JP6898128B2 - Titanium tetrachloride manufacturing equipment and method for manufacturing titanium tetrachloride using this - Google Patents

Description

The present invention is an apparatus for producing titanium tetrachloride by using an ore containing titanium oxide as a raw material and supplying chlorine gas from below to form a fluid layer composed of ore and coke and reacting them. Titanium chloride production method, especially the bottom plate of titanium tetrachloride production equipment is less likely to be corroded, and the titanium tetrachloride production equipment that can operate for a longer time than the conventional titanium tetrachloride production equipment and titanium tetrachloride using this It is related to the manufacturing method of.

Titanium tetrachloride is a raw material especially for producing titanium sponge, and usually, a fluidized layer is formed from chlorine gas, ore containing titanium oxide, and coke in a titanium tetrachloride producing apparatus, and this is 1000. It is manufactured by chlorinating titanium oxide while maintaining a high temperature of about ° C.
Such a titanium tetrachloride manufacturing apparatus will be described with reference to the drawings. FIG. 1 is an outline of the titanium tetrachloride manufacturing apparatus A. The inner surface of the titanium tetrachloride manufacturing apparatus is made of refractory brick B. Chlorine gas is input from below the titanium tetrachloride production apparatus, and ore and coke containing titanium oxide are input from the raw material input port 3 on the side surface. Chlorine gas is dispersed and supplied from the dispersion board 1 arranged in the lower part of the chloride furnace, the fluidized bed 2 is formed in the upper part of the dispersion board 1, and the gaseous titanium tetrachloride reacted and generated in the fluidized bed 2 is produced. It is discharged from the discharge port 4 and collected.

The conventional dispersion board is composed of a dispersion layer in which inert particles such as silica and alumina having fire resistance and chlorine resistance are spread on the upper surface of a metal bottom plate such as iron provided with a large number of ventilation holes. there were. The chlorine gas supplied from below the dispersion board passes through the ventilation holes of the bottom plate, rises through the gaps between the inert particles, is uniformly dispersed, and is supplied to the fluidized bed.
However, when a conventional dispersion board is used, the bottom plate is corroded by chlorine gas during the continuation of operation, the ventilation holes are expanded and chlorine leaks due to holes on the bottom plate, and chlorine gas is evenly distributed in the fluidized chloride furnace. There was a problem that it could not be supplied to.

Therefore, two prior arts have been reported in order to prevent such corrosion of the bottom plate.
The dispersion board disclosed in Patent Document 1 forms a heat insulating layer made of an amorphous refractory between the bottom plate and the dispersion layer. By providing such a heat insulating layer, it is said that it is possible to prevent high-temperature titanium ore particles that have fallen from the fluidized bed from passing through the gaps between the dispersed layers and reaching the bottom plate.
However, with amorphous refractories, the temperature near the bottom plate cannot be controlled when the production volume increases, the temperature of the bottom plate rises, and chlorine reacts with the bottom plate, causing corrosion of the bottom plate.
Further, in the dispersion board disclosed in Patent Document 2, the dispersion layer formed on the bottom plate is composed of solid particles made of a high-purity ceramic material which is chlorine-resistant inert particles. As a result, it is said that corrosion and wear due to chlorine gas can be effectively suppressed. However, the temperature of the bottom plate rises when the high-temperature titanium ore particles falling from the fluidized bed pass through the gaps of the dispersion layer and reach the bottom plate, and it is not possible to prevent the bottom plate from reacting with chlorine and corroding. There was a problem. Furthermore, this technique does not achieve uniform dispersion of chlorine gas in the titanium tetrachloride production equipment if the particle size of the solid particles is too large, while if the particle size of the solid particles is too small, the chlorine gas is blown out. There is also a problem that solid particles are rolled up and scattered in the fluidized bed, the heat insulating effect on the bottom plate is weakened, and the bottom plate is corroded.

Japanese Unexamined Patent Publication No. 2014-210689 International release WO2005 / 080272

The present invention solves the problems of the prior art, prevents corrosion of the bottom plate of the titanium tetrachloride manufacturing apparatus, and can significantly extend the operating time as compared with the conventional titanium tetrachloride manufacturing apparatus. It is an object of the present invention to provide a manufacturing apparatus and a method for manufacturing titanium tetrachloride using the same.

The present invention adopts the following configuration in order to solve the problems of the prior art.
(1) A chloride reaction furnace in which chlorine gas is supplied from the lower part to form a fluidized bed, and a heat insulating layer having a thickness of 300 mm or more composed of heat-resistant and chlorine-resistant inert particles is arranged on the bottom plate and the upper surface of the bottom plate. A block layer in which heat-resistant and chlorine-resistant blocks are spread to a thickness of 100 mm or more is arranged on the upper part of the heat insulating layer, and a gas supply pipe capable of supplying chlorine from the bottom of the bottom plate to the top of the block layer is arranged. Titanium tetrachloride manufacturing equipment.
(2) The titanium tetrachloride manufacturing apparatus according to (1), wherein the density of the inert particles constituting the heat insulating layer is 2.0 to 4.0 g / cm ^3.
(3) The titanium tetrachloride manufacturing apparatus according to (1), wherein the density of the blocks constituting the block layer is 2.0 to 3.3 g / cm ^3.
(4) The titanium tetrachloride manufacturing apparatus according to (1), wherein the gas supply pipe is made of silicon nitride.
(5) A method for producing titanium tetrachloride using the titanium tetrachloride producing apparatus according to any one of (1) or (2).

In the present invention, by arranging a block layer in which heat-resistant and chlorine-resistant blocks are spread on the heat insulating layer made of inert particles, the heat insulating layer does not scatter into the fluidized bed and from the fluidized bed. Raw materials such as ore particles containing high-temperature titanium oxide that have fallen pass through the gaps in the heat insulating layer, do not partially corrode the bottom plate, and improve the heat insulating effect, thereby extending the life of the bottom plate. The operating time of the titanium tetrachloride manufacturing equipment can be significantly extended.

It shows the whole of the titanium tetrachloride production apparatus of this invention. It shows the dispersion board in the titanium tetrachloride production apparatus of this invention. It shows the relationship between the gas supply pipe, the heat insulating layer and the block layer in the dispersion board of this invention.

Hereinafter, the members constituting the titanium tetrachloride manufacturing apparatus of the present invention will be individually described.
The dispersion board is for dispersing and supplying chlorine gas in the titanium tetrachloride manufacturing apparatus, and is composed of a bottom plate, a heat insulating layer, a block layer, and a gas supply pipe.

The bottom plate of the titanium tetrachloride manufacturing apparatus of the present invention is used to support the weight of the raw material and the gas supply pipe in the heat insulating layer, the block layer, the fluidized bed in the titanium tetrachloride producing apparatus. Specifically, the material of the bottom plate may have chlorine resistance, and is preferably a steel material, a steel material with a ceramic lining, Hastelloy C, a nickel material, or the like, and Hastelloy C, a nickel material, or a steel material is particularly preferable. Among them, since the bottom plate is a consumable item, a steel material having a low price is more preferable.
The thickness of the bottom plate is preferably 20 mm or more, more preferably 20 to 100 mm, and even more preferably 30 to 70 mm. When the thickness of the bottom plate is 20 mm or more, the weight of the heat insulating layer and the block layer can be sufficiently supported, and the risk of chlorine gas leaking due to holes in the bottom plate due to wear due to corrosion etc. is reduced. It is preferable in terms of extending the life of the titanium chloride production apparatus. The upper limit of the thickness of the bottom plate is set in terms of cost for the effect.
Further, since the bottom plate 6 needs to blow chlorine into the titanium tetrachloride manufacturing apparatus through the gas supply pipe 9 described later, the bottom plate 6 is a window that is a cavity for supplying chlorine gas in the lower part of the bottom plate 6. Since chlorine is supplied from the box 5 into the fluidized bed 2, it has a plurality of through holes (omitted in the drawings) (FIGS. 1 and 2).

The heat insulating layer of the titanium tetrachloride manufacturing apparatus of the present invention is a layer arranged on the upper surface of the bottom plate and is composed of a layer of heat-resistant and chlorine-resistant inert particles. The inert particles used are composed of particles having a particle diameter of 10 to 100 mm and a stone-like (atypical), dice-like, or spherical shape. By using the inert particles having such a shape, voids are formed between the inert particles, and the voids exhibit the effect of heat insulation.
The range of the particle size of the present invention shall pass through a sieve having a predetermined value and not pass through a sieve having a predetermined value. For example, when the particle size is 10 mm to 100 mm, it passes through a sieve having a mesh size of 100 mm and does not pass through a sieve having a particle size of 10 mm.

The density of the inert particles used in the heat-insulating layer is preferably 2.0~4.0g / cm ^3, more preferably 2.0~2.6g / cm ^3, is 2.2~2.6g / cm ³ More preferred. By setting the density of the inert particles within this range, both heat insulation and strength can be ensured.
As the material of the heat-resistant and chlorine-resistant inert particles, silica, mullite, and silicon nitride are preferable, and silica and silicon nitride are particularly preferable. Among silica, silica stone and molten silica are preferable, and among silicon nitride, low-density silicon nitride is preferable. Further, the inert particles constituting the heat insulating layer may be a mixture of particles of these materials.
For example, low-density silicon nitride is an inert particle having a density of about 2.0 g / cm ³ , and Al ₂ O ₃ (density 3.9 g / cm) ^{is an inert particle having a density of about 4.0 g / cm 3.} There is ^3).
By arranging the heat insulating layer on the upper part of the bottom plate, it is possible to prevent the bottom plate from becoming hot and extend the life of the bottom plate. Further, the heat insulating layer having many voids also has an effect of alleviating the impact applied to the gas supply pipe when the blowout pipe and the raw material in the fluidized bed come into contact with each other, and damage to the gas supply pipe can be reduced.
Further, the heat insulating layer may be a plurality of layers in which layers of inert particles of different materials are laminated. For example, a heat insulating layer filled with silica stone or molten silica having a density of 2.2 to 2.6 g / cm ³ and a particle size of 10 to 30 mm so as to have a height of 300 to 400 mm is arranged, and the density 2. 0~2.4g / cm ^3, it is possible to arrange the heat-insulating layer filled so that the height 100~200mm low density silicon nitride particle size 20 to 100 mm.

The block layer of the titanium tetrachloride manufacturing apparatus of the present invention is a layer arranged above the heat insulating layer and is composed of blocks having a low porosity. If the shape of the block is plate-shaped, rod-shaped, or rectangular parallelepiped, the effect of the present invention is likely to be exhibited. If the block is rectangular parallelepiped, the vertical and horizontal dimensions are about 100 mm, and the thickness is more preferably about several tens of mm. ..
As the material of the block, chlorine-resistant non-oxide ceramics, oxide ceramics and the like are preferably used. Among the non-oxide ceramics, low-density silicon nitride (density 2.0 to 3.1 g / cm ³ ), high-density silicon nitride (density 3.1-3.3 g / cm ³ ), and silicon carbide are preferable. Further, as the oxide-based ceramic, alumina, silica, mullite, and fire-resistant clay are preferable. Such blocks include refractory bricks, especially chamotte bricks and mullite bricks. Among these, the block material is preferably high-density silicon nitride.
Density of the blocks constituting the block layer of the present invention is preferably 2.0~3.3g / cm ^3, more preferably 2.6~3.3g / cm ^3, more preferably 3.1~3.3g it is preferably / cm ^3. By setting the block density to 2.0 to 3.3 g / cm ³ , even if a raw material such as ore particles containing titanium oxide in the fluidized bed collides with a gas supply pipe described later, it is less likely to break, and the gas supply pipe Life is extended.
By laying the blocks densely in the gaps between the gas supply pipes above the heat insulating layer, the raw materials in the fluidized bed are less likely to break even if they collide with the gas supply pipes, and the life of the gas supply pipes is extended. In addition, particles of the heat insulating layer are less likely to be scattered in the fluidized bed, and the heat insulating effect on the bottom plate becomes longer. Further, since the block layer has few voids, it is possible to prevent the high-temperature raw material from falling to the bottom plate and heating the bottom plate, and the high-temperature bottom plate from reacting with chlorine to be damaged. The presence of such a block layer can significantly extend the operating time of the titanium tetrachloride manufacturing apparatus.

As an example of the block used in the block layer, when a low-density silicon nitride block (dimensions: 80 mm to 150 mm × 50 to 100 mm × 30 to 80 mm) is used, the density is 2.0 to 3.1 g / cm ³ , and heat is applied. Those having a conductivity of about 3 W / m · K (350 ° C.) are suitable.
When a high-density silicon nitride block (dimensions: 50 to 200 mm × 50 to 200 mm × 10 to 50 mm) is used, the density is 3.1 to 3.3 g / cm ³ (porosity 0%) and the thermal conductivity. Those at 25 W / m · K (350 ° C.) are suitable.
The larger the block size, the more preferable it is because it does not get caught in the fluidized bed.
Further, the block layer may be formed by arranging blocks in the order of low-density silicon nitride and high-density silicon nitride on the heat insulating layer.
The density of the inert particles used for the heat insulating layer of the present invention or the blocks constituting the block layer is the apparent density. The apparent density of the present invention can be measured by the Archimedes method. Specifically, the sample for which the apparent density is to be measured is submerged in water in a container, the sample volume is measured from the change in the liquid level before and after the sample is charged, and the sample weight and the sample volume are calculated.

The gas supply pipe of the titanium tetrachloride manufacturing apparatus of the present invention is a pipe that supplies chlorine gas from below the bottom plate to above the block layer. The material of the gas supply pipe is preferably one having high heat resistance and chlorine resistance because it comes into contact with chlorine at a high temperature. As such a material, mulite, fused silica, low-density silicon nitride, high-density silicon nitride and the like are preferable, low-density silicon nitride and high-density silicon nitride are more preferable, and high-density silicon nitride is further preferable.
Since chlorine gas needs to be blown out from above the block layer, it is preferable that the chlorine gas outlet of the gas supply pipe is higher than the block layer. The height from the upper end of the gas supply pipe to the block layer is preferably 100 mm or less. By setting the height of the gas supply pipe within this range, it is possible to reduce damage to the gas supply pipe due to an impact such as a collision with a raw material in the fluidized bed.

The shape of the gas supply pipe may be any shape as long as it has a hollow structure capable of blowing out gas. In order to prevent the raw materials and the like in the fluidized bed from flowing back, it is preferable that the portion of the gas supply pipe that blows out the gas has a structure in which the tip portion is closed and the gas can be blown out from the lateral direction. The gas supply pipe may be connected to the upper part of the bottom plate 6. In order to uniformly disperse and supply chlorine gas, a plurality of supply ports of the gas supply pipe may be vacant on the bottom plate.
The amount of chlorine gas blown out is preferably ^{200 to 600 Nm 3} / h · m ^{2 per dispersion board cross-sectional area.}
When the blowing speed of chlorine gas is 200 Nm ³ / h · m ² or more, the formation of an appropriate fluidized bed is ensured, and when it is 600 Nm ³ / h · m ² or less, high productivity can be maintained.

An embodiment of the method for producing titanium tetrachloride will be described with reference to FIGS. 1 to 3 of the titanium tetrachloride producing apparatus of the present invention. Ore and coke containing titanium oxide are charged from the raw material supply port 3 of the titanium tetrachloride manufacturing apparatus, and chlorine gas is supplied from the gas supply pipe 9 arranged on the bottom plate 6 of the fluidized bed 1 under high temperature (inside the furnace). The fluidized bed 2 is formed in the lower part of the titanium tetrachloride manufacturing apparatus at a temperature of 900 ° C. to 1100 ° C.). As a result, the ore containing titanium oxide is chlorided by the gas, and gaseous titanium tetrachloride is generated and discharged from the discharge pipe 4 (for example, resources and materials 109 P1158 (1993) "Toho Titanium Co., Ltd. sponge". See 2.1 Liquid Making Process in "Manufacturing Titanium and Ingots").

Hereinafter, the contents of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these examples.
As the titanium tetrachloride manufacturing apparatus, the titanium tetrachloride producing apparatus having the shape shown in FIGS. 1 to 3 was used.
The bottom plate 6 used had a thickness of 50 mm and a material of carbon steel (SS400).
The heat insulating layer 7 is made of silicon (density: 2.4 g / cm ³ , composition: SiO ₂ , other Al ₂ O ₃ , Fe ₂ O _3, etc.), molten silica (density 2.6 g / cm ³ , purity 99. 8%, composition SiO ₂ , other Al ₂ O ₃ , Fe ₂ O _3, etc., pore ratio 0.1% or less), low density silicon nitride (density: 2.2 g / cm ³ , composition: Si ₃ N _{4 and} other small amounts Al ₂ O ₃ , Fe ₂ O _3, etc., Pore ratio: 27%), high-density silicon nitride (density 3.3 g / cm ³ , composition: Si ₃ N _{4 and} other binders (eg Al ₂ O _3, etc.) , Inactive particles selected from (pore ratio 0%) were filled and formed so that the thickness of the layer changed for each example.
The block layer 8 is made of a block (100 mm × 100 mm × 30 mm) made of high-density silicon nitride (density: 3.3 g / cm ³ , composition: Si ₃ N _{4 and} other binders (eg Al ₂ O _3)). , The layers were laid out so that the thickness of the layers changed for each example, and were formed by stacking as necessary.
Regarding the life of the titanium tetrachloride manufacturing apparatus, the operation was stopped because it was judged that the life of the dispersion board was when the temperature of the bottom plate reached 120 ° C. This is because iron and chlorine react when the bottom plate reaches a high temperature of 120 ° C. or higher.

[Example 1]
In addition to the above conditions, the heat insulating layer 7 was filled with silica stone inert particles so as to have a thickness of 500 mm. Further, high-density silicon nitride was used for the block layer 8 so that the thickness was 100 mm, and the test was conducted. The chlorine gas supply rate was set to 500 Nm ³ / h · m ² . The results are shown in Table 1.
[Example 2]
The test was conducted under the same conditions as in Example 1 except that the thickness of the heat insulating layer 7 was changed from 500 mm to 400 mm. The results are shown in Table 1.
[Example 3]
The test was conducted under the same conditions as in Example 1 except that the thickness of the block layer 8 was changed from 100 mm to 200 mm. The results are shown in Table 1.
[Example 4]
As the heat insulating layer 7, it was carried out except that a layer made of silica stone having an average particle size of 15 mm (thickness 400 mm) was formed on the bottom plate and a layer made of low-density silicon nitride having an average particle size of 30 mm (thickness 100 mm) was formed above the layer. The test was conducted under the same conditions as in Example 1. The results are shown in Table 1.
[Comparative Example 1]
The block layer 8 is not used, and the heat insulating layer 7 is a layer made of silica stone having an average particle size of 15 mm (thickness 250 mm), and a layer made of molten silica having an average particle size of 30 mm (thickness 250 mm). The test was carried out under the same conditions as in Example 1 except that the one described in 2) was used. The results are shown in Table 1.
[Comparative Example 2]
The test was conducted under the same conditions as in Example 1 except that an amorphous refractory having a thickness of 600 mm (described in Patent Document 1) was used instead of the heat insulating layer 7 and the block layer 8. The results are shown in Table 1.
[Comparative Example 3]
The test was conducted under the same conditions as in Example 1 except that the thickness of the heat insulating layer 7 was changed from 500 mm to 250 mm. The results are shown in Table 1.
[Comparative Example 4]
The test was conducted under the same conditions as in Example 1 except that the thickness of the block layer 8 was changed from 100 mm to 50 mm. The results are shown in Table 1.

As is clear from Table 1, the sufficient effect cannot be exhibited unless the thickness of both the heat insulating layer and the block layer is more than a certain level. That is, in Comparative Examples 1, 2 and 4, the heat insulating layer has a sufficient thickness, but the thickness of the block layer is not sufficient, so that the life is short. In Comparative Example 3, the thickness of the block layer is short. Even if the amount is sufficient, the result is not favorable because the thickness of the heat insulating layer is thin.
From the results shown in this table, it can be seen that the heat insulating layer must be 300 mm or more and the block layer must be 100 mm or more in order to achieve the intended purpose.

Claims (5)

A chloride reactor that supplies chlorine gas from the bottom to form a fluidized bed.
A block having a bottom plate and a heat insulating layer having a thickness of 300 mm or more composed of heat-resistant and chlorine-resistant inert particles is arranged on the upper surface of the bottom plate, and heat-resistant and chlorine-resistant blocks are spread over the heat insulating layer to a thickness of 100 mm or more. A titanium tetrachloride manufacturing apparatus characterized in that a layer is arranged and a gas supply pipe capable of supplying chlorine from the bottom of the bottom plate to the top of the block layer is arranged.
Platelike block, rod-like block, and a rectangular parallelepiped wherein the blocking layer comprises one or more blocks is constructed, and the gas supply pipe to that of titanium tetrachloride production apparatus characterized in that it consists of silicon nitride. A chloride reactor that supplies chlorine gas from the bottom to form a fluidized bed.
A block having a bottom plate and a heat insulating layer having a thickness of 300 mm or more composed of heat-resistant and chlorine-resistant inert particles is arranged on the upper surface of the bottom plate, and heat-resistant and chlorine-resistant blocks are spread over the heat insulating layer to a thickness of 100 mm or more. A titanium tetrachloride manufacturing apparatus characterized in that a layer is arranged and a gas supply pipe capable of supplying chlorine from the bottom of the bottom plate to the top of the block layer is arranged.
A titanium tetrachloride manufacturing apparatus, wherein the gas supply pipe is made of silicon nitride. The titanium tetrachloride production apparatus according to claim 1 or 2 , wherein the density of the inert particles constituting the heat insulating layer is 2.0 to 4.0 g / cm ^3. The titanium tetrachloride manufacturing apparatus according to claim 1 or 2 , wherein the density of blocks constituting the block layer is 2.0 to 3.3 g / cm ^3. A method for producing titanium tetrachloride, which comprises producing titanium tetrachloride using the titanium tetrachloride producing apparatus according to claim 1 or 2.

Images