JP2001073042A - Reducing vessel for producing sponge titanium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reducing vessel for producing titanium provided with an extracting tube for fused magnesium and/or fused magnesium chloride suitable for producing high purity sponge titanium. SOLUTION: A reducing vessel 10 for producing sponge titanium is provided with an extracting tube 20 for fused magnesium and/or fused magnesium chloride connected to the bottom part 12 of the vessel. The extracting tube 20 is composed of a double structure provided with an inner tube 22 and an outer tube 24 arranged on the outer side of the inner tube 22, and the inner tube 22 is composed of soft steel, and the outer tube 24 is composed of stainless steel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reducing container for producing titanium sponge, and more particularly, to a reducing container for producing titanium sponge having an improved pipe for extracting molten magnesium and / or molten magnesium chloride.

[0002]

2. Description of the Related Art Conventionally, in a method for producing titanium sponge by the Kroll method, titanium tetrachloride is dropped into a reduction vessel holding molten magnesium. Since the reduction container is required to have heat resistance and corrosion resistance, stainless steel is generally used.

However, there is a problem that nickel (Ni) and chromium (Cr) are eluted from the stainless steel in the molten magnesium held in the reduction vessel made of stainless steel. Nickel and chromium eluted from stainless steel in this way react with titanium tetrachloride dropped into molten magnesium and are taken up in purified titanium particles, resulting in a decrease in quality in the generated titanium sponge. There was an inconvenience. In particular, in the production of high-purity titanium sponge, this point cannot be ignored.

Therefore, in the production of titanium sponge of high purity, a technique is known in which the inner surface of the reduction vessel is usually lined with mild steel containing little impurities such as nickel and chromium. Also, at the beginning of the reaction, the molten magnesium is in contact with the pipe for extracting the molten magnesium chloride produced as a by-product of the reduction reaction. For this reason, the molten magnesium chloride extraction pipe is also made of mild steel containing few impurities.

[0005]

As described above, when the molten magnesium chloride extraction pipe is made of mild steel, the outer surface of the magnesium chloride extraction pipe made of mild steel is exposed to the atmosphere, so that oxidation consumption is reduced. There was a problem in terms of durability intensely.

An object of the present invention is to provide a reduction container for producing titanium, which is provided with a molten magnesium and / or molten magnesium chloride extraction tube suitable for producing high-purity titanium sponge. Another object of the present invention is to provide a reduction container for producing titanium, which is provided with a molten magnesium and / or molten magnesium chloride withdrawing tube which has little elution of impurities from the molten magnesium and / or molten magnesium chloride withdrawing tube and has low oxidation consumption. To provide. Still another object of the present invention is to provide a molten magnesium and / or molten magnesium chloride withdrawing tube which has little elution of impurities from the molten magnesium and / or molten magnesium chloride withdrawing tube, has excellent durability, and is relatively easy to construct. It is an object of the present invention to provide a reduction container for producing titanium provided with the same.

[0007]

According to the present invention, there is provided a reducing container for producing sponge titanium according to the present invention, comprising a discharge pipe for molten magnesium and / or molten magnesium chloride connected to the bottom of the container. The tube is
This problem is solved by having a double structure including an outer pipe disposed outside the inner pipe, wherein the inner pipe is made of mild steel and the outer pipe is made of stainless steel.

In this case, as described in claim 2, a space is formed between the inner tube and the outer tube of the extraction tube, and a through hole communicating with the space and the reduction container is provided. It is preferable to configure the following.

It is preferable that a space is formed between the inner tube and the outer tube of the extraction tube, and that the space be formed of an inert gas atmosphere.

Further, it is preferable that a space is formed between the inner tube and the outer tube of the extraction tube, and that the space be filled with a gas absorber.

Further, as described in claim 5, it is more preferable that a space is formed between the inner tube and the outer tube of the extraction tube, and that the space be depressurized and filled with a gas absorber. .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In a reducing container 10 for producing titanium sponge according to the present invention, a discharge pipe 20 for molten magnesium and / or molten magnesium chloride is connected to a container bottom 12. The extraction pipe 20 has a double structure of an outer pipe 24 disposed outside the inner pipe 22.
In this example, the inner tube 22 is made of mild steel, and the outer tube 24 is made of stainless steel. In this way, by making the extraction pipe 20 have a double structure, it is possible to prevent impurities such as nickel and chromium from mixing from stainless steel and to prevent the inner pipe 22 from being oxidized and consumed.

A space 26 is formed between the inner tube 22 and the outer tube 24 of the extraction tube 20, and a through hole 28 communicating with the space 26 and the reduction vessel 10 is provided.
By forming the through-holes 28 in this manner, it is possible to perform an action of suppressing a pressure rise in the space 26 due to a rise in the temperature of the extraction pipe 20.

The space 26 between the inner tube 22 and the outer tube 24 is set to an inert gas atmosphere. By setting the space 26 in an inert gas atmosphere, the space 26
It is also possible to prevent the oxidative consumption of the inner tube 22 that comes into contact with, and it is possible to provide equipment suitable for producing titanium with higher purity.

Also, the inner tube 22 and the outer tube 2 of the extraction tube 20
4 so that the space 26 between them is filled with a gas absorber. Further, the space 26 between the inner tube 22 and the outer tube 24 of the extraction tube 20 is depressurized and filled with a gas absorber. With this configuration,
The space 26 between the outer pipe 24 and the inner pipe 22 and the reduction vessel 10
Does not have a through hole 28 between the
The molten magnesium and / or molten magnesium chloride charged therein can be prevented from entering the space 26. For this reason, quality contamination of the titanium sponge generated in the reduction container 10 can be avoided.

[0016]

An embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below do not limit the present invention, and can be variously modified within the scope of the present invention.

FIGS. 1 to 5 show an embodiment according to the present invention. FIG. 1 is a schematic structural view including a partial cross section of a reduction container for producing titanium, and FIG. 2 is a diagram showing molten magnesium and / or molten magnesium chloride. FIG. 3A-A is an external view of the extraction pipe, FIG. 3 is an explanatory view including a partial cross section of the extraction pipe for molten magnesium and / or molten magnesium chloride, and FIG. 4 is a view showing the essential parts of the extraction pipe for molten magnesium and / or molten magnesium chloride. FIG. 5 is an enlarged view of a main part of a drawing pipe of molten magnesium and / or molten magnesium chloride showing another example.

As shown in FIGS. 1 and 3, a molten magnesium and / or molten magnesium chloride extraction pipe 20 is connected to the bottom 12 of the reduction container 10 for titanium production by a plurality of connection support members 30. The molten magnesium and / or molten magnesium chloride extraction tube 20 has a double structure including an inner tube 22 and an outer tube 24. An outer tube 24 is provided outside the inner tube 22. The inner tube 22 is made of mild steel, and the outer tube 24 is made of stainless steel.

The inner tube 22 of the present embodiment is made of mild steel {SS400 (a kind of carbon steel)}. This mild steel prevents the elution of nickel and chromium into molten magnesium and / or molten magnesium chloride. I have. The outer tube 24 of the extraction tube 20 of this example is made of stainless steel (SUS
Etc.). The outer tube 24 protects the inner tube 22 from oxidative consumption.

A space 26 is formed between the extraction tube 20 and the outer tube 24. In this example, as shown in FIG. 4, a through-hole 28 communicating with the space 26 and the reduction container 10 is provided at the bottom of the extraction pipe 20. The through-hole 28 serves to suppress the pressure increase in the space 26 due to the temperature rise of the extraction pipe 20. In addition, the space 26 of this example is filled with an inert gas. As the inert gas, an argon gas is preferable.

According to the reducing container 10 for producing sponge titanium as described above, a part of the molten magnesium and / or the molten magnesium chloride filled in the reducing container 10 passes through the through hole 28 to the space of the extraction pipe 20. Although the gas enters the space 26, it is pushed by the argon gas existing in the space 26, so that the pressure in the space 26 and the molten magnesium and / or
Alternatively, when the difference in the upper position (head) between the molten magnesium chloride and the molten magnesium and / or the molten magnesium chloride charged into the reduction vessel 10 is balanced, the intrusion of the molten magnesium into the space 26 stops.

The molten magnesium that has entered the space 26 comes into contact with the outer tube 24 (so-called protective tube) made of stainless steel. However, when the size of the through hole 28 is set to 5 to 20 mm, the molten magnesium flowing from the through hole 28 to the space between the double tubes convects into the reduction vessel 10. , And the contamination of nickel and chromium in the titanium sponge generated in the reduction container 10 can be prevented.

FIG. 5 shows an example in which no through-hole 28 is provided between the space 26 and the reduction vessel 10. In this example, an example in which the space 26 is in an inert atmosphere is shown. That is, when the through hole 28 is formed between the space 26 between the outer tube 24 and the inner tube 22 and the reduction container 10 as in the above-described embodiment, the molten magnesium and / or The migration of the molten magnesium chloride cannot be completely prevented. This is the outer tube 2
No. 4 (stainless steel protection tube), which means that it cannot be completely prevented from being contaminated with nickel or chromium by being eluted into molten magnesium and / or molten magnesium chloride.

Therefore, in the present embodiment, no through hole 28 is provided between the space 26 between the outer tube 24 and the inner tube 22 and the reduction vessel 10, and an inert gas is filled in the space 26. Or it is configured to be distributed.

When an inert gas is allowed to flow, a sealing material (not shown) is provided at the end contact portions of the outer tube 24 and the inner tube 22.
Is arranged. When the inert gas is allowed to flow, connecting pipes (not shown) are connected to the outer pipe 24 at two places,
It is configured to supply and discharge.

As described above, since the through-hole 28 is not provided between the space 26 between the outer pipe 24 and the inner pipe 22 and the reduction vessel 10, the molten magnesium charged in the reduction vessel 10 And / or it is possible to prevent molten magnesium chloride from entering the space 26. For this reason, quality contamination of the titanium sponge generated in the reduction container 10 can be avoided.

The atmosphere of the inert gas in the space 26 is not particularly limited as long as it can prevent the mild steel constituting the extraction tube 20 from being oxidized and consumed. For example, nitrogen gas or argon gas is preferable.

Since the atmosphere in the space 26 need only be filled with the inert gas as described above, the inert gas does not necessarily need to be constantly circulated, but may be kept stationary. In such a case, the space 2
It is preferable that the pressure be slightly increased in order to prevent the intrusion of the atmosphere into the air. The pressure in the space 26 is 0.01-0.
It is preferable to adjust to about 05 Kg / cm ² G.

In the above-described embodiment, an example is shown in which the space 26 is filled with an inert gas. However, the space 26 may be held in a vacuum. That is, in each of the above embodiments, an inert gas such as an argon gas
However, as long as the inner tube 22 (mild steel) constituting the extraction tube 20 is prevented from being oxidized and consumed when it comes into contact with the space 26, a vacuum atmosphere may be used.

Further, a gas absorber may be sealed in the space 26 between the inner tube 22 and the outer tube 24. As the gas absorber, titanium sponge or titanium chips can be used. That is, by enclosing a titanium material sufficient for absorbing the oxygen gas and the nitrogen gas in the space 26, the oxygen gas and the nitrogen gas do not exist in the space 26.

As described above, when the gas absorber is sealed in the space 26, when the extraction tube 20 is heated and heated, the oxygen gas and the nitrogen gas existing in the space 26
It is absorbed by titanium sponge and cutting chips enclosed in 6. When the gas absorber is sealed in the space 26, the inner pipe 2 made of mild steel exposed to the space 26 is formed.
2 is suppressed. Further, there is no fear of deformation or rupture of the extraction tube due to gas expansion at the time of temperature rise.

Since the space 26 shifts to a state where the pressure is reduced, the space 26 is always subjected to the stress by the atmospheric pressure, and the space 26 is subjected to the deformation. But,
By filling the space 26 as tightly as possible with the titanium material, it is possible to withstand the stress caused by the atmospheric pressure, which is effective in preventing the extraction tube 20 from being deformed.

In each of the above embodiments, stainless steel is used for the outer tube 24. However, when the heating and heating are not repeated so much, the surface of the extraction tube 20 is subjected to ceramic spraying. Then, this ceramic layer is
4 may be used.

[0034]

As described above, according to the present invention, the elution of impurities from the molten magnesium and / or molten magnesium chloride withdrawal tube is small, the oxidation consumption is small, the durability is excellent, and the construction is relatively easy. It is possible to provide a reduction container for producing titanium, which is provided with a molten magnesium and / or molten magnesium chloride extraction tube suitable for producing high-purity sponge titanium.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram including a partial cross section of a reduction container for titanium production.

FIG. 2 is an external view of a drawing pipe of molten magnesium and / or molten magnesium chloride as viewed from FIG. 3A-A.

FIG. 3 is an explanatory view including a partial cross section of an extraction pipe for molten magnesium and / or molten magnesium chloride.

FIG. 4 is an enlarged view of a main part of an extraction pipe for molten magnesium and / or molten magnesium chloride.

FIG. 5 is an enlarged view of a main part of a tube for extracting molten magnesium and / or molten magnesium chloride showing another example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Reduction container for titanium sponge production 12 Bottom part of container 20 Extraction tube 22 Inner tube 24 Outer tube 26 Space 28 Through-hole

Claims (5)

[Claims] 1. A reduction container for producing titanium sponge, comprising a drainage tube for molten magnesium and / or molten magnesium chloride connected to a bottom of the container, wherein the drainage tube is disposed outside an inner tube. A reduction container for titanium sponge production, comprising a double structure having an outer tube, wherein the inner tube is made of mild steel and the outer tube is made of stainless steel. 2. The method according to claim 1, wherein a space is formed between the inner tube and the outer tube of the extraction tube, and a through-hole communicating with the space and the reduction vessel is provided. Reduction container for titanium sponge production. 3. The reduction container for producing titanium sponge according to claim 1, wherein a space is formed between the inner tube and the outer tube of the extraction tube, and the space is formed in an inert gas atmosphere. . 4. The sponge titanium according to claim 1, wherein a space is formed between the inner tube and the outer tube of the extraction tube, and the space is filled with a gas absorber. Reduction container for production. 5. A space is formed between an inner tube and an outer tube of the extraction tube, and the space is decompressed and filled with a gas absorber. 4. The reduction container for producing sponge titanium according to any one of 4.