KR100419661B1 - Discharging method by alternation of burden distribution for shaft brick temperature control at blast furnace - Google Patents

Abstract

The present invention sets the charging mixture, the charging order and the charging amount of the lead / raw material to be charged according to the furnace wall temperature while sensing the furnace wall temperature during operation of the blast furnace, and when the furnace wall temperature rises, The charging method for controlling the furnace temperature of the blast furnace which can prevent the rise of the furnace heat load by controlling the temperature of the lower end of the furnace wall portion of the furnace body by controlling to charge the sintered ore,

The present invention relates to a method of controlling charging of fuel / raw material based on a temperature from a temperature sensor installed at a predetermined interval for each height in a furnace. After the charging is started, the furnace temperature is detected by detecting the furnace body temperature and the reference temperature. Comparing the first step; A second step of performing a normal charging according to a normal charging order and charging amount previously set for the lead / raw material including coke and the opposing sintered ore when the furnace temperature is lower than the reference temperature in the first step; In the first step, when the furnace temperature is higher than the reference temperature, the furnace temperature management mode is entered, and the basis weight of the lead / raw material is changed according to the charging order and the loading amount previously set for the lead / raw material including coke, allele sintered or small sintered ore. Performing a third step of transferring the basis weight of the fuel / raw material to the top hopper; When the basis weight of the small sintered ore reaches the predetermined target charge amount in the third step, the basis weight and the transfer process of the third step are repeatedly performed, and the basis weight value of the lead / raw material reaches the preset target charge amount. There is a fourth step to proceed to the next step; A fifth step of performing charging for each notch according to a charging order and charging amount previously set for the lead / raw material stored in the open hopper; After completing charging of the first patch in the fifth step, the sixth system proceeds to the first step.

Description

Charging method for furnace temperature control in blast furnaces {DISCHARGING METHOD BY ALTERNATION OF BURDEN DISTRIBUTION FOR SHAFT BRICK TEMPERATURE CONTROL AT BLAST FURNACE}

The present invention relates to a charging method of the blast furnace, in particular, in the operation of the blast furnace blast furnace ratio, by setting the charging mixture, the charging order and the charging amount of the lead / raw materials to be charged according to the furnace wall temperature while detecting the temperature of the furnace wall, A method of charging for furnace temperature control of a blast furnace which can prevent the rise of furnace heat load by controlling the temperature of the lower end portion of the furnace wall part of the furnace body to be controlled by charging the sintered ore into the furnace wall part when the wall temperature rises. will be.

In general, when the blast furnace is charged with iron ore and coke from the top of the blast furnace, and the hot air from the bottom of the blast furnace is blown through the tuyere, the iron ore is reduced and It is a process of melting and forming molten iron and slag. Recently, blast furnaces are gradually increasing the use of relatively inexpensive Pulverized Coal instead of expensive coke as iron ore reducing agent. Daily output per unit volume.

FIG. 1 is a flow chart of fuel / raw material loading in a general blast furnace. Referring to FIG. 1, the fuel / raw material charging process in a general blast furnace stores coke of a coke storage tank 1 in two coke hoppers through a basis weight and a transfer process. The sintered ore of the sintered ore storage tank 2 is stored in two sintered ore hoppers through a basis weight and a transfer process (via the belt conveyor 3, etc.), and the pellet is also stored in one storage hopper 4. Thereafter, the coke and the sintered ore of each storage hopper is supplied to the blast furnace hopper through a charging belt conveyor (5), and then the lead / raw materials stored in the hopper are charged into the blast furnace through a lower chute. .

As such, when carrying out the operation of the blast furnace, the temperature distribution in the blast furnace is generally lowered because the amount of charges in the blast furnace is relatively high, and the operation of flowing a large amount of gas into the center for stable operation (hereinafter referred to as 'center') In order to aim at the flow operation, the COKE layer, which is a passage through which gas flows from the furnace wall, becomes thinning operation (hereinafter referred to as O / C operation). For high O / C operation, a method of charging coke to opposing sintered ore is used. The charge drop trajectory when charging the lead / raw material is as shown in FIG. 8.

In the method of charging in the order of coke-to-opposite sintered ore, as shown in Fig. 3, for example, the charging amount of each notch is shown.

In addition, Figure 2 is a schematic diagram showing the blast furnace furnace wear erosion state, referring to Figure 2, the cooling plate (Cooling Plate) is inserted to cool the furnace yeonwa due to wear of the furnace yeonwa as the operating years of the blast furnace is elapsed Since it protrudes into the furnace, the distribution of the lead / raw material that is charged is not made as intended, but a mixed layer (coke and sintered ore) is formed, and thus, a central flow operation cannot be performed. As a result, as shown in FIG. A large amount of gas tends to flow (peripheral flow), which eventually raises the furnace heat load and, in severe cases, can cause large accidents in which the charges and semi-melts in the furnace explode out of the furnace due to breakage of the cooling plate. There is a problem that there is a risk.

This problem occurs in the lower portion of the body shaft 4 stage 20-1, the causes are as follows.

First, as a means to control the periphery in the blast furnace, the furnace wall is periodically repaired to repair the worn parts, but since the shaft is repairable only up to the level of 20 or more (20m from the charging level), the shaft is provided with four steps. Since 20-1 is not repaired, it is easy to generate a mixed layer, and thus, a periphery is easily generated and the furnace heat load is increased. Here, the furnace wall repair is performed by repairing the sprayed by circumferential direction by inserting a castable spray machine into the furnace by lowering the level of the charged contents to repair the worn ducts in the blast furnace. I say that.

Second, the operation to increase the O / C (Ore: COKE ratio) of the furnace wall can be carried out to suppress the surrounding flow, but in this case, there is a high possibility of wind and curve damage and there is a risk of secondary accidents. (Recently, 01.12.11 2BF No. 15 Punggu bend), there is still a problem that the mixed layer is still generated below the four-stage shaft.

The present invention has been made in order to solve the above problems, an object of the present invention is the charge mixture of the fuel / raw material to be charged according to the furnace wall temperature while sensing the temperature of the furnace wall during the operation of the furnace blast furnace ratio, charging order and charging amount By setting differently, the furnace wall temperature is controlled to charge the sintered ore into the furnace wall when the furnace wall temperature rises, so that the furnace temperature of the blast furnace can prevent the rise of the furnace heat load by managing the temperature of the lower end of the furnace wall in the proper range. It is to provide a charging method for the control.

1 is a flow chart of lead / raw material charging in a general blast furnace.

2 is a schematic diagram showing a blast furnace furnace wear erosion state.

Figure 3 is an illustration of the amount of charge for each notch in the conventional operation.

Figure 4 is a blast furnace radial load distribution and gas flow distribution graph in the prior operation.

5 is a block diagram of a charging system for controlling the furnace temperature for carrying out the present invention.

6 is a flowchart showing a charging procedure for controlling the furnace body temperature according to the present invention.

7 is a blast furnace furnace temperature sensor installation state diagram.

8 is a schematic diagram showing the blast furnace charge drop trajectory.

Figure 9 is an exemplary view of the charge amount for each notch of the charge when the furnace body temperature control according to the present invention.

10 is a blast furnace radial load distribution shape and gas flow distribution graph in the furnace temperature control according to the present invention.

11 is a graph showing the present invention and the conventional furnace temperature change trend.

Explanation of symbols on the main parts of the drawings

1: COKE storage bin 2: Sinter storage bin

3: small sintered ore weight basis belt conveyor 4: small sintered ore hopper

5: Belt Conveyor 10: Blast Furnace

10-1: Worst part of wear 20: Furnace wall repairable range

20-1: Unrepairable range of the furnace wall 30-1 to 10 Load drop trajectory by charging notch

40-1: Internal blast furnace loads 40-2: Internal blast furnace charges

40-3: Center blast furnace load 40-4: Small sintered ore charged in the blast furnace

50: no.PLC 50-1: charging amount control means for each notch

50-2: charging amount setting means for each notch

50-3: Charge hopper lead / raw material import signal generating means

60: raw material PLC 60-1: coke emission signal generating means

60-2: means for generating sintered discharge signal 60-3: means for generating sintered discharge signal

60-4: Trace signal generating means 60-5: Reset signal

70: electrical signal communication controller 80: basis weight value setting process computer

90: charging function selection means 90-1: small sintered light basis weight control means

In order to achieve the above object of the present invention, the present invention is a method for controlling the charging of the raw material / raw material based on the temperature from the temperature sensor installed in the furnace at regular intervals for each height, after the charging is started, the furnace temperature Detecting and comparing the detected furnace body temperature with a reference temperature; A second step of performing a normal charging according to a normal charging order and charging amount previously set for the lead / raw material including coke and the opposing sintered ore when the furnace temperature is lower than the reference temperature in the first step; In the first step, when the furnace temperature is higher than the reference temperature, the furnace temperature management mode is entered, and the basis weight of the lead / raw material is changed according to the charging order and the loading amount previously set for the lead / raw material including coke, allele sintered or small sintered ore. Performing a third step of transferring the basis weight of the fuel / raw material to the top hopper; When the basis weight of the small sintered ore reaches the predetermined target charge amount in the third step, the basis weight and the transfer process of the third step are repeatedly performed, and the basis weight value of the lead / raw material reaches the preset target charge amount. There is a fourth step to proceed to the next step; A fifth step of performing charging for each notch according to a charging order and charging amount previously set for the lead / raw material stored in the open hopper; After the charging of the first patch in the fifth step, the charging step for controlling the furnace temperature of the furnace characterized in that it comprises a sixth step to proceed to the first step.

Hereinafter, the configuration and operation of the charging system for the furnace temperature control of the blast furnace according to the present invention will be described in detail.

5 is a block diagram of a charging system for controlling a furnace temperature for carrying out the present invention. Referring to FIG. 5, a charging system for controlling a furnace temperature for carrying out the present invention is connected to a furnace PLC 50. (Iii) Through the internal notch charge amount control means 50-1 and the notch charge amount setting means 50-1, the connection is configured to set the angle so as to fall to the correct position for improving the peripheral flow formed in the furnace wall portion; In order to maximize the effect of the small sintered ore, the sintered ore with a particle size range of 5 to 10 mm can be selected and the ratio of the small sintered ore used according to the total amount of ore set by the manufacturer in the process computer 80 is set. When inputted, the amount of usage is automatically calculated, and the amount of small sintered ore selected by the small sized sintered ore particle size sorter is started based on the set basis weight value. It is configured to be equal to.

In addition, when charging of the charging hopper is completed through the charging control station PLC (50), when the lead / raw material import signal generation means 50-3 of the charging hopper generates a raw / raw material import signal it is in the raw material PLC (60) It is configured to discharge the small sintered ore stored in the small ore weighing hopper 4 through the lower gate (not shown), and to be loaded on the ongoing charging belt conveyor (5) and transported to the top, In order to adjust the charging mode (MODE) to control the amount of fuel input / raw material at the time of charging in the blast furnace, the notch charging amount setting means (50) is connected to the notch PLC (50) according to the number of revolutions of the small sintered ore charge amount. -2) and the notch charging amount control means 50-1 can be automatically adjusted.

In addition, a coke discharge signal generating means 60-1, an allied sintered discharge signal generating means 60-2, and a small sintered discharge signal generating means 60-3, which generate a corresponding discharge signal, each of which is a discharge signal. Is supplied to the raw material PLC 60 and the processor computer 80. In addition, the belt conveyor trace trace generating means 60-4 for providing a signal corresponding to the transfer state to the processor computer 80, and the belt conveyor trace trace generating means 60-4 are belt conveyors. At the start, a reset signal 60-5 is provided to the raw material PLC 60.

By the configuration of such a system, when charging the inside of the blast furnace is sprayed on the furnace wall to make a small ore layer to control the surrounding flow, the charging control according to the present invention by changing the normal charging order when the furnace temperature rises coke → alternatively sintered ore → small sintered ore.

6 is a flowchart illustrating a charging procedure for controlling the furnace temperature according to the present invention, and FIG. 9 is an exemplary view showing the charging amount for each notch of the charge when controlling the furnace temperature according to the present invention, and FIG. 10 is a furnace temperature according to the present invention. The blast furnace radial load distribution and gas flow distribution graph during control. 11 is a graph showing the present invention and the conventional furnace body temperature change trend.

Operation of the preferred embodiment of the present invention configured as described above will be described in detail below based on the accompanying drawings.

The present invention is a method for controlling the charging of the fuel / raw material based on the temperature from the temperature sensor installed at a predetermined interval for each height in the furnace body, which will be described in detail with reference to FIG.

First, in the first step S61, the processor computer 80 detects the furnace body temperature through the sensors S1-S9 shown in FIG. 7 after the charging is started, and then detects the detected furnace body temperature and the preset reference temperature. In detail, the furnace temperature is a temperature sensor below a preset height among a plurality of furnace temperature sensors, that is, the furnace temperature is divided into shafts 1 to 9 from the lower part to the upper part of the furnace body. When the sensor is installed for each shaft stage, the sensor may be at a temperature detected by a temperature sensor of four shafts or less among the plurality of furnace body temperature sensors.

7 is a blast furnace furnace temperature sensor installation state diagram, referring to Figure 7, the temperature sensor (S1-S9) according to the present invention is installed for a predetermined time from the lower end of the blast furnace furnace wall portion.

Next, in the second step S62, when the furnace temperature is lower than the reference temperature in the first step, the normal charging is performed according to the normal charging order and the loading amount previously set for the lead / raw material including the coke and the opposing sintered ore. Since this normal charging process corresponds to the same process as the conventional one, a detailed description thereof will be omitted. Here, the lead / raw material normal charging order is set in order of coke and an opposing sintered ore.

In more detail, the charging method in the normal operation of coke → coal sintered (17-20mm) in the order of the blast furnace when charged in the top, the coke and ore is mixed to maintain the porosity of the ore layer, the gas from the bottom rises A gas flow path is formed to maintain a balanced distribution in the circumferential direction, where the ratio of the ore's radial distribution for the central flow operation is about 20%, middle: 70%, and center: 10%.

Next, in the third step S63, when the furnace temperature is higher than the reference temperature in the first step, the furnace computer enters the furnace temperature management mode, and the processor computer 80 includes lead, coke, allied sintered ore and sintered ore. The loading order for the raw material and the loading order for the raw material including the coke, the allied sintered or small sintered ore and the basis weight control means 90-1 according to the control of the processor computer 80 Perform basis weight of lead / raw material according to the amount of charge. In this process, each of the coke discharge signal generating means 60-1, the sintered discharge signal generating means 60-2 and the small sintered discharge signal generating means 60-3 shown in FIG. Provided to the PLC 60 and the processor computer 80.

The weighted lead / raw material is transferred to the hopper, and this process is performed by the belt signal generating means 60-4 on the belt conveyor shown in FIG. 7 to provide the signal corresponding to the transfer state to the processor computer 80. The order of the lead / raw material charging in the furnace temperature management mode of the third step is set in the order of coke, opposing sintered ore, and small sintered ore.

If the furnace temperature cannot be controlled by the normal operation method in four shafts or less due to the wear of the refractory in the furnace due to the increase in the number of operating years of the furnace, that is, the temperature in the four shafts or less of the furnace shaft is within the control range (S1: 100 ± 20). ℃, S2 stage: 80 ± 30 ℃, S3 stage: 80 ± 30 ℃, S4 stage: 100 ± 20 ℃) If excessive ambient flow is formed, this is to be controlled. That is, when the temperature below the four stages of the furnace shaft rises above the management range, an alarm is given to the operator so that the operator can easily know, and in order to control the furnace body temperature, the coke → alternative sintered ore → When the charging method is changed in the charging function selecting means 90 to change the charging method (Fig. 9) in the order of small sintered ore (5 to 10 mm), the furnace body temperature management mode corresponding to the changed charging method is applied.

In the above process, in the process computer 80 of the present invention, the operator sets the basis weight value and the number of revolutions by determining the amount of use of the small ore by the ratio per charge in consideration of the operation characteristics of the blast furnace. In addition, the process computer 80 controls the charging in connection with the top PLC 50 and the raw material PLC 60 through the electrical signal communication controller 70.

The basis weight control means 90-1 inputs a small particle sintered ore ratio according to the amount of sintered ore of the current charge, and automatically calculates the amount of the small particle sintered ore selected by the small sintered ore particle size separator according to the set basis value. Is started and weighed in the small particle weighing hopper 4.

That is, in order to improve the effect of the small sintered ore as much as possible, it is possible to screen the sintered ore in the particle size range of 5 to 10mm and use the small sintered ore according to the total amount of ore set from the operator in the process computer 80 When the ratio is input, the amount of usage is automatically calculated to start the basis weight according to the set basis weight value of the small particle sintered ore selected by the small particle size sintered ore particle size separator and the basis weight in the small sized hopping hopper (4).

When charging of the charging hopper is completed through the charging control route PLC 50, when the lead / raw material import signal is generated from the lead / raw material import signal generating means 50-3 of the charging hopper, the raw material PLC 60 recognizes it. Thus, the small sintered ore stored in the small ore weighing hopper 4 is discharged through a lower gate (not shown), and loaded and transported in the ongoing charging belt conveyor 5.

Next, in the fourth step S64, before the basis weight value of the small sintered ore reaches the predetermined target charge amount in the third step, the basis weight and the transfer process of the third step are repeated, and the basis weight value of the lead / raw material When the target charge amount set in advance is reached, the process proceeds to the next step.

Next, in the fifth step (S65), the charging for each notch is performed according to the charging order and the loading amount previously set for the lead / raw material stored in the notch hopper, and the fifth step is to insert the small sintered ore into the notch near the furnace wall. The charging amount may be charged at a preset charge amount. Preferably, the small sintered ore may be charged at a preset charge amount at 1 to 3 notches near the furnace wall.

Through the notch charging amount control means 50-1 and the notch charging amount setting means 50-1 connected to the notch PLC 50, the angle may be dropped to the correct position for improving the peripheral flow formed in the furnace wall part. It is possible to set, and to adjust the charging mode by the charge amount / raw material discharge of the charges by the charging amount setting means 50-2 for each furnace internal notch.

And, in the third step of adjusting the charging mode (MODE) to control the charge / raw material emissions during charging in the blast furnace, the notch charging amount setting means connected to the notch PLC 50 by the number of revolutions per notch according to the small amount of sintered ore charge 5-2 and the notch charging amount control means 50-1, the values indicated in the table of FIG. 5 are set. Here, the blast furnace charge drop trajectory is as shown in FIG.

Through the above process, it is sprayed on the furnace wall during charging so that small sintered ore does not flow into the center of the furnace, and alleles and small sintered ore make a mixed layer to reduce the porosity of the charged material to control the surrounding flow. Perform temperature control.

In addition, the charging sequence is also changed, and referring to FIG. 10, the portion where the small grain sintered ore is charged is a portion (0 to 1 m from the furnace wall portion) in which peripheral flow flows to the furnace wall portion. It also prevents excessive flow of gas to the furnace wall by mixing with the air gap, thus protecting the vulnerable parts of thermal shock by furnace duct and abrasion. The same can be prevented in advance, thereby controlling the gas flow in the blast furnace.

Finally, in the sixth step S66, after the charging for the first patch is completed in the fifth step, the process proceeds to the first step and the charging for the next patch is repeatedly performed.

Referring to FIG. 11, in the graph showing the present invention and the conventional furnace temperature change trend, the graph on the left is the graph before the present invention, that is, the graph on the right, and the graph on the right is the graph of the present invention. As shown here, although the conventional furnace body temperature change was shown largely at the "4" point of the vertical axis | shaft, it turns out that there is no big change in this invention.

According to the present invention as described above, during operation of the blast furnace high draw ratio, by setting the charging mixture, the charging order and the charging amount of the lead / raw material to be charged according to the furnace wall temperature while detecting the temperature of the furnace wall portion, the furnace wall temperature rises By controlling the granular sintered ore to be charged in the furnace wall part, the temperature of the lower end of the furnace wall part of the furnace body can be managed in an appropriate range to prevent an increase in the furnace heat load, thereby improving the gas flow and breathability inside the blast furnace. Therefore, the situation in the furnace can be maintained stably, and there is an effect of increasing the production amount and protecting the blast furnace wall part.

That is, the effect of the present invention configured as described above is, first, when coarse → opposing sintered ore → small particle sintered ore temporarily when the furnace heat load point cannot be resolved due to operation action such as furnace wall repair and wall O / C increase. Secondly, it is possible to control the furnace temperature by charging the furnace, and secondly, it is possible to quickly and easily switch between the charging method for the furnace temperature management and the normal charging method, which can maximize the gas flow control with small particle sintered ore. The present invention plays an important role as a means for controlling the furnace body temperature as the number of operating years of the Gwangyang blast furnace increases in the future, thereby promoting practical operation of the outgoing costs and contributing to economic operation.

The above description is only a description of specific embodiments of the present invention, and the present invention is not limited to these specific embodiments, and various changes and modifications of the configuration are possible from the above-described specific embodiments of the present invention. It will be apparent to those skilled in the art to which the present invention pertains.

Claims (6)

In the method of controlling the charging of the lead / raw material based on the temperature from the temperature sensor installed in the furnace at regular intervals for each height, A first step (S61) of detecting the furnace temperature and comparing the detected furnace temperature with a reference temperature after charging is started; A second step (S62) of performing a normal charging according to a normal charging order and a charging amount previously set for the lead / raw material including coke and allied sintered ore when the furnace temperature is lower than the reference temperature in the first step; In the first step, when the furnace temperature is higher than the reference temperature, the furnace temperature management mode is entered, and the basis weight of the lead / raw material is changed according to the charging order and the loading amount previously set for the lead / raw material including coke, allele sintered or small sintered ore. While performing, the third step (S63) for transferring the basis weight of the fuel / raw material to the top hopper; When the basis weight of the small sintered ore reaches the predetermined target charge amount in the third step, the basis weight and the transfer process of the third step are repeatedly performed, and the basis weight value of the lead / raw material reaches the preset target charge amount. In the fourth step (S64) to proceed to the next step; A fifth step (S65) of performing charging for each notch according to a charging order and a charging amount set in advance for the lead / raw material stored in the open hopper; The charging method for the furnace temperature control of the blast furnace, characterized in that it comprises a sixth step (S66) to proceed to the first step after the charging of the first patch in the fifth step. The furnace body temperature of claim 1, wherein A charging method for controlling furnace temperature in a blast furnace, characterized in that the temperature detected by a temperature sensor below a predetermined height among the plurality of furnace temperature sensors. The furnace body temperature of claim 1, wherein When the furnace temperature sensor is installed at each shaft stage by dividing the shaft from the lower stage to the upper stage of the shaft from the first stage to the nineth stage, the temperature is detected by the temperature sensor of the shaft lower than four stages among the plurality of furnace temperature sensors. Charging method for furnace temperature control of blast furnace. The process according to claim 2, wherein the lead / raw material charging sequence of the second step is Coke, set in opposition sintered ore, The lead / raw material charging procedure in the furnace temperature management mode of the third step Charging method for controlling the furnace temperature of the blast furnace, characterized in that set in the order of coke, sintered ore, small sintered ore. The method of claim 4, wherein the fifth step A charging method for controlling furnace temperature in a blast furnace characterized by charging a small sintered ore into a notch near a furnace wall at a preset charging amount. The method of claim 4, wherein the fifth step A charging method for controlling the furnace temperature of a blast furnace, characterized in that the small sintered ore is charged at a predetermined charging amount into the 1 to 3 notches near the furnace wall.