JPH07151474A - Method and device for removing sticking matter to molten metal vessel - Google Patents

Abstract

PURPOSE:To quickly remove sticking matters to a molten metal vessel and accessory equipment thereof. CONSTITUTION:A fuel is jetted from a fuel injection pipe 4 and oxygen from an inner pipe 2 of a double pipe located at the center inside the fuel injection pipe 4, while a mixture of iron powder and lime, the iron powder and silica, the iron powder and silicon, the silicon and the lime or others is jetted as a powder flux from a gap between the inner pipe 2 and an outer pipe 3. Thereby sticking matters of a molten metal vessel are removed. Accordingly, ore, slag, etc., sticking to the molten metal vessel and accessory equipment thereof can be removed completely in a short time irrespective of temperature and a state of sticking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for removing ingots, slag and the like adhering during operation in a molten metal container and its auxiliary equipment.

[0002]

2. Description of the Related Art Molten metal containers such as converters, ladles and torpedo, and their ancillary equipment have deposits of ingots, slag, etc. during operation, and other equipment when charging raw materials and moving molten metal containers It is a cause of contact troubles and various other problems. As a method for removing deposits from the molten metal container and its ancillary equipment, a method is generally used in which oxygen is sprayed onto the surface of the deposits using an iron pipe, and the reaction heat of the deposits raises the temperature to a high temperature to cause a melt flow. It is being appreciated. However, when the temperature of the deposit is high, it acts as an ignition source, but when the temperature of the deposit is low, or when there is no reaction heat such as slag, it should be melted and removed. Is impossible. There is also a method of removing the deposit from the base metal surface by applying a mechanical impact force to the deposit, but if the deposit and the base material are firmly attached, Not only is it difficult to peel off and remove the adhered matter with only a specific impact force, but also the refractory material of the base material may be peeled off, which is not preferable.

As another method, fuel is injected from the fuel injection tube, metal powder is injected from the inner tube of the double tube arranged in the center of the fuel injection tube, and oxygen is injected from the outer tube to remove deposits from the molten metal container. Method (Japanese Patent Laid-Open No. 2-287092),
A guide tube with an umbrella-shaped collar, which is composed of an inner tube and an outer tube having a water-passing structure arranged around the inner tube, and which is screwed to the tip of the inner tube, and a tip of the outer tube that surrounds the guide tube. It is equipped with a burner lid connected by connecting a plurality of circumferences, and the fuel gas introduced from the inner tube is reversed between the guide tube and the burner lid, and the oxygen introduced from between the inner tube and the outer tube is A slit burner (actual flat blade 3) having a gas injection port that is inverted between the outer tube and the guide tube and is mixed and injected downward.
-85455 gazette) etc. are proposed.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the method disclosed in Japanese Patent No. 092, since the metal powder is ejected from the inner tube of the double tube, the metal powder is deposited on the deposits, and the reaction of the metal powder does not contribute to all the reaction, so that it takes time for the melt flow. It costs. Further, this method aims at raising the temperature by the metal powder, but when the deposit is slag having a high melting point, the melt flow rate is slow with the metal powder. Further, since oxygen is injected into the gap between the inner pipe and the outer pipe, there is a drawback that the melted deposits are suppressed from scattering and the deposits flow rate is slowed. Further, the slit burner disclosed in Japanese Utility Model Laid-Open No. 3-85455 is to insert metal into the communication hole of the molten metal container from below and raise and lower it to remove the adherent metal on the inner wall of the communication hole. Not only cannot it be applied to the adherent metal, but since the adherent metal is melted by the combustion heat of the fuel gas, the melt flow rate becomes slow when the deposit is a high melting point slag.

An object of the present invention is a method for removing deposits on a molten metal container, which allows rapid removal of deposits regardless of the composition and temperature of deposits on the molten metal container and its associated equipment, and on the shape of the deposit. And to provide a device.

[0006]

[Means for Solving the Problems] The present inventors have conducted various test studies in order to achieve the above object. As a result, in order to melt and remove the deposits on the molten metal container and its associated equipment with a burner, it is necessary to raise the temperature of the deposits and lower the melting point of the deposits. Oxygen is used to raise the combustion temperature in order to raise the temperature of the deposit, but reaction heat (combustion heat) due to metal powder such as iron powder and silicon is necessary for further raising the temperature. On the other hand, when the deposit is slag, the slag has a high melting point, and it is difficult to remove the melt stream only by increasing the temperature. For example, the melting point of Al ₂ O ₃ is 2020 ° C., and melting removal with a burner is impossible. Therefore, if the deposit is slag, it is necessary to lower the melting point. For example, in the case of alumina slag, as shown in FIG. 5, the melt flow rate is slow only with metal powder, but in addition to the above metal powder, lime and silica powder. In combination with the lowering of the melting point by the powder flux, the melt flow rate can be made 2 to 3 times as high as that of the iron powder alone, and the deposit can be quickly removed by the melt flow. In addition, a double tube that injects oxygen from the inner tube and powder flux from the gap between the inner tube and the outer tube is placed in the center of the fuel injection tube, and the fuel and oxygen ejection holes are surrounded around the powder flux ejection port. By installing it, the reaction and scattering of the powder flux is promoted by the oxygen from the inner tube, the temperature of the deposit is raised by the fuel and oxygen around the outside of the powder flux jet outlet, and the deposit is quickly removed. The present invention has been achieved by investigating that it is possible.

That is, according to the present invention, fuel is supplied from the fuel injection pipe, oxygen is supplied from the inner pipe of the double pipe arranged in the center of the fuel injection pipe, and iron powder, lime and iron powder are used as powder flux from the gap between the inner pipe and the outer pipe. And a silica, iron powder and silicon, a mixture of silicon and lime, etc. are ejected to remove the deposits on the molten metal container.

Further, a double pipe for injecting oxygen from the inner pipe and powder flux from the gap between the inner pipe and the outer pipe is arranged in the center of the fuel injection pipe, and the fuel and oxygen are ejected to the outer periphery of the powder flux ejection port. It is an apparatus for removing deposits on a molten metal container, characterized in that holes are provided around it.

[0009]

In the present invention, fuel and oxygen are supplied from the fuel injection pipe, oxygen is supplied from the inner pipe of the double pipe arranged in the center of the fuel injection pipe, and iron powder and lime are used as powder flux from the gap between the inner pipe and the outer pipe. By ejecting a mixture of iron powder and silica, iron powder and silicon, silicon and lime, etc. to remove the deposits in the molten metal container, the oxygen ejected from the inner pipe promotes the reaction and scattering of the deposits. The powder flux ejected from the gap between the pipe and the outer pipe raises the temperature and lowers the melting point of the deposit, and the combustion heat of the fuel and oxygen ejected from the outer periphery heats the deposit at high temperature. Due to the effect, the deposit can be quickly removed.

Further, in the present invention, a double pipe for injecting oxygen from the inner pipe and powder flux from the gap between the inner pipe and the outer pipe is arranged in the center of the fuel injection pipe, and is provided around the outer periphery of the powder flux ejection port. By surrounding the fuel and oxygen ejection holes, oxygen can be injected from the inner pipe, powder flux can be injected from the gap between the inner pipe and the outer pipe, and fuel and oxygen can be injected from the outer periphery and ejected from the inner pipe. Oxygen promotes the reaction and scattering of the deposits, and the powder flux ejected from the gap between the inner and outer tubes raises the temperature and lowers the melting point of the deposits. By this, since the attached matter is heated at a high temperature, the attached matter can be quickly removed.

In the present invention, the powder flux ejected from the gap between the inner tube and the outer tube of the double tube may be selected in accordance with the property of the deposit on the molten metal container. In the case of aiming, as shown in Table 1, by injecting iron powder and Si powder, 1650 ° C. is increased to 1800 ° C. for iron powder alone and 1900 to 2 for iron powder and Si powder.
At 050 ° C, iron powder and SiO ₂ are 1750 to 1800 ° C.
Can be increased to Also, adhered slag (Al ₂ O ₃ )
If achieving low melting point, as shown in FIG. 3, the iron powder added A from 2020 ° C. to 1150 ° C., the iron powder and SiO ₂
Addition B can lower the melting point from 2020 ° C to 1100 ° C. Further, as shown in FIG. 4, lime and SiO
_{With the} addition of ₂ , the melting point can be lowered from 2020 ° C to 1250 ° C.

[0012]

[Table 1]

[0013]

【Example】

Example 1 Hereinafter, an example of an apparatus for removing deposits on a molten metal container used in the method of the present invention will be described with reference to FIG. FIG. 1 shows an apparatus for removing deposits on a molten metal container used in the method of the present invention. FIG. 1 (a) is a front view and FIG. 1 (b) is a sectional view. In FIG. 1, reference numeral 1 is an apparatus for removing deposits of a molten metal container used in the method of the present invention, in which a double pipe consisting of an inner pipe 2 and an outer pipe 3 is arranged in the center of a fuel injection pipe 4, and a tip of the inner pipe 2 is provided. An oxygen ejection hole 5, a powder flux ejection hole 6 in the gap between the inner tube 2 and the outer tube 3, and an ejection hole 9 connected to the fuel flow passage 7 and the oxygen flow passage 8 around the outer periphery thereof. Oxygen is ejected from the oxygen ejection hole 5 at the tip of the tube 2, powder flux is ejected from the powder flux ejection port 6 at the tip of the gap between the inner tube 2 and the outer tube 3, and fuel and oxygen are ejected from the ejection holes 9 around the outer periphery of the powder flux ejection port 6. Is premixed and ejected.

With the above construction, oxygen is ejected from the oxygen ejection hole 5 at the tip of the inner pipe 2 and powder flux is ejected from the powder flux ejection hole 6 in the gap between the inner pipe 2 and the outer pipe 3, and further the outer periphery thereof. By premixing fuel and oxygen from the fuel flow path 7 and the oxygen flow path 8 of the fuel injection pipe 4 of the above and ejecting them from the ejection hole 9, the oxygen ejected from the oxygen ejection hole 5 at the tip of the inner pipe 2 adheres It is possible to promote the reaction of and the scattering of the melted material.
In addition, by selecting the powder flux ejected from the powder flux ejection hole 6 in the gap between the inner tube 2 and the outer tube 3 according to the property of the adhered substance, it is possible to increase the temperature and lower the melting point of the adhered substance. . Furthermore, the deposits are heated to a high temperature by the combustion heat of the fuel and oxygen that are premixed and ejected from the ejection holes 9 on the outer periphery thereof. Therefore, according to the method and apparatus of the present invention, the deposits can be quickly removed by these synergistic effects.

Example 2 The apparatus 1 for removing deposits on a molten metal container described in Example 1 above.
As shown in FIG. 2, the removal test of the deposit 12 on the ladle 11 was carried out by using. First, as shown in Table 2, propane gas was used as a fuel from the fuel flow path of the deposit removing device 1 to
Oxygen from the oxygen flow path at 0 Nm ³ / hr, 250 Nm ³ / h
It is supplied at r, premixed and ejected from the ejection hole, and the deposit 12 is heated by the combustion flame. Thereafter, as a powder flux, a mixture of iron powder and lime or a mixture of silicon and lime is jetted at 800 g / min from the powder flux jet holes in the gap between the inner pipe and the outer pipe of the deposit removing device 1, The deposit 12 was wrapped, and then oxygen was spouted at 140 Nm ³ / hr from the oxygen spouting hole at the tip of the inner tube to remove the deposit 12 by melt flow. Removal time in that case,
The removal amount and removal temperature were measured. The results are shown in Table 2. For comparison, an iron pipe is used to supply oxygen of 250 Nm.
^The deposit 12 was sprayed at a rate of ³ / hr to remove the deposit 12 by melt flow. In that case, the removal time and the removal amount were measured.
The results are shown in Table 2. In addition, "iron powder + lime" in Table 2
Of iron powder 600 g / min, lime 200 g /
min, the mixing ratio of "silicon + lime" is silicon 2
50 g / min and lime 550 g / min.

[0016]

[Table 2]

As shown in Table 2, according to the method of the present invention,
Reaction heat is generated by powder flux and oxygen,
The deposit 12 by the synergistic effect with the combustion flame from the ejection hole
Temperature can be raised, and the deposit 12 can be quickly removed in combination with the lowering of the melting point of the deposit 12 by the powder flux. The removal time is about 1/3 and the removal amount is 3 times that of the conventional method. It has become. As a result, the thickness of the brick at the bottom of the pot can be determined, and a ladle repair plan can be made. In addition, by completely removing the deposits, the decrease in molten steel temperature due to slag during steel receiving was suppressed, enabling stable operation.

[0018]

As described above, according to the present invention,
It is possible to completely remove the metal, slag and the like adhering to the molten metal container and its auxiliary equipment in a short time regardless of the temperature and the adhering condition, and it is possible to reduce the trouble caused by the adhering matter.

[Brief description of drawings]

FIG. 1 shows an apparatus for removing deposits on a molten metal container used in the method of the present invention, in which (a) is a front view and (b) is a sectional view.

FIG. 2 is a conceptual diagram of a ladle adhering matter removal test method in Example 2.

FIG. 3 Iron powder of adhered slag (Al ₂ O ₃ ) and iron powder and S
FIG. 3 is a ternary phase diagram showing a lowering of melting point by adding iO ₂ .

FIG. 4 is a ternary phase diagram showing a decrease in melting point of adhering slag (Al ₂ O ₃ ) by adding lime and SiO ₂ .

FIG. 5 is a graph showing a melt flow rate ratio when an alumina slag is sprayed with a flux of iron powder, iron powder + silica and silicon + lime to cause a melt flow.

[Explanation of symbols]

 1 Adhesion Remover 2 Inner Tube 3 Outer Tube 4 Fuel Injection Tube 5 Oxygen Injection Hole 6 Powder Flux Injection Hole 7 Fuel Flow Path 8 Oxygen Flow Path 9 Injection Hole 11 Ladle 12 Adhesion

Claims (2)

[Claims] 1. A fuel from a fuel injection pipe, oxygen from an inner pipe of a double pipe arranged in the center of the fuel injection pipe, iron powder and lime, iron powder and silica as powder flux from a gap between the inner pipe and the outer pipe, A method for removing deposits on a molten metal container, which comprises ejecting a mixture of iron powder and silicon, or a mixture of silicon and lime to remove deposits on the molten metal container. 2. A double pipe for injecting oxygen from the inner pipe and powder flux from a gap between the inner pipe and the outer pipe is arranged in the center of the fuel injection pipe, and the fuel and oxygen are ejected to the outer periphery of the powder flux ejection port. An apparatus for removing deposits on a molten metal container, characterized in that a hole is provided around it.