JPH1096005A - Method for disassembling furnace-bottom part in blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disassembling method for furnace-bottom part in a blast furnace, in which the working time is shorter than a conventional method, the cost is low and the working environment is good. SOLUTION: At the time of executing the blowing-down of the blast furnace and the carrying-out and removal of solidified material layer 2 and a furnace- bottom brick layer 1 remaining at the furnace-bottom part to the outside of the furnace, the furnace body of the blast furnace is horizontally cut off at the higher position than the solidified material layer 2. After hanging and fixing the upper furnace body from the cut-off position with supporting columns 4 as it is, the lower furnace body from the cut-off position is removed over the whole periphery of the furnace body to integrally pull out the solidified material layer 2 and the furnace-bottom brick.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dismantling a blast furnace, and more particularly, to a technique for dismantling and removing solidified material remaining on a furnace bottom after blowing off integrally with a furnace bottom brick.

[0002]

2. Description of the Related Art A conventional method of disassembling a furnace bottom when refurbishing a blast furnace or the like will be described. Destroy with heavy equipment and make holes to allow the heavy construction equipment to enter the furnace bottom. Then, the coke remaining in the furnace bottom is extruded out of the furnace by the heavy construction machine and removed. After that, an operator enters the furnace and uses a rock drill or blasting machine to mix approximately 300 to 500 tonnes of coagulated iron (slag or coke) remaining underneath (unified like a monolith). Crushed) and transported to the outside of the furnace, and further, the above construction heavy equipment destroys the bottom carbon brick and transports the brick to the outside of the furnace.

[0003] In the refurbishment work of the blast furnace, it is necessary to shorten the construction period as much as possible. Therefore, the dismantling work is started before the bricks in the furnace and the solidified material are completely cooled to room temperature. The work environment is a place where there is only the above-mentioned hole at the bottom of the furnace and a manhole at the top of the furnace, and a lot of dust is generated (a so-called 3K workplace). In addition, since the bricks on the furnace wall and the furnace bottom and the solidified material are hard and heavy, they need to be divided into small pieces in order to carry them out of the holes and manholes. Therefore, the time required for the conventional disassembly work is very long (long work and high cost work).

[0004] Therefore, for the purpose of reducing the work in such a bad environment as much as possible, for example, Japanese Patent Publication No. 45-19468.
Japanese Patent Application Laid-Open No. H10-216550 has developed a blast furnace lining brick crusher and has proposed the mechanization of work inside the furnace. However, even if this mechanization technology is adopted, since the machine is operated in a narrow place,
It is economically preferable to prepare and prepare specially-used expensive dismantling equipment for blast furnace renovation once every ten years or more, which requires skill in operation techniques and for one blast furnace. That was not the case.

[0005]

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a method for dismantling a blast furnace bottom having a shorter working time, a lower cost, and a better working environment.

[0006]

Means for Solving the Problems The inventor studied efficient dismantling to achieve the above object, and conceived of carrying out and removing the bottom solidified layer out of the furnace integrally with the bottom brick layer. did. Then, they worked diligently to realize the present invention and completed the present invention. That is, the present invention blows down the blast furnace and carries out the coagulated material layer and the bottom brick layer remaining at the bottom of the furnace to the outside of the furnace, and removes the furnace body of the blast furnace at a position higher than the solidified layer. After the furnace body above the cutting position is suspended and fixed by the blast furnace column as it is, the furnace shell below the cutting position is removed over the entire circumference of the furnace body, and the solidified material layer and the furnace bottom are removed. This is a method for dismantling the bottom of a blast furnace, wherein the bricks are integrally pulled out of the furnace.

The present invention is also characterized in that the furnace bottom brick layer is cut horizontally with a wire saw along the bottom thereof to separate it from the blast furnace foundation, and is drawn out of the furnace with the solidified layer placed thereon. Of the bottom of the blast furnace. Furthermore, the present invention is also a method for dismantling a blast furnace furnace bottom, wherein the furnace bottom brick layer is drawn out using a horizontal pulling means, a truck and a dolly mount.

In the present invention, since the bottom of the blast furnace is dismantled with the above-described structure, the working time is shorter, the cost is lower, and the working environment is improved in comparison with the related art. .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A method of dismantling a blast furnace bottom according to the present invention will be described below, following the procedure. After the final tapping of the blow-off operation, an opening is provided in the furnace bottom with a drill, and the hot metal and slag remaining in the hearth are discharged from this opening, and then water is injected from the upper part of the furnace body. After cooling the furnace residue and the furnace body, the dismantling method according to the present invention is performed.

First, as shown in FIG. 2, the furnace body is suspended from the tuyere level of the furnace body to the column 4 via the lift jack 5. This is for supporting the upper part of the furnace body when the furnace bottom is cut off thereafter. Next, the iron shell at the furnace bottom at a position 10 or less higher than the upper surface of the solidified material layer 2 remaining on the furnace bottom brick layer 1 is removed, and the lower part of the furnace body is opened. The method of removing the steel shell may be any method, but the steel shell 3 is cut horizontally about 1000 to 2000 mm above the bottom plate level, and the steel shell 3 is cut vertically from the position 10 to form a petal. A simple method is to cut the petal-shaped steel bar 3 horizontally at the position 10 and carry it out. The upper brick at the lower part of the opened furnace body is broken by the heavy construction machine 15, and the residue in the furnace that can be easily broken, such as a coke layer, is discharged out of the furnace by the heavy construction machine 15, and the furnace bottom is leveled. (Described later) so as not to come into contact with the remaining furnace shell above the position 10. The coagulated material layer 2 usually has a weight of 300 to 500 tons, a diameter substantially close to the hearth diameter, and a height of about 3.5 m.

Next, in the present invention, as shown in FIG. 1, the coagulated material layer 2 is integrated with the furnace bottom brick layer 1 and is taken out of the furnace so as to be taken out of the furnace. Layer 1 is cut horizontally and separated vertically. This cutting is performed in one or two stages of carbon brick at the bottom of the furnace. This means that hearth bricks of this level usually remain in good condition even during renovation,
This is because the cutting powder of the carbon brick has an effect of lowering the frictional resistance when the furnace bottom block is pulled out later. Here, an example in which this cutting is performed by the wire saw 7 is shown. Several holes are drilled in the steel shell by core boring above the level at which the hearth brick layer is cut up and down, and as shown in FIG. Join between. Thereafter, as shown in FIG. 3 (a), a horizontal and penetrating hole 8 for passing the wire saw 7 is formed in the hearth brick layer 1
And open using core boring. As shown in FIG.
By passing the wire saw 7 through the through hole 8 and operating the same, the furnace bottom brick layer 1 is cut. In the figure, the hatched portion indicates the cut surface by the wire saw. This cutting is, in principle, to cut the whole of the hearth brick layer 1 on a horizontal plane.
In this example, four wire saws 7 are used. However, in a blast furnace in which the distance between the columns 4 is narrow, the diameter of the bottom layer 1 is too large, and the space between the columns 4 is unloaded during the unloading.
May not be able to pass. In this case, in the present invention, the hearth brick layer 1 and the solidified material layer 2 thereon may be vertically cut and divided into several blocks.

As shown in FIG. 5, the hearth brick layer 1 and the solidified material layer 2 cut by the wire saw 7 and opened from the blast furnace foundation 6 are wrapped with a wire on the hardware 9, and are not shown. It is pulled by a holding means (for example, a win 4 or a jack), and is placed on a carriage 13 waiting on a work floor 12 beside the furnace body. Then, the truck 13 is moved, mounted on the dolly frame 14 in a standby state together with the truck 13, and is carried out from the vicinity of the blast furnace by a trailer (not shown) or the like.

The method of disassembling the blast furnace bottom according to the present invention was applied to refurbishment of a blast furnace having an inner volume of 2600 m ³ and a hearth diameter of 11.4 m. As a result, the work time from cutting of the iron shell 3 to completion of unloading of the furnace bottom brick layer 1 and the solidified material layer 2 was two days. Conventionally, the work corresponding to this was performed in 5 days, and it is considered that the present invention has greatly improved the efficiency of dismantling the furnace bottom. Also, the present invention
Since there is no need for special equipment or equipment, it can be implemented using existing ones, so equipment costs are low and man-hours can be reduced, so that dismantling work has been greatly reduced. Further, since the number of opportunities for workers to enter the furnace is reduced as compared with the conventional case, there is also an effect of reducing so-called 3K work.

[0014]

As described above, according to the present invention, the solidified material remaining at the bottom of the blast furnace after the blow-off can be carried out of the furnace and removed integrally with the bottom brick. As a result, the furnace bottom can be easily disassembled in a shorter time than before.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state in which a method of dismantling a blast furnace bottom according to the present invention is performed.

FIG. 2 is a view showing a situation in which the iron skin is opened in a petal shape before the disassembly method according to the present invention is performed.

3A and 3B are diagrams in which a through hole is opened in a furnace bottom brick layer and a supporting hardware is attached, (a) is a side view of a furnace bottom portion, and (b) is an enlarged view of a portion indicated by symbol A in (a).

FIG. 4 is a plan view showing a situation where a wire saw is passed through a through hole of a hearth brick.

FIG. 5 is a view showing a situation in which the furnace bottom brick layer and the solidified material layer after cutting are integrally carried out of the furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Furnace bottom brick layer 2 Solidified material layer 3 Iron shell 4 Prop 5 Lift jack 6 Blast furnace foundation 7 Wire saw 8 Through hole 9 Metal fitting 10 Position higher than upper surface of solidified material layer 11 Moving direction 12 Work floor 13 Dolly 14 Dolly stand 15 Heavy construction equipment

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroya Marushima 1 Kawasaki-cho, Chuo-ku, Chiba Kawasaki Steel Works Co., Ltd. (72) Keiji Matsuda 1-Kawasaki-cho, Chuo-ku, Chiba Kawasaki Steel Co., Ltd. Inside the steelworks

Claims (3)

[Claims] When the blast furnace is blown off and the solidified layer and the bottom brick layer remaining at the furnace bottom are carried out of the furnace and removed, the furnace body of the blast furnace is horizontally moved at a position higher than the solidified layer. After cutting, the furnace body above the cutting position is suspended and fixed by the blast furnace column as it is, the furnace shell below the cutting position is removed over the entire circumference of the furnace body, and the solidified material layer and the bottom brick are removed. A method for dismantling the bottom of a blast furnace, comprising: 2. The furnace bottom brick layer is cut horizontally with a wire saw along the bottom thereof to separate it from the blast furnace foundation, and is drawn out of the furnace with the solidified layer placed thereon. A method for dismantling a blast furnace bottom according to claim 1. 3. The furnace bottom brick layer is drawn out by using a horizontal pulling means, a bogie, and a dolly mount.
Or the disassembly method of the bottom part of a blast furnace described in 2.