lance Characterized by a step of.

In the present invention, the time is determined in accordance with information such as operation conditions such as the amount of auxiliary material input, target values of ingredients and materials, etc. Can respond to changes.
Based on the determined time, the timing of the sublance measurement is determined in consideration of the flow rate of the blown oxygen of the charge. Therefore, even if the target carbon concentration changes over a wide range for each charge, it matches the target carbon concentration at the time of blowing. At the same time, it is possible to secure the time for adding the auxiliary material such as the coolant, and to match the target temperature.
Therefore, the accuracy of the dynamic control is good, and it is possible to suppress the excessive blowing operation and reduce the manufacturing cost.

The converter blowing control method according to the second aspect of the present invention is the first aspect of the invention, wherein the estimated carbon concentration at the timing is obtained from the relationship between the decarbonation efficiency and the carbon concentration prepared in advance.
Calculating the amount of oxygen at the time based on the corrected time and the flow rate of the blown oxygen when the time is corrected based on the estimated carbon concentration.

In the present invention, it is determined whether or not the estimated carbon concentration is appropriate as the carbon concentration at the determined sublance measurement timing. When the estimated carbon concentration is inappropriate, for example, the estimated carbon concentration is too low, When it is assumed that the time required for control, i.e., it is necessary to stop blowing in a time shorter than the auxiliary material charging time, the time used for calculating the sublance measurement timing is corrected to be longer, and the sublance measurement timing is corrected. Therefore, it is possible to more reliably and stably match the target carbon concentration and to secure the auxiliary material charging time.
Therefore, the accuracy of the dynamic control is further improved, and it is possible to suppress the excessive blowing operation and reduce the manufacturing cost.

The converter blow smelting control device according to the third aspect of the present invention determines the blown oxygen amount and the auxiliary material input amount required for the carbon concentration and temperature of the molten steel at the time of blowing to reach the target values by the calculation unit, Based on the static control in which blowing is performed based on the oxygen amount and the input amount of the auxiliary raw material and the carbon concentration and temperature measured using the sub lance during the blowing, the blown oxygen amount and the auxiliary raw material input amount are corrected and blown. In the converter blowing control apparatus that performs dynamic control for performing smelting, the calculation unit calculates the time required for dynamic control based on information including the determined input amount of the auxiliary raw material and target values of components and materials. and time determination means for determining, based on the flow rate of the time and blow oxygen, and means for calculating the amount of oxygen in said time, the time when the oxygen amount obtained by subtracting the amount of oxygen from the blown oxygen amount is blown, the sub-lance Carbon concentration and temperature due to Characterized in that it comprises a means for determining a timing of the measurement.

In the present invention, the time is determined in accordance with the operating conditions such as the input amount of the auxiliary raw material, information on the target values of the ingredients and materials, and the timing of the sublance measurement is determined based on the determined time. Even if the target carbon concentration changes over a wide range every time, it is possible to match the target carbon concentration at the time of blowing, and to secure the time for adding auxiliary materials such as coolant.

  According to a fourth aspect of the present invention, there is provided a converter blowing control apparatus according to the third aspect of the present invention, wherein the estimated carbon concentration at the timing is obtained from a previously prepared relationship between the decarbonation efficiency and the carbon concentration; Based on the corrected time and the flow rate of the blown oxygen, a means for calculating an oxygen amount at the time is provided.

If in the present invention, based on the estimated carbon concentration at the timing of the determined sub-lance measurement, the said time is modified, since re-determine the timing of the sub-lance measurement, more reliably, stably, it matches the target carbon concentration In addition, it is possible to secure the auxiliary material charging time.

  The converter blowing control device according to a fifth aspect of the present invention includes the storage unit according to the third or fourth aspect, wherein the time set in advance for each condition including the input amount of the auxiliary raw material and the target values of the component and the material. The table is stored in the storage unit, and the time determination means selects a time that meets the conditions of the blowing to be performed from the table.

  In the present invention, it is possible to easily select an appropriate time based on past results and the like.

A computer program according to a sixth aspect of the invention causes a computer to determine the amount of blown oxygen and the amount of auxiliary material required to reach the target values of the carbon concentration and temperature of the molten steel at the time of blowing, and the amount of blown oxygen and auxiliary material Static control for performing blowing based on the input amount, and dynamic for performing blowing by correcting the injected oxygen amount and the auxiliary material input amount based on the carbon concentration and temperature measured using a sub lance during the blowing. In the computer program for performing the control, the computer causes the computer to determine the time required for dynamic control based on the information including the determined amount of blown oxygen and the amount of auxiliary raw material input, and the computer sets the time and the amount of blown oxygen. A procedure for calculating the amount of oxygen at the time based on the flow rate, and a time when oxygen is blown into the computer by an amount obtained by subtracting the amount of oxygen from the amount of blown oxygen. Characterized in that it comprises a procedure for determining the timing of the measurement of carbon concentration and temperature by the sub-lance.

In the present invention, the time is determined in accordance with the operating conditions such as the input amount of the auxiliary raw material, information on the target values of the ingredients and materials, and the timing of the sublance measurement is determined based on the determined time. Even if the target carbon concentration is changed over a wide range every time, it is possible to match the target carbon concentration at the time of blowing, and to secure the time for adding auxiliary materials such as a coolant.

  A computer program according to a seventh invention is the computer program according to the sixth invention, wherein the computer causes the computer to obtain an estimated carbon concentration at the timing based on a relationship between a decarbonation efficiency and a carbon concentration prepared in advance. And when the time is corrected, the computer includes calculating the oxygen amount at the time based on the corrected time and the flow rate of the blown oxygen.

If in the present invention, based on the estimated carbon concentration at the timing of the determined sub-lance measurement, the said time is modified, since re-determine the timing of the sub-lance measurement, more reliably, stably, it matches the target carbon concentration In addition, it is possible to secure the auxiliary material charging time.

According to the first, third and sixth inventions, the time required for the dynamic control is determined in accordance with the operating conditions such as the input amount of the auxiliary raw material, the information such as the target values of the components and materials, and the determined time Therefore, the timing of measuring the carbon concentration and temperature by the sublance is determined in consideration of the flow rate of the blown oxygen of the charge, so even if the target carbon concentration changes over a wide range for each charge, the target carbon concentration is At the same time, it is possible to secure a time for adding the auxiliary material such as the coolant, and to reach the target temperature.
Therefore, the accuracy of the dynamic control is good, and it is possible to suppress the excessive blowing operation and reduce the manufacturing cost.
According to the fifth aspect, it is possible to easily select an appropriate time based on past results and the like.

According to the second, fourth and seventh inventions, it is determined whether or not the estimated carbon concentration at the determined sublance measurement timing is appropriate. If the estimated carbon concentration is inappropriate, for example, the estimated carbon concentration is too low, and the auxiliary raw material input When it is assumed that the air blow must be stopped in a time shorter than the time, the time required for dynamic control, which is used to calculate the sublance measurement timing, is corrected to be longer, and the sublance measurement timing is re-determined. This makes it possible to match the target carbon concentration and to secure the time for charging the auxiliary material.
Therefore, the accuracy of dynamic control is even better.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
Embodiment 1 FIG.
FIG. 1 is a functional block diagram showing an internal functional configuration of a converter blowing control apparatus 1 according to Embodiment 1 of the present invention. The converter blowing control device 1 is configured using a general-purpose computer such as a personal computer or a server device.
The converter blowing control device 1 includes a CPU (arithmetic unit) 11 that performs computation, a RAM 12 that stores temporary information generated along with the computation, an external storage device 13 such as a CD-ROM drive, a hard disk, and the like. Internal storage device 14.

The CPU 11 reads the computer program 100 of the present invention from the recording medium 10 such as a CD-ROM by the external storage device 13 and stores the read computer program 100 in the internal storage device 14. The computer program 100 is loaded from the internal storage device 14 to the RAM 12 as necessary. Based on the loaded computer program 100, the CPU 11 executes processing necessary for the converter blowing control device 1.
Moreover, the converter blowing control apparatus 1 is provided with the input parts 15, such as a mouse and a keyboard, and becomes a structure which an operator inputs required data. Furthermore, the converter blowing control device 1 includes an output unit 16 as a display device, and the output unit 16 displays a sublance measurement timing set as described later, an estimated carbon concentration at the time of measurement, and the like. Is done.

FIG. 2 is a flowchart showing the processing procedure of the CPU 11 of the converter blowing control device 1.
The CPU 11 of the converter blowing control device 1 executes the following processing according to the computer program 100 of the present invention loaded in the RAM 12.
The CPU 11 includes hot metal weight for each charge, hot metal components (C, Si, Mn, P, etc.), data indicating hot metal conditions such as hot metal temperature, scrap weight, components for each charge (C, Si, Mn, P, etc.), Data indicating target values such as temperature and material code, and data indicating operating conditions such as the number of furnaces, oxygen flow rate (flow velocity), and lance height are acquired from the input unit 15, set, and stored in the internal storage device 14. (Step S1).

And CPU11 uses the data which show the said hot metal conditions, and the data which show a target value, in order to make the carbon concentration and temperature of molten steel correspond with a target value according to the numerical model etc. based on a mass balance and a heat balance. The amount of oxygen blown in and the amount of auxiliary material input necessary for the calculation are calculated (step S2). For example, the blown oxygen amount is calculated to be 7000 Nm ³ , the input amount of the auxiliary raw material 1 is 1 ton, the input amount of the auxiliary raw material 2 is 1.5 ton, and the like.
The calculated blown oxygen amount and auxiliary material input amount are stored in addition to the operating conditions stored in the internal storage device 14 (step S3).

The CPU 11 determines the time (T _SL ) required for dynamic control based on the data indicating the hot metal conditions, the data indicating the target value, and the data indicating the operating conditions including the amount of blown oxygen and the amount of the auxiliary raw material input (step S4). ). For example, as shown in Table 1 below, T _SL is set for each condition such as material code, C component target value (concentration), P component target value (concentration), auxiliary raw material 1 input amount, and auxiliary raw material 2 input amount. The CPU 11 stores in advance in the internal storage device 14, and the CPU 11 determines _TSL based on this Table 1.

For example, if the hot metal conditions and target value data set in step S1 are material code: aaa2, C component target value (concentration): 0.05%, P component target value: 0.015%,. From 1, T _SL is set to 90 seconds.

Using the determined T _SL and the oxygen flow rate (V _O2 ) set as the operation condition, the CPU 11 calculates the oxygen amount O _SL blown after the sublance measurement according to the following equation (1) (step S5).

For example, if the oxygen flow rate is set to 10 (Nm ³ / sec) in the operating condition data, the oxygen amount O _SL after the sublance measurement is 900 Nm ³ (= 10 × 90).

Then, CPU 11 determines the time when the amount of oxygen obtained by subtracting the O _SL from blowing oxygen amount determined in step S2 is blown as the timing of measurement of the sub-lance (step S6).
For example, the oxygen's crowded blowing the time of 6100Nm ³ minus the 900 Nm ³ from the blow oxygen 7000 nm ³ which has been calculated in step S2 becomes the timing of measurement of the sub-lance.

CPU11 performs the static control which performs blowing according to the blowing oxygen amount calculated by step S2, the auxiliary | assistant raw material input amount, etc. (step S7).
Then, at the sublance measurement timing determined in step S6, the carbon concentration and temperature of the molten steel are measured using the sublance (step S8). Based on the obtained carbon concentration and temperature, the blown oxygen amount and the auxiliary material input amount calculated in step S2 are corrected by a mathematical model based on the material balance and the heat balance (step S9). Then, dynamic control is performed based on the corrected blown oxygen amount and auxiliary material input amount (step S10), and the process is terminated.

In the present embodiment, T _SL is determined in accordance with information such as the operating conditions such as the input amount of auxiliary raw materials, target values of ingredients and materials, etc., so that T _SL , that is, coolant, etc., depends on the materials, operating conditions, etc. It is possible to cope with the change of the auxiliary raw material charging time.
And since the timing of sublance measurement is determined based on the determined T _SL , even if the target carbon concentration changes over a wide range for each charge, the target carbon concentration is matched at the time of blowing and the auxiliary feed time is secured. The target temperature can be reached.
Therefore, the accuracy of the dynamic control is good, and it is possible to suppress the excessive blowing operation and reduce the manufacturing cost.

Embodiment 2. FIG.
The internal configuration of the converter blowing control apparatus according to Embodiment 2 of the present invention is the same as that of the converter blowing control apparatus 1 according to Embodiment 1. The computer program is different from the computer program 100 according to the first embodiment.

FIG. 3 is a flowchart showing a processing procedure of the CPU 11 of the converter blowing control apparatus according to the second embodiment.
The CPU 11 acquires, sets, and stores the data indicating the hot metal condition for each charge, the data indicating the target value for each charge, and the data indicating the operation condition in the internal storage device 14 ( Step S11).

And CPU11 uses the data which show the said hot metal conditions, and the data which show a target value, in order to make the carbon concentration and temperature of molten steel correspond with a target value according to the numerical model etc. based on a mass balance and a heat balance. The amount of oxygen blown in and the amount of auxiliary material input necessary for the calculation are calculated (step S12). For example, the blown oxygen amount is calculated to be 7000 Nm ³ , the input amount of the auxiliary raw material 1 is 1 ton, the input amount of the auxiliary raw material 2 is 1.5 ton, and the like.
The calculated blown oxygen amount and auxiliary raw material input amount are stored in addition to the operating conditions stored in the internal storage device 14 (step S13).

The CPU 11 determines the time (T _SL ) required for the dynamic control based on the data indicating the hot metal conditions, the data indicating the target value, and the data indicating the operation conditions including the amount of blown oxygen and the amount of added auxiliary materials (step S14). ). For example, T _SL is determined based on Table 1 above.
If the hot metal condition and target value data set in step S11 are material code: aaa2, C component target value: 0.05%, P component target value: 0.015%, etc., from Table 1, T _SL Is set to 90 seconds.

Next, the CPU 11 uses the determined T _SL and the oxygen flow rate (V _O2 ) set as the operating condition to calculate the oxygen amount O _SL to be blown after the sublance measurement according to the above equation (1) (step S1). S15).
For example, if the oxygen flow rate is set to 10 (Nm ³ / sec) in the operating condition data, the oxygen amount O _SL after the sublance measurement is 900 Nm ³ (= 10 × 90).

Then, CPU 11 determines the time when the amount of oxygen obtained by subtracting the O _SL from blowing oxygen amount obtained in step S12 is blown as the timing of measurement of the sub-lance (step S16).
For example, from the point when the blowing amount of oxygen 7000 nm ³ which has been calculated it elaborate blown oxygen 6100Nm ³ minus the 900 Nm ³ in step S12, the timing of measurement of the sub-lance.

Next, an estimated carbon concentration C _SL at the time of measuring the sublance is obtained (step S17). As shown in FIG. 5, the following formulas (2) to (4) considering the hot metal conditions and the operating conditions as the factors, and the graph showing the relationship between the carbon concentration and the decarbonation efficiency shown in FIG. per equation (2), starting from the吹止Me target carbon concentration C _EP, by determining the concentration of carbon when integrated to the integrated value (shown shaded in FIG. 5) coincides with the amount of oxygen O _SL, C _SL Is obtained.

Examples of the factor X _{i in the} above formulas (3) and (4) include those shown in Table 2 below.

For example,吹止Me target carbon concentration C _EP is 0.1% and O _SL is 900 Nm ^3, as shown in FIG. 5, the carbon concentration at which the integrated value is 900 Nm ³ to C _EP starting When calculated, it is 0.45%, and this is the estimated carbon concentration C _SL at the time of measurement.
In addition, you may decide to prepare the graph which shows the relationship between the carbon concentration of FIG.4 and FIG.5, and a decarbonation efficiency for every condition.

CPU11 displays the timing of the C _SL and sub-lance measurement to the output unit 16 (step S18). The operator confirms the timing of C _SL and sub-lance measurement, determines whether C _SL is appropriate as the carbon concentration at the time of measurement, and inputs it through the input unit 15.
Then, the CPU 11 determines whether or not the determination as to whether or not C _SL is appropriate as the carbon concentration at the time of measurement is obtained from the input unit 15 (step S19).

If the C _SL obtains appropriate and which determines whether the carbon concentration at the time of measurement (step S19: YES), when C _SL is not suitable as a carbon concentration at the time of measurement (step S20: NO), the T _SL The correction is made (step S21), and the process returns to step S15.
CPU11 a predetermined amount T _SL determined in step S14, or acceleration, or reselect T _SL based on Table 1. For example only C _SL is low, the time required for the dynamic control, i.e. when it is assumed that shall Me吹止than in a short time auxiliary raw material charging time, so T _SL becomes longer used to calculate the timing of the sub-lance measurement Correct it. The correction of _TSL may be performed by an operator input.
Further, the CPU 11 may determine whether or not C _SL is appropriate as the carbon concentration at the time of measurement, instead of acquiring it from the operator.

C _SL are suitable as the carbon concentration at the time of measurement (step S20: YES), if the timing of the sub-lance measurement is appropriate, CPU 11 is blown oxygen amount is calculated in step S12, the blowing according auxiliary raw material input or the like The static control to be performed is executed (step S22).
Then, at the determined measurement timing, the carbon concentration and temperature of the molten steel are measured using a sublance (step S23). Based on the obtained carbon concentration and temperature, the blown oxygen amount and the auxiliary material input amount calculated in step S12 are corrected by a mathematical model based on the material balance and the heat balance (step S24). Then, dynamic control is performed based on the corrected blown oxygen amount and auxiliary material input amount (step S25), and the process is terminated.

Incidentally, after modifying the T _SL at step S21, the process returns to step S15, again, to calculate the O _SL at step S15, after determining the timing of the sub-lance measurement at step S16, the suitability seeking C _SL Without determining, static control may be performed by advancing the process to step S22.

In the present embodiment, in advance of the static control, C _SL is, it is determined whether or not suitable as a carbon concentration in the timing of the determined sub-lance measurement, if C _SL is inappropriate timing of sub-lance measurement Correct the T _SL used in the calculation, since re-determine the timing of the sub-lance measurement, more reliably, stably with to meet the target carbon concentration, it is matched to the target temperature to ensure auxiliary material on time I can do it.
Therefore, the accuracy of the dynamic control is further improved, and it is possible to suppress the excessive blowing operation and reduce the manufacturing cost.

It is a functional block diagram which shows the function structure inside the converter blowing control apparatus which concerns on Embodiment 1 of this invention. It is a flowchart which shows the process sequence of CPU of a converter blowing control apparatus. It is a flowchart which shows the process sequence of CPU of the converter blowing control apparatus which concerns on Embodiment 2. FIG. It is a graph which shows the relationship between carbon concentration and decarbonation efficiency. It is a graph which shows the relationship between carbon concentration and decarbonation efficiency.

Explanation of symbols

1 Converter Blowing Control Device 10 Recording Medium 11 CPU
12 RAM
13 External Storage Device 14 Internal Storage Device 15 Input Unit 16 Output Unit 100 Computer Program

Claims (7)

Static control for determining the amount of oxygen blown in and the amount of auxiliary material charged to reach the target values of the carbon concentration and temperature of the molten steel at the time of blowing, and performing blowing based on the amount of oxygen blown in and the amount of auxiliary material charged ,
In a converter blowing control method for performing dynamic control for correcting and blowing the amount of oxygen blown in and the amount of by-product feed based on the carbon concentration and temperature measured using a sublance during the blowing,
A step of determining a time required for dynamic control based on the information including the determined input amount of the auxiliary raw material and the target values of components and materials;
Calculating the amount of oxygen at the time based on the time and the flow rate of blown oxygen;
And determining the time when oxygen is blown by an amount obtained by subtracting the amount of oxygen from the amount of blown oxygen, as a timing for measuring the carbon concentration and temperature by the sublance. Obtaining an estimated carbon concentration at the timing from a relationship between decarbonation efficiency and carbon concentration prepared in advance;
2. The converter blowing control according to claim 1, further comprising: calculating the amount of oxygen at the time based on the corrected time and the flow rate of blown oxygen when the time is corrected based on the estimated carbon concentration. Method. The calculation unit determines the blown oxygen amount and auxiliary material input amount required to reach the target values for the carbon concentration and temperature of the molten steel at the time of blowing, and performs blowing based on the blown oxygen amount and auxiliary material input amount. Converter blowing that performs static control and dynamic control that performs blowing by correcting the amount of injected oxygen and the amount of by-product feed based on the carbon concentration and temperature measured using a sublance during the blowing In the control device,
The computing unit is
Time determining means for determining the time necessary for dynamic control based on the information including the determined amount of auxiliary raw material input and the target values of ingredients and materials;
Means for calculating the amount of oxygen at the time based on the time and the flow rate of blown oxygen;
And a means for determining a point in time when oxygen is blown by an amount obtained by subtracting the amount of oxygen from the amount of blown oxygen, as a timing for measuring carbon concentration and temperature by the sublance. Means for obtaining an estimated carbon concentration at the timing from a relationship between decarbonation efficiency and carbon concentration prepared in advance;
4. The converter blowing control according to claim 3, further comprising: means for calculating an oxygen amount at the time based on the corrected time and the flow rate of the blown oxygen when the time is corrected based on the estimated carbon concentration. apparatus. A storage unit,
In advance, the storage unit stores the table of the time set for each condition including the auxiliary raw material input amount and the target values of the components and materials,
5. The converter blowing control device according to claim 3, wherein the time determination unit selects a time that meets the conditions of the blowing to be performed from the table. Let the computer determine the amount of oxygen blown in and the amount of auxiliary material charged to reach the target values for the carbon concentration and temperature of the molten steel at the time of blowing, and perform static blowing based on the amount of oxygen blown in and the amount of auxiliary material charged. In a computer program for performing automatic control and dynamic control for performing blowing by correcting the blown oxygen amount and by-product feed amount based on the carbon concentration and temperature measured using a sublance during the blowing,
A procedure for causing the computer to determine the time required for dynamic control based on the information including the determined amount of blown oxygen and the amount of auxiliary material input,
A procedure for causing the computer to calculate the amount of oxygen at the time based on the time and the flow rate of the blown oxygen;
And a procedure for causing a computer to determine a point in time when oxygen is blown by an amount obtained by subtracting the amount of oxygen from the amount of blown oxygen as a timing for measuring carbon concentration and temperature by the sublance . A procedure for causing the computer to determine the estimated carbon concentration at the timing from the relationship between the decarbonation efficiency and the carbon concentration prepared in advance
The computer program according to claim 6, further comprising: causing the computer to calculate an oxygen amount at the time based on the corrected time and the flow rate of the blown oxygen when the time is corrected based on the estimated carbon concentration. .

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