JPS63279092A - Molten metal vessel - 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 (Fields of Application of FI) The present invention is applicable to molten metal containers (hereinafter referred to as "molten metal containers") such as metal smelting furnaces, smelting furnaces, or coal gasification furnaces using metal baths. The present invention relates to molten metal containers which are effective in preventing or reducing furnace wall melting damage, and which are equipped with means for more effectively forced cooling of the boundary between the molten slag phase and the molten metal phase.

(Prior Art) It is known to use some kind of forced cooling block above the surface of the molten slag phase in a molten metal container, as close as possible to the surface of this slag phase (for example, Japanese Patent Publication No. 57-35389). (see official bulletin).

However, in the above-mentioned molten metal container, not only the upper part corresponding to the gas phase from the surface of the molten slag phase but also the area from the upper part of the molten slag phase surface to the lower part of the part equivalent to the molten metal phase surface Reducing or preventing melting of refractories over a wider range in the vertical direction remains a major challenge from the perspective of extending furnace life and reducing refractory costs.

As a means to solve this problem, in the field of copper smelting,
It is known to perform forced cooling to a portion corresponding to the lower part of the surface of the molten metal phase. For example, "Product Technical Report" 27.19
December 1983, pages 1 to 16, shows an example of using a forced cooling block of a water cooling jacket in a portion corresponding to the slag line. On the other hand, in the fields of iron smelting and iron bath coal gasification,
As a more active cooling method, for example, Utility Model Application No. 53-1211
Publication No. 11 describes a water-cooled converter with all iron skins, published in Japanese Patent Application Laid-Open No. 58-171.
No. 482 discloses a heat pipe cooling means that focuses on the adhesion of a solidified metal (or slag) layer, and is further disclosed in Japanese Patent Application Laid-Open No. 61-1
Japanese Patent No. 23697 proposes a method in which a forced cooling block is applied directly to the boundary between the molten metal and slag phases.

However, when trying to apply the above-mentioned technology, which is fully matured in W4 smelting, or the above three proposals, etc. to the field of molten metal containers that actually contain molten iron, especially when the processing temperature is high, 1650℃ Because it can reach a certain degree,
In terms of the refractory material in front of the forced cooling block, or the erosion resistance and long-term reliability of the block, the technology has not yet reached the level of practical use, especially when cooling below the surface level of the molten metal phase. The main reason for this can be considered to be insufficient cooling capacity due to so-called unidirectional cooling of the forced cooling block.

In addition, as a completely separate technique, Japanese Patent Application Laid-Open No. 60-58487 discloses that in the case of a so-called top-blown iron bath coal gasifier, the diameter of the furnace in the region in contact with the gas phase is expanded to reduce the amount of high-temperature slag that is scattered. It has been proposed to protect the refractories by avoiding contact with the furnace wall refractories as much as possible, but even in this case, the focus is still on the protection of the furnace wall in the gas phase. remains.

(Problems to be Solved by the Invention) These known inventions have a structure in which forced cooling blocks are arranged vertically in a wide area ranging from a portion corresponding to the gas phase to a portion corresponding to the lower part of the surface of the molten metal phase. In both cases, the operating surface of the forced cooling block is aligned vertically along the container wall.

Therefore, in the past, cooling blocks under the surface of the molten metal phase could only be expected to have a so-called unidirectional cooling effect, and even under conditions with minimal agitation of the bath, the molten metal, which has good thermal conductivity, could be directly cooled. It is constantly subjected to very high heat flux. For this reason, in the vertical operating planes mentioned above, it is difficult to form any so-called surface coating layer, which is generally essential for the protection of known high-performance forced cooling blocks, and such cooling blocks are always subject to erosion and destruction. The furnace life and reliability are not sufficient.

Even in the case of a structure in which a highly thermally conductive refractory is placed on the surface of the cooling block, this type of danger can occur due to corrosion of the refractory or spalling caused by contact with slag due to bath vibration. Phenomena such as reduction in size and penetration of molten metal into cracks are unavoidable; 1. exists as well.

Thus, the object of the present invention is basically to
- To provide a means for preventing or reducing melting damage of the wall corresponding to the so-called slag line vicinity of a molten metal container, which improves the means disclosed in No. 123697 and No. 60 to No. 58487, and has higher safety and reliability. be.

(Means for Solving the Problems) Here, the present inventors have developed a cooling block by constantly causing a thin solidified phase to adhere to the surface of the forced cooling block that comes into contact with the molten metal phase. The inventors have focused on the fact that the beams can be completely protected, thereby advantageously solving the above-mentioned problems, and have found a means to achieve this, thereby completing the present invention.

Therefore, the present invention provides a molten metal container for storing molten metal and molten slag, in which a container wall portion in a region touching a boundary line between a molten slag phase and a molten metal phase stored in the molten metal container is provided. A sloped portion with a gentle downward slope toward the inside, a forced cooling block disposed in a part of the sloped portion, and, if necessary, a region adjacent to the sloped portion in contact with the molten slag phase and/or the gas phase. This molten metal container is characterized in that it is equipped with a forced cooling block disposed on at least a portion of the container wall.

Here, the molten metal container has already been mentioned. The installation position of the inclined part may be such that the boundary line between the molten slag phase and the molten metal phase to be accommodated is located at the lowest possible position of the inclined part, and the degree of the inclination is also determined. There is no particular limitation as long as a self-coating film, which will be described later, is formed.

The idea is to increase the cooling effect by bringing a wider cooling surface into contact with a smaller layer of molten metal or slag.

Note that the forced cooling block is already known, and a water-cooled copper jacket is exemplified, but it is not limited to a specific one.
A highly thermally conductive refractory layer may be provided on the surface.

Thus, according to the present invention, the above-mentioned prior art 1
The main problems of can be solved by the means described below.

First, the basic vessel shape is such that a cooling block similar to that of a conventional vertical or arcuate furnace wall is placed on a portion of the gently sloped section, if desired.

Next, the surface position of the molten metal phase is maintained at the lowest possible position in the cooling block of the inclined part, and the contact between the cooling block and the molten metal phase is kept as small as possible within the range of a thin layer,
Reduce high heat flux loads.

That is, the unidirectional cooling effect of the cooling block is sufficiently exerted on the thin layer of the molten metal phase, while preferably
The molten slag phase near the wall is configured to be cooled in two directions, where it is also affected by cooling from other cooling blocks provided on the furnace wall adjacent to the sloped portion.

By such means, a very thin solidified phase of molten metal or slag, a so-called self-coating film, is formed on the surface of the cooling block, making it possible to completely protect the surface and the entire cooling block. Such a solidified layer consists of molten metal and/or molten slag.

A gas phase exists above the molten slag phase, and a cooling panel may be provided on at least a portion of the furnace wall portion in contact with the gas phase, if necessary.

This type of high-performance forced cooling block that comes into direct contact with relatively high-temperature molten slag/metal may be a water-cooled*m jacket as described above, for example, as water-cooled steel NwI type in the field of continuous steel casting technology. Any known material may be used.

(effect) The invention will now be further described with reference to the accompanying drawings.

FIG. 1 shows a molten metal container according to the present invention, in which a similar forced cooling block is also arranged in the furnace wall part that is in contact with the molten slag phase, and a water cooling panel is also arranged in the furnace wall part that is in contact with the gas phase. FIG.

Inside the molten metal container, from the top, there are gas phase 1, molten slag phase 2,
A molten metal phase 3 is present, and the molten metal container according to the present invention is provided with an inclined portion 4 in a portion corresponding to a region in contact with the boundary region between the molten slag phase and the molten metal phase. By forming the sloped part, the contact between the molten metal, which provides a higher heat flux load, and the cooling block is minimized and kept within the range of a thin metal phase, thereby promoting unidirectional solidification of the molten metal as quickly as possible. . A cooling block 6 is provided on the inclined portion 4, and a thin solidified layer 5, shown in black in the figure, is formed on the upper surface of the cooling block 6.

In a preferred embodiment of the present invention, a forced cooling block 6 is also provided on the upper furnace wall adjacent to the inclined portion 4, which enables two-way solidification of the molten slag and prevents the formation of the solidified layer. Formation is greatly promoted.

At the other end of the inclined portion 4, a furnace wall is constructed of ordinary refractories 7, and these may be of a known form.
A water-cooled panel 8 is provided on the furnace wall portion in contact with the gas phase, and the outside thereof is covered with an iron skin 9 with a refractory 7 interposed therebetween.

FIG. 2 is a partial cross-sectional view of the same, showing an example of application to a pressurized or depressurized container. The same members as in Fig. 1 are indicated by the same reference numerals, and except that the furnace wall surface is spherical, it is substantially the same as in Fig. 1.For the explanation of the structure, that of Fig. 1 will be referred to, and further explanation will be given. omitted.

In the case of this type of pressure-resistant vessel shown in Figure 2, it is difficult to create a complex furnace shape as shown in Figure 1 due to the required characteristics of the shell, and it is generally spherical, cylindrical, or close to this. The shape is adopted. Therefore, it is necessary to appropriately arrange the cooling block 6 and the refractory 7 inside the steel shell 9, but the present invention can be easily applied to any container shape.

In addition, during the initial operation of these furnaces or vessels, and during operation, direct contact between the molten phase and the forced cooling block should be avoided.
If contact is to be avoided: 7°.' It is also possible to use a known device in which some kind of refractory material is placed on a part or all of the surface, and these also fall within the scope of the present invention.

In the case of so-called top-blown iron bath coal gasification, because its main purpose is that it does not require strong stirring of the bath as in metal refining reactions, the bath surface, especially the area near the container wall, is relatively quiet. The refractory on the furnace wall, which corresponds to the molten metal phase, hardly suffers from melting damage, but the container wall above the boundary between the molten slag and metal is damaged by the accumulated slag and high-temperature flying slag. As a result, the furnace wall suffered significant corrosion damage, and unless a forced cooling block was applied to the furnace wall, it was difficult to achieve a service life of more than about one month, no matter how high-quality and thick the refractory was. However, when the arrangement shown in Fig. 2 was applied to the vertical furnace wall of a vertical cylindrical converter according to the present invention, the desired solidification phase adhered and there was almost no melting damage in the cooling block. As a result, the furnace life is expected to be extended by about one year.

In addition, when a gasification furnace is used as a smelting reduction furnace for iron ore, which requires strong stirring of the bath, at an iron bath temperature of approximately 1600°C, it is necessary to avoid excessive bottom-blown stirring gas, appropriately select the bath area, and Measures such as injecting coke and lump quicklime near the furnace wall have suppressed bath surface vibration near the furnace wall, making stable operation with a long life possible.

(Effects of the Invention) As described above, the present invention is highly effective in extending the so-called slag line life of the molten metal container and reducing the cost of refractories. It is also effective in the fields of arc-heated containers and steel-grained blast furnaces. Even in this case, it goes without saying that a gas phase forced cooling block (panel) is not necessarily required.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a molten metal container according to the present invention;
and FIG. 2 is a partial sectional view showing an example of application to a pressurized or depressurized container. 1: Gas phase 2: Molten slag phase 3: Molten metal phase 4: Inclined portion 5: Solidified phase 6: Cooling block 7: Refractory
8: Cooling panel 9: Iron skin

Claims (2)

[Claims] (1) A molten metal container that stores molten metal and molten slag, in which a wall portion of the molten metal container is placed in a region that is in contact with the boundary line between the molten slag phase and the molten metal phase stored in the molten metal container. A slope with a gentle downward slope,
A molten metal container comprising an accentuated cooling block disposed on at least a portion of the slope. (2) A molten metal container containing molten metal and molten slag, in which a wall portion of the molten metal container is placed in a region touching a boundary line between a molten slag phase and a molten metal phase stored in the molten metal container toward the inside of the container. A slope with a gentle downward slope,
a forced cooling block disposed on at least a portion of the slope;
A molten metal container further comprising a forced cooling block disposed on at least a portion of the container wall adjacent to the inclined portion in a region in contact with the molten slag phase and/or the gas phase.