JPH04198411A - Method for controlling molten iron tapping hole in blast furnace - Google Patents

Abstract

PURPOSE:To restrain molten iron tapping mixing gas, to extend molten iron tapping interval and to reduce the number of the molten iron tapping times, etc., by boring neiborhood of inner part of a molten iron tapping hole and mud material part in a furnace developing crack, etc., with the deterioration in the blast furnace larger than the ordinary method and pouring the mud material into the obtd. space part. CONSTITUTION:In inner part of molten iron tapping opening 2 arranged at side wall in the blast furnace body 1, the molten iron tapping hole 3 shown with the dotted line is arranged, and the mud material 5 is packed into the inner part of molten iron tapping hole 3 and to position from neighborhood of tip part to the furnace bottom 6. This mud material 5 part is opened in about 80-300mm diameter by using oxygen, etc., to the neighbor position at the very limit where the molten iron is not spouted out to dig the space part 7, and the mud material is buried into the space part 7 with a mud gun, etc. By this method, the part, where ordinarily the mud material is deteriorated and crack is developed and the gas is spouted, is sealed with the mud material 5 and the spout of gas is prevented.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a method for managing a blast furnace taphole, and more specifically, it involves making a large hole inside a deteriorated taphole and filling this hole with mud material. , a blast furnace tap hole that prevents cracks and suppresses gas-containing tapping (flying out), extends the tapping time, reduces the number of taps, reduces the tap slag work, and reduces the cost of mud material. Concerning management methods.

Conventional technology A normal large blast furnace has three to four tap holes, two of which are used for tapping alternately, and the remaining tap holes are used for tap runner repair and backup. These are usually used cyclically. The period of use of one taphole is about 20 days.For example, in a blast furnace with four tapholes, the explanatory diagram shown in Figure 3 showing an example of the usage pattern of the taphole and tapwater. There is a usage example like this.

This use case uses ITH for 20 days, then 4TH
During this period, ITH is used alternately with a repair period and a preliminary period.

Incidentally, mud materials, which are made by mixing fine coke, chamotte powder, clay powder, etc. with tar or petroleum binder, have traditionally been used to block the tapholes, and when opening the holes, this material is drilled and driven with a metal rod. I try to do it. That is, Fig. 4(a) shows the state of the tap hole blocked by mud material due to the tap stop, and Fig. 4(b) shows the state of the tap hole which is blocked by mud material due to the tap stop, and Fig. 4(b) shows the state of the tap hole which is approximately 3 hours after the start of tapping, almost at the end of the tapping period. Indicates the condition of the pighole.

By the way, the unused tap hole is in the state shown in Figure 4 (a), but the tap hole is in the state shown in Figure 4 (a) immediately before being transferred after the repair of the gutter is completed and it is kept as a reserve. It is thought that the situation is as shown in Figure (C). That is, the mud material inside the tap hole was worn out and cracked during about 20 days. For this reason, the tap hole immediately after the changeover involves tapping (rough soil) with gas blowing inside the furnace, so the tapping time may be shortened, so it is necessary to put enough mud material into such a tap hole. It takes about 2 to 3 days to stabilize the tapping, and an increase in the number of times of tapping during this period increases the burden of work in front of the furnace and increases the machine consumption rate. In addition, the rough soil tends to leave hot metal and slag in the furnace, which deteriorates the ventilation inside the furnace and causes poor furnace conditions.

In addition, Japanese Patent Application Laid-Open No. 58-58210 discloses that after opening the tap hole in 2 to 3 times during a wind break to the point where it does not penetrate into the furnace, filler with good fluidity and consisting of fine particles is used. There is a method for preventing blast furnace taphole gas leakage in which the enlarged part of the taphole brick joint and the cracked part of the discarded bottom layer in the furnace are closed by press-fitting.

In this method, the tap hole is opened in two or three times, and each time a filler with good fluidity and fine particles is injected under high pressure, filling the cracks in the tap hole. Although it has the advantage of being able to sufficiently press in the material, there are problems such as the work being complicated because the process of opening the tap hole and press-fitting the filler at high pressure is repeated at regular intervals.

Problems to be Solved by the Invention The present invention aims to solve the above-mentioned problems, and specifically, it provides a blast furnace tap iron in which the waste holes (cracks) inside the tap hole that have deteriorated immediately before transfer are plugged with mud material. The purpose is to propose oral management methods.

Means for Solving the Problems and Their Effects Namely, the present invention aims to repair the inside and surroundings of the blast furnace taphole where cracks have occurred in the mud material deteriorated by using oxygen, etc. and the mud material inside the furnace to the diameter of a normal taphole. The method is characterized by injecting ma-y-tooth material into the space obtained by excavating a larger area to prevent cracks in the area around the inside of the tap hole and the mud material in the furnace, and then tapping the hole through the hole.

Hereinafter, the structure and operation of the means of the present invention will be explained in detail with reference to the drawings.

In addition, FIG. 1 shows the inside of the blast furnace taphole in one embodiment of the method of the present invention. Fig. 2 shows the relationship between the number of tapping taps and the tapping time for each embodiment of the method of the present invention and a comparative example, and Fig. 3 shows the taphole, An explanatory diagram showing an example of an X-turn in the use of a tap hole is shown in Figure 4 (a
), (b) and (C) show the state of the taphole in the conventional example, where (a) is a longitudinal sectional view when it is closed, (one) is a longitudinal sectional view at the end of tapping, and (C) is a longitudinal sectional view when it is transferred.

Reference numeral 1 in FIG. 1 indicates a blast furnace main body, and a tap hole 2 is provided on the side wall of the blast furnace main body 1. Inside this tap hole 2, a tap hole 3, usually indicated by a dotted line, is provided. It consists of a mud material 5 filled inside the tap hole 3 and from near the tip of the inside tap hole 3 to the bottom of the furnace.

In the method of the present invention, a diameter of 80 to 300 holes is drilled between the inside of the tap hole 3 and the mud material part at the tip of the inside tap hole 3 to a position close to the point where hot metal does not spout out.
A space 7 is excavated by opening a hole about mm in diameter, and mud material is filled into the excavated space 7 using a mud gun or the like. In this way, when the space 7 is excavated from the inside of the tap hole 3 to the mud material part in the furnace and the mud material 5 is buried, the mud material part deteriorates and cracks occur, causing gas to spout out. is sealed by the matte material 51, and the ejection of debris is prevented.

If this method is used immediately before transfer or if there is a lot of rough soil 1
By implementing this method, it is possible to suppress the amount of rough soil compared to the conventional method where nothing is done at the time of transfer, and the tapping time is extended, the number of times of tapping is reduced, the load on tapping slag work is reduced, and the cost of mud material is reduced. It becomes possible.

The present invention will be further explained below with reference to Examples.

Embodiment 1 Immediately before changing the tap hole 2 of the blast furnace body 1, the normal tap hole 3 is changed to the limit where the internal tap hole 3 of the tap hole 2 and the hot metal in the furnace mud material 5 are not tapped. 80-30 which is larger than the diameter
A hole having a size of 0 mm was opened, and a commonly used mud material 5 was embedded in the resulting space.

Tapping was performed by transferring to this taphole 2, and the relationship between the number of tapping taps and the tapping time is shown in FIG. 2.

For comparison, FIG. 2 also shows the results of drilling a new hole as in Example 1 at the time of transferring the conventional example and performing tapping without filling the mud material.

As in the conventional example shown in Figure 2, it took three days (approximately 12 taps) to stabilize the tapping after transfer, but the second
In the case of Example 1 shown in the figure, the level reached the normal level after 5 to 6 taps.

In addition, there is no rough soil immediately after transfer, which normally occurs in conventional cases.
It was possible to perform stable tapping from the beginning, and the number of read pig iron tappings was significantly reduced.

In addition, in Example 1, data at the time of transfer was explained, but only at the time of transfer (limited, gas blowing from the tap hole)
I have found that this method is effective whenever the soil is severely damaged.

Example 2, The commonly used embedded mud materials are Si and N.

The same procedure as in Example 1 was conducted except that the material had a high content of silicon nitride (silicon nitride) and was hard and corrosion resistant. The results are also shown in FIG.

The results of Example B revealed that the method was much less effective than that of Example 1.

<Effects of the Invention> As explained in detail above, the method of the present invention replaces the area around the inside of the blast furnace taphole where cracks have occurred in the mud material deteriorated by using oxygen, etc., and the mud material inside the furnace, by reversing the diameter of the normal taphole. Inject mud material into the space obtained by excavating a larger area to prevent cracks around the inside of the tap hole and the mud material inside the furnace,
It is characterized by open hole tapping.

According to the method of the present invention, the inside of the tap hole is excavated with oxygen, etc. to a diameter larger than that of a normal tap hole, and the inside of the mud material inside the furnace is also wide. Since the cracks inside the tap hole are reliably sealed, it is possible to suppress the tapping of slag (rough soil), which extends the tapping time, reduces the number of times of tapping, and reduces the burden of tapping slag work. It has become possible to reduce the amount of waste and reduce the cost of mud materials.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view showing the repaired part inside the blast furnace taphole in one embodiment of the method of the present invention, and Figure 2 is the number of tapping taps and tapping time of each embodiment of the method of the present invention and a comparative example. Fig. 3 is an explanatory diagram showing an example of the usage pattern of the taphole and tap sluice, and Fig. 4 (a), (b) and (C) are graphs showing the relationship between the The state is shown, (a) is a longitudinal sectional view at the time of blockage, (1) is at the final stage of tapping, and (c) is a longitudinal cross-sectional view at the time of transfer. Code 1 - Blast furnace body 2 Tap hole 3 Tap hole 4 - Rein force 5 Mud material 6 Hearth bottom 7 - Space 8 Crack

Claims (1)

[Claims] 1) Add mud material to the space created by excavating the area around the inside of the blast furnace taphole where cracks have appeared in the mud material deteriorated by using oxygen, etc., and the mud material inside the furnace to a diameter larger than that of a normal tap hole. A method for managing a blast furnace tap hole, which comprises: pouring the iron into the hole, preventing cracks around the inside of the tap hole and the mud material inside the furnace, and then tapping the hole with the hole open.