KR20030038922A - Cokes input control apparatus in blast furnace - Google Patents

Abstract

PURPOSE: A charging control apparatus for blast furnace is provided to control the amount of nitrogen flown into charging hopper to stabilize distribution of charging materials so that stable shape of the charging materials and the optimum blast furnace state are maintained, and productivity of molten iron is improved. CONSTITUTION: In a charging control apparatus (100) for blast furnace comprising a charging hopper positioned at the upper part of the blast furnace (1), and pressure equalization control valves (7) for supplying nitrogen into the charging hopper and cutting off supply of nitrogen into the charging hopper, the charging control apparatus (100) comprises a weight indication part (20) for outputting detected values of the weight of the charging hopper (3); first operation part (21) for calculating the rotation time in realtime by multiplying rotation cycles by rotation time per unit time when charging is initiated; second operation part (22) for calculating a target value of the charging quantity per unit time by the hopper weight value detected in the weight indication part by the total rotation time calculated in the first operation part; third operation part (23) for calculating actual charging quantities per unit time by receiving the weight detection values outputted from the weight indication part; a subtraction part (24) for obtaining a deviation between the actual charging quantities per unit time and target value calculated in the second and third operation parts; a proportionator (25) for calculating a nitrogen value for compensating the deviation outputted from the subtraction part through a relation between the nitrogen amount and charging quantity supplied into the charging hopper; and a differential pressure control part (28) for controlling opening degree of the pressure equalization control valves according to the nitrogen amount compensation value for compensating deviation of the charging quantity from the proportionator as controlling the pressure equalization control valves so that pressure of the charging hopper is equal to that of the blast furnace during charging.

Description

Charge control device of blast furnace facility {COKES INPUT CONTROL APPARATUS IN BLAST FURNACE}

The present invention relates to a charging facility for charging raw materials and fuel into a bell less type furnace, and more particularly, to control the amount of nitrogen flowing into the charging hopper so that the distribution of the charged material is stabilized. It relates to a charging control device in a blast furnace facility that can maintain the state of the furnace and improve the productivity of the molten iron.

1 is a process diagram schematically showing a general blast furnace facility, the blast furnace facility is a blast furnace (1), a transport device (2) for sequentially transporting fuel and raw materials to be charged into the blast furnace (1), the blast furnace (1) Charge hopper (3) which is installed on the top of the hopper and collects the fuel / raw material conveyed to the conveying device (2) and charges it into the blast furnace (1) by pressure adjustment, and the weight of the charges inside the charge hopper (3). The load cell 5 to be detected, the differential pressure extractor 6 which detects the internal pressure difference between the charging hopper 3 and the blast furnace 1, and the charging hopper 3 are supplied with nitrogen to supply the nitrogen to the blast furnace 1 and the equal pressure. And a distribution device 8 for distributing the contents into the blast furnace 1 by operating at a set tilt angle and turning speed at a lower end of the charging hopper 3 to achieve a pressure equalizing control valve 7. Doing.

Referring to the charging process in the blast furnace installation as described above, in accordance with a predetermined order of the raw material iron ore and fuel coke, is carried to the charging hopper (3) by the transport device 2, the charging hopper (3) The internal pressure of the charging hopper (3) is charged into the blast furnace (1) in order to make it easy to charge into the blast furnace (1) in order from the inside of the blast furnace (1) in order to facilitate the charging into the blast furnace (1) having a high pressure from ) After charging the blast furnace gas and nitrogen to the charging hopper 3 so as to be in the same state as the upper pressure (approximately 1.5 to 2.5 kg / cm 2), the differential pressure between the charging hopper 3 and the blast furnace 1 becomes zero. When done, charging is done via the dispensing device 8.

At this time, a constant layer is formed alternately with the coke layer and the ore layer in the blast furnace 1, and the shape of the charge is divided into parts. Each divided part is referred to as a notch 10. In addition, the amount of the charged material for each notch is charged while the distribution device 8 is rotated by a predetermined number of turns and tilt angles, and the weight change of the hopper 3 generated at this time is the weight detection device 5. It is detected by the controller and transmitted to the process control computer (not shown), so that the driver can check the change of the charge through the monitor.

However, since only the weight of the charging hopper 3 can be known, only the progress of the charging can be known, and it is not possible to confirm whether the actual charging is evenly distributed and the charging of each notch in the blast furnace 1 is accurate.

Therefore, when charging is made in the above-described conventional manner, when various abnormal conditions occur in the blast furnace installation, the contents of the filling cannot be constantly discharged into the blast furnace 1, and as a result, the exact amount of each notch 9 The problem arises that it cannot be distributed. In the above, for example, in the case of abnormal conditions, firstly, when the differential pressure between the pressure inside the blast furnace and the pressure inside the hopper in the charging process is unstable, and secondly, when the particle size change of the charge is largely generated, thirdly, the hopper 3 A mechanical deviation may occur in the valve 11 or the distribution device 8 that opens and closes the lower end.

In addition, in the hopper (3), conventionally, after dispensing the charge while the dispensing device is rotated by a high number of turns, which is predetermined for each notch, it moves to the next notch regardless of the actual charge amount and rotates by the predetermined amount. Charging proceeds irrespective of fluctuations in the discharge rate and the charging amount, and as a result, proper charging is impossible when the charging state is poor.

And when the distribution layer of a charged material fluctuates, since gas will flow irregularly in the blast furnace 1, yellowing will worsen and productivity will fall.

In the past, when the number of turns of the chute and the number of performances do not match, and the charging state becomes poor, the opening degree of the valve 11 installed in the lower portion of the hopper 3 is changed and adjusted, but the various abnormal conditions described above are maintained. However, this problem has a problem that can not solve the charging state defects.

The present invention has been proposed in order to solve the above-mentioned conventional problems, and calculates the total time that the distribution device will rotate when charging the coke, calculates this as the weight change of the charging hopper and compares the discharge with the actual loading of the equalizer It is an object of the present invention to provide a charging control device in a blast furnace facility that is intended to control the discharge of the charge constantly by adjusting the amount of fish nitrogen.

1 is a process configuration diagram showing a charging facility in the blast furnace operation.

2 is a block diagram showing a charging control apparatus according to the present invention.

3 is an operation flowchart of a charging control apparatus according to the present invention.

Figure 4 (a) is a graph showing the weight change of the charging hopper with the time of charging, (b) is a glyph showing the relationship between the amount of loading deviation and the nitrogen change.

* Description of the symbols for the main parts of the drawings *

21 ~ 23: 1st ~ 3rd operation part

24: subtraction part

25: proportioner

26: setting unit

27: selection unit

28: differential pressure control unit

The present invention provides a charging control apparatus for blast furnace equipment comprising a charging hopper located in the upper part of the blast furnace and a pressure equalizing control valve for supplying / blocking nitrogen to the charging hopper as an element for achieving the above object.

A weight indicating unit for outputting a detection value of the weight of the charging hopper;

A first calculation unit which calculates the turning time in real time by multiplying the turning number by the turning time per unit time when charging is started;

A second calculation unit which calculates a charging target value per unit time by dividing the hopper weight value detected from the weight indicating unit by the total turning time calculated by the first calculating unit;

A third calculation unit which receives a weight detection value output from the weight indicating unit and calculates an actual charging amount per unit time;

A subtraction unit for obtaining a deviation between the actual charge amount and the target value per unit time calculated by the second and third calculation units;

A proportioner for calculating a nitrogen value for compensating for the deviation output from the subtracting unit through the relationship between the amount of nitrogen supplied to the charging hopper and the charging amount; And

And a differential pressure control unit for adjusting the opening degree of the equalizing control valve according to the nitrogen amount compensation value for compensating the charging amount deviation from the proportioner while adjusting the equalizing control valve so that the pressure between the charging hopper and the blast furnace is uniform during charging. It is done.

Hereinafter, with reference to the accompanying drawings will be described a charging control device in the blast furnace installation according to the present invention.

In blast furnace installations, iron ore is a considerable weight at the time of actual charging, so even if various charging conditions are not affected, it can be distributed to the notch exactly as the target amount, but because the coke is lighter than iron ore, Edo discharged from the hopper 3 greatly varies.

The present invention has been proposed in view of such a point, and detects the instantaneous coke loading amount, and compares it with the loading target value, so as to enable stable charging of coke even when various abnormalities are generated in the blast furnace equipment, and the charging hopper in proportion to the deviation It is to control the amount of nitrogen flowing into. Since the amount of nitrogen flowing into the charging hopper has a greater influence on the coke charging than the above-described various abnormal factors, the instantaneous loading of the coke can be controlled even if an abnormal factor is generated.

2 is a block diagram showing a configuration of a charging control device according to the present invention, in which the apparatus 100 converts and outputs an output signal of a load cell 5 that detects the weight of the charging hopper 3 into a weight detection value. The first calculation unit 21 and the first calculation unit 21 for calculating the turning time in real time by multiplying the turning number by the turning time per unit time when the charging is started, and the hopper weight value detected by the weight indicating unit 20. A second calculation unit 22 for calculating a target amount of charge per unit time divided by the total turning time calculated in (21) and a weight detection value output from the weight indicating unit 20 to calculate an actual charge amount per unit time; The calculation unit 23, the subtraction unit 24 for calculating the deviation between the actual charge amount and the target value per unit time calculated by the second and third calculation units 22 and 23, the amount of nitrogen supplied to the hopper 3, Is outputted from the subtractor 24 through The proportioner 25 which calculates the nitrogen value which compensates a difference, the setting part 26 which sets the amount of nitrogen supplied to the hopper 3, the nitrogen amount setting value of the said setting part 26, or the said proportioner 25 Selector 27 for selecting one of the nitrogen amount set value to compensate the charging deviation output from the output as a target value, between the target value of the selector 27 and the hopper of the differential pressure detector 6 and the upper part of the blast furnace It includes a differential pressure control unit 28 for adjusting the opening degree of the pressure equalizing control valve 7 so that the nitrogen as much as the target value is supplied as long as the differential pressure is compensated by the PID operation.

3 is a flowchart showing the operation of the charging control apparatus according to the present invention in order, and the operation of the apparatus will be described with reference to the flowchart of FIG.

When coke is filled in the charging hopper 3, the equalizing control valve 7 is opened and nitrogen is supplied to the charging hopper 3. Therefore, when the pressure of the charging hopper 3 is equal to the pressure of the upper part of the blast furnace 1, coke starts to be charged from the charging hopper 3 to the blast furnace 1 by control of a process control computer (not shown). .

At this time, the operation of the charging control device 100 according to the present invention is also started.

That is, as charging is started from the charging hopper 3 to the blast furnace 1, the change in the weight of the charging hopper 3 is detected by the load cell 5 and transmitted to the weight indicating unit 20, the weight indicating unit 20 In accordance with the signal of the load cell 5 outputs the current weight value of the charge in the charging hopper (3) (S302). The detection value of the weight indicating unit 20 is input to the third operation unit 23, and the third operation unit 23 is the actual charging per unit time, divided by t seconds, the difference between the weight value before t seconds and the current weight value. The weight is calculated (S303). Figure 4 (a) is a graph showing the weight change of the charging hopper for each time at the time of charging, as shown, in this step, the unit weight change with respect to the unit time is detected.

In addition, a calculation process for calculating the charging deviation in real time in the apparatus 100 is executed. First, a setting table for setting the number of revolutions and the tilt angle of the distribution apparatus 8 in the first calculation unit 21 (not shown) The number of turns of the distribution device 8 is read from the time), and the total number of turns is multiplied by one turn time to calculate the total turn time (S304).

Next, the second calculation unit 22 calculates a target charging weight value per unit time by dividing the weight of the charge output from the weight indicating unit 20 by the total turning time calculated by the first calculation unit 21 (S306). ).

The deviation between the actual charge amount per unit time and the target charge amount per unit time obtained as described above is calculated by the subtractor 24 (S307), and the proportioner 25 is adjusted according to the degree of increase or decrease of the actual charge amount with respect to the target charge amount. Compensation outputs an amount of nitrogen that can increase or decrease the amount of loading (S308).

That is, as shown in (b) of FIG. 4, the relationship between the variation of the amount of nitrogen that can be compensated for the deviation of the actual loading with respect to the target loading is shown, which means that the pressure between the charging hopper 3 and the blast furnace 1 is equalized. In the state where the charging amount per unit time is a predetermined value, when the pressure of the charging hopper 3 is higher than the blast furnace 1 by a predetermined value, the charging amount per unit time increases by that amount, and the pressure of the charging hopper 3 is higher than that of the blast furnace 1. If it is lowered, the amount of charge per unit time decreases. In the graph of Figure 4b, the charge amount deviation value is shown in the range of -30kg / sec ~ 30kg / sec, the deviation amount out of this range is out of the controllable range, and therefore excluded from the control range of the apparatus 100. The output (compensated nitrogen amount) for the input in the above range is -0.03 to 0.1 kg / cm 2. In addition, in the graph, 0.023kg / cm2 of the loading amount of change of nitrogen amount of 0 is a value capable of maintaining a stable charging state in a steady state in which various abnormalities of the blast furnace facility described above do not occur, and through repeated tests. This value is obtained, and the amount of deviation is increased or decreased based on the value (0.023 kg / cm 2), and the amount of nitrogen is varied accordingly.

As described above, when the nitrogen amount correction value for correcting the loading amount deviation is calculated, it is input to the differential pressure control unit 28 through the selection unit 27, the differential pressure control unit 28 is the amount of nitrogen as the correction value by the PID control The opening degree of the equalization control valve 7 is adjusted to increase / decrease (S308). The action of the differential pressure control unit 28 is already applied, and since it is generally known, a detailed description thereof will be omitted.

In the configuration of FIG. 2, the setting unit 26 sets a nitrogen amount setting value so that the target unit charging amount is normally charged in the normal state in which the above-described abnormal factors do not occur, and is selected by the selecting unit 27. In the state, the setting value of the setting unit 26 is applied to the differential pressure control unit 28 as the nitrogen amount setting value, and when an abnormal factor occurs, the value of the setting unit 26 is cut off and outputted from the proportioner 25. The corrected nitrogen amount is applied to the differential pressure control unit 28 as a target value.

According to the above description, the present invention adjusts the amount of nitrogen flowing into the charging hopper to stabilize the deviation value by forward-calculating the actual discharge amount of the charged product, and thus, even if various abnormalities causing the deviation of the charged amount occur in the blast furnace equipment, Immediate compensation of the charges through the increase and decrease has the effect of minimizing the width of the deviation, there is a good effect to improve the deterioration and degradation of productivity by achieving a stable charging of coke from there.

Claims (2)

In the charging control device of the blast furnace installation comprising a charging hopper located in the upper part of the blast furnace and a pressure equalizing control valve for supplying / blocking nitrogen to the charging hopper, A weight indicating unit for outputting a detection value of the weight of the charging hopper; A first calculation unit which calculates the turning time in real time by multiplying the turning number by the turning time per unit time when charging is started; A second calculation unit which calculates a charging target value per unit time by dividing the hopper weight value detected from the weight indicating unit by the total turning time calculated by the first calculating unit; A third calculation unit which receives a weight detection value output from the weight indicating unit and calculates an actual charging amount per unit time; A subtraction unit for obtaining a deviation between the actual charge amount and the target value per unit time calculated by the second and third calculation units; A proportioner for calculating a nitrogen value for compensating for the deviation output from the subtracting unit through the relationship between the amount of nitrogen supplied to the charging hopper and the charging amount; And And a differential pressure control unit for adjusting the opening degree of the equalizing control valve according to the nitrogen amount compensation value for compensating the charging amount deviation from the proportioner while adjusting the equalizing control valve so that the pressure between the charging hopper and the blast furnace is uniform during charging. Charge control device in blast furnace equipment. The charging control apparatus of the blast furnace installation according to claim 1, wherein the proportional input amount of the deviation is in the range of -30 to 30 kg / sec, and the amount of compensated nitrogen output is -0.03 to 0.1 kg / cm 2.