JPS5935556Y2 - Blast furnace bottom and furnace wall structure - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a protective wall structure for the wall and bottom of a blast furnace constructed of graphite bricks.

In recent years, as blast furnaces have become larger, operations have become more demanding due to higher internal pressure and higher air temperature, and the cooling method for blast furnaces has also been improved from a water-cooled box method to a stave cooler type, which provides uniform cooling and has a good cooling effect. As a result, graphite bricks with high thermal conductivity and excellent cooling effect can be used even at high temperatures, allowing them to flow from the bottom of the furnace to the sump.
It tends to be used a lot on morning glories and hearth bellies.

However, it has been confirmed that graphite bricks also suffer from peeling due to the infiltration of hot metal and slag through the pores, and furthermore, the joints of graphite bricks are markedly penetrated by hot metal, and it has also been confirmed that joint erosion has occurred due to the infiltration of alkali. There is.

Conventionally, a protective wall made of clay bricks was installed inside the graphite brick furnace to protect the graphite bricks from oxidation and thermal shock in the early stages of operation, but this protective wall was only used in the early stages of operation and could easily peel off. The graphite bricks suffered from the above-mentioned wear and tear from the early stage of operation, and the boundary between the furnace wall and the furnace bottom was abnormally eroded.

In order to solve these problems, the present invention is based on carbonized bricks, which are more expensive than graphite bricks but are economically reliable when used as protective walls, and have less penetration of hot metal and slag. We have developed a structure in which a protective wall is constructed using siliceous bricks and silica carbide mortar during operation between the graphite bricks used for the walls and bottom of the blast furnace and the clay brick protective wall. be.

Instead of the silicon carbide bricks and silicon carbide mortar described above, the protective wall during operation may be constructed using high alumina bricks and high alumina mortar.

The present invention will be explained below with reference to the drawings.

As shown in FIGS. 2 and 4, a flotation prevention taper (arrow 1
0 direction), and on the back surface 4 of the silicon carbide brick or high alumina brick 3, an upward anti-floating taper (in the direction of arrow 10) corresponding to the above-mentioned flotation-preventing taper is attached, pointing upward toward the blast furnace center axis 9. Front side 2 and back side 4 with anti-floating tapers of each brick 1 and 3 respectively
Together, a protective wall is constructed using silicon carbide bricks or high alumina bricks 3 on the inside of the furnace of graphite bricks 1, and silicon carbide mortar or high alumina mortar at the joints.

Then, a protective wall made of clay bricks 5 is constructed inside the furnace of the protective wall made of silicon carbide bricks or high alumina bricks 3.

Further, as shown in FIG. 3, the joints 6 of the graphite bricks 1 are completely covered by silicon carbide bricks or high alumina bricks 3.

The protective wall of the clay brick 5 plays its role in the early stages of operation as in the past and is quickly lost, but the graphite brick 1 is tightly engaged with the silicon carbide brick or high alumina brick 3 due to the antifloating taper. protected by a protective wall.

When the operation continues and the silicon carbide bricks or high alumina bricks 3 are worn out, the graphite bricks 1 do not show an abnormal residual lining curve 7 as shown in Figure 1, but show a normal residual lining curve. It wears out while showing 8.

In this way, with this invention, the boundary between the furnace wall and the furnace bottom of the blast furnace will no longer be abnormally eroded, and the furnace will wear out while showing a normal balanced residual lining curve, extending the furnace life. It turns out.

[Brief explanation of drawings]

FIG. 1 is a partial vertical cross-sectional view of a conventional blast furnace, FIG. 2 is a partial vertical cross-sectional view showing an example of the protective wall structure for the furnace wall and bottom of the blast furnace according to the present invention, and FIG. FIG. 4 is a sectional view showing an engaging portion of a silicon carbide brick or a high alumina brick according to the present invention. In the figure, 1 is a graphite brick, 2 is the front inside of the furnace of graphite brick 1, 3 is a silicon carbide brick or high alumina brick, and 4 is a silicon carbide brick or high alumina brick 3
, 5 is a clay brick protective wall, 6 is a graphite brick joint, 7 is an abnormal residual lining curve of the conventional example, 8 is a normal residual lining curve according to the present invention, 9 is a blast furnace center axis, and 10 is a The arrow 11 indicates the direction of inclination of the float prevention device and the furnace shell.

Claims (1)

[Scope of utility model registration request] In the hearth bottom and furnace wall constructed of graphite bricks 1, a protective wall is constructed on the inside of the furnace with silicon carbide bricks or high alumina bricks 3, and the inner front surface 2 of the graphite bricks 1 in contact with the furnace inner side and the silicon carbide Quality brick or high alumina brick 3
The bottom and wall structure of a blast furnace are characterized by an upward taper toward the central axis 9 of the blast furnace, which corresponds to the back surface 4 of the furnace.