KR100418978B1 - Layer injection method for preventing complex layer to radial direction in blast furnace - Google Patents

Abstract

The present invention relates to a layered charging method for preventing mixed layer formation in radial direction in a Beles blast furnace. The rotation speed was increased to minimize the coke collapse caused by the coke, and the ferros is a charging method that suppresses the formation of the mixed layer by reducing the rotation speed at the first notch. In order to improve the gas flow and air permeability stable radially by preventing the formation of a mixed layer of coke and ferros by reducing the length and keeping the terrace long.

The present invention solves the change in fuel and raw material conditions, the control of the charge distribution, and the gas flow and breathability inside the blast furnace smoothly and optimally by charging the coke to spread the ferros and the sumool so as not to overlap. It will contribute to the improvement of charter quality as well as the blast furnace productivity and long life.

Description

LAYER INJECTION METHOD FOR PREVENTING COMPLEX LAYER TO RADIAL DIRECTION IN BLAST FURNACE}

The present invention is to charge the coke to spread evenly from the periphery to the center in charging the charge (ore and coke) in the Belle blast furnace, and to charge the sintered or small sintered ore so as not to form a mixed layer on the radial direction in the furnace The present invention relates to a layered charging method for preventing mixed layer formation in radial directions in a Beles blast furnace, which makes it possible to improve the breathability of the soft fusion layer and to maintain the blast furnace blasting by making the layer of each star uniform.

The blast furnace operation, as shown in Figure 1, by charging the iron ore and coke layered by using the top loading equipment and by the chemical reaction of the coke and iron ore of the preheating stage 113, the reducing zone 114, the drip tray 115 During the stage, molten iron and slag are produced from iron ore and descended to the lower part through soft fusion slit, and when a certain amount is gathered, it is discharged to the outside of the blast furnace through the exit port.

The operation of the furnace is economical only when the soft and raw material distribution in the furnace is stable, iron ore is reduced and melted under good conditions of the overall flow of gas, and the molten iron collected at the bottom of the furnace is discharged to the outside of the furnace. At the same time, productivity and blast furnace life will be improved.

In recent years, the operation of the blast furnace is a competitive index of the blast furnace depending on what is economically charged as the alternative fuel for coke, and in many blast furnaces in the world, crushing relatively inexpensive coal instead of coke, an expensive fuel, for economic operation. The pulverized coal is directly injected into the blast furnace 14, and it is trying to inject a large amount of pulverized coal competitively to reduce the cost of the molten iron manufacturing.

The increase in the pulverized coal injection ratio means an increase in the amount of ore charged in the furnace, which reduces the amount of coke in the blast furnace and blocks the passage of reducing gas in the softening zone, as well as fluctuations in furnace heat due to the lower core coke. Will result.

In the normal blast furnace operation, if the ventilation resistance inside the blast furnace is increased, if the internal condition of the furnace (hereinafter referred to as 'yellow') becomes unstable, the amount of coking charged in the furnace is increased by increasing the amount of coke charged in the furnace. In order to secure the passage of reducing gas and to adjust the length of the coke terrace, the shape of the contents of the furnace is changed, but as the life of the blast furnace is extended, there is a non-uniformity with the furnace lead and an inert zone of the furnace stop. Because of the damage to the furnace smoke, the blast furnace should be rested for 2 to 3 days and the furnace wall should be regenerated, so a layered charging method is required to prevent the formation of a mixed layer.

For example, as shown in FIG. 2, although a layer loading method is disclosed in which a mixed layer is not formed in a radial direction, such a layer loading method firstly notches coke 2 and ferros (= elastic iron ore) 23. It is very difficult to control the center temperature as it is spread evenly from the last notch. The control of the center temperature depends on the amount of coke and the last notch of the sintered ore. Skew and distortion of the fusion layer is frequently used because it causes a change in the yellowing is currently rarely used.

Therefore, in the blast furnace aiming to increase the pulverized coal injection cost, the amount of coke charged into the furnace is small, and when ferros is charged into the coke terrace tip, the large portion of ferros breaks down the coke slope and so much coke flows into the center. As a result, the ore ratio in the radial direction is not constant and the gas flow in the furnace is uneven.

In particular, the ore ratio of notched overlapping ferro-coke is relatively high, so the softening zone cannot secure the minimum coke layer through which reducing gas can pass, so the temperature difference between the periphery, middle and center is high and the ore ratio is high. In the case of less reaction of the charges and reducing gas, the unreduced ore falls into the tuyere, resulting in unstable operation such as fluctuations in the furnace, resulting in lower productivity and lower lifetime.

The present invention is to solve the above problems, by setting a certain amount of coke to the layer from the periphery to the center to set the number of rotations for each notch so that the mixed layer is not formed and the ferro intermediate on it It spreads from the central part to the central part and charges the sumool from the peripheral part to the middle part so that the notches of the ore and the coke do not overlap, thereby maintaining the ore ratio by the radial direction in the furnace to ensure breathability in the soft fusion layer and to stabilize the inside of the furnace. Its purpose is to maintain the stabilization of old age by gas flow.

In order to achieve the above object, the present invention is calculated so that the charge amount of each notch from 1 notch to 10 notches according to the coke 1 charge charge amount can be charged evenly according to the set number of revolutions and the value is calculated. Applying a flow characteristic of coke on the basis of the first step of automatically calculating ore flow control adjustment angle according to the rotation speed and transmitting it to the trip PLC; In the above step, after the charging is completed, the display unit displays on the process computer so that the operator knows the charging amount of each notch, and if the deviation is determined by determining whether the charging amount of each notch is equal to the value calculated in step 1, (2) feeding back to be compensated in (Charge); Calculate the charging amount of each notch from the first charging notch selected in the matrix to 10 notches according to the Phero's primary charge amount, and make the number of revolutions by applying the flow characteristics of the ferros based on the value. Three steps of automatically calculating the ore flow control control valve angle according to the transfer to the top PLC; In the above step, the display unit displays on the process computer so that the operator knows the charge amount of each notch after the completion of the charge and the charge amount of each notch is determined to be equal to the value calculated in step 3. 4 steps of feeding back to be compensated; According to the sum of the charge of the sumo, the notation of the ferro-loading notch does not overlap from the 1st notch to the notch before the first loading of the ferros, and the charging amount of each notch is calculated to be equally charged according to the set rotation speed, and based on the value 5 steps of automatically calculating the ore flow control adjustment angle according to the number of revolutions by applying the flow characteristics of the ool and transmitting it to the top PLC; In the above step, the display unit displays on the process computer so that the operator knows the charge amount of each notch after the completion of the charge and the charge amount of each notch is determined to be equal to the value calculated in step 5. Provided a layer loading method for preventing radial mixed layer formation in the Beles blast furnace comprising a six step of feedback to be compensated.

1 is a charging flow diagram of a typical blast furnace,

Figure 2 is a schematic diagram of a conventional charge distribution control shape,

Figure 3 is a schematic diagram of the charge distribution control shape according to the present invention,

Figure 4a is a drop trajectory and angle and loading matrix for each notch according to the prior art,

Figure 4b is a drop trajectory and angle and loading matrix for each notch according to the present invention,

5 is a graph showing changes in the central temperature and the upper probe temperature in the blast furnace according to the present invention.

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

113: preheating zone, 114: reduction zone,

115: The enemy ships.

Hereinafter, it will be described in detail on the basis of the drawings and equations attached to the present invention.

In the blast furnace operation, as shown in FIG. 1, when the coke and the sintered ore discharged from the top hopper 16 become 1.0 m in the normal operation, the turning chute 11 rotates at a constant speed, and rotates forward and reverse. Charged to form a layer.

When the coke is burned by blowing hot coke through the tuyere 14, a heat source and a reducing gas are generated, and the iron ore is reduced and melted by the heat source and the reducing gas, and finally, a melt is present below the softened fusion zone. .

In order for such melt reduction to occur effectively, the flow of reducing gas must be smooth. Especially, when the first charge is made at the top of the blast furnace charge, the layer thickness must be charged in the radial direction of the blast furnace so that the permeability of the peripheral part, the middle part and the center part is stable, and the nodular fluidity It is stable.

Therefore, in the present invention, when the ore ratio is determined according to the amount of pulverized coal and the total ore amount is determined, each notch is determined from each notch to 10 notches according to the amount of coke charge (CHARGE) excluding the core coke amount and the intermediate coke amount in the process computer. In order to make the charging amount evenly charged according to the rotation speed set in the notch matrix, the charging amount of each notch is automatically calculated based on Equation 1 below based on the total rotation speed and the rotation speed of each notch.

[Equation 1]

Quantity of charge by each notch = (total amount of charge / total number of revolutions) × number of revolutions by notch

Based on the value, the coke flow rate characteristic (experimental value has a coke 0.01 and a flow rate constant constant of 0.03) is applied and the ore flow control adjustment angle is automatically calculated by the following equation (2) Coke is charged by passing it to the system and to the traveling weighing system.

[Equation 2]

Opening degree of control valve = ⓐ × constant,

Ⓐ (Flow control control angle) = {Coke's total charge (Peros) / (Total revolutions × 1 turn)}-{Modified coke's total charge (Peros) / (Total revolutions × 1 turn)}

Subsequently, after the coke has been charged, the amount of charge for each notch, the target flow control valve angle, the primary charge amount, and the total charge time are displayed on the process computer so that the operator can know the charge amount for each notch equal to the value calculated in [Equation 1]. In the case of deviation, the ore flow control valve angle is calculated based on [Equation 2] to be compensated for the next charge.

Automatically calculate the charging amount of each notch based on the total rotation speed and the rotation speed of each notch so that the charging amount of each notch from the first charging notch selected in the matrix to 10 notches can be charged uniformly according to the Faros primary charge amount [Equation 1] Based on the value, the Peros flow characteristics (Table 2) are applied and the ore flow control adjustment angle is automatically calculated and transferred to the Pt.

After the loading of the ferrosion, the notch charge amount, target flow control angle, primary charge amount, and total charge time are displayed on the process computer so that the operator can know the display unit and the charge amount for each notch. If the difference is determined by comparing the deviation, the ore flow control valve angle is calculated based on [Equation 2] to be compensated for the next charge.

According to the charging amount of the sumo (= small iron ore), the ferro and charge notches do not overlap from the 1st notch to the notch before the first loading of the ferros, and the charge amount of each notch is automatically calculated based on the total rotation speed and the rotation speed of each notch. Equation 1] and automatically calculates the ore flow control control valve angle based on the value and transfers it to the stationary PLC and the notch weighing system to charge the sumool.After the sumo load is completed, the loading amount of each notch, the target flow control valve angle, Display the primary charge amount and the total charge time on the process computer so that the operator can know and compare and judge whether the charge amount of each notch is equal to the value calculated in [Equation 1] so that the deviation can be compensated for the next charge in case of deviation. Based on Equation 2, the ore flow control valve angle is calculated and becomes the next charge sumo flow control valve angle setting value.

More specifically, as shown in FIG. 3, by reducing the inclination angle of the coke 27 and the ferro 28 without forming the coke terrace, the inflow of the charges is suppressed so that the thickness of each layer is fixed from the top of the charge. By maintaining the flow rate, the flow of gas is kept uniform and the gas utilization rate is increased.

In addition, as illustrated in FIGS. 4A and 4B, the number of revolutions of the coke is reduced in the periphery where the sumool is to be loaded, thereby adjusting the overall thickness of the charge and controlling the sumo temperature for controlling the upper body temperature essential for normal operation. And increase and decrease the amount of use of smoke and the amount of coke that overlaps with the sumo.

Therefore, conventionally, the furnace center temperature control is controlled by the coke and the sintered amount of light charged in the last notch by using the ore flow control valve by layer loading without the central coke charging method, but in the present invention, the central temperature control is the central coke amount. It is possible to secure stable central temperature by preventing the inflow of ferrosion due to the inclination angle of the coke by controlling the amount of coke in the center.

In addition, due to the difference in coke and ferros specific gravity and the difference in drop energy, a mixed layer is formed at the time of ferros loading after the coke is charged, and the portion thereof has a high ore ratio. By charging, it controls to settle softly without collapsing the existing coke.

In addition, the conventional coke and ferros are charged evenly from the first notch to the last notch, but in the present invention, by separately charging small particles and oppositions, it is possible to smoothly control the furnace temperature, which is essential for normal operation, and in particular, the amount of each notch is charged. Can be controlled using the ore flow control valve.

In the present invention, as shown in FIG. 5, the charge and the upper probe (Upper Probe) temperature of the charge is kept constant in the radial direction, and the coke and the ferros are evenly loaded without overlapping parts and the ferros and the smoke overlaps the part It is charged while removing and keeping the layer of each type constant in the radial direction.

As described above, the present invention provides a formula that can calculate the charge amount of each notch for the charge amount of each type so as to keep the charge stratification in the radial direction in the furnace as compared to the conventional method, and after charging the coke spread and ferro This solution solves the problems of changes in fuel and raw materials and control of the load distribution by charging the sumo and sumo so as not to overlap, and keeps the gas flow and air permeability inside the blast furnace at an optimal level at all times to improve the charter quality as well as blast furnace productivity and long life. It will greatly contribute to the painting.

Claims (1)

Calculate the amount of charge for each notch from 1 notch to 10 notches according to the coke 1 charge charge amount and load it evenly according to the set number of revolutions. A step of automatically calculating the side angles and transmitting them to the stationary PLC; In the above step, after the charging is completed, the display unit displays the charge amount of each notch on the process computer so that the operator can know and the charge amount of each notch is equal to the value calculated in the first step. 2 steps to give feedback; Calculate the charging amount of each notch from the first charging notch selected in the matrix to 10 notches according to the Phero's primary charge, and apply the flow characteristics of the ferros based on the value. Three steps of automatically calculating the ore flow control control valve angle according to the transfer to the top PLC; In the above step, the display unit displays on the process computer so that the operator knows the charge amount of each notch after the completion of the charge, and it is determined whether the charge amount of each notch is equal to the value calculated in step 3. 4 steps of feedback; According to the sum of the charge of the sumo, the notation of the ferro-loading notch does not overlap from the 1st notch to the notch before the first loading of the ferros, and the charging amount of each notch is calculated to be equally charged according to the set rotation speed, and based on the value 5 steps of automatically calculating the ore flow control adjustment angle according to the number of revolutions by applying the flow characteristics of the ool and transmitting it to the top PLC; In the above step, after the charging is completed, the display unit displays the charging amount of each notch on the process computer so that the operator can know and the charging amount of each notch is equal to the value calculated in step 5. Layer loading method for preventing radial mixed layer formation in the Beles blast furnace is configured to include a six-step feedback.