WO2010103631A1

WO2010103631A1 - Apparatus for producing trichlorosilane

Info

Publication number: WO2010103631A1
Application number: PCT/JP2009/054664
Authority: WO
Inventors: 靖史松尾; 晃一竹村
Original assignee: 電気化学工業株式会社
Priority date: 2009-03-11
Filing date: 2009-03-11
Publication date: 2010-09-16
Also published as: TW201036913A

Abstract

Disclosed is an apparatus having excellent heat resistance, which is used for producing trichlorosilane. The apparatus for producing trichlorosilane comprises a reactor (1) which is provided with a reaction chamber (10) wherein a reaction product gas containing trichlorosilane and hydrogen chloride is produced from a raw material gas containing tetrachlorosilane and hydrogen, a heater (11) for heating the reaction chamber (10), and an outer cylindrical case (12) for housing the reaction chamber (10) and the heater (11); a quenching tower (4) for cooling the reaction product gas; a connection cylinder (3) provided with a first bellows pipe (30) which expandably/contractibly connects the reactor (1) and the quenching tower (4); an extraction pipe (2) so arranged from the reaction chamber (10) to the quenching tower (4) passing through inside of the connection cylinder (3) as to guide the reaction product gas from the reactor (1) to the quenching tower (4); and a second bellows pipe (31) arranged substantially coaxially with the extraction pipe (2) within the connection cylinder (3) so as to cover the extraction pipe (2), while having one end joined to the inner circumferential surface of the connection cylinder (3) and the other end joined to the outer circumferential surface of the extraction pipe (2).

Description

Trichlorosilane production equipment

The present invention relates to a trichlorosilane production apparatus excellent in heat resistance, in which tetrachlorosilane and hydrogen are reacted to convert to trichlorosilane.

Trichlorosilane (SiHCl ₃ ) is a special material gas used for manufacturing semiconductors, liquid crystal panels, solar cells, and the like. In recent years, demand has been steadily expanding, and growth is expected as a CVD material widely used in the electronics field.

Trichlorosilane is produced by contacting tetrachlorosilane (SiCl ₄ ) and hydrogen (H ₂ ) to achieve the following thermal equilibrium state.
SiCl ₄ + H ₂ ⇔SiHCl ₃ + HCl (1)
This reaction is performed by heating a raw material gas composed of gasified tetrachlorosilane and hydrogen to 800 ° C. to 1300 ° C. in a reaction vessel.

The high temperature reaction product gas discharged from the reaction vessel contains a large amount of unreacted tetrachlorosilane and hydrogen in addition to the generated trichlorosilane and hydrogen chloride. In order to extract trichlorosilane from the reaction product gas, a method of condensing in a distillation column using the difference in boiling point between tetrachlorosilane and trichlorosilane is used. Specifically, in the condenser, it is divided into a chlorosilane that is a condensed component and hydrogen chloride, hydrogen, and an uncondensed chlorosilane that is an uncondensed component, and further cooled to about −70 ° C. by deep-cooling separation, and then trichlorosilane from the condensed component Isolate.

When separating the target trichlorosilane from the reaction product gas, if the high-temperature reaction product gas just introduced from the reaction vessel is suddenly introduced into the distillation column, an excessive load is applied to the distillation column. Before the reaction product gas is introduced into the distillation tower, it is necessary to preliminarily cool it in the quenching tower.

However, even if it is preliminary cooling, if the cooling power is insufficient, the equilibrium is inclined to the tetrachlorosilane side, and once generated trichlorosilane returns to tetrachlorosilane again. Therefore, in order to improve the recovery efficiency of trichlorosilane, it is necessary to cool the reaction product gas to a predetermined temperature as quickly as possible when the equilibrium sufficiently reaches the trichlorosilane side and freeze the equilibrium. In order to instantly freeze the equilibrium state, it is typically necessary to rapidly cool the reaction product gas to about 600 ° C. in less than one second.

As a reaction vessel equipped with a mechanism for reacting tetrachlorosilane with hydrogen to convert to trichlorosilane and further cooling the reaction product gas, there is one described in Patent Document 1, for example. In this document, a reaction product gas containing trichlorosilane and hydrogen chloride is obtained by introducing tetrachlorosilane and hydrogen into a reaction chamber and performing a conversion reaction at a temperature of 600 ° C. to 1200 ° C., and then derived from the reaction chamber. There has been proposed an apparatus provided with a cooling means for bringing the chlorosilane mixture cooled to room temperature into contact with the reaction product gas by spraying and rapidly cooling to 300 ° C. or less within 1 second.

In Patent Document 2, a gas mixture having a molar ratio of SiCl ₄ and H ₂ of 1: 1 to 1: 2 is introduced into a reactor heated to a temperature of 1200 ° C. over 1200 ° C. and reacted to cause a thermal equilibrium state. (Molar ratio of SiCl ₄ and H _{2 in} the equilibrium mixture is 1: 1 to 1: 4), and the mixture containing SiHCl ₃ and HCl is rapidly cooled to 600 ° C. or less within 1 second. A process for producing SiHCl ₃ is described that improves the yield and yield of SiHCl ₃ by freezing the reaction.

Japanese Patent Publication No.57-38524 JP 60-81010 A

Summary of the Invention

By the way, in the apparatus described in Patent Document 1, the reaction furnace and the quenching tower are connected via a connection pipe provided on the side of the quenching tower, and the connection between the connection pipe and the reaction furnace is closed. An end is formed. A sound is passed through the closed end, and the reaction gas generated in the reaction furnace is led to the quenching chamber through the sound.

However, the reactor wall that reaches the high temperature and the low-temperature quenching chamber are blocked by the closed end wall at the junction between the connecting pipe and the reactor, and therefore the end wall that blocks the quenching tower and the reactor. There is a large temperature difference locally in the vicinity of it. As a result, stress due to thermal expansion concentrates on the part, which may cause distortion or breakage. Moreover, even if the sound that penetrates and is fixed to the end wall surface is thermally expanded, stress may be concentrated on the joint between the sound and the end wall surface, resulting in distortion or breakage.

Moreover, in the apparatus described in Patent Document 2, a take-out pipe for leading out reaction product gas, for example, a capillary tube or a lapar pipe, is inserted into the exhaust side end of the reactor, and the take-out pipe and the exhaust side end of the reactor The joint with the part is airtightly fixed so that the reaction product gas does not leak. The reaction product gas is naturally cooled as it passes through the take-out pipe.

However, in the apparatus having the above-described configuration, cooling of the reaction product gas is left to natural cooling when passing through the take-out pipe, so that it cannot always be said that the cooling rate and the cooling capacity are sufficient. Further, when the exhaust side end portion of the reactor or the take-out pipe fixed through it is thermally expanded, stress is applied to these joint portions, which may cause distortion or breakage.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an apparatus for producing trichlorosilane capable of preventing distortion and breakage due to thermal expansion at a connecting portion between a reaction furnace and a quenching tower. More specifically, a connecting cylinder that connects a reaction furnace that generates a reaction gas under a high temperature condition and a quenching tower that cools the reaction gas, a blocking member that blocks a space between the reaction furnace and the quenching tower in the connection cylinder, In addition, in the extraction pipe for leading the reaction product gas from the reaction vessel accommodated in the reaction furnace to the quenching tower through the inside of the connecting cylinder, the stress generated by the thermal expansion is absorbed and the stress is generated by the thermal expansion. An object of the present invention is to provide an apparatus for producing trichlorosilane that reduces the above-described problem.

The present invention employs the following configuration in order to solve the above problems. That is, the trichlorosilane production apparatus of the present invention is
A reaction vessel for producing a reaction product gas containing trichlorosilane and hydrogen chloride from a raw material gas containing tetrachlorosilane and hydrogen, a heater for heating the reaction vessel, and an outer cylinder vessel for housing the reaction vessel and the heater. A reactor equipped with,
A quenching tower for cooling the reaction product gas;
A connecting cylinder including a first bellows pipe that connects the reaction furnace and the quenching tower in an extendable manner;
An extraction pipe arranged from the reaction vessel to the quenching tower through the inside of the connecting cylinder, and leading the reaction product gas from the reaction furnace to the quenching tower;
A second bellows pipe disposed substantially coaxially so as to cover the extraction pipe inside the connection cylinder, one end joined to the inner periphery of the connection cylinder, and the other end joined to the outer periphery of the extraction pipe. It is characterized by being.

In this trichlorosilane manufacturing apparatus, the connecting cylinder connecting the reactor and the quenching tower includes the first bellows pipe having the bellows structure, so that stress generated by thermal expansion when heat is applied to the connecting cylinder is reduced. Absorption can be achieved by changing the shape of one bellows tube. Therefore, damage due to thermal expansion of the connecting cylinder can be prevented, and the stability and safety of the apparatus can be improved.

Furthermore, since the space inside the reactor and the space inside the quenching tower are blocked by the second bellows pipe disposed almost coaxially between the extraction pipe and the connecting cylinder, the extraction pipe is heated. Even if it expand | swells, the 2nd bellows pipe | tube which is a interruption | blocking means can follow this, can be expanded-contracted suitably, and can absorb this. Therefore, it is possible to prevent the extraction tube and the shut-off means from being damaged due to thermal expansion, to improve the stability and safety of the apparatus, and to maintain the airtight state between both towers more stably. .

In addition, the double bellows tube provided at the connection between the reaction furnace and the quenching tower can absorb stress generated due to causes other than thermal expansion. Therefore, for example, it is excellent also in earthquake resistance.

Furthermore, since the space in the high temperature outer cylinder container and the space in the low temperature quenching tower are blocked by the second bellows pipe, heat exchange is performed inside and outside the second bellows pipe. In the present invention, since the second bellows pipe is arranged substantially coaxially so as to cover the extraction pipe inside the connecting cylinder, the temperature is increased from the outer cylinder container side to the quenching tower side along the second bellows pipe. An intermediate temperature zone that gradually falls can be formed. As a result, the thermal load applied to the extraction pipe can be widely distributed over the band, and a large stress can be prevented from being locally generated in the extraction pipe.

According to the trichlorosilane production apparatus according to the present invention, the connecting cylinder connecting the reaction furnace and the quenching tower includes the first bellows pipe, and the reaction furnace and the quenching tower are substantially coaxial with the extraction pipe in the connecting cylinder. Since it is interrupted | blocked by the 2nd bellows pipe | tube arrange | positioned by these, the damage by thermal expansion in these parts can be prevented, and stability and safety | security of an apparatus can be improved.

And, more particularly, according to the trichlorosilane manufacturing apparatus according to the present invention, by arranging the second bellows pipe so as to cover the extraction pipe inside the connection cylinder, an intermediate temperature is provided inside the connection cylinder. Since a zone is formed and the thermal load applied to the extraction pipe can be dispersed, it is possible to prevent a large stress from being locally generated in the extraction pipe.

It is explanatory drawing of the trichlorosilane manufacturing apparatus which is embodiment of this invention. It is a schematic longitudinal cross-sectional view of the connection cylinder periphery of the trichlorosilane manufacturing apparatus which is embodiment of this invention.

Explanation of symbols

1: Reaction furnace 2: Extraction pipe 3: Connecting cylinder 4: Rapid cooling tower 10: Reaction vessel 11: Heater 12: Outer cylinder vessel 13: Raw material gas inlet 14: Reaction product gas outlet 15: Heating element 16: Electrode 17 : Source gas introduction opening 18: Reaction product gas extraction opening 21: First member 22: Second member 23: Third member 24: Reaction product gas blowout part 25: Protrusion part 30: First bellows pipe 31: First Double bellows tube 32: first tubular member 33: second tubular member 34: accommodating portion 35: upright portion 36: diameter-expanding portion 37: edge portion 38: flange portion 39: plate material 40: metal container 41: spray nozzle 42: Pump 43: Cooling device 44: Conduit 45: Reaction product gas introduction opening

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

FIG. 1 schematically shows an embodiment of a trichlorosilane production apparatus according to the present invention. FIG. 2 schematically shows a cross section around the connecting cylinder of the trichlorosilane production apparatus.

As shown in FIG. 1 and FIG. 2, the trichlorosilane production apparatus of this embodiment is
A reaction vessel 10 for generating a reaction product gas containing trichlorosilane and hydrogen chloride from a raw material gas containing tetrachlorosilane and hydrogen, a heater 11 for heating the reaction vessel 10, and the reaction vessel 10 and the heater 11 are accommodated. A reactor 1 comprising an outer tube container 12;
A quenching tower 4 for cooling the reaction product gas;
A connecting cylinder 3 having a first bellows pipe 30 that connects the reaction furnace 1 and the quenching tower 4 in an extendable manner;
An extraction pipe 2 that is arranged so as to reach the quenching tower 4 from the reaction vessel 10 through the inside of the connecting cylinder 3, and leads the reaction product gas from the reaction furnace 1 to the quenching tower 4;
A second bellows pipe disposed substantially coaxially so as to cover the extraction pipe 2 inside the connection cylinder 3, one end joined to the inner periphery of the connection cylinder 3, and the other end joined to the outer periphery of the extraction pipe 2. 31.

<Reactor>
The reaction furnace 1 includes a reaction vessel 10, a long heater 11 disposed so as to surround the outside of the reaction vessel 10, and the outer vessel 12 that accommodates the reaction vessel 10 and the heater 11. By heating the outer wall of the reaction vessel 10 with the heater 11, the mixed gas of tetrachlorosilane and hydrogen supplied from the raw material gas inlet 13 provided at the bottom of the reaction vessel 10 is about 800 ° C. inside the reaction vessel 10. The reaction is performed at a high temperature of about 1300 ° C. to produce a reaction product gas containing trichlorosilane and hydrogen chloride.

<Reaction vessel>
The reaction vessel 10 is a substantially cylindrical vessel for reacting tetrachlorosilane and hydrogen in a high temperature environment, a raw material gas inlet 13 for taking in a raw material gas, and a reaction product for deriving a reaction product gas. And a gas outlet 14. In the present embodiment, the raw material gas inlet 13 is provided in the center of the bottom of the reaction vessel 10 and the reaction product gas outlet 14 is provided on the upper side wall of the reaction vessel 10, but these installation positions are limited to this. It is not something.

The material constituting the reaction vessel 10 is a graphite material having excellent airtightness, and particularly has high strength due to the fine particle structure, and the characteristics such as thermal expansion are the same in any direction, so that it has heat resistance and corrosion resistance. It is preferable to use isotropic high-purity graphite, which is also excellent.

In particular, it is preferable that the inner peripheral surface and / or the outer peripheral surface of the reaction vessel 10 is treated with a silicon carbide coating, and the silicon carbide coating is formed with a thickness of 10 to 500 μm by a CVD method. Since the silicon carbide coating has a very high resistance to chemical degradation, chemical erosion of the carbon structure can be prevented. Therefore, the surface of the reaction vessel 10 can be protected from corrosion by performing the silicon carbide coating treatment.

<Heater>
The heater 11 includes a plurality of elongated carbon heating elements 15 extending in the vertical direction and an electrode 16 connected to one end of the heating element 15 for supplying power to the heating element 15. The heater 11 is arranged so as to surround the reaction vessel 10 in a plurality, and controls the temperature inside the reaction vessel 10 from the outside of the reaction vessel 10 by controlling the amount of power supplied.

<Outer cylinder container>
The outer cylinder container 12 is a substantially cylindrical container whose outer side is made of a metal such as stainless steel and whose inner side is covered with a heat insulating material such as a carbon board, a refractory brick, or a heat insulating brick. The outer cylinder container 12 accommodates the reaction container 10 and the heater 11 and insulates them from the outside. When the reaction vessel 10 is accommodated in the outer cylinder vessel 12, the source gas introduction opening 17 and the reaction product gas extraction opening 18 are respectively located at positions corresponding to the source gas introduction port 13 and the reaction product gas extraction port 14. Is provided. The reaction product gas extraction opening 18 is provided with joint means such as a flange, and can be connected to a connecting cylinder 3 described later.

<Connecting cylinder>
The connecting cylinder 3 of this embodiment is
A first cylindrical member 32 having a coupling means connected to the reaction product gas extraction opening 18 of the reaction furnace 1 at one end and an accommodating portion 34 having an enlarged diameter at the other end;
A second tubular member 33 having an insertion side end inserted into the accommodating portion 34 side of the first tubular member 32 at one end and joint means connected to the quenching tower 4 at the other end;
A first bellows pipe 30 that is housed in the housing portion 34 and has one end fixed to the end portion on the housing portion 34 side of the first cylindrical member 32 and the other end fixed to the insertion side end portion of the second tubular member 33. I have.

<First cylindrical member>
The first cylindrical member 32 is made of a metal such as stainless steel, and has a joint means such as a flange that can be connected to the reaction product gas extraction opening 18 of the outer cylinder container 12 at one end, and a first bellows pipe at the other end. A housing portion 34 for housing 30 is provided. The accommodating portion 34 includes an upright portion 35 that extends perpendicularly outward in the radial direction of the first cylindrical member 32, a diameter-expanded portion 36 that extends from the upright portion 35 along the axial direction, and a diameter from the diameter-expanded portion 36. It consists of the edge part 37 extended | stretched perpendicularly | vertically to a direction inner side.

The edge portion 37 is a portion for fixing one end of the first bellows tube 30, and the projecting width inward in the radial direction of the edge portion 37 is the second cylindrical member as long as one end of the first bellows tube 30 can be fixed. It is set as a range that does not prevent the insertion of 33 and does not prevent the inserted second cylindrical member 33 from freely moving in the axial direction and the radial direction.

<Second cylindrical member>
The second cylindrical member 33 is made of a metal such as stainless steel like the first cylindrical member 32, and has a joint means such as a flange for connecting to a reaction product gas introduction opening 45 of the quenching tower 4 to be described later at one end. The other end (the insertion side end inserted into the accommodating portion 34 side of the first cylindrical member 32) has a flange portion 38 extending perpendicularly to the radially outer side of the second cylindrical member 33.

The flange portion 38 is a portion for fixing one end of the first bellows tube 30, and the protruding width of the flange portion 38 to the outer side in the radial direction is the first cylindrical member as long as one end of the first bellows tube 30 can be fixed. The second cylindrical member 33 is in a range that does not prevent the second cylindrical member 33 from freely moving in the axial direction and the radial direction while being inserted into the first cylindrical member 32.

<First bellows tube>
The first bellows tube 30 is a member having a cylindrical bellows structure made of metal, and can be expanded and contracted in the axial direction and can also be deformed in the radial direction. The first bellows tube 30 may be made of metal, but is more preferably made of stainless steel, and may be made of austenitic stainless steel or ferritic stainless steel.

The first bellows tube 30 preferably has a peak height of about 2 to 10% of the inlet diameter and a distance between the peaks of about 2 to 8% of the total length. Further, it is preferable that the amount of displacement in the direction perpendicular to the axis is 3 to 10% of the inlet diameter of the first bellows tube 30, and the amount of displacement in the axial direction is about 2 to 5% of the total length. Further, the intervals and heights of the peaks may be uniform or non-uniform.

In the connecting cylinder 3 configured as described above, the first bellows tube 30 is stored in the accommodating portion 34 of the first cylindrical member 32, and both ends thereof are the edges 37 of the first cylindrical member 32 and the second cylindrical member 33. It is set as the structure fixed to the opposing surface of the collar part 38, respectively. Therefore, the inside of the first bellows tube 30 is covered with the body portion of the second cylindrical member 33.

To assemble the connecting cylinder 3 having the above-described configuration, for example, both ends of the first bellows pipe 30 are fixed to the edge portion 37 of the first cylindrical member 32 and the flange portion 38 of the second cylindrical member 33, respectively. The first bellows tube 30 may be stored in the accommodating portion 34 by inserting the second cylindrical member 33 into the first cylindrical member 32. Moreover, it is good also as a structure which attaches the member corresponded to the edge part 37 of the 1st cylindrical member 32 separately.

<Quenching tower>
The quenching tower 4 includes a cylindrical metal container 40, a spray nozzle 41 that is installed in the container and sprays the coolant in the container, and the coolant accumulated in the bottom of the container is taken out and circulated to the spray nozzle 41. A cooling pump 43 for cooling the coolant, and a conduit 44 for taking out the reaction product gas after cooling from the top of the quenching tower 4. A reaction product gas introduction opening 45 for connecting the connecting cylinder 3 is provided on the side wall of the quenching tower 4. The reaction product gas introduction opening 45 has a flange or the like for connecting to the connection cylinder 3. Joint means are provided. The spray nozzle 41 is installed in the vicinity of the upper portion of the reaction product gas introduction opening 45 so that the coolant can be sprayed toward the reaction product gas introduced into the quenching tower 4.

The cooling liquid is composed of a mixed liquid of trichlorosilane and tetrachlorosilane, and the ratio of tetrachlorosilane to the total amount of tetrachlorosilane and trichlorosilane is 1 to 0.5. The temperature is preferably 60 ° C. or lower. For example, a tetrachlorosilane: trichlorosilane composition ratio of 85:15 and a temperature of about 40 ° C. can be preferably used.

The cooled reaction product gas taken out from the top of the quenching tower 4 is further sent to a distillation tower (not shown) through a conduit 44, and the intended trichlorosilane is separated.

<Extraction pipe>
The extraction pipe 2 is a carbon tubular member that connects the inside of the reaction vessel 10 and the inside of the quenching tower 4 through the inside of the connecting cylinder 3, and guides the reaction product gas in the reaction vessel 10 to the quenching tower 4.

The material constituting the extraction pipe 2 is a graphite material having excellent airtightness, and particularly has high strength due to the fine particle structure, and has the same characteristics such as thermal expansion in any direction. It is preferable to use isotropic high-purity graphite that is also excellent in corrosion resistance.

In particular, it is preferable that the inner peripheral surface and / or the outer peripheral surface of the extraction pipe 2 is treated with a silicon carbide coating, and that the silicon carbide coating is formed with a thickness of 10 to 500 μm by a CVD method. Since the silicon carbide coating has a very high resistance to chemical degradation, chemical erosion of the carbon structure can be prevented. Therefore, the surface of the extraction pipe 2 can be protected from corrosion by performing the silicon carbide coating treatment.

The extraction tube 2 is preferably made of a single member because it is excellent in terms of airtightness and strength, but it may be formed by connecting a plurality of members. The extraction pipe 2 of the present embodiment is composed of a plurality of members, and when the apparatus is assembled, the first member 21 mainly located in the reaction furnace 1 and the second member mainly located in the connecting cylinder 3. 22 and a third member 23 mainly located in the cooling tower. That is, the first member 21 has a connecting portion with one end of the reaction product gas outlet 14 of the reaction vessel 10 at one end and a joint means for connecting the second member 22 at the other end. The joint member for connecting the first member 21 or the third member 23 is connected to both ends, and the third member 23 has the joint means for connecting the second member 22 to one end, and the reaction is generated at the other end. A gas blowing part 24 is provided.

The joint means of the extraction pipe 2 is such that a protruding portion 25 is formed on the outer peripheral side of the extraction pipe 2 so that a second bellows pipe 31 described later is joined. As a joint means for forming such a protrusion 25, a flange can be typically used. Alternatively, a substantially cylindrical tubular member may be used and the butted end portion may be screwed and fastened from the outside with a ring. In this case, the ring forms a protrusion 25 for fixing the second bellows pipe 31.

<Second bellows tube>
The second bellows tube 31 is a member having a bellows structure made of metal, and can be expanded and contracted in the axial direction and can also be deformed in the radial direction. Similar to the first bellows pipe 30, the second bellows pipe 31 may be made of metal, but is more preferably made of stainless steel, and may be made of austenitic stainless steel or ferritic stainless steel. Moreover, although it may be a single layer or a multilayer, a multilayer structure is preferable because corrosion resistance is increased.

The second bellows pipe 31 preferably has a peak height of about 2 to 10% of the inlet diameter and a distance between the peaks of about 2 to 8% of the total length. Further, it is preferable that the amount of displacement in the direction perpendicular to the axis is 3 to 10% of the inlet diameter of the second bellows pipe 31, and the amount of displacement in the axial direction is about 2 to 5% of the total length. Further, the intervals and heights of the peaks may be uniform or non-uniform.

The second bellows pipe 31 is arranged substantially coaxially so as to cover the outside of the extraction pipe 2 inside the connection cylinder 3, one end is joined to the inner periphery of the connection cylinder 3, and the other end is the extraction pipe 2. Joined to the outer periphery.
In the present embodiment, the connection between the second bellows pipe 31 and the inner periphery of the connecting cylinder 3 is performed by the joint means provided in the reaction product gas extraction opening 18 of the outer cylinder container 12 and the first cylindrical member of the connecting cylinder 3. The doughnut-shaped plate member 39 is sandwiched between the joint means provided at 32 and one end of the second bellows pipe 31 is fixed to a portion of the plate member 39 protruding into the connecting tube 3. In addition, the connection between the second bellows pipe 31 and the outer periphery of the extraction pipe 2 is such that the second bellows pipe is connected to the projecting portion 25 formed at the connecting portion between the second member 22 and the third member 23 constituting the extraction pipe 2. This is done by fixing one end of 31.
In this way, the space inside the reaction furnace 1 and the space inside the quenching tower 4 are blocked by the second bellows pipe 31 arranged in the connecting cylinder 3.

In the present embodiment, since the members constituting the connecting cylinder 3 are connected by the first bellows pipe 30 which can be expanded and contracted, a large temperature difference is locally applied to the connecting cylinder 3 and the first cylindrical member 32 and the second cylindrical member 32. Even if the cylindrical member 33 is thermally expanded, the stress relating to the connecting cylinder 3 can be absorbed by the shape of the first bellows tube 30 being changed, and the distortion or breakage of the connecting cylinder 3 can be avoided.

Further, since the outer side of the first bellows tube 30 is covered with the enlarged diameter portion 36 of the first cylindrical member 32 and the inner side is covered with the body portion of the second cylindrical member 33, chemicals that may exist inside the connecting cylinder 3. It is possible to prevent a substance, that is, a reactive substance contained in the reaction product gas or the cooling liquid from adhering to the first bellows pipe 30 and deteriorating it, thereby impairing the stretchability.

In addition, a second bellows pipe 31 that can be expanded and contracted is used as a means that is connected between the inner periphery of the connecting cylinder 3 and the outer periphery of the extraction pipe 2 to block the space inside the reactor 1 and the space inside the quenching tower 4. Therefore, even if the extraction pipe 2 is thermally expanded or contracted, the second bellows pipe 31 is appropriately expanded and contracted following this, so that the extraction pipe 2 is not damaged and the shut-off state of both spaces is broken. There is nothing.

Further, since the second bellows pipe 31 is arranged substantially coaxially with the extraction pipe 2 so as to cover the extraction pipe 2 inside the connecting cylinder 3, the quenching tower from the outer cylinder container 12 side along the second bellows pipe 31. An intermediate temperature zone can be formed in which the temperature gradually decreases toward the side 4. As a result, the thermal load applied to the extraction pipe 2 can be widely distributed over the band, and it is possible to prevent a large stress from being locally generated in the extraction pipe 2.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, it is preferable that the reaction vessel is originally integrally molded in order to achieve excellent durability and heat transfer efficiency. However, due to problems in manufacturing technology, a reaction vessel in which a plurality of substantially cylindrical bodies are connected and integrated is used. It is done. As a reaction vessel for connecting and integrating a plurality of substantially cylindrical bodies, in particular, a plurality of substantially cylindrical bodies are arranged substantially vertically on the same end, but end to end with each other, and the abutting ends are screwed and fastened from the outside with a ring. Is preferred. By adopting such a structure, the structure of the substantially cylindrical body can be simplified, and since a thin portion is not formed at the upper end or the lower end, it has excellent resistance to physical impact. In addition, since the end portion of one substantially cylindrical body is not fitted to the end portion of the other substantially cylindrical body in the connecting portion, even if the substantially cylindrical body is thermally expanded by using it in a high temperature environment. In addition, there is no possibility of causing cracks or cracks in the connecting portion due to the difference in thermal expansion coefficient between individual substantially cylindrical bodies. Therefore, the frequency of exchanging the components of the reaction vessel is reduced, and the working efficiency of the apparatus can be improved.

Moreover, in the said embodiment, although the 1st bellows pipe was stored in the accommodating part of the 1st cylindrical member, and the inside was covered with the trunk | drum part of the 2nd cylindrical member, If the first bellows tube is used in the connecting portion with the second cylindrical member, the stress applied to the connecting tube can be sufficiently absorbed, so that the first bellows tube is the first cylindrical member and the second cylindrical member. It does not need to be accommodated between the members.

In the above embodiment, the reactor side end of the second bellows pipe is connected to the connecting cylinder, and the quench tower side end is connected to the extraction pipe. I do not care. That is, the connection between the second bellows pipe and the inner side of the connecting cylinder is made by using a joint means provided at the reaction product gas introduction opening of the quenching tower of the outer cylinder container and a joint means provided at the second cylindrical member of the connecting cylinder; The doughnut-shaped plate material is sandwiched between the two, and one end of the second bellows tube is fixed to the portion of the plate material that protrudes into the connecting tube, and the connection between the second bellows tube and the outside of the extraction tube is extracted. You may perform by fixing the end of a 2nd bellows pipe | tube to the protrusion part formed in the connection part of the 1st member and 2nd member which comprise a pipe | tube.

Furthermore, in the above embodiment, the extraction pipe is composed of three members, but it may be composed of a single member or a larger number of members.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited thereto.

Example 1
Trichlorosilane was manufactured using the trichlorosilane manufacturing apparatus shown in FIG. 2, and the presence or absence of distortion or breakage in the connecting tube, the extraction tube, and the second bellows tube was examined.

<Device description>
The following members were used for this apparatus.

Connecting cylinder:
A connecting cylinder in which stainless steel cylindrical members were connected via a stainless steel bellows tube (thickness: 2 mm) was used. The amount of displacement in the direction perpendicular to the axis of the bellows tube was about 5% of the inlet diameter, and the amount of displacement in the axial direction was about 5% of the total length.

Second bellows tube:
A stainless steel bellows tube was used. The amount of displacement in the direction perpendicular to the axis of the bellows tube was about 5% of the inlet diameter, and the amount of displacement in the axial direction was about 5% of the total length.

Extraction pipe:
A carbon tubular member subjected to a silicon carbide coating treatment was used.

<Experimental conditions>
Using the above apparatus, the reaction gas of tetrachlorosilane and hydrogen (mole = 1: 1) is reacted at normal pressure at a reaction temperature of 1100 ° C. in the reaction furnace, and the reaction product gas is quenched through an extraction pipe. And cooled using a cooling liquid whose temperature was adjusted to 20 ° C. (trichlorosilane concentration 20%).

After this trichlorosilane production apparatus was continuously operated for 2000 hours, the apparatus was disassembled and the connecting cylinder, the extraction pipe, and the second bellows pipe were observed, and no distortion or breakage was observed in any of the members. .

Comparative Example 1
A trichlorosilane production apparatus was prepared in the same manner as in Example 1 except that a cylindrical member (thickness: 2 mm) having no bellows structure was disposed instead of the second bellows pipe. This cylindrical member is made of the same material as the second bellows pipe used in the first embodiment.

When this trichlorosilane production apparatus was operated in the same manner as in Example 1, the apparatus was disassembled, and the connecting cylinder, the extraction pipe, and the cylindrical member were observed. As a result, distortion was observed in the extraction pipe and the cylindrical member. It was.

Comparative Example 2
Instead of the second bellows pipe, a plate-like member (thickness: 2 mm) having an opening through which the extraction pipe can penetrate was used to block the space on the reactor side and the space on the quenching tower near the center of the connecting cylinder. A trichlorosilane production apparatus was prepared in the same manner as in Example 1 except that. This cylindrical member is made of the same material as the second bellows pipe used in the first embodiment.

When this trichlorosilane production apparatus was operated in the same manner as in Example 1, the apparatus was disassembled and the connecting cylinder, the extraction pipe, and the plate member were observed, and the extraction pipe was distorted at the portion joined to the plate member. Was recognized.

Comparative Example 3
A trichlorosilane production apparatus was prepared in the same manner as in Example 1 except that a cylindrical member (thickness: 2 mm) having no first bellows pipe was disposed instead of the connecting cylinder. This cylindrical member consists of the same material as the 1st and 2nd cylindrical member of the connection cylinder used in Example 1. FIG.

When this trichlorosilane production apparatus was operated in the same manner as in Example 1, the apparatus was disassembled, and the cylindrical member, the extraction tube, and the second bellows tube were observed. As a result, distortion was observed in the cylindrical member.

<Experimental considerations>
As is clear from the above comparative experiment, the connecting cylinder connecting the reaction furnace and the quenching tower includes the first bellows pipe, and the reaction furnace and the quenching tower are arranged between the extraction pipe and the connecting cylinder. By adopting a configuration that is blocked by the second bellows pipe, it was possible to prevent distortion and breakage of these members due to thermal expansion, and to improve the stability and safety of the apparatus. Moreover, by arranging the second bellows pipe so as to cover the extraction pipe inside the connecting cylinder, the thermal load applied to the extraction pipe can be dispersed, and a large stress is prevented from being locally generated in the extraction pipe. I was able to.

In the above, this invention was demonstrated based on the Example. It is to be understood by those skilled in the art that this embodiment is merely an example, and that various modifications are possible and that such modifications are within the scope of the present invention.

Claims

Reaction comprising: a reaction vessel that generates a reaction product gas containing trichlorosilane and hydrogen chloride from a raw material gas containing tetrachlorosilane and hydrogen; a heater that heats the reaction vessel; and a reaction vessel and an outer cylinder that houses the heater A furnace,
A quenching tower for cooling the reaction product gas;
A connecting cylinder having a first bellows pipe that connects the reaction furnace and the quenching tower in an extendable manner;
An extraction pipe arranged from the reaction vessel to the quenching tower through the inside of the connecting cylinder, and leading the reaction product gas from the reaction furnace to the quenching tower;
Trichlorosilane manufacturing provided with a second bellows pipe arranged substantially coaxially so as to cover the extraction pipe inside the connection cylinder, one end joined to the inner periphery of the connection cylinder and the other end joined to the outer periphery of the extraction pipe apparatus.
The connecting cylinder
A first tubular member having a joint means connected to the reaction furnace at one end and an accommodating portion having an enlarged diameter at the other end;
A second cylindrical member having an insertion side end inserted into the accommodating portion side of the first cylindrical member at one end and joint means connected to the quenching tower at the other end;
The first bellows tube, which is housed in the housing portion, has one end fixed to the housing portion side end portion of the first cylindrical member, and the other end fixed to the insertion side end portion of the second tubular member. Trichlorosilane production equipment.
The trichlorosilane production apparatus according to claim 1, wherein the displacement of the first bellows pipe in the direction perpendicular to the axis is 3 to 10% of the inlet diameter, and the displacement in the axial direction is 2 to 5% of the total length.
The apparatus for producing trichlorosilane according to claim 1, wherein the displacement of the second bellows pipe in the direction perpendicular to the axis is 3 to 10% of the inlet diameter, and the amount of displacement in the axial direction is 2 to 5% of the total length.