KR20050012907A - A method for ensuring tapping depth in tap hole of blast furnace - Google Patents

Abstract

PURPOSE: To provide a method for protecting surrounding facilities, improving safety of workers and realizing stability of blast furnace operation through stabilization of tapping operation by securing tapping depth of tap hole during initial tapping operation after stoppage of tap hole, thereby normally discharging hot metal into runner. CONSTITUTION: The method for securing tapping depth of blast furnace tap hole comprises a tap hole(40) stoppage step closing the blast furnace tap hole with mud after tapping operation; and a tap hole depth securing step of securing tap hole depth by filling and pressing the mud into the tap hole right after performing an initial tapping operation through opening of the tap hole after stoppage of the tap hole, thereby reinforcing a mud portion of the inner wall side of the blast furnace that is worn out during stoppage of the tap hole so that hot metal is discharged into a runner during re-tapping through a tap hole of which tapping depth is secured by recharging of the mud, wherein temperature of the mud recharged in the tap hole depth securing step is 80 to 100 deg.C, and a charging amount of the mud is 300 to 500 mm.

Description

How to secure the depth of departure at the blast furnace exit {A METHOD FOR ENSURING TAPPING DEPTH IN TAP HOLE OF BLAST FURNACE}

The present invention relates to a method for securing the depth of departure of the blast furnace exit port to ensure the depth of the exit port in which the molten iron can be discharged to the waterway during the opening of the exit port in order to discharge the melt in the blast furnace, It is possible to stably manage the blast furnace exit, and by refilling the mud materials after the first departure through the opening of the exit after the blast furnace is stopped, the molten iron is discharged to the water supply while securing the depth of the exit at the next departure. The present invention relates to a method for securing the depth of departure at the blast furnace exit to maintain the stable operation of the ship and to prevent various equipment and operation troubles by preventing the slag discharge due to the depth failure of the exit.

As shown in Figure 1 and 2, the blast furnace operation is to charge the hot air through the tuyeres 20 by charging the ore as a raw material and the coke as a heat source in the blast furnace 10, through this process, through the process For example, the molten iron 30 generated from the molten iron 30a and the slag 30b are collected in the lower part of the blast furnace, and the molten melt 30 is discharged through the outlet 40 provided in the lower part of the blast furnace.

However, the inside of the outlet 40 is filled with a mud material (MUD) 72, which is an indefinite refractory material, and in order to discharge the internal melt 30 to the external water supply 50, the outlet ( 40) is opened by the opening device 60 as shown in FIG.

At this time, the outlet 40 is coupled with the set edge 12 of the blast furnace 10 is not indicated by a separate reference in the drawing in the state penetrated into the protective wall to the outside in the state and the inside of the protective wall about 700mm again The inflow material CR-S10 is constructed to a depth and the stamp material is installed in the inflow material, and the mud material 72 is closed when the exit opening 40 opened by an excavation work as the opening device 60. ) Is filled with the mud gun 70.

That is, the opening 40 is excavated using the opening device 60 as shown in FIG. 1 to open the outlet 40 to form a flow path so that the melt 30 can be drawn out.

After discharging the melt 30 of the blast furnace 10 for a predetermined time after the opening work is completed, at the time when the discharge of the melt 30 in the blast furnace is almost discharged, a tap opening (using the mud gun 70) is used. 40) filling the mud material 72 to perform the closing operation of the exit opening 40, and when the blast furnace operation, such opening and closing operation of the exit opening 40 is made continuously, such melt discharged The opening of the exit gate and the closing of the exit port, if necessary, are called the start operation.

On the other hand, although shown schematically in the drawing, the blast furnace outlet 40 is different depending on the blast furnace 10. A total of four outlets 40 are formed in the large blast furnace 10, of which three outlets 40 alternately perform turns in turn, and the other one outlet 40 is 50 is to be stopped for the repair of the runner connected thereto.

Next, when the blast furnace is repaired and the drawing work is proceeded with the normal melt through the initial drawing work, the other tap is stopped again.

By the way, the outlet 40, which is the target of the repair work, is divided into major repairs and minor repairs, and rests for about 12 to 15 days and repairs the runway 50 and each runner raceway. In this case, since the tap opening 40 is not opened and the mud material 72 is not filled, in such a case, the tap opening 40 is connected to the tap opening 40 through the mud gun 70 before the tap opening 40 is stopped. The mud material 72 is filled in the tap opening 40 to secure the depth of the tap opening 40.

At this time, in securing the depth of the exit opening 40, the mud material 72 is usually managed to be about 3000 to 3500 mm, which is to improve its porosity in the subsequent opening through the opening device 60. At the same time, it is for the reduction of the mud material 72 is filled in the outlet 40.

However, as shown in FIG. 3, when the blast furnace 10 is operated but the selected outlet 40 is idle for a long time, the melt 30 in the blast furnace 10, that is, the molten iron 30a and the slag ( The depth of the tap hole 40 gradually decreases as a part of the mud material 72 which is filled by the vortex phenomenon of 30b), blocks the tap hole 40, and forms a protective wall, and then forms a molten iron ('A' in FIG. 3). Problem occurs.

Therefore, as shown in FIG. 4, when the depth of the shortened portion is shortened due to the damage of the inner filling mud material portion of the exit tap 40 thus rested, the melt 30 in the blast furnace 10 is discharged at the low level. Since the height of the precursor 40 is formed high, in this case, the molten iron 30a of the melt 30 sinks to the lower part because of its high specific gravity, and the slag 30b floats upward because of its low specific gravity, so that the discharge port 40 is discharged. When the height is high, the slag (30b) is discharged first to the waterway (50) side during the initial ship operation.

As a result, when the slag 30b is discharged first, when the slag 30b is discharged first from the tap opening 40 in the cooled state without the latent heat, although the drying of the runway 50 and the runner is completed, The slag 30b in contact with the runner 50 is rapidly cooled and hardened to block flow paths such as a skimmer, a discharger, and a second block, which are the separation device of the molten iron 30a and the slag 30b. As a result, serious equipment accidents have often occurred that the melt overflows in the runway 50 and the runner.

Meanwhile, in order to prevent such a problem, the method of delaying the departure time until now is mainly used, but even when delaying the departure time, the rise of the low level due to the poor discharge of the melt 30 and the wind pressure inside the blast furnace increase accordingly. In order to cause the cause, there is a problem of operating instability of the blast furnace 10 itself.

The present invention has been made in order to solve the conventional problems as described above, by securing the depth of the exit port in advance during the start-out operation after the exit port to protect the peripheral equipment through the stable discharge operation by the normal discharge of melt In order to improve worker safety and stabilize the blast furnace operation, if the depth of the exit drop during the blast furnace operation, the refilling work is performed in parallel to secure the depth of the exit of the blast furnace. To provide.

1 is a structural diagram showing the opening work to open the blast furnace opening through the opening machine

2 is a structural diagram showing a mud operation for closing the open blast furnace exit using a mud gun

Figure 3 is a structural diagram showing the depth of the exit for the exit at the blast furnace exit for a long time

Figure 4 is a state diagram showing the slag discharged state at the time of initial departure in the depth of the conventional exit port molten state

Figure 5 is a relative view showing the exit closure and depth secured immediately after the first departure through the blast furnace exit depth securing method of the present invention

Figure 6 is a state diagram showing the molten iron discharge state at the time of re-exiting the stop of the blast furnace according to the invention after a long pause.

Explanation of symbols on the main parts of the drawings

10 .... blast furnace 20 ....

30 .... melt 40 .... exit

50 .... Tangdo 60 .... Opening Equipment

70 ... Mudgun 72 ... Mud Ash

The present invention as a technical configuration for achieving the above object, in the method for securing the departure depth of the blast furnace outlet, the outlet stop step of closing the blast furnace outlet as a mud material after the starting operation; And

Outlet depth securing step of securing the depth of the outlet by reinforcing the mud material on the inner wall of the blast furnace during the stop of the outlet by press-filling and filling the mud material into the outlet immediately after opening the outlet through the opening of the outlet. Done by

It is characterized by the fact that the chartered ship is discharged to the waterway when re-electing through the exit port, which has the depth of departure secured by refilling the mud material.

Hereinafter, the present invention will be described in detail.

Figure 5 is a relative diagram showing the exit closure immediately after the first departure through the blast furnace exit depth securing method of the present invention and the depth secured state, Figure 6 is a re-starting time according to the invention after the blast furnace exit for a long time stop It is a state figure which shows the molten iron discharge | release state, and the same structure as the conventional structure is shown with the same code | symbol.

First, as shown in FIG. 5 and FIG. 6, the stop of the exit 40 is made. At this point, when the exit of the exit 40 which requires maintenance for a long time as in the prior art ends, mud To fill the ash (72) to the maximum to block the discharge of the melt (30),

At this time, the mud gun 72 is put into the fuselage of the mud gun 70 as much as possible, and the mud gun as soon as the starting point is closed in a state in which the mud material 72 is preheated to a suitable temperature, for example, between 60 and 70 ° C. Through the 70, the mud material 72 is tightly filled in the entire exit port 40 to secure an initial depth. The initial depth of the exit port is increased by increasing the amount of the mud material 72 more than before. It is important to ensure that

Next, when the outlet 40 is at rest, the repair operation of the runner 50 and the runner corresponding thereto is performed, and the outlet 40, the runner 50, and the runner which are at rest in the same state as the outlet. To repair the back.

At this time, the normal operation process for repair of the runway 50 and the runner is made in the order of cooling-> excavation (crushing)-> construction-> drying, when all such repair work is completed, other The preparation of the starting line with the preparation of the stop 40, the normal maintenance period is 12 to 15 days, such as the rest period.

On the other hand, in the present invention in the depth securement step of the exit opening through filling the sufficient exit opening 40 of the mud material 72 is characterized in that the operation to close immediately after opening the exit opening 40.

That is, when discharging the melt through the tap opening 40, the blow bar of the tap opening opening device 1 generally uses a bit diameter of 56 to 60 mm, but is practically used during the tapping work according to the present invention. Open the hole using 60mm, the largest of the diameters of the strokes.

Next, when the opening is completed and the retreat of the opening device 60 is confirmed, the mud gun 70 is turned to immediately close and the mud material 72 is filled as much as possible to cope with the melting loss by the melt in the blast furnace. Enough depth of pioneer.

In addition, the work method is changed according to the present invention even in the step of re-drawing, the opening time is different depending on the condition of the exit port and the aging, but the tapping is about 2 taps in consideration of the firing time of the mud material (72). If the starting gate is stable by performing normal starting work, proceed to the next stop work.

In case of abnormal opening of openings or equipment troubles, emergency closing of the openings and preparation for re-employment are performed.

And, the depth of the tap opening 40 should be more than 3000mm, preferably the appropriate depth of the tap opening 40 is between 3000mm to 3500mm, which is managed when the depth of the melt 40 as described above That is, it is because discharge | ejection and drawing time of molten iron | metal 30a and slag 30b are suitable.

However, since the mud material 72 cannot be filled when the outlet is at rest, when the stop of the outlet 40 is planned, the filling amount is gradually increased and the mud material 72 is press-fitted as much as possible during the last closing operation. In the blast furnace, a sufficient protective wall should be formed. As shown in FIG. 3, the inner protective wall of the mud material 72 filled with the melt 30 vortexed in the blast furnace 10 in operation when the exit port 40 is idle. This gradually melts (A), so as to solve the problem of shortening the depth of the first ship work to be forced to press the amount of mud material 72 as much as possible.

At this time, as described above, the starting depth of the tap opening 40 through the preferred mud material filling is preferably 3000mm or more.

Next, when the stop of the tapping opening 40 is completed, refractory repairs such as molten and oxidized taping due to high heat melt during blast furnace operation are performed, for example, remaining in the taping opening-side tapping 50 closed. One molten material 30 is completely removed by using the remnant exhaust hole, and the runner 50 and the runner connected thereto are operated in the order of cooling-> excavation-> construction-> drying as described above. Do the following.

Then, when all the maintenance work is completed, the preparatory work for stopping the other tapping opening 40 is performed, and the preparatory work for the initial drawing work is performed.

At this time, when 12 to 15 days, which is the rest period of the exit opening 40, has passed, the fired mud material 72 forming a protective wall on the inner wall of the blast furnace is gradually melted as shown in FIG. The depth of the exit port is gradually shortened by digging into the exit port 40 to the outside of the blast furnace 10.

Therefore, the starting depth of the exit at the time point of repair of the runway and the runner is completed. According to the result of the initial drawing operation according to the conventional working method, the depth of initial departure according to the protection wall melting loss A in the furnace as shown in FIG. It will be between 1800mm and 2200mm.

However, as described above, when the depth of the exit port is shortened as described above, various problems occur, so that the initial drawing work at the conventional exit port in order to allow the molten iron to be discharged first in the melt in the furnace requires a departure time of 1 hour. Will be delayed by 20 minutes.

However, in this case, the low ship level rises with the increase of the furnace contents 30, and thus the wind pressure rises, which causes a big problem in the blast furnace operation. Therefore, there is a limit in sufficiently delaying the departure time. Increasing wind pressure can lead to other problems, such as air blasting or opening the exit early.

By the way, in the case of using the method for securing the departure depth of the blast furnace exit according to the present invention, when the repair of the runway 50 and various runners is completed, the preparation work for the first departure is performed first as before.

That is, the mud gun (70) preheating work and the operation of blocking the outlet and the second block of the water supply (50), easy closing operation of the tap opening (40) through the mud gun 70 It is necessary to preheat the mud material 72 sufficiently to make it.

On the other hand, conventionally managed the preheating temperature of the mud material between 60 ℃ to 70 ℃ but since the re-closing is made in the shortest time after the departure, since the starting hole of the tap opening 40 through the opening device 60 is not expanded, the present invention In the case where the preheating temperature of the mud material 72 is managed between 80 ° C. and 100 ° C., which is higher than that of the related art, the filling amount of the mud material 72 increases and the depth of the mud material 72 increases.

In addition, when using the opening device 60 to open the exit 40 is repaired in the state that the other exit port 40 in use in accordance with the present invention, the molten material 30 is discharged in general, the exit port Depth of about 1800mm to 2200mm so that the exit port 40 is formed higher than the low line level of the melt 30 in the furnace, the light weight of the slag 30b is discharged first.

That is, in such a case, when the ship is out for a long time, a phenomenon in which the melt 30 overflows may be generated by blocking the flow path of the tap water 50, the runner, and the skimmer by the solidification of the slag 30b.

Therefore, in the present invention, in order to reinforce and secure the depth of drawing of the tapping opening 40 first, the tapping opening 40 which is first drawn out after a certain period of time is opened as the opening device 60 without opening the tapping work without opening work. When the 60 quickly retreats, the surface state of the tapping opening 40 is confirmed, and then the preheated mud material 72 is quickly forced and filled with a large amount of the preheating mud 72 to the tapping opening 40 with the mud material 72. Reclose).

As a result, as shown in Fig. 4, conventionally, the blast furnace inner wall-filled mud material 72 is melted for a long time, so that the depth of departure is not secured. Solving the problem that 30b) is out of the waterway (50) is to secure the depth of departure at the time of departure, the present invention is re-opening operation by reopening the exit opening 40 in a state of sufficient depth, At this time, only the molten iron (30a) is to be discharged through the blast furnace outlet first, in which case various problems due to the slag discharge is solved.

At this time, the reopening time of the tap opening 40 filled with the mud material 72 varies depending on the starting conditions or blast furnace aging, but considering the time for the mud material 72 to be stably fired in the furnace and the inner wall of the tap opening 5 After about an hour, the opening is performed again as the opening device 60 to perform the redrawing operation.

For example, the reinforcement depth of the exit port in this way is when the re-employment work is carried out depth of 2300mm to 2700mm, the depth of about 500mm to 900mm compared to the conventional work method is secured.

Next, Table 1 below shows the data related to the mud material for securing the depth of the exit at the blast furnace.

division Opening Bits Outlet Depth Mud Reheating Temperature Mud refill amount Oil pump pressure (kg / ㎠) Tilt amount Re-exit depth Remarks 1st (# 1 exit) 58 mm 1800mm 60 ℃ 200 mm 260-280 730 2100mm Bad 2nd (# 3 exit) 58 mm 1900 mm 70 ℃ 230 mm 250-280 725 2100mm Bad 3rd (# 2 exit) 60 mm 1800mm 70 ℃ 250 mm 240-280 720 2200 mm Bad 4th (# 4 exit) 60 mm 2000 mm 80 ℃ 300 mm 220-260 730 2300 mm Good 5th (# 1 exit) 60 mm 2000 mm 90 ℃ 400 mm 210-250 710 2500 mm Good 6th (# 3 exit) 60 mm 1900 mm 100 ℃ 500 mm 200-240 720 2700 mm Good 7th (# 2 exit) 60 mm 1900 mm 110 ℃ 600 mm 190-230 730 2100mm Bad 8th (# 4 exit) 60 mm 1800mm 120 ℃ 600 mm 180-220 725 2000 mm Bad

That is, as shown in Table 1, the filling pressure of the mud material 72 is different depending on the preheating state of the mud material 72 or the state of the opening port opening, but in the general drawing operation of the mud gun 70 The oil pump pressure is in the range of 180 kg / cm 2 to 220 kg / cm 2, which means that the mud material 72 has a low preheating temperature but is press-fitted in the mud material 72 because the tap opening is enlarged in the case of long time drawing operation. Because this is easy.

However, as shown in Table 1, even if the preheating temperature is formed high according to the present invention, it can be seen that in the state that the X-ray bulb 40 is not enlarged, various changes are made in the depth of the exit port according to the first bit diameter and the preheating temperature. have.

That is, in Table 1 and 1, the first and second bit diameters of the opening device 60 in the first and second, using a maximum 58mm, and the pre-heated mud material at about 60 ℃ ~ 70 ℃ as in the prior art, the mud gun 70 As the oil pressure of the machine increased rapidly, the filling amount was filled about 200 ~ 300mm, but the starting depth was about 2100mm, and in the third round, the single bit diameter was made as 60mm to close the mud material preheated to about 70 ℃. As a result, the pressure of the oil pump was slightly decreased, but it was found to be insufficient to secure the depth of the outlet.

On the other hand, in the fourth to sixth stages, the mud material with the bit diameter fixed at 60 mm and the preheating temperature preheated to 80 to 100 ° C. was filled in the tap opening 40, and the pressure of the oil pump was 260 kg / cm at 220 kg / cm 2. It can be seen that about 2 cm2 was maintained and the depth of departure of the first exit port was about 2300mm-2700mm.

Next, in the seventh and eighth stages, when the temperature of the mud material was preheated to 110 ° C or more, the closing pressure was kept low, and the filling amount of the mud material could be increased, but the mud material which was easily pushed into the furnace without being filled at the exit port was rapidly oxidized. In addition, it can be seen that it does not play a large role in forming the protective wall.

At this time, the pressure of the oil pump is usually made in the pressure range of 200BAR-260BAR and pressurized as much as possible to fill the blast furnace to form a protective wall and to secure the depth.

Therefore, as shown in Figures 5 and 6, in the method for securing the exit depth of the present invention, after the break for a long time, during the starting operation through the exit port, the first bit diameter of the opening device is about 60 mm immediately after opening the opening port. The mud material 72 preheated to 80 to 100 ° C. is forcedly press-filled in an amount of approximately 300-500 mm through the exit port 40 so that the depth of the exit port, that is, more than the slag 30b floating in the melt at the time of departure, is increased. The molten iron (30a) is to be taken out through the opening.

Next, when the starting port is stabilized by the above method and the normal starting work is performed by securing the depth, the stop working of the starting port, which is the next maintenance turn, is performed. If the opening of an abnormal exit or equipment trouble occurs, the exit should be closed again by emergency closing of the exit and preparation for re-employment.

Therefore, according to the method for securing the depth of departure of the blast furnace exit according to the present invention, it is possible to apply a sudden depth deterioration of the exit during the blast furnace operation, closes immediately after the departure of the corresponding exit and after a certain time has passed again The same process can be applied to performing line work.

And, as shown in FIG. 6, even when the mud material 72 is melted at the exit stop by the exit depth securing method of the present invention, the molten iron 30a in the melt 30 first starts the water supply 50. In order to eliminate the problems caused by the prior discharge of the slag 30b as in the prior art, it is possible to eliminate the problem.

As described above, according to the method for securing the departure depth of the blast furnace exit port according to the present invention, the slug is discharged first when the exit depth is shortened in the state where the exit depth is shortened. It provides the advantage of resolving the problems that caused the instability of old age.

In addition, the above working method has an effect of making it possible to utilize the refilling operation to secure the depth of the outlet when the depth of drop suddenly drops when the protective wall is dropped out of the furnace outlet during operation.

Therefore, by releasing the workload of the super-extracting work that remains the biggest difficulty in the blast furnace operation and securing the stability of the blast furnace operation to provide an excellent effect that can greatly contribute to the improvement of blast furnace productivity.

While the invention has been shown and described in connection with specific embodiments so far, it will be appreciated that the invention can be varied and modified without departing from the spirit or scope of the invention as set forth in the claims below. It will be appreciated that those skilled in the art can easily know.

Claims (2)

In the method of securing the depth of departure at the blast furnace, A tap stop phase of closing the blast furnace tap exit as a mud material after the tapping operation; And Outlet depth securing step of securing the depth of the outlet by reinforcing the mud material on the inner wall of the blast furnace during the stop of the outlet by press-filling and filling the mud material into the outlet immediately after opening the outlet through the opening of the outlet. Done by A method of securing the depth of departure of a blast furnace exit, characterized in that the charter is configured to be discharged to the waterway when re-emission through the exit has secured the depth of mud material. 2. The method of claim 1, wherein the temperature of the mud material refilled in the exit depth securing step is 80-100 ° C and the filling amount is 300-500 mm.