JP2000320978A - Sintering raw material charging control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress mutual interference generated in two control systems of sintering raw material layer thickness control and raw material mountain inclined surface thickness control and to achieve further improvement of sintering raw material charging state. And a charging control method. SOLUTION: In a control method of a sintering raw material charging apparatus having a sintering raw material layer thickness control system A and a sintering raw material mountain thickness control system B, a straight integration coefficient α, β for each of the control systems A and B; The cross integration coefficients γ and δ are set in advance, and one control system A
Of the straight integration coefficient α
A, and the cross integration value γ · b obtained by integrating the cross integration coefficient γ of one control system A with the deviation proportional integration calculation value b of the other control system B is obtained, and the obtained straight integration value α · a is obtained. Then, the control amount of the operation unit of each control system A is determined from the cross integrated value γ · b, and control of each control system is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging control method for charging a sintering raw material to a sintering pallet via a charging chute.

[0002]

2. Description of the Related Art Fine ore or fine-grained ore is a raw material that, when charged as it is, causes deterioration in air permeability inside the blast furnace and controls the reaction in the furnace. ing. As typical equipment for producing this sintered ore,
There is a Dwyroid type sintering machine. In this Dwyroid type sintering machine, a sintering raw material is charged into an endless chain-shaped sintering pallet by a raw material charging device, and the surface of the charged sintering raw material layer is ignited by an ignition furnace and passed through a wind box. The air above the charged sintering raw material layer is sucked by the air blower, so that the coke breeze mixed in the sintering raw material burns as the sintering pallet moves, and the sintering of the sintering raw material Is carried out, and is discharged as sinter from the sintering pallet in the discharge section.

[0003] When producing sintered ore in a Dwyroid type sintering machine, there are two important factors that affect the quality and productivity of the sintered ore. First, the upper part of the sintering raw material charged on the sintering pallet by the raw material charging device becomes less brittle sinter due to rapid cooling, etc. That is, segregation charging is carried out so as to increase the coke fines and reduce the particle size. This is important for improving the quality and productivity of the sinter. One of the measures that have been proposed to date is a segregation charging method of the sintering raw material by an air classification charging device using a gas blowing nozzle. That is, as shown in FIG. 2, when the sintering raw material 17 dropped and supplied from the hopper 1 through the drum feeder 2 and the raw material cutout gate 3 is charged onto the sintering pallet 10 through the charging chute 7, An opening 4 is provided downstream of the dropping position 14 of the sintering raw material 17 supplied from the cutout gate 3 on the charging chute 7, and a gas blowing nozzle 15 for blowing air from above the opening 4 is provided. By blowing air from the nozzle 15 onto the sintering raw material 17 during the downhilling, only the fine and fine-grained sintering raw material 18 is selectively dropped from the opening 4 so that the sintering raw material 17 and the fine and fine sintering raw material 19 It is separated into granular raw materials 18. Coarse grain sintering raw material 19
Slides down on the charging chute 7 as it is,
The fine and fine-grained sintering material 18 dropped from the opening 4 is deposited on the surface layer of the lower sintering material layer 13 </ b> L made of the coarse-grained sintering material 19.
In the lower portion 13L of the sintering material layer on
In the upper layer 13U of the sintering material layer,
8 and segregate charging.

[0004] Secondly, when sinter is manufactured by a Dwyroid type sintering machine, the charging density, air permeability, ignition state and the like of the sintering raw material layer formed on the sintering pallet are baked. It is easy to change in the pallet width direction. Therefore, unevenness occurs in the combustion state in the width direction of the sintering pallet, and defects such as insufficient sintering and over-burning occur. A sintered ore having a sufficient particle size and strength cannot be obtained from the insufficiently sintered sintering raw material. In addition, the overburned sintering raw material is likely to be powdered during handling. Therefore, none of them can be treated as a sintered ore suitable for charging the blast furnace, and burn unevenness in the pallet width direction may cause a reduction in the quality and productivity of the sintered ore.

As a countermeasure against this point, Japanese Patent Laid-Open Publication No.
In Japanese Patent No. 72872, a plurality of pairs are arranged in the width direction of the sintering pallet with a pair of a thickness sensor for measuring the thickness of the inclined surface of the charging material pile formed on the sintering pallet in front of the lower end of the charging chute and a material extraction gate. Accordingly, a method for adjusting the density distribution in the pallet width direction of the sintering raw material has been proposed. That is, as shown in FIG. 3, a drum feeder 2 provided at the lower end of the hopper 1, a plurality of raw material cutout gates 3 arranged on the peripheral surface of the drum feeder 2 along the rotation axis direction, and further, a raw material cutout gate 3 When charging the sintering raw material 17 onto the sintering pallet 10 via the charging chute 7a provided below, at a position above the inclined surface of the coarse-grained raw material mountain 20 formed on the sintering pallet 10 A raw material mountain inclined surface thickness measuring ultrasonic sensor 16 for measuring the inclined surface thickness 12 of the coarse material raw material mountain 20 arranged in the width direction of the sintering pallet 10 in the same number as the raw material cutout gates 3; Based on the deposition level of the sintering raw material 17 detected by the surface thickness measuring ultrasonic sensor 16, the opening degree of the raw material cutout gate 3 is adjusted by the operation amount signal from the control circuit 22, and The inclined surface thickness 12 is that match controlled to a predetermined set value.

[0006]

The first control of the thickness of the sintering material layer by adjusting the opening of the gas blowing nozzle valve and the second control of the thickness of the slope of the raw material mountain by adjusting the opening of the material cutting gate. The problem when trying to perform each operation independently is that when the operating end of each control system is operated, the other control system is intermixed with disturbance elements, that is, the two control systems interfere with each other. is there. That is, when the opening of the gas spray nozzle valve is changed, the amount of fine / fine-grained sintering material falling from the opening provided in the middle of the charging chute changes.
Naturally, the amount of the coarse-grained sintering raw material loaded on the pallet by sliding down on the charging chute without dropping from the opening also changes, that is, this becomes a disturbance element and the thickness of the raw material mountain slope is temporarily reduced. fluctuate. Conversely, when the thickness of the raw material mountain slope is changed, the amount of fine and fine-grained sintered material falling from the opening also changes as the amount of raw material cut out from the raw material cutout gate changes. It becomes an element and the thickness of the sintering material layer on the sintering pallet changes temporarily. Variations in the raw material mountain slope surface thickness and the sintering material layer thickness as described above adversely affect the ignitability in the ignition furnace and the uniformity of the sintering and firing state inside the sintering material layer. This can be a factor that leads to a decrease in sinter ore yield. The present invention suppresses the mutual interference generated in two control systems of the sintering material layer thickness control and the sintering material mountain thickness control, and loads the sintering material to further improve the sintering material charging state. It is an object to provide a control method.

[0007]

According to the present invention, there is provided a method for controlling charging of a sintering raw material according to the present invention, wherein a sintering raw material in a hopper is cut out by a drum feeder and a raw material cutout gate, and the sintering raw material is fired through a charging chute. At the time of charging on the sintering pallet, the thickness of the sintering material pile formed on the sintering pallet at the time of charging the sintering material onto the sintering pallet from the charging chute is measured. A deviation from the set value is obtained, and the thickness of the sintering raw material pile is controlled by manipulating the opening of the raw material cutout gate based on the deviation proportional integral operation value obtained by performing a proportional integral operation on the deviation. A sintering raw material mountain thickness control system, an opening is provided in the middle of the charging chute, and a gas blowing nozzle for blowing gas toward the sintering raw material sliding down on the charging chute is provided above the opening; The thickness of the sintering material layer deposited on the sintering pallet, which is determined by the amount of the fine / fine-grained sintering material falling from the mouth, is measured, and a deviation between the measured value and a preset value is obtained. A sintering raw material layer thickness control system that controls the sintering raw material layer thickness by manipulating the amount of gas blown from the gas blowing nozzle based on the deviation proportional integral calculated value obtained by performing the proportional integral calculation. In the method for controlling a sintering raw material charging apparatus, a straight integration coefficient and a cross integration coefficient for each control system are set in advance, and a straight proportional integration calculation value of one control system is used to calculate a straight integration coefficient of the one control system. A straight integrated value is obtained by integrating the integration coefficient, and a cross integrated value obtained by integrating the cross integration coefficient of the one control system with the deviation proportional integration operation value of the other control system is obtained. The control amount of the operation unit of each control system is determined from the total integrated value and the cross integrated value, and the control amounts of the respective control systems are controlled so that the control amounts of the two control systems cancel each other's interference. Each signal is given to the operation end of the control system as a final operation amount.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a method of controlling charging of a sintering raw material according to an embodiment of the present invention will be described with reference to FIG. A drum feeder 2, a plurality of raw material cutout gates 3 and a raw material cutout gate driving unit 27 arranged at equal intervals in the width direction are provided below the hopper 1 that accommodates the sintering raw material 17. By the rotation of 2, it is cut out from the lower part of the hopper 1, and falls on the charging chute 7 through the material cutout gate 3. The charging chute 7 is provided with an opening 4 downstream of a position (falling position) 14 where the sintering raw material 17 cut out from the raw material discharging gate 3 falls, and has a width above the opening 4. First gas spray nozzles 1 arranged at equal intervals in multiple directions
5U are installed. The first gas spray nozzle 15U is connected to the gas supply pipe 25 and the gas flow control valve 26.
The gas supplied from the gas supply pipe 25 to the gas blowing nozzle 15U is slid down on the upstream charging chute 7U toward the sintering raw material 17 that has reached the opening 4 from above, and is sprayed from above. By dropping the fine-grained sintering raw material 18 from the opening 4, the sintering raw material 17 is
It is separated from the fine grain sintering raw material 18. The coarse-grained sintering raw material 19 that has not fallen from the opening 4 slides on the downstream charging chute 7L as it is, is charged onto the sintering pallet 10, and is provided below the downstream charging chute 7L. After uniforming the surface layer by 6, the sintering material layer is transferred to the ignition furnace 24 side as the lower layer 13 </ b> L. Further, the fine / fine-grained sintering material 18 dropped from the opening 4 drops and deposits on the surface of the sintering material layer lower layer 13L, and the sintering material layer upper layer 13U.
To form The sintering raw material 17 is charged by the above-described process. In the present invention, the sintering raw material layer thickness control system and the coarse-grained raw material mountain inclined surface thickness (sintering raw material mountain thickness) control system are used. It is a great feature that it has two control systems and a non-interference calculation device, and these will be sequentially described below.

First, FIG. 1 shows a sintering material layer thickness control system A.
Will be described with reference to FIG. A plurality of ultrasonic sensors 16a for measuring the thickness of the sintering raw material layer are arranged at equal intervals in the width direction of the sintering pallet 10 above the sintering pallet 10 slightly upstream of the ignition furnace 24 in the direction of travel of the sintering pallet 10.
Here, the ultrasonic sensor 16a for measuring the thickness of the sintering raw material layer forms a pair with the first gas blowing nozzle 15U having the same positional relationship in the width direction. Then, the measured value of the sintering material layer thickness 11 detected by the sintering material layer thickness measuring ultrasonic sensor 16a corresponding to each of the first gas blowing nozzles 15U and predetermined in each of the six width direction areas. The sintering raw material layer thickness set value X is input to the proportional integral controller 22a of the sintering raw material layer thickness control system A, and a difference between the two inputs is taken inside the proportional integral controller 22a. Perform an integration operation. Subsequently, the deviation proportional integral calculation value is input to the drive unit 26a of the gas flow control valve 26 provided in the gas supply pipe 25 communicating with the first gas blowing nozzle 15U via the non-interference calculation device 23. Thus, the gas supply amount (gas blowing amount) is adjusted. In the above control loop, constant control of the sintering raw material layer thickness 11 is performed.

Next, the control system B for controlling the thickness of the coarse-grained raw material mountain slope (thickness of the raw material mountain) will be described with reference to FIG. The coarse-grained sintering raw material 19 is provided below the downstream charging chute 7L.
A cut gate 6 for evenly leveling the surface layer is provided, and the charged coarse-grained sintering material 19 is deposited in a mountain shape in front of the cut gate 6. A plurality of raw material mountain inclined surface thickness measuring ultrasonic sensors 16b are provided at equal intervals in the width direction of the sintering pallet 10 in front of the inclined surface of the coarse material raw material mountain (sintered raw material mountain) 20 thus deposited. The raw material mountain inclined surface thickness measuring ultrasonic sensor 16b forms a pair with the raw material cutout gate 3 having the same positional relationship in the width direction of the sintered pallet 10. Then, the measured values of the sloped surface thickness (sintered raw material mountain thickness) 12 of the coarse-grained raw material mountain 20 detected by the raw material mountain inclined surface thickness measuring ultrasonic sensor 16b corresponding to each raw material cutout gate 3 and the six widths in advance The coarse-grained raw material mountain slope surface thickness set value Y determined for each area in each direction is input to the proportional-integral controller 22b of the coarse-grained raw material mountain slope-surface thickness control system B, and the two inputs are made inside the proportional-integral controller 22b. , And a proportional integral operation is performed on the deviation. Subsequently, the deviation proportional integration calculation value is input to the raw material cutout gate drive unit 27 via the non-interference calculating device 23, thereby adjusting the opening degree of the raw material cutout gate 3.
In the control loop as described above, the coarse-grained raw material mountain slope surface thickness 1
2 constant control is performed.

Further, the non-interference calculating device 23 will be described in detail with reference to FIG. The input to the non-interference arithmetic unit 23 is an integral signal (deviation proportional integral integral value) calculated by the proportional integral controller 22a of the sintering raw material layer thickness control system A.
a, and an integral signal (deviation proportional integral integral value) b which is proportionally integral computed by the proportional integral controller 22b of the coarse grain material mountain slope control system B. The non-interference calculation device 23 calculates a straight integrated value α · a obtained by integrating the integrated signal a with the straight integrated coefficient α of the sintering raw material layer thickness control system A, and an integrated signal b.
Is calculated from the cross integration value γ · b obtained by integrating the cross integration coefficient γ of the sintering raw material layer thickness control system A, and this is output as the operation amount signal c of the gas flow rate adjustment valve drive section 26a. Further, a straight integrated value β · b obtained by integrating the integrated signal b with the straight integrated coefficient β of the coarse grain raw material mountain slope control system B.
And a cross integration value δ · a obtained by integrating the integration signal a with the cross integration coefficient δ of the coarse-grained raw material mountain slope control system B, and this is used as an operation amount signal d of the raw material cutout gate drive unit 27. Output as That is, the above-mentioned contents are expressed by the following expressions. Operation amount signal c = α · a−γ · b (1) Operation amount signal d = β · b + δ · a (2)

Here, the above equations (1) and (2) will be described in detail. First, the equation (1) is used. The measurement value of the coarse-grained raw material mountain slope thickness measuring ultrasonic sensor 16b (the coarse-grained raw material mountain slope thickness 12) is the coarse-grained raw material mountain slope thickness setting value Y.
If it is smaller, it naturally changes in the direction in which the opening degree of the material extraction gate 3 increases, that is, in the direction in which the integration signal b increases. As a result, since the amount of the raw material cut out on the charging chute 7 increases, the amount of the fine / fine-grained sintering raw material 18 falling from the opening 4 increases. This is a disturbance to the sintering raw material layer thickness control system A, and the value measured by the sintering raw material layer thickness measuring ultrasonic sensor 16a (total sintering raw material layer thickness 11) is larger than the sintering raw material layer thickness set value X. Occurs. Therefore, as shown in the above equation (1), at the same time as the integral signal b increases, the influence of the increase of the integral signal b is taken in as γ · b and reflected on the manipulated variable signal c of the sintering raw material layer thickness control system A. . That is, in this case, γ · b is the manipulated variable signal c
In the direction of decreasing the total thickness 11 of the sintering raw material. Conversely, the measurement value (coarse-grained raw material mountain slope thickness 12) measured by the coarse-grained raw material mountain slope thickness measuring ultrasonic sensor 16b is larger than the coarse-grained raw material mountain slope thickness setting value Y, and the raw material cutting gate 3 When the integral signal b changes in the decreasing direction, γ · b acts in the opposite direction, acts in the direction to increase the manipulated variable signal c, and causes disturbance that acts to decrease the total thickness 11 of the sintering raw material. Play the role of restraint.

Similarly, in the case of the equation (2), when the measurement value (the total thickness 11 of the sintering raw material) measured by the sintering raw material layer thickness measuring ultrasonic sensor 16a is smaller than the sintering raw material layer thickness set value X. The direction in which the amount of gas blown from the gas blowing nozzle 3 increases, that is, the integral signal a changes in the direction in which it increases. As a result, since the amount of the coarse-grained sintering raw material 19 that does not fall from the opening 4 and slides down on the downstream-side charging chute 7L as it is is reduced, the coarse-grained raw material mountain slope 12 on the sintering pallet 10 is also reduced. . This is the coarse-grained raw material mountain slope thickness control system B.
And the measured value (the coarse-grained raw material mountain slope thickness 12) of the raw material mountain slope thickness measuring ultrasonic sensor 16b is smaller than the coarse raw material mountain slope thickness set value Y. Therefore, the integration signal a increases and the integration signal a
Is taken as δ · a and is reflected on the manipulated variable signal d of the coarse-grained raw material mountain slope control system B. In other words, in this case, δ · a acts in the direction of increasing the manipulated variable signal d, and plays a role of suppressing disturbance that reduces the coarse-grained raw material mountain slope 12. Conversely, the measured value of the sintering material layer thickness is larger than the sintering material layer thickness set value X, and the integrated signal a
Changes in the decreasing direction, δ · a becomes the manipulated variable signal d.
And acts to reduce the
Plays a role in suppressing the increased disturbance.

As described above, in the above equations (1) and (2), the respective straight integrated values α · a and β · b
Indicates the basic operation amounts of the respective control systems of the sintering raw material layer thickness control system A and the coarse-grained raw material mountain slope surface thickness control system B,
Each of the cross integrated values γ · b and δ · a has a role of suppressing the influence of interference from the other control system. In other words, by adjusting each control system straight integration coefficient α, β and cross integration coefficient γ, δ to appropriate values, the influence of mutual interference between the two control systems is suppressed, and the sintering raw material layer thickness control system A and the coarse It is possible to keep the two control systems of the granular material mountain inclined surface thickness control system B in a stable control state. As shown by the dotted line in FIG. 1, a second gas blowing nozzle 15L is provided below the downstream charging chute 7L of the fine / fine-grained sintering raw material 18 falling from the opening 4, and gas is supplied from the nozzle 15L. The sintering pallet 10 is sprayed in a parallel direction, the falling fine / fine grain sintering raw material 18 is classified into fine / fine grains, and the fine sintering raw material is deposited on the upper layer of the coarse sintering raw material layer. It is preferable to deposit fine sintering raw materials.

[0015]

According to the present invention, the sintering raw material layer thickness control system and the raw material mountain slope surface thickness control (sintering raw material mountain thickness) control system can be maintained in a stable control state without mutual interference. It has become possible to keep the density distribution in the width direction of the sintering pallet of the sintering raw material in a good state while keeping the sintering raw material layer thickness constant. As a result, the yield and strength of the sintered ore are improved, and the effect in this field is great.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a raw material charging apparatus to which a charging method of a raw material for sintering according to an embodiment of the present invention is applied.

FIG. 2 is an explanatory diagram of a conventional technique.

FIG. 3 is an explanatory diagram of a conventional technique.

FIG. 4 is an explanatory diagram of a non-interference calculation device of a raw material charging apparatus to which a method for controlling charging of a sintering raw material according to an embodiment of the present invention is applied.

[Explanation of symbols]

A: Sintering material layer thickness control system, B: Coarse grain material mountain slope thickness control system, X: Sintering material layer thickness setting value, Y: Coarse grain material mountain slope setting value, a: Sintering material layer Integral signal calculated by the proportional integral controller of the thickness control system, b: integrated signal calculated by the proportional integral controller of the coarse material raw material mountain slope control system, c: gas flow control valve Operation amount signal of drive unit,
d: raw material cutout gate drive unit operation amount signal, α: sintering raw material layer thickness control system straight integration coefficient, β: coarse grain raw material mountain slope thickness control system straight integration coefficient, γ: sintering raw material layer thickness control system cloth Integration coefficient, δ: Cross integration coefficient for coarse material mountain slope inclined surface control system, 1: Hopper, 2: Drum feeder, 3: Raw material cutout gate, 4: Opening, 6: Cut gate, 7: Charging chute, 7a: Charging chute, 7U: upstream charging chute, 7L: downstream charging chute, 10:
Sintering pallet, 11: thickness of sintering material layer, 12: thickness of coarse material hill, 13U: upper layer of sintering material layer, 13L: lower layer of sintering material layer, 14: drop position, 15U: first gas blowing Attaching nozzle, 15L: second gas blowing nozzle, 16: ultrasonic sensor, 16a: ultrasonic sensor for measuring thickness of sintering raw material layer, 16b: ultrasonic sensor for measuring thickness of raw material mountain inclined surface, 1
7: sintering raw material, 18: fine / fine-grained sintering raw material, 19: coarse-grained sintering raw material, 20: coarse-grained raw material pile, 22: control circuit, 22a:
Sintering material layer thickness control system proportional integral controller, 22b: coarse grain material mountain slope surface thickness control system proportional integral controller, 23: non-interference operation device, 24: ignition furnace, 25: gas supply pipe, 26: gas flow rate Control valve, 26a: gas flow control valve drive, 27: raw material cutout gate drive

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F27B 21/14 F27B 21/14 BF Term (Reference) 4K001 AA10 BA02 CA35 CA41 GA10 GB11 HA01 4K050 AA04 BA02 CA07 CF07 CF09 CF10 CG08 CG29 EA03 EA04

Claims (1)

[Claims] 1. When sintering raw material in a hopper is cut out by a drum feeder and a raw material cutout gate and charged on a sintering pallet via a charging chute, sintering is performed on the sintering pallet from the charging chute. The thickness of the sintering raw material pile formed on the sintering pallet at the time of charging the raw material is measured, a deviation between the measured value and a preset value is obtained, and the deviation is further calculated by a proportional integral calculation. A sintering material thickness control system for controlling the sintering material thickness by manipulating the degree of opening of the material cutout gate based on the proportional integral operation value, and providing an opening in the middle of the charging chute; A gas blowing nozzle for blowing gas toward the sintering raw material sliding down on the charging chute is provided above the sintering pallet, which is determined by the amount of fine and fine sintering raw material falling from the opening. Measuring the thickness of the sintering material layer deposited on the
Calculating a deviation between the measured value and a preset value, and further operating a gas blowing amount from the gas blowing nozzle based on a deviation proportional integral calculation value obtained by performing a proportional integral calculation of the deviation. In the control method of the sintering raw material charging apparatus having a sintering raw material layer thickness control system to control the sintering raw material layer thickness by setting a straight integration coefficient and a cross integration coefficient for each control system in advance, The straight integral value of the one control system is integrated with the deviation integral integral value of one control system to obtain a straight integral value, and the cross integral of the one control system is calculated by the deviation proportional integral integral value of the other control system. It is characterized in that a cross integrated value obtained by integrating the coefficients is obtained, a control amount of the operation unit of each control system is determined from the obtained straight integrated value and the cross integrated value, and control of each control system is performed. Charging control method of sintering material to.