JPH03291319A - Method for removing residual pig and refractory brick in blast furnace - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for dismantling and removing residual pig iron and refractory bricks in the furnace when renovating an aging blast furnace.

(Prior art) The hearth and walls of a blast furnace have a structure in which an iron shell, a stave cooler, and refractory bricks are sequentially laminated from the outside. , it is necessary to carry out its repair work periodically.

During this refurbishment, hot metal remains at the bottom of the furnace and becomes residual pig iron, so this residual pig iron is cooled and solidified prior to the refurbishment. )
The tensile strength is 2,000 to 3,000 kg/cj, and the compressive strength is even higher, making it extremely difficult to remove.

For this reason, blasting has traditionally been used to dismantle the residual pig iron, but currently, blast holes are drilled while melting the residual pig iron using a flame jet lance. It is.

Specifically, as shown in Fig. 16, first, the steel skin and stave cooler (a) from a part of the lower side wall of the blast furnace are removed to create an opening (b). Remove the refractory bricks and the refractory brick parts surrounded by the iron shell on both sides of the opening (b) (C) and remove a part of the residual pig iron (e) surrounded by the refractory bricks (a). By exposing it, a free surface (f) for blasting is formed (Fig. 17), and after being exposed,
Pig residue (e) using a flame jet lance (not shown)
A blasting hole (not shown) is drilled in the free surface of the hole, gunpowder is loaded into the blasting hole, and then blasted to destroy the residual pig iron forming the free surface, and the residual pig iron waste is discharged. After that (Fig. 18), remove the appropriate circumferential portion of the refractory brick (A) between the iron skin (a) and the residual pig iron (C), and then remove the residual pig iron (e).
), the remaining pig iron and refractory bricks are dismantled by repeating the process of blowing, destroying, and discharging (Figures 19 and 20).

At this time, the iron shell and stave cooler (a) are used as protection to prevent residual pig iron (e) from scattering outside the furnace due to blasting.

(Problem to be solved by the invention! However, according to the above conventional method, when drilling a blasting hole by melting residual pig iron with the flame of a jet lance, if the hot metal is not discharged, the hole will be formed. Therefore, the drilling angle must be turned upward to allow the hot metal to flow out naturally. Therefore, the drilling form of the blast hole is limited and it is difficult to find the hole at the optimal angle for blasting the residual pig iron. There may be cases where drilling is not possible.

Furthermore, the flame emitted from the jet lance is extremely dangerous and not only causes problems in workability, but since the hole is drilled while melting the residual pig iron, it is difficult to obtain a uniform hole diameter. In addition, it is difficult to drill a straight hole, which makes loading the gunpowder time-consuming and reduces blasting efficiency.

In addition, in the above conventional method, the refractory brick (e) is partially removed to form a free surface (f) for blasting, and then the blasting is performed. Not only is it necessary to find and crush weak parts, but during blasting, lumps and fragments of residual pig iron are scattered in all directions and directly collide with the stave cooler (a), causing damage to the stave cooler and the need to replace it with a new one. The problem arises that this is not the case.

The present invention aims to solve these problems and provide a method that can efficiently dismantle and remove residual pig iron and refractory bricks while preventing damage to stave coolers and the like.

(Means for Solving the Problems) In order to achieve the above-mentioned object distantly, the method for removing residual pig iron and refractory bricks from a blast furnace of the present invention includes removing iron skin and refractory bricks from a part of the lower side wall of the blast furnace, After making a partial opening, a blasting hole is drilled in the residual pig iron exposed at the opening using a rotary drill, and an appropriate amount of gunpowder is loaded into the blasting hole and detonated, thereby surrounding it with fireproof bricks. After part of the residual pig iron is destroyed, the residual pig iron is discharged from the opening to the outside of the furnace, and this residual pig iron destruction and discharge work is repeated to dismantle the residual pig iron surrounded by the refractory bricks, and then the refractory bricks are dismantled. It is characterized by its removal.

(Operation) After removing part of the iron skin and refractory bricks from a part of the lower side wall of the blast furnace to expose a part of the residual iron deposited and solidified at the bottom of the blast furnace, a blast hole is drilled with a rotary drill. Since it is a material, it can be drilled safely and efficiently, and the drilled holes are straight and have a constant diameter, so that all holes are drilled uniformly and accurately.

Therefore, the blasting can be easily and reliably loaded into the blasting hole, making it possible to carry out core blasting and controlling the direction in which the residual pig iron shear is scattered due to the blasting.

Furthermore, since the residual pig iron is removed without leaving the refractory bricks, the stave cooler installed inside the steel shell is covered and protected by the refractory bricks, so that even though the residual pig iron is removed, , there is no risk of damage.

Furthermore, since the refractory bricks are removed after the residual pig iron is removed, the demolition and removal work can be carried out efficiently.

(Example) To explain the example of the present invention with reference to the drawings, the blast furnace (])
As is well known, the furnace wall is made up of iron g' (2) and a stave cooler (2) with cooling pipes stretched in a lattice pattern from the outside.
3) The stamp material (3a) and the refractory brick (4) are sequentially laminated to form the bottom of the tank (Figures 1 and 2).

When this blast furnace (1) is old and needs to be renovated, first, the steel shell (2), stave cooler (3), and refractory bricks (4) of a part of the lower side wall of the blast furnace (1) are mechanically destroyed. to open a part of the side wall (5) and expose a part of the outer periphery of the residual iron (6) deposited and solidified at the bottom of the blast furnace (
Figure 3).

Note that the residual pig iron (6) is appropriately cooled and solidified prior to dismantling.

Next, blast holes (8) are drilled at a plurality of locations on the exposed surface of the residual pig iron (6) using a drilling device (7) (FIG. 4).

As shown in Fig. 1O, this drilling device (7) has a moving table 0υ arranged in a mounting guide 00) so as to be movable back and forth, and a cutting bin (9a) is integrally provided at the tip of the moving table aO. It is made by rotatably supporting a rotary drill (9).
This rotary drill (9) is driven by a rotary drive electric motor Q'Zj installed on a moving table (11), and is hung between a toothed pulley fixed to the rotation shaft of the electric motor 0 and the rear end of the drill (9). is rotated via a passing belt 03).

Further, a fluid supply hole (not shown) is provided at the tip of the rotary drill (9a), which is hollow and is cut from the rear end surface.

Furthermore, the drive mechanism of the moving table OD is configured to move from the guide 0(1) to the guide 0(1).
A screw rod circle is rotatably supported between the front and rear of the screw rod (
Screw (b) into the moving table 0υ and guide the screw (b) to 0
By rotating the feed motor OS installed on the rear end of ω, the moving table 0υ is threaded along the screw rod circle.
It is designed to be able to be screwed back and forth.

Note that it is preferable that the movable table 00 is placed at the bottom of the tank so that it can be quickly retreated using an appropriate quick return mechanism.

The drilling device (7) with the bottom of the tank in this way has its guide 0@
is arranged and fixed on the elevating arm σ of a movable dolly 00 such as a crawler dolly, and the movable dolly 0ω is operated to move to the position of drilling the blast hole in the residual pig iron (6).

Drill (9) toward the residual pig iron (6) at that position.
(9a) close to the electric motor 02105
1, the drill (9) is rotated by the rotary driving electric motor 11G21 at a constant rotational speed that is used for cutting the residual pig iron (6), and the screw rod 041 is rotated by the feeding electric motor 1!05). The movable table (11) screwed onto the screw rod 041 moves forward and removes the cutting pit (9a) from the residual pig iron (6).
The remaining pig iron (6) is moved forward at a constant speed suitable for cutting.
Drill a hole in the hole.

During this drilling, if fluid such as high pressure air, pressure water or pressure oil is supplied from the rear end of the drill (9) to the fluid supply hole inside the drill, the fluid will flow into the drilling hole from the tip of the cutting pit (9a). The remaining pig iron is ejected from the hole and flows toward the hole opening side through the gap between the drill body (9) and the hole wall, thereby discharging the cutting residue from the hole.

When the blast hole (8) of the desired depth is drilled in the pig iron residue (6),
Next, the drill (9) is removed from the hole.

Thereafter, the rotary drilling device is moved to the next drilling position and drilling is performed again in the same manner as described above.

After blasting holes (8) of a desired depth are drilled at a plurality of locations in the residual pig iron (6) in this manner, explosives are loaded into the blasting holes (8). At this time, the blast hole (8) is cut by the cutting bit (9) of the drill (9).
9a), the hole is formed to have a constant diameter over its entire length and is straight, so that gunpowder can be loaded easily and accurately.

After loading the gunpowder, it is blasted to destroy a part of the residual pig iron (6), and the crushed pig residue is discharged (Fig. 5).

In this way, after forming the demolition part 0 mark by core blasting toward the center of the blast furnace (1), blow blasting is performed on the demolition part side to widen the demolition part side (FIG. 6).

At this time, the refractory bricks (4) that extend on both sides of the opening (5)
The residual pig iron part surrounded by the inner peripheral surface of the hole is destroyed, and the opening (5
) The firebrick parts on both sides are exposed.

Next, the dismantled section (18a
) is exposed in the blast hole (6) in the same manner as above.
The remaining pig iron (6) is destroyed by drilling a hole (8), loading gunpowder and performing core blasting.
5) and then discharged to the outside through the dismantled part (18b)
Perform blasting and cut and spread the residual pig iron (6) to the inner circumferential surface of the refractory brick (4) (Fig. 7.8).

In addition, during the above blasting, the destroyed pig iron (6) is scattered, but the stave cooler (3) is
Since the stave cooler (3) is covered and protected, there is no risk of damage to the stave cooler (3).

In this way, the residual pig iron (6) surrounded by the refractory bricks (4) is completely removed by repeatedly destroying it by blasting from the opening (5) side toward the center and discharging the residual pig iron. After that, the firebricks (4) are dismantled and removed using an appropriate demolition machine (Figure 9).

In the above embodiment, the opening (5) is connected to the blast furnace (1).
) was installed at one place on the lower side wall of the blast furnace (1) to destroy and discharge the residual pig iron (6).
The remaining pig iron (6) may be dismantled and discharged by the same operation as above, after core removal is performed from these openings (5) (5) in the lower side walls toward the center. According to the above, it is possible to dismantle and remove iron residue and refractory bricks with high efficiency.

〔Effect of the invention〕

As described above, according to the method for removing pig iron residue and refractory bricks from a blast furnace of the present invention, after removing the iron shell, stave cooler and refractory bricks from a part of the lower side wall of the blast furnace and opening a part of the side wall, the A blast hole is drilled in the residual pig iron exposed at the opening, and an appropriate amount of gunpowder is loaded into the blast hole and detonated to destroy a portion of the residual pig iron surrounded by firebricks. After the residual pig iron is discharged from the opening to the outside of the furnace, and this residual pig iron destruction and discharge work is repeated to break up the residual pig iron surrounded by refractory bricks, the refractory bricks are dismantled and removed. After removing part of the iron shell and refractory bricks from the lower side wall to expose a part of the residual pig iron that has accumulated and solidified at the bottom of the blast furnace, a blast hole is drilled with a rotary drill, so the blast hole is exposed to dusty and high temperatures. Despite the working environment, it is possible to drill holes safely and efficiently, and the direction of the hole can be freely set to the optimal angle for blasting.Furthermore, the drilled hole is straight and has a constant diameter. All the holes are drilled uniformly and with high precision, making it possible to load blasting into the blast holes easily and reliably, and also being able to control the direction of the scattering of residual pig iron by blasting, making it possible to destroy the residual pig iron accurately. It is something.

Furthermore, since the residual pig iron is removed by blasting while the refractory bricks remain, the stave cooler installed inside the steel shell is covered and protected by the refractory bricks, making it possible to destroy the residual pig iron. Nevertheless, there is no risk of damage and it can be used as is, making it extremely economical.

Furthermore, since the refractory bricks are removed after the residual pig iron is removed, the dismantling and removal work can be carried out efficiently, and the period for repairing the blast furnace can therefore be significantly shortened.

[Brief explanation of the drawing]

Figures 1 to 15 show examples of the present invention. Figure 1 is a simplified sectional view of the blast furnace, Figure 2 is a partially enlarged sectional view of the lower side wall, and Figures 3 to 9 are disassembled. FIG. 10 is a side view of a mobile cart equipped with a drilling device; FIGS. 11 to 15 are simplified cross-sectional views showing another dismantling process of the method of the present invention; FIG. 16 is a simplified cross-sectional view showing the process; 20 to 20 are simplified cross-sectional views showing the conventional dismantling process. (1)...Blast furnace, (2)...Iron shell, (3)...Stave cooler, (4)...Refractory brick, (5)...
Opening, (6)...residue, (9)...rotary drill,
Side (18a) (18b)...Disassembly section.

Claims (1)

[Claims] (1) After removing part of the iron shell, stave cooler and refractory bricks from the lower side wall of the blast furnace and opening a part of the side wall, a blast hole is drilled in the residual pig iron exposed in the opening using a rotary drill. By loading an appropriate amount of gunpowder into the blast hole and detonating it, a portion of the residual pig iron surrounded by refractory bricks is destroyed, and then it is discharged from the furnace through the opening, and this residual pig iron destruction and discharge work is carried out. A method for removing residual pig iron and refractory bricks from a blast furnace, which comprises repeatedly dismantling the residual pig iron surrounded by refractory bricks, and then dismantling and scattering the refractory bricks.