Reduction reaction container

Abstract

To provide a reduction reaction container which can be easily provided with an opening for removing metal titanium while maintaining heat resistance.SOLUTION: A reduction reaction container 1 comprises: a cylindrical reduction reaction container body having a bottom wall 10b; a cylindrical projecting part 11 projecting downwards from the bottom wall of the reduction reaction container body and having an opening part 11c opening downwards in a lower end; and a bottom plate 12 joined to the projecting part so as to clog the opening part and having a hardness lower than the hardness of the reduction reaction container body. The projecting part includes: an upper projecting part 11a on the side of the reduction reaction container body; and a lower projecting part 11b joined with the bottom plate and having a hardness lower than the hardness of the reduction reaction container body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a reduction reaction vessel.

Background Art

[0002] Patent Document 1 discloses a cylindrical reduction reaction vessel for reducing titanium halide when producing metallic titanium.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the reduction reaction vessel described in Patent Document 1, metallic titanium generated by the reduction reaction accumulates on a tray (lost and found) installed on the bottom wall. The reduction reaction vessel is provided with a cylindrical convex portion protruding downward on the bottom wall of the reduction reaction vessel. The lower end of the convex portion is open downward, and a bottom plate for closing the opening is joined to the lower end of the convex portion by welding. When removing the generated metallic titanium from the reduction reaction vessel, the welded portion between the bottom plate and the convex portion is removed by cutting or the like, and a cylinder of a cylinder pushes the tray upward through the opening at the lower end of the convex portion, whereby the metallic titanium is taken out from the upper end of the reduction reaction vessel.

[0005] On the other hand, when reducing titanium halide, since the temperature inside the reduction reaction vessel rises to about 1000 ° C, a high heat-resistant stainless steel or the like is used for the reduction reaction vessel. Since stainless steel has a higher hardness and poorer machinability than other metals such as carbon steel, the above cutting process is difficult.

[0006] An object is to provide a reduction reaction vessel that can easily remove the bottom plate in order to take out metallic titanium while maintaining heat resistance.

Means for Solving the Problem

[0007] As described above, since the reduction reaction vessel is used at a high temperature of about 1000°C, it has been considered difficult to use a material such as carbon steel, which has a lower hardness than stainless steel and excellent machinability, for the reduction reaction vessel. However, the inventor of the present application found through experiments that even when the bottom plate is changed to carbon steel, which has a lower hardness than stainless steel and excellent cuttability, the reduction reaction vessel can be used without problems, and thus conceived the present invention.

[0008] The present disclosure a cylindrical reduction reaction vessel body having a bottom wall; a cylindrical convex portion protruding downward from the bottom wall of the reduction reaction vessel body and having an opening that opens downward at the lower end; a bottom plate joined to the convex portion so as to close the opening and having a hardness lower than that of the reduction reaction vessel body and provides a reduction reaction vessel.

[0009] According to the reduction reaction vessel according to the present disclosure, a bottom plate having a hardness lower than that of the reduction reaction vessel body is joined to the lower end of the convex portion. Thereby, while maintaining the heat resistance of the reduction reaction vessel body, which is easily affected by heat, the machinability of the joint portion between the convex portion and the bottom plate is improved, and the bottom plate can be easily removed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In addition, the sizes and shapes of the respective components shown are schematically shown and are different from the actual ones.

[0012] Figure 1 shows a longitudinal sectional view of the reduction reaction vessel 1 according to the present embodiment extending in the vertical direction. In this specification, the vertical direction of the reduction reaction vessel 1 is defined as the up-down direction.

[0013] The reduction reaction vessel 1 is a reaction vessel for subjecting titanium halide, which is a precursor, to a reduction reaction when manufacturing metallic titanium. By subjecting titanium halide to a reduction reaction in the reduction reaction vessel 1, metallic titanium is produced. A detailed method for manufacturing metallic titanium is described, for example, in Japanese Patent Laid-Open No. 6-81051.

[0014] The reduction reaction vessel 1 includes a reduction reaction vessel main body 10 having a cylindrical portion 10a and a bottom wall 10b, and a cylindrical convex portion 11 protruding downward from the bottom wall 10b. Inside the reduction reaction vessel main body 10, a reduction reaction of titanium halide is carried out to produce metallic titanium. The upper end of the reduction reaction vessel main body 10 is open and is closed by a lid body 13 during the reduction reaction. The bottom wall 10b of the reduction reaction vessel main body 10 has a curved shape protruding downward.

[0015] Figure 2 shows the process of taking out metallic titanium after the reduction reaction has ended in the reduction reaction vessel 1 and metallic titanium has been produced. In the reduction reaction vessel 1, a tray 2 having a shape along the bottom wall 10b of the reduction reaction vessel main body 10 is provided on the bottom wall 10b. On the tray 2, metallic titanium 3 produced by the reduction reaction is deposited. Also, since the reduction reaction has ended, the lid body 13 has been removed.

[0016] With reference to FIG. 1, the detailed structure of the reduction reaction vessel 1 will be described. The convex portion 11 is arranged such that the center in its radial direction coincides with the center in the radial direction of the reduction reaction vessel main body 10. The convex portion 11 has a cylindrical upper convex portion 11a on the side of the reduction reaction vessel main body 10 and a cylindrical lower convex portion 11b on the side opposite to the reduction reaction vessel main body 10. The inner diameter and outer diameter of the upper convex portion 11a and the lower convex portion 11b are the same and are continuous in the vertical direction. The upper convex portion 11a is formed integrally with the reduction reaction vessel main body 10. The lower convex portion 11b is joined to the upper convex portion 11a by covered arc welding in a state where the upper end surface of the lower convex portion 11b and the lower end surface of the upper convex portion 11a are butted against each other. The welding is performed over the entire circumference of the lower convex portion 11b and the upper convex portion 11a. In this welding, an alumite-based welding rod, for example, the product name "B-17" manufactured by Kobe Steel, Ltd. is used.

[0017] The inner diameter D2 and height H2 of the convex portion 11 are smaller than the inner diameter D1 and height H1 of the reduction reaction vessel main body 10. The ratio (D2 / D1) of the inner diameter D2 of the convex portion 11 to the inner diameter D1 of the reduction reaction vessel main body 10 is set in the range of 20% to 40%. The ratio (H2 / H1) of the height H2 of the convex portion 11 to the height H1 of the reduction reaction vessel main body 10 (the distance from the upper end of the reduction reaction vessel main body 10 to the boundary with the convex portion 11 (the dotted line in FIG. 1)) is set in the range of 1% to 10%.

[0018] The ratio (H3 / H2) of the height H3 of the lower convex portion 11b to the height H2 of the convex portion 11 is set in a range higher than 5% and 90% or less, preferably in a range higher than 15% and 80% or less.

[0019] The lower end of the lower convex portion 11b is open downward. The reduction reaction vessel 1 further includes a bottom plate 12 that closes the opening (hereinafter referred to as the opening portion 11c) from below at the lower end of the lower convex portion 11b. The bottom plate 12 is a disc having substantially the same outer diameter as the convex portion 11. The bottom plate 12 is joined to the lower convex portion 11b by covered arc welding with the upper surface of the bottom plate 12 and the lower end surface of the lower convex portion 11b abutted against each other. The welding is performed over the entire circumference of the lower convex portion 11b and the bottom plate 12. In this welding, an alumite-based welding rod, for example, the product name "B-17" manufactured by Kobe Steel, Ltd., is used.

[0020] To maintain the airtightness inside the reduction reaction vessel 1, welding is preferable for the joining of the reduction reaction vessel body 10 and the upper convex portion 11a, and for the joining of the upper convex portion 11a and the bottom plate 12. Also, other airtight connection means, for example, bolt fastening means using a gasket, are not preferable because the gasket may be melted by the high-temperature melt during the reduction reaction and the melt may leak from the reduction reaction vessel.

[0021] The materials of the reduction reaction vessel body 10 and the upper convex portion 11a are stainless steel, specifically, heat-resistant steels such as SUS304, SUS304L, SUS305B, SUS310, and SUS316. Since the temperature inside the reduction reaction vessel body 10 during the reduction reaction rises to about 1000°C, stainless steel with excellent heat resistance is used. The hardness of these materials is generally 187 HB.

[0022] The materials of the lower convex portion 11b and the bottom plate 12 are carbon steel, specifically, SS400, SB410, SM400, etc. These materials are inferior in heat resistance compared to stainless steel, but have excellent machinability because they have lower hardness than stainless steel. The hardness of the carbon steel used for the lower convex portion 11b and the bottom plate 12 in this embodiment is generally 100 - 150 HB. Therefore, the hardness of the lower convex portion 11b and the bottom plate 12 is lower than the hardness of the reduction reaction vessel body 10 and the upper convex portion 11a.

[0023] Next, the process of taking out metallic titanium from the reduction reaction vessel 1 according to this embodiment will be described with reference to FIG. 2.

[0024] The bottom plate 12 has been removed by cutting the joint with the lower convex portion 11b using a lathe or the like. The joint is mainly composed of a welding bead, and the welding bead includes the base materials of the bottom plate 12 and the lower convex portion 11b melted by the heat during welding. Also, during cutting, depending on the skill of the operator, a part of the bottom plate 12 and / or the lower convex portion 11b may be cut. Since a carbon steel with excellent machinability is used for the materials of the bottom plate 12 and the lower convex portion 11b in this embodiment, the removal of the bottom plate 12 can be easily performed.

[0025] When the materials of the bottom plate and the lower convex portion are the same stainless steel as the reduction reaction vessel body, in the removal of the bottom plate, more cutting time is required compared to this embodiment, and the cutting tool is more likely to wear, so frequent replacement of the cutting tool is necessary.

[0026] After the bottom plate 12 is removed, the cylindrical cylinder 4 pushes up the tray 2 from below through the opening 11c (see direction A in Fig. 2). As a result, the metallic titanium 3 rises together with the tray 2 and is taken out from the upper end of the reduction reaction vessel body 10.

[0027] In order to perform the reduction reaction of titanium halide in the same reduction reaction vessel 1 after the removal process is completed, the removed bottom plate 12 is welded again to the lower convex portion 11b by covered arc welding. When the removal and welding joint of the bottom plate 12 are repeated in this way, the lower convex portion 11b is cut during the cutting of the joint, and the height H3 gradually becomes shorter. In this embodiment, since H3 / H2 is set higher than 5%, preferably higher than 15%, the repeated removal and welding joint of the bottom plate 12 makes the lower convex portion disappear, and it is difficult for a situation to occur where the upper convex portion with poor machinability is cut.

[0028] Further, by setting H3 / H2 in the range of 90% or less, preferably 80% or less, the lower convex portion 11b can be kept as far as possible downward from the reduction reaction vessel main body 10. As a result, the influence of the heat generated by the reduction reaction on the lower convex portion 11b can be suppressed as much as possible. For this reason, carbon steel such as SS400 can be used for the lower convex portion 11b and the bottom plate 12 joined to the lower end of the lower convex portion 11b.

[0029] According to the reduction reaction vessel 1 according to the present embodiment, the following effects can be obtained.

[0030] (1) A cylindrical reduction reaction vessel main body 10 having a bottom wall 10b, A cylindrical convex portion 11 protruding downward from the bottom wall 10b of the reduction reaction vessel main body 10 and having an opening 11c opening downward at the lower end, A bottom plate 12 joined to the convex portion 11 so as to close the opening 11c and having a hardness lower than that of the reduction reaction vessel main body 10 are provided.

[0031] As a result, since the hardness of the bottom plate 12 is lower than that of the reduction reaction vessel main body 10, when removing the bottom plate 12 for taking out metallic titanium while maintaining the heat resistance of the reduction reaction vessel 1, cutting of the joint portion between the bottom plate 12 and the convex portion 11 can be easily performed.

[0032] (2) The convex portion 11 An upper convex portion 11a on the reduction reaction vessel main body 10 side, A lower convex portion 11b having a bottom plate 12 joined thereto at the lower end and having a hardness lower than that of the reduction reaction vessel main body 10 are provided. As a result, since the lower convex portion 11b to which the bottom plate 12 is joined has a hardness lower than that of the reduction reaction vessel main body 10, when removing the bottom plate 12 for taking out metallic titanium, cutting of the joint portion between the bottom plate 12 and the convex portion 11 can be performed more easily.

[0033] Note that the reduction reaction vessel 1 according to the present disclosure is not limited to the configuration of the above embodiment, and various modifications are possible.

[0034] The material of the lower convex portion 11b of the present embodiment is carbon steel, but it may be the same material as the reduction reaction vessel main body 10 and the upper convex portion 11a, that is, stainless steel. Even if the material of the lower convex portion is stainless steel, if the material of the bottom plate is carbon steel, the removal of the joint portion between the bottom plate and the lower convex portion can be easily performed as compared with the case where the material of the bottom plate is stainless steel.

[0035] The upper convex portion 11a of the present embodiment is formed integrally with the reduction reaction vessel main body 10, but it may be formed separately from the reduction reaction vessel main body.

[0036] The bottom plate 12 of the present embodiment is a disk having substantially the same outer diameter as the convex portion, but is not limited to this shape. The bottom plate may be a plate material that can block the opening of the convex portion from below. For example, the bottom plate may be a flat plate having an area larger than the outer circle of the convex portion. In this case, the bottom plate can be joined to the convex portion by fillet welding.

[0037] The lower convex portion and the bottom plate of the present embodiment are formed separately, but they may be formed integrally. In this case, at the time of the first extraction of metallic titanium, the side surface of the integral part of the lower convex portion and the bottom plate is cut by a lathe or the like, so that the bottom plate is separated from the lower convex portion and an opening is formed. After the metallic titanium is extracted by the cylinder, the separated bottom plate is joined to the lower convex portion by welding. The extraction of metallic titanium after the second time is the same as in the present embodiment.

Explanation of Signs

[0038] 1: Reduction reaction vessel 10: Reduction reaction vessel main body 10a: Cylindrical portion 10b: Bottom wall 11: Convex portion 11a: Upper convex portion 11b: Lower convex portion 11c: Opening 12: Bottom plate 13: Cover body 2: Tray 3: Metallic titanium 4: Cylinder A: Lifting direction

Claims

1. A cylindrical reduction reaction vessel body having a bottom wall, A cylindrical convex portion that protrudes downward from the bottom wall of the reduction reaction vessel body and has an opening that opens downward at the lower end, A bottom plate that is joined to the convex portion so as to close the opening and has a hardness lower than that of the reduction reaction vessel body A reduction reaction vessel comprising:

2. The convex portion An upper convex portion on the reduction reaction vessel body side, A lower convex portion having a hardness lower than that of the reduction reaction vessel body, to which the bottom plate is joined at the lower end having, The reduction reaction vessel according to claim 1.

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