JP5444745B2 - Trichlorosilane production equipment - Google Patents

Description

  The present invention relates to a trichlorosilane production apparatus for producing trichlorosilane by reacting metal silicon powder with hydrogen chloride gas.

Trichlorosilane (SiHCl ₃ ) used as a raw material for producing high-purity silicon is produced, for example, by reacting metal silicon powder (Si) with a purity of about 98% and hydrogen chloride gas (HCl). The
In order to produce trichlorosilane by reacting metal silicon powder with hydrogen chloride gas, a reaction apparatus for injecting hydrogen chloride gas into the reaction furnace from the bottom is proposed in a reactor to which metal silicon powder is supplied. Yes. In such an apparatus, a metal silicon powder having a particle size of, for example, 1000 μm or less is charged into a reaction furnace, hydrogen chloride gas is jetted into the reaction furnace from the bottom, and the metal silicon powder is caused to flow by the hydrogen chloride gas. However, the metal silicon powder and hydrogen chloride gas are sufficiently brought into contact with each other, and trichlorosilane can be obtained by these reactions.

In this apparatus, in order to further promote the reaction between the metal silicon powder and the hydrogen chloride gas, it is effective to uniformly diffuse the hydrogen chloride gas inside the reaction furnace without drifting. For this reason, conventionally, a porous nozzle or the like provided with a plurality of jet outlets has been used as a jet member that easily diffuses hydrogen chloride gas.
However, when a porous nozzle or the like is used, the jet port may be clogged with metal silicon powder, or the porous nozzle port may be enlarged due to wear. In this case, there is a problem that the metal silicon powder and hydrogen chloride gas cannot be uniformly contacted, the reaction in the furnace becomes non-uniform, and the production efficiency of trichlorosilane is reduced. Furthermore, there is a possibility that the reaction proceeds locally and the temperature of the part rises and the reaction apparatus itself is damaged. In addition, there is a problem that metal silicon powder collides with the drift of hydrogen chloride gas, and wear occurs on the inner surface of the reaction furnace, the thermometer, and the like.

  In Patent Document 1, in order to prevent clogging of the jet nozzle, a flat plate-shaped perforated small piece layer is provided on the upper side of the nozzle, and a small spherical object layer is further provided on the flat plate-shaped perforated small piece layer. Is disclosed. By providing the flat perforated small piece layer in this way, the metal silicon powder is prevented from entering the nozzle outlet, the nozzle is prevented from being clogged, and the nozzle is worn by the metal silicon powder. It is possible to prevent non-uniform ejection of hydrogen chloride gas due to the increase. In addition, since hydrogen chloride gas is jetted toward the metal silicon powder through the flat plate-shaped perforated small piece layer, it is possible to diffuse hydrogen chloride gas uniformly and widely and flow without uneven flow. Become.

Japanese Patent No. 2519094

  In the reactor for producing trichlorosilane described in Patent Document 1, a flat perforated small piece layer in which flat perforated small pieces are deposited, and a small spherical shape in which a ball material is deposited on the flat perforated small piece layer. Since the material layers are separated from each other, in the flat plate-like perforated piece layer, the flat plate-like perforated pieces are stacked in a lying state, and the flat plate-like perforated pieces are arranged so that they are in close contact with each other. May be. In the case where these perforated pieces are in close contact with each other, there is a fear that a void cannot be secured between the flat perforated pieces and the diffusion effect of hydrogen chloride gas cannot be fully achieved.

  On the other hand, since the demand for high-purity silicon is greatly increased, it is required to produce trichlorosilane more efficiently than before.

  This invention is made in view of such a situation, Comprising: It aims at providing the trichlorosilane manufacturing apparatus which can diffuse hydrogen chloride gas reliably and can improve the production efficiency of a trichlorosilane. And

The trichlorosilane production apparatus of the present invention is a trichlorosilane production apparatus in which metal silicon powder supplied into a reaction furnace is reacted while flowing with hydrogen chloride gas, and trichlorosilane produced by this reaction is taken out from the reaction furnace. The reactor includes a body part to which the metal silicon powder is supplied, a bottom part continuously provided at a lower part of the body part to which the hydrogen chloride gas is supplied, and a body part and a bottom part. A partition wall, and a nozzle attached to the partition wall, the nozzle having a jet port for ejecting the hydrogen chloride gas supplied to the bottom portion to the body portion, on the partition wall, from the upper surface of the partition wall a plurality of ball-shaped gas diffusion material having a different radius and height, and a plurality of plate-shaped gas diffusion member having a through hole is mixed so as to cover the periphery of the nozzle It is packed trees.

  According to the present invention, since the height of the ejection port for ejecting the hydrogen chloride gas is different from the radius of the ball-shaped gas diffusion material, the ejection port is not blocked by the ball-shaped gas diffusion material, Are ejected toward the lower or upper hemisphere of the gas diffusion material. Since the hydrogen chloride gas flows so as to diffuse along the lower hemisphere or the upper hemisphere of the ball-shaped gas diffusing material, the hydrogen chloride gas is diffused evenly and supplied to the body portion.

In this case, by a ball-like gas diffusion member and the plate-like gas diffusion material is mixed, so the gap between these gas diffusion material with each other is reliably formed, by diffusing more effectively hydrogen chloride gas Can do.

  According to the trichlorosilane manufacturing apparatus of the present invention, hydrogen chloride gas can be reliably diffused by the ball-shaped gas diffusing material, so that the production efficiency of trichlorosilane can be improved.

It is a longitudinal cross-sectional view which shows one Embodiment of the trichlorosilane manufacturing apparatus of this invention. It is a principal part enlarged view which shows the nozzle in the apparatus shown in FIG. It is a principal part enlarged view which shows the nozzle and gas diffusion material in the apparatus shown in FIG. It is a principal part enlarged view which shows the nozzle and gas diffusion material in the trichlorosilane manufacturing apparatus which concerns on other embodiment of this invention. It is a principal part enlarged view which shows the nozzle and gas diffusion material in the trichlorosilane manufacturing apparatus which concerns on other embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The trichlorosilane production apparatus 100 includes a reaction furnace 10, a raw material supply means 20 that supplies the reaction furnace 10 with metal silicon powder P as a raw material, and a gas introduction means that introduces hydrogen chloride gas to be reacted with the metal silicon powder P. 30 and a gas extraction means 40 for discharging the generated trichlorosilane gas.

The reaction furnace 10 has a trunk portion 11 that extends in the vertical direction, most of which is a straight cylinder, a bottom portion 12 that is coupled to the lower end of the trunk portion 11, and a large-diameter portion 13 that is coupled to the upper end of the trunk portion 11. And.
The body portion 11 and the bottom portion 12 are formed to have substantially the same diameter, and the space between them is partitioned by a horizontal partition 14. On the other hand, a tapered portion 15 having a diameter increasing upward is formed on the upper portion of the body portion 11. The large diameter portion 13 is integrally connected to the upper end of the taper portion 15, and the internal space of the body portion 11 and the large diameter portion 13 communicate with each other. The inner diameter of the large diameter portion 13 is set to 1.3 to 1.6 times the inner diameter of the body portion 11.
The reaction furnace 10 is supported in a state of being suspended from the support leg 16 by fixing the taper part 15 at the upper part of the body part 11 to the floor B by the support leg 16.

The raw material supply means 20 is made of metal from the raw material feed hopper 22 into the body portion 11 by air flow transfer using hydrogen chloride gas as a carrier gas via a raw material supply pipe 21 connected to the lower portion of the body portion 11 of the reaction furnace 10. Silicon powder P is supplied. In the body part 11, a stirrer 19 for stirring the internal space of the body part 11 is provided in the vicinity of the position where the metal silicon powder P is introduced.
The gas introduction means 30 introduces hydrogen chloride gas into the bottom 12 of the reaction furnace 10 through the gas supply pipe 31.

  A number of nozzles 17 extending in the vertical direction are fixed in a penetrating state in the partition wall 14 that divides the bottom portion 12 and the body portion 11 of the reaction furnace 10. These nozzles 17 are arranged in the body part 11 at the upper part and in the bottom part 12 at the lower part. Hydrogen chloride gas introduced into the bottom 12 of the reaction furnace 10 by the gas introduction means 30 is ejected into the body 11 through the nozzles 17.

  As shown in FIG. 2, the nozzle 17 has a shaft portion 17A that penetrates the partition wall 14, and a hexagonal bolt head-shaped head portion 17B formed at the upper end of the shaft portion 17A. A male screw is formed on the shaft portion 17 </ b> A, and a nut 17 </ b> C is screwed to the male screw on the lower surface side of the partition wall 14, whereby the nozzle 17 is fixed to the partition wall 14. A washer 17D is interposed between the nut 17C and the lower surface of the partition wall 14 and between the head 17B and the upper surface of the partition wall 14.

  The nozzle 17 is formed with a gas flow path 17a that communicates the lower end surface of the shaft portion 17A and the side surface of the head portion 17B. This gas flow path 17a has a spout 17b opened on each side surface of the head portion 17B, and a pressure equalizing pipe 17E is connected to the lower end side of the shaft portion 17A. The hydrogen chloride gas in the bottom 12 is supplied through the pressure equalizing pipe 17E, and is jetted into the body part 11 from the jet port 17b of the gas flow path 17a. The center of the jet port 17b is at a position of height h from the upper surface of the partition wall 14.

  As shown in FIG. 3, a plurality of gas diffusion materials 18 made of an iron-based material are provided on the partition wall 14. The gas diffusing material 18 includes a ball-shaped gas diffusing material 18A and a plate-shaped gas diffusing material 18B. The ball-shaped gas diffusing material 18A and the plate-shaped gas diffusing material 18B are mixed, and the head 17B of the nozzle 17 is mixed. It is laid down to cover the surroundings. As shown in FIG. 2, the radius r of the ball-shaped gas diffusion material 18A and the height h of the center of the ejection port 17b satisfy the relationship of h <r. As a result, the hydrogen chloride gas ejected from the ejection port 17b is ejected mainly toward the lower hemispherical surface of the ball-shaped gas diffusion material 18A, as indicated by arrows in FIG. 2, and this ball-shaped gas diffusion material 18A. Is diffused along the sphere.

  The plate-like gas diffusion material 18B has a disk shape having a through hole whose diameter is smaller than the diameter (= 2 × r) of the ball-like gas diffusion material 18A. Therefore, since the ball-shaped gas diffusion material 18A is disposed so as to fit into the through holes of the plate-shaped gas diffusion material 18B, a gap is formed between the ball-shaped gas diffusion materials 18A. Furthermore, since the plate-like gas diffusion material 18B is moved by the pressure of the hydrogen chloride gas to be ejected, and the ball-shaped gas diffusion material 18A is also moved accordingly, an irregular gas flow path is formed.

  The stirrer 19 is provided above the layer of the gas diffusion material 18 and is stirred so as to mix the hydrogen chloride gas ejected through the gas passage formed between the gas diffusion materials 18 and the metal silicon powder P. To do.

  The gas extraction means 40 sends the reaction fluid containing trichlorosilane discharged from the reaction furnace 10 to the gas purification system 42 via the cyclone 41. The cyclone 41 collects the metal silicon powder discharged together with the reaction fluid. The collected metal silicon powder is returned to the raw material feed hopper 22 through the recovery pipe 43 and is again charged into the reaction furnace 10.

A method for producing trichlorosilane by the trichlorosilane production apparatus 100 configured as described above will be described.
Hydrogen chloride gas is introduced from the gas introduction means 30 into the bottom 12 of the reaction furnace 10. The hydrogen chloride gas introduced into the bottom portion 12 is diffused by the gas diffusion material 18 through the nozzle 17 provided so as to communicate between the bottom portion 12 and the body portion 11 of the reaction furnace 10, and is uniformly distributed in the body portion 11. Is erupted.

  The metal silicon powder P is supplied from the raw material supply means 20 to the body portion 11 of the reaction furnace 10 by air flow transfer using hydrogen chloride gas as a carrier gas. At this time, the supply amount of the metal silicon powder P is adjusted by controlling the flow rate of the carrier gas.

  The metal silicon powder P supplied to the body portion 11 rides on the rising flow of hydrogen chloride gas ejected from below, and reacts while flowing while being stirred by the stirrer 19. At this time, since the hydrogen chloride gas is uniformly diffused and ejected, the hydrogen chloride gas and the metal silicon powder P react while flowing in a uniformly mixed state, thereby generating a gas containing trichlorosilane. To do.

  Since the reaction between the metal silicon powder P and the hydrogen chloride gas is an exothermic reaction, the fluid mixture becomes a high temperature and rises in the center of the body portion 11. At this time, the hydrogen chloride gas is bubbled and present in the fluid mixture.

  Then, the trichlorosilane gas that has risen to the top of the reaction furnace 10 is discharged from the top of the reaction furnace 10 to the gas extraction means 40. Here, since the inner diameter of the reaction furnace 10 becomes larger than the body part 11 from the tapered part 15 to the large diameter part 13 in the upper part of the reaction furnace 10, the flow rate of the fluid that rises as the pressure decreases is decreased. For this reason, the unreacted metal silicon powder P falls by its own weight in the vicinity of the tapered portion 15. Thereby, the metal silicon powder P is separated from the fluid mixture, and the gas containing trichlorosilane is taken out from the upper part of the reaction furnace 10.

  As described above, according to the trichlorosilane manufacturing apparatus of the present invention, since the ejection port is arranged toward the lower hemispherical surface of the ball-shaped gas diffusion material, the ejection port is blocked by the ball-shaped gas diffusion material. And the hydrogen chloride gas can be efficiently diffused by the ball-shaped gas diffusion material. Further, the plate-shaped gas diffusion material having a through-hole that does not allow the ball-shaped gas diffusion material to pass therethrough facilitates securing a space between the ball-shaped gas diffusion materials, and the plate-like gas diffusion material and the ball-shaped gas are formed by the hydrogen chloride gas ejection pressure. When the gas diffusion material moves, an irregular gas flow path is formed between the plate-like gas diffusion material and the ball-like gas diffusion material, so that hydrogen chloride gas can be supplied to the reaction furnace without unevenness. . Accordingly, it is possible to improve the production efficiency of trichlorosilane by reacting the metal silicon powder and hydrogen chloride gas in a state of being mixed evenly.

  In addition, this invention is not limited to the thing of the structure of the said embodiment, In a detailed structure, it is possible to add a various change in the range which does not deviate from the meaning of this invention. In the above embodiment, a gas diffusion material made of an iron-based material is used. However, the material of the gas diffusion material is preferably a material having corrosion resistance against hydrogen chloride, such as ceramics, stainless steel, or general steel material. It may be. Further, the plate-like gas diffusion material is a disc shape in the embodiment, but may be a square plate shape or the like. Also in this case, it is preferable that the size of the through hole is smaller than that of the ball-shaped gas diffusion material.

  In the above embodiment, the diameter r of the ball-shaped gas diffusion material 18A and the height h from the upper surface of the partition wall 14 at the center of the nozzle 17b of the nozzle 17 satisfy the relationship of h <r. r may be different from the height h. That is, in the trichlorosilane apparatus of the present invention, as shown in FIGS. 4 and 5, a gas diffusion material 18A and a nozzle 17 that satisfy the relationship of h> r may be used. In this case, the hydrogen chloride gas ejected from the ejection port 17b is ejected toward the upper hemispherical surface of the ball-shaped gas diffusion material 18A, as indicated by arrows in FIGS. 4 and 5, and this ball-shaped gas diffusion material. It is diffused along the 18A spherical surface. Further, a gas diffusion material satisfying h> r and a gas diffusion material satisfying h <r may be mixed and used. Since the diameter does not coincide with the height of the ejection port, the ball-shaped gas diffusing material does not block the ejection port, so that hydrogen chloride gas can be reliably ejected.

  Furthermore, as shown in FIG. 4, by forming the tapered portion 17c at the ejection port 17b, the gas ejection direction can be widened. Thereby, even when the height h of the ejection port 17b is larger than the radius r, gas can be efficiently diffused also to the lower hemispherical surface side of the ball-shaped gas diffusion material 18A.

DESCRIPTION OF SYMBOLS 100 Manufacturing apparatus 10 Reaction furnace 11 Body part 12 Bottom part 13 Large diameter part 14 Partition 15 Tapered part 16 Support leg 17 Nozzle 17A Shaft part 17B Head part 17C Nut 17D Washer 17E Pressure equalizing pipe 17a Gas flow path 17b Jet outlet 17c Tapered part 18 Gas Diffusion material 18A Ball-shaped gas diffusion material 18B Plate-shaped gas diffusion material 19 Stirrer 20 Raw material supply means 21 Raw material supply pipe 22 Raw material feed hopper 30 Gas introduction means 31 Gas supply pipe 40 Gas extraction means 41 Cyclone 42 Gas purification system 43 Recovery pipe B Floor P Metallic silicon powder h Height r Radius

Claims (1)

A trichlorosilane production apparatus for reacting metal silicon powder supplied into a reaction furnace while flowing with hydrogen chloride gas, and taking out trichlorosilane produced by the reaction from the reaction furnace,
The reactor is
A body part to which the metal silicon powder is supplied;
A bottom portion provided continuously to the lower portion of the body portion and supplied with the hydrogen chloride gas;
A partition partitioning the body part and the bottom part,
A nozzle having a spout attached to the partition wall and spouting the hydrogen chloride gas supplied to the bottom portion into the body portion;
A plurality of ball-shaped gas diffusion materials having a radius different from the height from the top surface of the partition wall and a plurality of plate-shaped gas diffusion materials having through holes are mixed on the partition wall . An apparatus for producing trichlorosilane, which is laid so as to cover the periphery .

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