KR100762455B1 - Method for charging large ore into blast furnace to control co gas coefficient?co of utilization - Google Patents

Abstract

The present invention relates to a method of charging and receiving the opposing light in the allele for controlling the CO GAS utilization rate (ηCO), and more particularly, to optimize the CO GAS utilization rate (ηCO) based on the seismic digit (I) of the allele charged in the furnace. The present invention relates to a method of charging an opposing or external dust for controlling CO GAS utilization rate (ηCO) for management.

To this end, the present invention, when the calculated allergic seismic seismic index (I) is less than the appropriate management index by the telecommunications controller 80 by the number of revolutions of the notched light on the charging matrix (50) in the blast furnace center direction , Increase the number of rotations toward the furnace wall, enter the load, and set the charge so that the allergic seismic index (I) reaches an appropriate range, while the calculated allelic seismic index (I) may increase from the appropriate management index. In this case, the electric communication controller 80 inputs the rotational speed of the opposed light notches on the charging matrix 50 by increasing the rotational speed in the blast furnace wall direction, decreasing the rotational speed in the center direction, and the anti-optical seismic index ( Set charging so that I) reaches the appropriate range.

As described above, the method of charging and recharging the opposing ore dust for controlling the CO gas utilization rate (ηCO) according to the present invention minimizes the heat discharged by controlling the residence time of the reducing gas generated in the combustion process of the fuel and the raw materials charged in the furnace. By effectively maintaining the thermal efficiency of the hot stove to maintain a constant hot wind temperature inside the blast furnace has the effect of operating the lowest fuel costs in the operation of high draw ratio.

Blast furnace, allele seismic index, CO GAS utilization rate, charging matrix, turning suit

Description

METHODS FOR CHARGING LARGE ORE INTO BLAST FURNACE TO CONTROL CO GAS COEFFICIENT (ηCO) OF UTILIZATION}

1 is a schematic diagram showing a general blast furnace shape and the charge input path;

Figure 2a is a state diagram showing the drop trajectory and charging state according to the angle according to the notch of the blast furnace charge;

Figure 2b is a notch charging matrix diagram of the blast furnace charge according to the conventional charging method;

Figure 3 is a block diagram for a method for charging the opposite light in and out for the CO GAS utilization (ηCO) control according to the present invention;

4 is a flowchart of a method for charging an allergic light in and out of alleles for controlling CO GAS utilization (ηCO) according to the present invention;

FIG. 5 is a notch charging matrix diagram of the blast furnace charges charged according to the method of charging and receiving the opposing light source for controlling CO GAS utilization rate ηCO according to the present invention; FIG.

6 is a graph showing the upper temperature of the blast furnace charge charged according to the conventional charging method;

7 is a graph showing the upper temperature of the blast furnace charge charged in accordance with the method for charging and receiving the opposing light for the CO GAS utilization (ηCO) according to the present invention.                 

♣ Explanation of symbols for main part of drawing ♣

1: Blast furnace 2: Balloon 9: Turning suit 12: Coke 13: Opposition light 14: Small particle light

15: center coke 21: computer for calculating the seismic index of the opposing light 26: electric signal controller

29: Trip PLC 29: Trip gas analyzer 34: Alternative seismic index 35: Charging matrix

The present invention relates to a method of charging and receiving alleles in and out of alleles for controlling CO GAS utilization rate (ηCO). More specifically, the present invention relates to CO GAS utilization rate (ηCO) based on the seismic number (I) of the alleles charged in a blast furnace. ) To optimally manage the COGAS utilization rate (ηCO) to control the residence time of fuel and raw materials, auxiliary fuel (pulverized coal) and reducing gas generated during the combustion of hot air It is about charging method.

In general, the blast furnace operation, as shown in Figs. 1 to 2, charging iron ore and coke first charge (coke 12, opposing light 13) using a turning chute 9, which is a top charging device. , Small particle 14] advances by a certain angle (60 °) and charges the coke 12 so that the terrace is maintained at 1.0 to 1.2 m while being forward and reversed at every sixth charge. Then, the opposing light 13 is charged thereon so that the mixed layer is formed by the load of the charge, and the gas flow in the middle part and the central part of the blast furnace 1 is controlled by the radial direction of the blast furnace (1). The small particle 14 is charged for skin flow control so that the distribution of the charged matter in the circumferential direction is kept constant.
1 and 2, reference numeral 4 denotes a 'outlet', 5 denotes a 'loading stand', 7 denotes a 'preheater', 8 denotes 'the upper part of the load', 10 denotes a 'loading hopper', 12 'Coke bean', '13' for 'opposite bean', and '14' for 'small particle bin'.

In addition, by inserting the central coke 15 into the center of the furnace, the flow of gas in the furnace is generally activated to prevent the wear of the blast furnace 1 in the furnace wall part by activating the central flow and suppressing the furnace wall. Central flow activation operation is carried out to suppress and dissipate heat.

To explain this in detail, as shown in the drop trajectory and the charging matrix diagram shown in Figs. 2A to 2B, the charging method of the blast furnace is loaded in the blast furnace 1 according to the angle 18 of each notch 17 of the swing chute 9. In the radial direction of the blast furnace (1), the central coke (15) having the highest air permeability among the charges in the center of the blast furnace, and the coke (12) and the opposing light (opposite sintered ore) Charged grained light + subsidiary material) 13 is charged to guide the mixed layer 16, and charged to the furnace wall side is a small-air light (small sintered ore) 14, the most breathable.

As shown in FIG. 1, the charge loaded with the layered layer is molten iron and slag (melt) from iron ore while undergoing preheating, reduction, and dropping by a chemical reaction of hot air gas and iron ore supplied from the tuyere 2. (3) is generated and the softening fusion table (6) is lowered to the lower part through the slits, and when a certain amount is gathered, it is discharged to the outside of the blast furnace (1) through the exit port (4). Alternately and continuously.

In addition, the blast furnace by-product gas (hereinafter referred to as BFG) generated in the direct or indirect reduction process is a main component of BFG, which is regenerated as combustion gas of a hot blast furnace for supplying hot air of blast furnace, such as nitrogen (N 2), carbon monoxide (CO), and carbon dioxide ( CO2) and hydrogen (H2) are divided into two. CO and CO2 are the main factors that determine the CO GAS utilization rate (ηCO).

The formula for calculating the CO GAS utilization rate (ηCO) is as follows.

The optimum management range of the above-mentioned CO GAS utilization rate (ηCO) is 50 to 52%. However, the CO GAS, which is unreduced gas due to the rapid discharge of reducing gas by activation of the central flow due to the ingress of the opposing dust (direction toward the furnace side), This results in an increase in the CO GAS utilization (ηCO) that is significantly reduced.

In addition, the operation of blast furnaces is a relatively low cost alternative to coke, which is an expensive fuel for economical operation in many furnaces in the world, as the blast furnace operation is used as an index of competitiveness of the furnace depending on how economically the coke is replaced. The pulverized coal produced by crushing is directly injected into the blast furnace blast furnace, and it is trying to inject a large amount of pulverized coal competitively in order to reduce the cost of charter manufacturing.

The increase in the pulverized coal injection cost means an increase in the amount of ore charged in the furnace, and the center of the center of the blast furnace to secure the flow path of the GAS due to the thinning of the coke layer due to the decrease of the coke charge in the blast furnace. I charge coke.

However, the charging of the core coke as described above increases the discharge rate of GAS to the center, and the length of the upper part of the charge is gradually shortened by the rise of the center of the softening fusion zone, which shortens the reaction time between the reducing gas and the charge. As a result, the reduction with the charge and the preheating time are shortened.

Therefore, it leads to an increase in CO GAS among the components of blast furnace gas (BFG) discharged from the furnace, resulting in a decrease in E-CO (CO GAS utilization) and converting E-CO (CO GAS utilization) into fuel costs. When the utilization rate (ηCO) decreases by 1%, the fuel rises by 5 kg per ton of molten iron, and the blast furnace pressure increases due to the shortening of the discharge time due to the decrease in temperature of the melt due to the decrease in temperature of the furnace part due to the lowering of the furnace. It will lead to a decrease in production due to long-term yellowing relief due to a slowed production rate.

In addition, when the CO GAS utilization rate (ηCO) is increased (greater than 52%), the thermal efficiency of BFG, which is used as a heat source of the hot blast furnace, decreases due to the increase of the CO2 ratio in the blast furnace gas (BFG). In addition to causing a decrease in the blowing temperature, the absence of a quantitative operation index for adjusting the CO GAS utilization rate (ηCO) of the BFG to the appropriate management range as described above, causing a time loss for adjustment to the management range.

Accordingly, the present invention has been made to solve the above problems, fuel and raw materials charged in the furnace by optimally managing the CO GAS utilization (ηCO) based on the seismic digit (I) of the alleles charged in the furnace. And control the residence time of reducing gas generated during combustion of auxiliary fuel (pulverized coal) and hot air to minimize the heat released with reducing gas so that the operator can optimally manage the heat of the operation The purpose of this study is to provide a method for charging and receiving alleles for CO GAS utilization (ηCO) control in the Belles blast furnace.

In order to achieve the above object, the method for charging the opposing light in or out of dust for controlling CO gas utilization rate (ηCO) according to the present invention includes a monitor installed so that an operator can check the CO gas utilization rate (ηCO), An electric signal controller for controlling an electric signal, and an instrumentation signal controller connected to a gas analyzer 34 to control an instrumentation signal, and a PLC to a station PLC. Making a step;

The ratio of CO2 to CO is calculated using the CO GAS utilization rate (ηCO) equation. The CO GAS utilization rate (ηCO) calculated by the process computer for calculating the allele seismic index is calculated using the CO GAS utilization rate (ηCO) equation. Displaying on the monitor;

Calculating, by the process computer for calculating the allergic seismic index, an allelic seismic index (I) by using an allergic seismic index calculation equation on the rotational speed of the notch in the charging matrix according to an allelic seismic index calculation formula;

If it reduced more management index preset on the basis of the calculated opposing light seismic index (I) to increase the number of revolutions the allele number of optical rotation by the notches on the charged matrix by an electrical signal from the telecommunication controller into the blast furnace center direction, Reducing the number of rotations to the furnace wall side and inputting, and setting charging so that the allergic seismic index I reaches a range of a predetermined management index ;

When the calculated allied seismic seismic index (I) is greater than a predetermined management index range , the rotational speed is increased in the furnace wall direction by the rotational speed of the notched light on the charging matrix according to the electric signal of the telecommunications controller. Enter and decrease the rotational speed in the direction, and set the charging so that the allergic seismic index (I) reaches a preset management index range. By controlling the flow of reducing gas in the furnace through the method to maintain a constant top temperature of the furnace charges to facilitate the distribution of gas flow in the furnace.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a block diagram for the method for charging the opposing light in and out for the CO GAS utilization rate (ηCO) according to the present invention, Figure 4 is a method for charging the opposing light for the CO GAS utilization rate (ηCO) according to the present invention. Is a flowchart of.

In the alternative method for charging and receiving the opposing light for controlling the CO GAS utilization rate ηCO according to the present invention configured as shown in FIGS. 3 to 4, a monitor 20 is installed so that an operator can check the CO GAS utilization rate ηCO. It is connected to a process computer 21 for calculating the allergic seismic index, and the process computer 21 for calculating the allergic seismic index is a CO GAS utilization calculation means 30 and an allergic seismic index calculation means 31. It is connected to the setting input unit 23, the seismic index setting input unit 24, the seismic index calculation input unit 25 of the charging matrix, and an electric signal controller (Electric Communication Controller) 26 and the blast furnace for electric signal control (1) Instrument communication controllers (28) for controlling the instrumentation signal of the gas detector 27 for gas component detection in each are installed and connected to the programmable PLC (29). .

As shown in FIG. 4, a process computer for calculating a CO GAS utilization rate ηCO using a CO GAS utilization rate equation ηCO as a ratio of CO2 and CO through a gas analysis result of the gas gas analyzer 27. (21) is calculated and displayed on the monitor (31).

5 is a charging matrix diagram of a blast furnace charge charged according to an allergic or external dust charging method for controlling CO GAS utilization rate ηCO according to the present invention.

As shown in FIG. 5, an allergic seismic index 34 calculated according to the rotational angle 19 ′ of the allergic notch 17 on the charging matrix is displayed on the charging matrix, and the allergic seismic index is displayed. On the basis of this, the internal and external earthquake calculation part 32 which calculates the rotation speed for each notch and the charging setting part 33 to charge are comprised.

By the method as described above, when the calculated allergic seismic seismic index (I) is lower than the predetermined management index range by the electric signal of the electric signal controller 26 by the notch by the opposing light notch on the charging matrix 35 ( 17) The rotation speed 19 'is inputted by increasing the rotation speed toward the center of the blast furnace, decreasing the rotation speed toward the furnace wall, and setting the charging so that the opposing light seismic index I reaches the preset management index range. Steps;

On the basis of the calculated allied seismic index (I), if the increase is greater than the appropriate management index, the number of revolutions (19) by the notch (17) on the charging matrix 35 by the electric signal of the electric signal controller 26 ) Is inputted by increasing the number of revolutions in the furnace wall direction, decreasing the number of revolutions in the center direction, and setting the charging so that the anti-optic seismic index (I) reaches an appropriate range. An allelic input / external charging method for (ηCO) control is executed.

Hereinafter, a preferred embodiment of the present invention will be described in detail.

EXAMPLE

In general, in a large blast furnace having an internal content of 3800 Nm 3 or more, as illustrated in FIG. 1, an air blowing amount of 6000 N m 3 / min is blown through the air vent 2 at a temperature of about 1150 to 1200 ° C. at a flow rate of about 220 m / sec.

The hot air blown into the blast furnace (1) is heated to 2200 ~ 2300 ℃ to react with oxygen, pulverized coal, coke blown with the hot air at the tip of the tuyere (2), and reacts with the fuel raw material charged in the blast furnace (1) Reduction gasification causes melting reaction with the raw materials in the softening fusion zone (6), while passing through the charge layer at a flow rate of 2 to 3 m / sec while being reduced and reacted and discharged to the gas pipe through the upper part of the charge, part of the blast furnace gas reservoir ( BFG Holder (not shown) and some are used as combustion gases in hot stoves.

At this time, the gas analyzer 27 installed in the gas pipe 36 is to sample the discharged BFG to continuously analyze the components to calculate the CO GAS utilization (ηCO) using CO and CO2 GAS in the blast furnace gas [Equation 1] The CO GAS utilization rate ηCO is displayed on the monitor 20 via the process computer 21.

On the other hand, through the [Equation 2] to obtain the allergic seismic index on the charging matrix input through the charging matrix setting input unit 23 of the electric signal controller 26, the allergic seismic index (I) to the charging matrix 35 Is displayed.

Equation 2 for obtaining the allele seismic index is explained in more detail, and the number of revolutions 19 'for each notch set in the charging matrix 35 is multiplied by the number of revolutions, and the sum of the notches is added. The value divided by the total number of revolutions is the seismic index, and the meaning of this value is a figure indicating how far the opposition ore is located on the furnace wall side or the center side.

In general, the notch of the charging light (Notch) is used to select the number of revolutions per notch while using up to 3 to 10 notches, taking into consideration the gas flow changes in the furnace, increase or decrease in CO GAS utilization rate, and the available charge rotational speed is expressed in equation (2). As a result of substitution, the seismic index is in the range of 4.5 to 6.5,

The CO GAS utilization rate (increased as the amount of gas generated in the furnace and increased gas residence time is increased) increases as the seismic index increases and the amount of charged opposing light toward the furnace center increases. As a result, the air resistance was increased by blocking the core part. On the contrary, when the seismic index was 4.5 or less, the opposing light was excessively charged into the wall to increase the furnace center temperature and increase the fuel cost. There was a positive correlation with gas utilization.

That is, as shown in the charging matrix 35 shown in FIG. 5, the charging notches of the opposing light are 4, 5, 6, 7, 8, and 9 notches, respectively, and the charging rotation speeds for each notch are 2, 2, In 2, 1, 1, 1 revolutions, the seismic index of the opposing light becomes 5.78 by Equation 2, wherein the CO GAS utilization rate is determined to be at an appropriate level in the 50% range.

Therefore, when the operator decides the charge rotational speed of each notch, the charge rotational speed 19 'by each notch 17 of the alternative light 13 to be used is determined based on the calculated value of the CO GAS utilization rate (ηCO). The seismic calculation 32 is executed on the charging matrix, and when the CO GAS utilization rate (ηCO) exceeds 52% based on Table 1, the number of rotations of the opposing light on the charging matrix is increased to the furnace wall side, and the confrontation of the furnace center is performed. When the light rotation speed is reduced and the allergic seismic index is calculated in the range of 5.8 to 6.2, the charging setting 54 is executed to determine the mounting rotation speed.                     

In addition, when the CO GAS utilization rate (ηCO) decreases to less than 50%, the number of rotations of the opposing light on the charging matrix 35 is reduced to the furnace wall side, and the number of rotations of the opposing light 13 at the center of the furnace is increased to perform the seismic calculation (32). When the allergic seismic index is calculated to be in the range of 5.8 to 6.2, the charging setting 33 can be executed to determine the mounting rotation speed 19 ', so that the CO GAS utilization rate 'To be in range.

In other words, the CO GAS utilization rate (ηCO) exceeded 52% during operation, and as a result of checking the notch and the rotation speed of the allele to change the notch of the allele in use, the results showed that 4, 5, 6, It was 7, 8, 9, 10 notches, and the charging rotation speed was 2, 2, 2, 1, 1, 1, 1 rotation. As a result of performing the seismic calculation 32 on the charging matrix 35 of FIG. 5, the seismic index of the opposing light was 6.40.

Input the charging speed so that the seismic index of the opposing light may be in the range of about 6, and when the seismic calculation (32) is performed, the charging notch satisfying the result value between the appropriate range of the seismic index of the opposing light (5.8-6.2) (17 ) And the number of revolutions 19 'are 2, 2, 2, 1, 1, 1 revolutions at 4, 5, 6, 7, 8, and 9 notches, respectively. Notch and rotation speed are changed and input. Until the result value is found, the seismic calculation 32 is performed two or three times.

By doing so, the charge amount of 10 notches on the furnace center side is eliminated, so that the amount of charge of the opposing light on the furnace center side decreases, and the amount of charge on the furnace wall increases relatively.

Conversely, if the CO GAS utilization rate (ηCO) is reduced to 50% or less, the seismic calculation (32) and the charge setting (33) are executed in the reverse order of the above procedure to satisfy the appropriate CO GAS utilization rate (ηCO) and seismicity index conditions. The charging notch 17 and the rotation speed 19 'of the opposing light can be obtained.

Figure 6 is a graph showing the upper temperature of the blast furnace charge charged according to the conventional charging method, Figure 7 is a blast furnace charge charged according to the opposing ore dust charging method for controlling CO GAS utilization (ηCO) according to the present invention. It is a graph showing the upper temperature.

As shown in Fig. 6 to 7, when the charge is charged to the blast furnace by the conventional charging method, the seismic index is out of the range of 5.8 to 6.2, the temperature of the center of the blast furnace is 600 ℃ or more, the CO GAS utilization rate (ηCO) is The thermal efficiency of the blast furnace gas (BFG), which is used as a heat source of the hot blast furnace, decreases to 47.2% to 48.9%, and the CO gas ratio decreases.

49.9 to 51.2% of the CO GAS utilization rate (ηCO) in the range of 5.8 to 6.2 seismic index controlled according to the method for charging the CO GAS utilization rate (ηCO) according to the present invention is about 500 ℃ Therefore, the conditions for reducing the thermal efficiency of the blast furnace gas (BFG), which is used as a heat source of the hot blast furnace, are satisfied due to sufficient reduction reaction conditions and a lower ratio of CO gas in the blast furnace.

As mentioned above, when the external seismic index rises to the furnace wall by increasing the seismic index, the flow of reducing gas passing through the blast furnace is accelerated, and the seismic index is lowered to the management range. If the seismic index of alleles decreases, the seismic index of the blast furnace is reduced by slightly reducing the air permeability to the center of the blast furnace through the seismic penetration of the opposing ore into the center of the blast furnace. To be in range.

The method for charging the allele into and out of the allele for controlling the CO GAS utilization rate (ηCO) according to the present invention is based on the seismic digit (I) of the allele charged in the furnace to optimally manage the CO GAS utilization rate (ηCO). By controlling the residence time of the fuel, raw materials, auxiliary fuel (pulverized coal), and reducing gas generated during the combustion of hot air, the heat discharged with the reducing gas is minimized, and the thermal efficiency of the hot blast furnace is effectively blown into the blast furnace. By maintaining a constant hot air temperature, the operator can manage the furnace optimally, and thus there is an effect that the lowest fuel cost operation can be performed in the high shipping cost operation.

Claims (2)

A monitor 20 installed so that an operator can check the CO GAS utilization rate ηCO, and the monitor 20 are connected to an allergic seismic index calculation computer 21, and the allergic seismic index calculation computer 21 Connecting an electric signal controller 26 for controlling an electric signal, an instrumentation signal controller 28 connected to the gas gas analyzer 27, and a PLC PLC 29 for controlling the instrumentation signal; The ratio of CO2 and CO obtained by the gas analysis result of the gas analyzer 27 connected to the instrumentation signal controller 28 is calculated using the CO GAS utilization rate (ηCO).

Displaying on the monitor 20 the CO GAS utilization rate? CO calculated by the process computer 21 for calculating the allergic seismic index by substituting for? The process for calculating the allergic seismic index is performed to calculate the number of revolutions 19 'of the allergic light 13 and the notches 17 on the charging matrix 35.

Calculating an allelic seismic index (I) by means of and displaying it on the monitor (20); When the calculated allergic seismic seismic index (I) is lower than a predetermined management index range , the number of revolutions of the opposing light (13) by notch (17) on the charging matrix (35) by the electric signal of the electric signal controller (26) (19 ') increasing the rotational speed toward the center of the blast furnace, reducing the rotational speed toward the furnace wall side, and setting charging so that the opposing light seismic index (I) reaches a range of a predetermined management index ; When not greater than the preset management index range based on the calculated allied seismic seismic index (I) by the electric signal of the electric signal controller 26, the opposing light 13 on the charging matrix (35) by notch (17) Inputting the rotation speed 19 'by increasing the rotation speed in the furnace wall direction, decreasing the rotation speed in the center direction, and setting the charging so that the anti-optic seismic index I reaches a preset management index range . Method for charging the opposing light in and out of the opposing light for CO GAS utilization (ηCO) control, characterized in that consisting of. The method of claim 1, The step of setting the charging so that the allergic seismic index (I) reaches a preset management index range includes the allelic seismic index (I) calculated so that the CO GAS utilization rate (ηCO) is 50 to 52%. And setting the charging to reach the opposite light in / out dust charging method for controlling CO GAS utilization rate (ηCO).

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