JP6956928B1 - filter - Google Patents

Abstract

Prevents the filter element from cracking. The filter (10) has a filter element (40) in which a filter surface (43) extends between a first end (41) and a second end (42), and a first opening is formed in the filter element (40). A partition plate (30) fixed to the inner wall of the flow path forming a space for accommodating the filter element (40) and a second opening into which the filter element (40) is inserted are formed, and the first end (41) and the second end (41) and the second are formed. A jig (50) arranged between the end (42) and the jig (50) is provided.

Description

The present invention relates to a filter.

Conventionally, a filter provided in a flow path through which a gas containing the powder flows is known in order to separate the gas and the powder. For example, Patent Document 1 discloses a gas filtration device including a face plate on which a through hole is formed and a filter element arranged in the through hole while filtering the gas.

Chinese Patent Application Publication No. 102814084

However, the gas filtration device disclosed in Patent Document 1 has a problem that the filter element may be cracked due to vibration of the filter element. One aspect of the present invention is to prevent the filter element from cracking.

In order to solve the above-mentioned problems, the filter according to one aspect of the present invention is a filter provided in a flow path through which a gas containing the powder flows in order to separate the gas and the powder, and is a gas. And the powder are separated, and a filter element in which the filter surface extends between the first end and the second end opposite to the first end and the first opening are formed, and the first opening is formed. The first end or the vicinity of the first end is fixed to the opening, and the fixing portion fixed to the inner wall of the flow path forming a space for accommodating the filter element and the filter element are inserted. A second opening is formed, and a jig is provided between the first end and the second end.

According to one aspect of the present invention, it is possible to prevent the filter element from cracking.

It is a schematic diagram which shows an example of the structure of the filter which concerns on Embodiment 1 of this invention. FIG. 5 is a schematic view showing a state in which the filter element is not fixed to the partition plate and a state in which the housing is divided with respect to the filter shown in FIG. 1. It is a schematic diagram which shows an example of the structure of the jig provided in the filter shown in FIG. It is a schematic diagram which shows an example of the structure of the manufacturing apparatus which includes the filter shown in FIG. It is a schematic diagram which shows an example of the structure of the manufacturing apparatus which concerns on Embodiment 2 of this invention.

[Embodiment 1]
(Structure of filter 10)
FIG. 1 is a schematic view showing an example of the configuration of the filter 10 according to the first embodiment of the present invention. FIG. 2 shows a state in which the filter element 40 is not fixed to the partition plate 30 (a state in which the filter element 40 does not exist) and a state in which the housing 20 is divided with respect to the filter 10 shown in FIG. It is a schematic diagram. FIG. 1 shows the configuration of the filter 10 so that the inside of the housing 20 can be seen for convenience of explanation. The same applies to the figure shown by 101 in FIG. The partition plate 30 corresponds to a fixed portion.

The filter 10 is provided in a flow path through which the gas containing the powder flows in order to separate the gas and the powder. Further, the filter 10 is, for example, a filter provided in the production system of _{trichlorosilane (TCS, SiHCl 3).} The trichlorosilane production system refers to the entire production apparatus for producing trichlorosilane, for example, the entire production apparatus 1 or production apparatus 11 described later.

However, the scope of application of the present invention is not limited to the filter provided in the production system of trichlorosilane. The present invention is also applied to a filter provided in an apparatus for producing polycrystalline silicon from _{chlorosilane gas and hydrogen (H 2} ) by a CVD (Chemical Vapor Deposition) method using the Siemens method. The filter separates the silicon powder and hydrogen chloride from the gas containing the silicon powder (Si) and hydrogen chloride (HCl) discharged from the reaction vessel provided in the apparatus.

Since the present invention is applied to the above-mentioned filter, the powder separated from the gas by the filter element 40 described later of the filter 10 is silicon powder, and the gas separated from the gas by the filter element 40. Contains at least one of hydrogen, hydrogen chloride, nitrogen and chlorosilane gas. Examples of the chlorosilane gas include trichlorosilane, tetrachlorosilane (STC, SiCl4) and the like.

According to the above configuration, even when the gas or powder as described above flows through the flow path, the vibration of the filter element 40 can be suppressed by the jig 50 described later. Further, the filter element 40 separates the silicon powder having a heavy specific gravity from the gas and separates the corrosive gas from the silicon powder. Therefore, when a filter element made of a hard and brittle sintered metal is used, a remarkable effect of preventing the filter element from cracking is exhibited as compared with the case where a filter element made of another material is used.

Unless otherwise specified in the present specification, "A to B" representing a numerical range means "A or more (including A and larger than A) and B or less (including B and smaller than B)". Hereinafter, the filter 10 provided in the trichlorosilane production system will be described as an example.

Further, in the present specification, the "silicon powder" is intended to be a solid substance containing a silicon element in a metallic state such as metallurgical silicon, silicon iron or polysilicon, and known substances are used without any limitation. .. Further, these silicon powders may contain impurities such as iron compounds, and the components and contents thereof are not particularly limited.

As shown in FIG. 1, the filter 10 includes a housing 20, a partition plate 30 (fixed portion), a filter element 40, and a jig 50. As shown in FIG. 102 in FIG. 2, the housing 20 has an upper cap 21 and a lower chamber 22, and can be divided into an upper cap 21 and a lower chamber 22.

The housing 20 is formed with an inflow port 60, a gas discharge port 70, and a powder discharge port 80. The inflow port 60 is formed so that a gas containing silicon powder flows into the inside of the housing 20. The gas discharge port 70 is formed to discharge the gas separated from the silicon powder from the housing 20. The powder discharge port 80 is formed to discharge the silicon powder separated from the gas from the housing 20.

Further, inside the housing 20, a differential pressure gauge 90 for measuring the differential pressure between the pressure in the first region R1 and the pressure in the second region R2 is installed with respect to the housing 20. The differential pressure between the pressure in the first region R1 and the pressure in the second region R2 is, for example, 100 to 1500 kPaG. The gas containing the silicon powder flows into the housing 20 from the inflow port 60, passes through the second region R2, the filter element 40, and the first region R1 in this order, and passes from the gas discharge port 70 to the housing 20. It is discharged to the outside. The particle size of the silicon powder contained in the gas flowing into the housing 20 is, for example, 1 to 40 μm, and the powder density in the gas is 1 to 5 kg / Nm ³ . The powder concentration of the silicon powder in the gas is 10 to 20 wt%.

The partition plate 30 is a plate that partitions the space inside the housing 20 into a first region R1 and a second region R2. The first region R1 is a region in which the gas separated from the silicon powder by the filter element 40 mainly exists. The second region R2 is a region in which the silicon powder separated from the gas by the filter element 40 and the gas flowing into the housing 20 exist.

By partitioning the space inside the housing 20 into the first region R1 and the second region R2 by the partition plate 30, the gas containing silicon powder that flows into the housing 20 invades the first region R1. It can be prevented from doing so. The partition plate 30 is fixed to the inner wall of the flow path forming the space in which the filter element 40 is housed. Specifically, the partition plate 30 is fixed to the inner wall 23 of the housing 20 to form a fixed portion.

The partition plate 30 is sandwiched between the upper cap 21 and the lower chamber 22 and is fixed to the inner wall 23 of the housing 20 to form a fixed portion. In addition, a holding portion (not shown) capable of holding the partition plate 30 is provided on the upper inner wall portion of the lower chamber 22, and the partition plate 30 is placed on the holding portion so that the partition plate 30 can be placed on the inner wall 23 of the housing 20. It can also be fixed to. In this case, it is necessary to have a structure so that no gap is formed between the holding portion and the partition plate 30.

As shown in FIG. 101 in FIG. 2, the partition plate 30 is formed with the first opening 31. The vicinity of the first end 41 or the first end 41 of the filter element 40 is fixed to the first opening 31. The first opening 31 is formed in the partition plate 30 because the gas that has passed through the filter element 40 is introduced into the first region R1. No opening is formed in the partition plate 30 other than the first opening 31.

The vicinity of the first end 41 is, for example, a length of about 10% of the length L1 of the filter element 40 along the first end 41 and the stretching direction D1 described later from the first end 41 of the filter element 40. Only the following is the part between the position facing the powder discharge port 80 and the position. That is, if the length L1 is 1000 to 1500 mm, the position of the filter element 40 at the first end 41 and 100 to 150 mm from the first end 41 along the stretching direction D1 toward the powder discharge port 80. Is the part between.

In consideration of filtration efficiency, it is preferable that the upper end of the first end 41 and the upper surface of the partition plate 30 are in the same plane. That is, it is preferable that the first end 41 and the partition plate 30 are joined. By fixing at least the vicinity of the first end 41 to the first opening 31, the filter element 40 is sufficiently extended toward the second region R2 with respect to the partition plate 30, so that the filtering function of the filter element 40 is sufficient. Can be demonstrated.

The filter element 40 separates the gas and the silicon powder as powder, and the filter surface 43 forms between the first end 41 and the second end 42 opposite to the first end 41. It is a filter medium to be stretched. The filter element 40 is preferably a sintered metal. Thereby, the filter 10 having sufficient corrosion resistance and wear resistance can be realized. Examples of the sintered metal include incoloy, inconel, and hastelloy, which are sintered metals containing 1 wt% or more, preferably 2 to 20 wt%, and more preferably 5 to 20 wt% of molybdenum having high corrosion resistance.

The gas inflow amount (linear velocity) per surface area of the filter element 40 is, for example, 20 to 60 ^{m 3} / m ² / hr. The filtration accuracy of the filter element 40 is, for example, preferably 5 μm, more preferably 2 μm. The filtration accuracy means that 99.9% or more of the powder having a numerical particle size (for example, a particle size of 5 μm or a particle size of 2 μm) indicating the filtration accuracy can be removed.

The length L1 of the filter element 40 along the stretching direction D1 is, for example, 1000 to 1500 mm. The stretching direction D1 is the same as the stretching direction of the housing 20. The diameter of the filter element 40 is 40 to 60 mm.

The number of filter elements 40 housed inside the housing 20 is, for example, 50 to 250 per filter 10. When the manufacturing apparatus 1 described later is manufacturing trichlorosilane and a gas containing silicon powder is circulating inside the housing 20, the temperature of the filter element 40 is, for example, 100 to 300 ° C.

The jig 50 is arranged between the first end 41 and the second end 42 of the filter element 40. As shown in FIG. 101 in FIG. 2, the jig 50 is formed with a second opening 51. The filter element 40 is inserted into the second opening 51. Further, the position of the first opening 31 of the partition plate 30 and the position of the second opening 51 formed in the jig 50 coincide with each other when viewed from the direction from the gas discharge port 70 to the powder discharge port 80.

According to the above configuration, the vibration of the filter element 40 is suppressed by the structure in which the filter element 40 is inserted into the second opening 51. Therefore, the moment of the force applied to the second end 42 of the filter element 40 due to the vibration of the filter element 40 can be reduced as compared with the case where the jig 50 is not arranged. Therefore, it is possible to prevent the filter element 40 from cracking.

Since it is possible to prevent the filter element 40 from cracking, it is possible to prevent the silicon powder from accumulating in a process downstream of the filter 10 and causing a problem due to the passage of the silicon powder from the cracked portion of the filter element. Can be done. Further, when the length of the filter element is longer than a predetermined length, the probability that the filter element is cracked increases. Therefore, by providing the jig 50, the filter element 40 can be lengthened to efficiently separate the gas and the silicon powder and prevent the filter element 40 from cracking.

Further, when the filter 10 is backwashed, a high pressure gas is circulated from the downstream side of the filter 10. Even in such a case, the vibration of the filter element 40 due to the high pressure gas can be suppressed.

The jig 50 is arranged at a position separated from the partition plate 30 by a distance DS along the stretching direction D1 of the filter element 40. The distance DS is the same as the length of 1/3 or more and 2/3 or less of the length L1 along the stretching direction D1 in the filter element 40. According to the above configuration, since the jig 50 is arranged near the center of the filter element 40, the vibration of the filter element 40 can be efficiently suppressed.

The jig 50 is fixed to the partition plate 30 via a connecting member 32 that connects the jig 50 and the partition plate 30. According to the above configuration, since the jig 50 and the partition plate 30 can be taken out from the housing 20 together, the inside of the housing 20 can be easily cleaned. Further, since the housing 20 can be divided into an upper cap 21 and a lower chamber 22, the jig 50 and the partition plate 30 can be easily taken out from the housing 20 together. Further, the vibration preventing material P1 described later can be easily inserted between the second opening 51 and the filter element 40.

The configuration in which the jig 50 is fixed to the partition plate 30 via the connecting member 32 is an example, and the configuration in which the jig 50 is fixed to the housing 20 is not limited. For example, the jig 50 may be fixed to the inner wall of the lower chamber 22.

The material of the jig 50 is preferably stainless steel, for example, SUS304. Further, the thickness of the jig 50 along the stretching direction D1 is preferably, for example, about 5 to 20 mm, and preferably about 10 mm.

The outer diameter of the jig 50 is smaller than the inner diameter of the housing 20, that is, the inner diameter of the lower chamber 22. Therefore, when the jig 50 is arranged along the plane orthogonal to the stretching direction D1, the jig 50 does not come into contact with the inner wall of the housing 20. The inner diameter of the housing 20 is the diameter of the cross section of the housing 20 orthogonal to the stretching direction D1.

The shape of the opening of the second opening 51 formed in the jig 50 is not particularly limited, and may be any shape as long as the filter element 40 can be inserted. In this case, it is preferable that the vibration preventing material P1 described later is interposed between the second opening 51 and the filter element 40.

Consider the case of a filter 10 including a plurality of filter elements 40. In this case, considering the workability of forming the filter 10 itself, the shape of the opening of the second opening 51 is the cross section of the filter element 40 (when the filter element 40 is inserted into the second opening 51, the second opening is the second opening. It is preferable that the shape is the same as the shape of the filter element 40 (cross section of the filter element 40 existing on the same plane as 51). For example, if the filter element 40 is cylindrical, the opening shape of the second opening 51 is preferably circular.

When the anti-vibration material P1 is not used, the size of the opening of the second opening 51 may be such that the anti-vibration effect of the filter element 40 is not reduced. However, considering the preparation of the filter 10 itself and the vibration prevention effect of the filter element 40, the following is preferable.

First, as described above, it is preferable that the cross-sectional shape of the filter element 40 and the shape of the opening of the second opening 51 are the same and have a similar relationship with each other. Although it affects the scale of the filter 10, it is as follows in consideration of the ease of preparation of the filter 10 itself. Specifically, as shown in FIG. 3, when the length from the center point of the cross-sectional shape of the filter element 40 to the outer peripheral edge thereof is La, from the center point of the opening of the second opening 51 to the inner peripheral edge thereof. The length of is preferably La or more and 1.80 La or less.

However, if the size of the opening of the second opening 51 becomes too large, the effect of suppressing the vibration of the filter element 40 tends to decrease, and it is necessary to use a plurality of vibration prevention materials P1 and a large amount. Therefore, workability tends to decrease. Further, if the size of the opening of the second opening 51 becomes too small, precise control is required when inserting the filter element 40, and in this case as well, workability tends to decrease when the filter 10 itself is configured. It is in.

Therefore, the length from the center point of the opening of the second opening 51 to the inner peripheral edge thereof is more preferably more than La and 1.70 La or less, and further preferably 1.02 La or more and 1.60 La or less. It is preferable, and it is particularly preferable that it is 1.05 La or more and 1.50 La or less.

When the length from the center point of the opening of the second opening 51 to the inner peripheral edge thereof becomes too large with respect to La, it is preferable to use the vibration preventing material P1 as necessary. For example, the size of the opening of the second opening 51 varies depending on the scale of the filter. Therefore, although it cannot be unconditionally limited, when the length from the center point of the opening of the second opening 51 to the inner peripheral edge thereof is 1.01 La or more, vibration is performed in order to enhance the vibration prevention effect. It is preferable to use the preventive material P1 together.

Specific examples of suitable forms are as follows. In particular, considering the ease of preparation of the filter 10, it is as follows. When the shape of the filter element 40 is cylindrical, as described above, the shape of the opening of the second opening 51 is preferably circular. In this case, the radius of the opening of the second opening 51 (based on the inner peripheral edge) is preferably larger than the radius of the cross section of the filter element 40 (based on the outer peripheral edge) by more than 1 mm and 15 mm or less, preferably 2 mm or more. It is more preferable to make it larger by 10 mm or less. Then, the filter element 40 is inserted into the second opening 51. In this case, it is preferable to interpose the vibration preventing material P1 in the gap formed between the second opening 51 and the filter element 40.

Although not particularly limited, in order to facilitate the preparation of the filter 10 itself and to further enhance the effect of suppressing the vibration of the filter element 40, between the second opening 51 and the filter element 40. It is preferable to interpose the resin anti-vibration material P1.

Examples of the resin used for the anti-vibration material P1 are olefin resins such as polyethylene and polypropylene, and fluorine resins such as polytetrafluoroethylene (Teflon (registered trademark)). Among them, the vibration-preventing material P1 made of a fluororesin is excellent in corrosion resistance and slipperiness with other materials, and therefore can be preferably used. By providing the anti-vibration material P1, the vibration of the filter element 40 can be further suppressed as compared with the case where the anti-vibration material P1 is not provided. Further, since the anti-vibration material P1 is made of resin, it is possible to reduce the corrosion of the anti-vibration material P1 even when the gas flowing through the flow path is an acidic corrosive gas.

Further, the shape of the anti-vibration material P1 is not particularly limited, and by allowing the anti-vibration material P1 to exist in at least a part of the inner peripheral surface of the second opening 51, the second opening 51 and the filter element are present through the anti-vibration material P1. The shape may be such that it comes into contact with 40. Therefore, the vibration preventing material P1 does not have to be present on the entire inner peripheral surface of the second opening 51.

However, for the following reasons, it is preferable that the vibration preventing material P1 is present on the entire inner peripheral surface of the second opening 51. That is, since the vibration preventing material P1 is present on the entire surface of the inner peripheral surface, when the filter 10 is configured, the axis of the stretching direction D1 of the filter element 40 tends to be straight, and cracking of the filter element 40 can be suppressed. ..

In addition, since the anti-vibration material P1 is arranged between the second opening 51 and the entire circumference of the filter element 40, it is possible to efficiently suppress the vibration of the filter element 40. For example, by forming the anti-vibration material P1 into a ring shape, the filter element 40 vibrates, and the portion of the surface of the filter element 40 that may come into contact with the second opening 51 is formed by the anti-vibration material P1. Can be covered.

The anti-vibration material P1 can be arranged as follows. For example, the filter element 40 is inserted into the second opening 51, the jig 50 is installed at a desired position in the stretching direction D1 of the filter element 40, and then the gap between the second opening 51 and the filter element 40 is filled. As described above, the vibration prevention material P1 can be provided.

In this case, the anti-vibration material P1 does not have to be present on the entire inner peripheral surface of the opening of the second opening 51, and at least the filter element 40 and the second opening 51 come into contact with each other via the anti-vibration material P1. It can also be in such a state.

Further, the vibration preventing material P1 may be arranged in advance on the inner peripheral surface of the second opening 51, and the filter element 40 may be inserted into the second opening 51.

As a method having the best operability and arranging the vibration preventing material P1, it is preferable to adopt the following method. First, the second end 42 or the vicinity of the second end 42 of the filter element 40 is inserted into the second opening 51. In this state, the filter element 40 and the second opening 51 are aligned with each other, and the vibration preventing material P1 is arranged between the second opening 51 and the vicinity of the second end 42 or the second end 42.

Then, the jig 50 is arranged at a predetermined position in the stretching direction D1 of the filter element 40. As a result, the filter 10 can be efficiently prepared even when a plurality of filter elements 40 are present. When this method is adopted, the operability can be improved in the preparation of the filter 10 because the connecting member 32 connects the partition plate (fixing portion) 30 and the jig 50.

In the method of arranging the vibration preventing material P1 in advance on the inner peripheral surface of the second opening 51 and the method of aligning the second opening 51 with the second end 42 and the like, the position (height) of the jig 50 is used. Will be adjusted to the specified position later. Therefore, strictly speaking, a gap is formed between the vibration preventing material P1 and the filter element 40.

For example, when the position of the jig 50 is adjusted, the vibration preventing material P1 moves on the filter element 40. Therefore, in this case, strictly speaking, there is a gap between the filter element 40 and the vibration preventing material P1. However, the gaps may be such that the anti-vibration effect is not reduced and the filterability is not adversely affected. Specifically, the gap is preferably 1 mm or less, more preferably 0.5 mm or less, further preferably about 0.2 mm or less, and 0.1 mm or less. It is particularly preferable that the gap is about the same.

The lower limit of the gap is a value exceeding 0 mm in consideration of interposing the vibration preventing material P1 in the gap after aligning the jig 50. In this case, the anti-vibration material P1 is preferably made of a fluororesin because it is desirable that the anti-vibration material P1 has good slipperiness with respect to the filter element 40.

FIG. 3 shows an aspect in the case where the vibration preventing material P1 is provided. FIG. 3 shows a configuration in which the ring-shaped anti-vibration material P1 is arranged on the inner peripheral surface of the second opening 51, that is, at a position where the filter element 40 vibrates and comes into contact with the second opening 51.

Further, as shown in FIG. 3, the jig 50 is formed separately from the second opening 51 and also has a third opening 52 for passing gas. FIG. 3 is a schematic view showing an example of the configuration of the jig 50 included in the filter 10 shown in FIG. Since the filter element 40 is not inserted into the third opening 52, the third opening 52 is in a state where gas can pass through. According to the configuration in which the third opening 52 is formed in the jig 50, the air permeability is improved in the vicinity of the filter element 40 as compared with the case where the third opening 52 is not formed due to the passage of gas from the third opening 52. Can be made to. Therefore, the amount of gas passing through the filter 10 can be increased.

Further, the jig 50 may be formed separately from the second opening 51 and the third opening 52, and may be further formed with a fourth opening 53 for passing a gas. The diameter of the fourth opening 53 is smaller than the diameter of the third opening 52. By further forming the fourth opening 53 in the jig 50, the air permeability can be further improved in the vicinity of the filter element 40.

The porosity of the jig 50 is preferably as follows. When the jig 50 is viewed from above or below as shown in FIG. 3, it is relative to the area of the jig 50 (the area when the second opening 51, the third opening 52, and the fourth opening 53 are not opened). The larger the ratio of the total area of the second opening 51, the third opening 52, and the fourth opening 53 (hereinafter, may be referred to as the first porosity), the easier it is for gas to pass through, and the efficiency of filtration is improved. Can be enhanced. However, as the first porosity increases, the strength of the jig 50 itself and the effect of suppressing the vibration of the filter element 40 tend to decrease. Therefore, the first porosity is preferably 50 to 95%, more preferably 70 to 90%.

The filter element 40 is inserted into the second opening 51. At this time, it is the ratio of the total area of the third opening 52 and the fourth opening 53 to the area of the jig 50 (the area when the second opening 51, the third opening 52, and the fourth opening 53 are not opened). The second porosity is preferably 10 to 50%, more preferably 20 to 40%.

Consider a case where the vibration preventing material P1 does not exist and a gap is formed between the second opening 51 and the filter element 40. In this case, the second void ratio is the third opening 52 and the fourth opening 53 with respect to the area of the jig 50 (the area when the second opening 51, the third opening 52, and the fourth opening 53 are not opened). And the ratio of the total area of the gap.

The filter 10 may include a plurality of jigs 50. In this case, the plurality of jigs 50 are connected to each other via the connecting member 32, respectively. The plurality of jigs 50 are fixed to the partition plate 30 via the connecting member 32. The plurality of jigs 50 are arranged between the first end 41 and the second end 42 of the filter element 40.

(Method of forming an opening for a jig)
First, as shown in FIG. 101 in FIG. 2, consider a state in which the partition plate 30 is fixed to the housing 20 and the jig 50 is housed inside the housing 20. In this state, the position of the first opening 31 of the partition plate 30 and the position of the second opening 51 formed in the jig 50 match when viewed from the direction from the gas discharge port 70 to the powder discharge port 80. In consideration of this, the second opening 51 is formed in the jig.

After forming the second opening 51 in the jig, the third opening 52 is formed in the portion of the jig where the second opening 51 is not formed. Further, the fourth opening 53 is formed in the portion of the jig where the second opening 51 and the third opening 52 are not formed. By forming the second opening 51, the third opening 52, and the fourth opening 53 in the jig in this way, the jig 50 is completed.

(Structure of manufacturing apparatus 1)
FIG. 4 is a schematic view showing an example of the configuration of the manufacturing apparatus 1 including the filter 10 shown in FIG. The manufacturing apparatus 1 is an apparatus for producing trichlorosilane using silicon powder. As shown in FIG. 4, the manufacturing apparatus 1 includes a first reaction vessel 2, a cooler 3, a first storage tank 4, and a filter 10. These components included in the manufacturing apparatus 1 are connected to each other by piping.

The first reaction vessel 2 is provided in the production system for trichlorosilane, and also contains silicon powder and hydrogen chloride supplied from the outside, and reacts the silicon powder with hydrogen chloride to cause trichlorosilane, tetrachlorosilane, and hydrogen. To generate. The reaction formula is as follows. Silicon powder (Si) + 3HCl → SiHCl ₃ + H ₂
Silicon powder (Si) +4 HCl → SiCl ₄ + 2H ₂
The cooler 3 cools the silicon powder, hydrogen, trichlorosilane, tetrachlorosilane, etc. supplied from the first reaction vessel 2. The first storage tank 4 stores the silicon powder discharged from the lower part of the first reaction vessel 2 and the silicon powder discharged from the powder discharge port 80 of the filter 10.

The filter 10 takes in silicon powder, hydrogen, trichlorosilane, tetrachlorosilane, etc. that have passed through the cooler 3 from the inflow port 60. The filter 10 removes the silicon powder from the silicon powder, hydrogen, trichlorosilane, tetrachlorosilane, etc. that have passed through the cooler 3. That is, the gas and powder separated by the filter element 40 of the filter 10 are discharged from the first reaction vessel 2. When the filter 10 does not include the housing 20, the filter 10 may be provided in the pipes connected to the front and rear of the cooler 3.

[Embodiment 2]
FIG. 5 is a schematic view showing an example of the configuration of the manufacturing apparatus 11 according to the second embodiment of the present invention. For convenience of explanation, the members having the same functions as the members described in the first embodiment are designated by the same reference numerals, and the description thereof will not be repeated.

As shown in FIG. 5, the manufacturing apparatus 11 includes a second reaction vessel 12, a heat exchanger 13, a heater 14, a second storage tank 15, and a filter 10A. These components included in the manufacturing apparatus 11 are connected to each other by piping. As the filter 10A, the same filter 10A may be used.

Hydrogen and tetrachlorosilane are supplied to the heat exchanger 13. This tetrachlorosilane was produced as a side reaction by, for example, the first reaction vessel 2 described above. The heat exchanger 13 heat exchanges silicon powder, hydrogen, and trichlorosilane via the second reaction vessel 12 with hydrogen and tetrachlorosilane. The heat exchanger 13 supplies hydrogen and tetrachlorosilane to the heater 14. The heater 14 heats tetrachlorosilane and hydrogen to supply tetrachlorosilane and hydrogen to the second reaction vessel 12.

The second reaction vessel 12 contains tetrachlorosilane, hydrogen, and silicon powder supplied from the outside. The second reaction vessel 12 is provided in the trichlorosilane production system, and trichlorosilane is produced by reacting tetrachlorosilane with hydrogen and silicon powder. The reaction formula is as follows.
Silicon powder (Si) + 3SiCl ₄ + 2H ₂ → 4SiHCl ₃
The second reaction vessel 12 supplies silicon powder, hydrogen, trichlorosilane, and unreacted tetrachlorosilane to the filter 10A via the heat exchanger 13. The second storage tank 15 stores the silicon powder discharged from the lower part of the second reaction vessel 12 and the silicon powder discharged from the powder discharge port 80 of the filter 10A.

The filter 10A takes in silicon powder, hydrogen, trichlorosilane and unreacted tetrachlorosilane supplied from the second reaction vessel 12 via the heat exchanger 13 from the inflow port 60. The filter 10A removes the silicon powder from the silicon powder, hydrogen, trichlorosilane and unreacted tetrachlorosilane. That is, the gas and powder separated by the filter element 40 of the filter 10A are discharged from the second reaction vessel 12.

From the configurations of the first and second embodiments, the filters 10 and 10A can be suitably used for separating the gas and powder discharged from each of the first reaction vessel 2 and the second reaction vessel 12 as described above. can. In particular, when filters 10 and 10A are used for producing trichlorosilane, a filter element made of a sintered metal containing 1 wt% or more of molybdenum having high corrosion resistance can be obtained in order to obtain high-purity trichlorosilane (International Publication No. 2019 / It is preferable to use 098345).

Specifically, examples of the sintered metal include incoloy, inconel, hastelloy, and the like, which are sintered metals containing molybdenum in an amount of preferably 2 to 20 wt%, more preferably 5 to 20 wt%. However, this filter element tends to be brittle. According to the above configuration, even when such a filter element is used, a remarkable effect of preventing the filter element from cracking can be obtained.

Although the description of the first and second embodiments does not describe nitrogen as an inert gas, in any of the embodiments, nitrogen, which is an inert gas, may be used after the reaction is completed. be. For example, the supply of the raw material gas (for example, the gas containing the raw material gas such as HCl, tetrachlorosilane and / or hydrogen) is stopped, the supply is switched to the nitrogen supply, and the atmosphere in the manufacturing apparatus is replaced with nitrogen. In some cases. In this operation, a filter is used to separate the silicon powder in the mixed gas of the raw material gas containing the silicon powder and nitrogen, or in the nitrogen containing the silicon powder. Therefore, the gas separated by the filters 10 and 10A may contain nitrogen.

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present invention.

〔summary〕
The filter according to one aspect of the present invention is a filter provided in a flow path through which a gas containing the powder flows in order to separate the gas and the powder, and separates the gas and the powder and at the same time. A filter element having a filter surface extending between the first end and the second end opposite to the first end and a first opening are formed, and the first end or the said first opening is formed in the first opening. The vicinity of the first end is fixed, a fixing portion fixed to the inner wall of the flow path forming a space for accommodating the filter element, and a second opening into which the filter element is inserted are formed. A jig arranged between the first end and the second end is provided.

According to the above configuration, the vibration of the filter element is suppressed by the structure in which the filter element is inserted into the second opening. Therefore, the moment of the force applied to the second end of the filter element due to the vibration of the filter element can be reduced as compared with the case where the jig is not arranged. Therefore, it is possible to prevent the filter element from cracking.

The jig is arranged at a position away from the fixing portion by a distance along the stretching direction, which is the same as a length of 1/3 or more and 2/3 or less of the length of the filter element along the stretching direction. You may. According to the above configuration, since the jig is arranged near the center of the filter element, the vibration of the filter element can be efficiently suppressed.

A resin anti-vibration material may be interposed between the second opening and the filter element. According to the above configuration, the vibration of the filter element can be further suppressed as compared with the case where the vibration inhibitor is not provided. Further, since the anti-vibration material is made of resin, it is possible to reduce the corrosion of the anti-vibration material even when the gas flowing through the flow path is an acidic corrosive gas.

The jig may be fixed to the fixing portion via a connecting member that connects the jig and the fixing portion. According to the above configuration, since the jig and the fixing portion can be taken out from the flow path collectively, the inside of the flow path can be easily cleaned.

The filter element may be a sintered metal. According to the above configuration, it is possible to realize a filter having sufficient corrosion resistance and wear resistance.

The powder separated from the gas by the filter element is silicon powder, and the gas separated from the powder by the filter element may contain at least one of hydrogen, hydrogen chloride, nitrogen and chlorosilane gas.

According to the above configuration, the vibration of the filter element can be suppressed by the jig even when the gas or powder as described above flows through the flow path. Further, the filter element separates the silicon powder having a heavy specific density from the gas and the corrosive gas from the silicon powder. Therefore, when a filter element made of a hard and brittle sintered metal is used, a remarkable effect of preventing the filter element from cracking is exhibited as compared with the case where a filter element made of another material is used.

The gas and powder separated by the filter element are provided in the trichlorosilane production system, and are discharged from the first reaction vessel that produces the trichlorosilane by reacting the silicon powder with hydrogen chloride. , It may be provided in the production system of the trichlorosilane, and may be discharged from the second reaction vessel that produces the trichlorosilane by reacting tetrachlorosilane with hydrogen and silicon powder.

According to the above configuration, a filter can be suitably used for separating the gas and powder discharged from each of the first reaction vessel and the second reaction vessel as described above. In particular, when a filter is used for producing trichlorosilane, a filter element made of a sintered metal containing 1 wt% or more of molybdenum having high corrosion resistance can be obtained in order to obtain high-purity trichlorosilane (International Publication No. 2019/098345). It is preferable to use. However, this filter element tends to be brittle. According to the above configuration, even when such a filter element is used, a remarkable effect of preventing the filter element from cracking can be obtained.

The jig may be formed separately from the second opening and may be formed with a third opening for passing a gas. According to the above configuration, by passing the gas through the third opening, the air permeability can be improved in the vicinity of the filter element as compared with the case where the third opening is not formed.

(Example)
Hereinafter, the filter of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to this Example. Filters and manufacturing equipment as shown in FIGS. 1 and 4 were used. The filter 10 used is as follows.

<Jig 50>
As the jig 50, a jig 50 having a third opening 52 and a fourth opening 53 formed was used as shown in FIG. The jig 50 was provided with a third opening 52 and a fourth opening 53 so that the second porosity of the jig 50 was 28%.

<Preparation of filter 10>
A partition plate 30 (fixed portion 30) made of Inconel 625 (containing 1 wt% or more of molybdenum) and having 150 filter elements 40 having a length of 1200 mm, a diameter of 50 mm, and a filtration accuracy of 2 μm was used. In a state where the vibration prevention material P1 made of a ring-shaped fluororesin is arranged on the inner peripheral surface of the second opening 51, the partition plate 30 and the jig 50 are combined, and the partition plate 30 and the jig 50 are formed by the connecting member 32. Was connected. At this time, the jig 50 was arranged so as to be 600 mm above the second end 42 of the filter element 40. That is, the jig 50 is arranged at a position having a length of 1/2 of the length along the stretching direction D1 of the filter element 40.

<Separation test between solid and gas>
The following processing was performed using the filter 10. For a gas containing silicon powder (average particle size of about 10 μm), hydrogen chloride, hydrogen, trichlorosilane, and tetrachlorosilane (gas containing 15 wt% of powder), the amount of gas inflow per surface area of the filter element 40 (gas inflow). The linear velocity) was set to 40 m ³ / m ² / hr. The temperature of the filter element 40 was controlled at 200 ° C. and the filter element 40 was operated for one year. After that, the manufacturing apparatus was disassembled and the filter element 40 was confirmed, but the cracked filter element 40 did not exist.

(Comparison example)
In the "preparation of the filter" of the above embodiment, the same method as that of the above embodiment (similar) except that the partition plate 30 to which 150 filter elements 40 are fixed is used without using the jig 50. The test was carried out in "Separation test of solid and gas"). After 3 months of operation, the indicated value of the differential pressure of the differential pressure gauge 90 of the filter decreased, so the operation was stopped and the filter was inspected to be open. As a result, 18 filter elements 40 were cracked in the vicinity of the first opening 31.

The present invention can be used for separating gas and powder.

1, 11 Manufacturing equipment 2 1st reaction vessel 10, 10A filter 12 2nd reaction vessel 20 Housing 23 Inner wall 31 1st opening 32 Connecting member 40 Filter element 43 Filter surface 50 Jig 51 2nd opening 52 3rd opening D1 Stretching Direction P1 Anti-vibration material

Claims (5)

A filter provided in a flow path through which a gas containing the powder flows in order to separate the gas and the powder.
A filter element that separates gas and powder and has a filter surface extending between the first end and the second end opposite to the first end.
A first opening is formed, and the first end or the vicinity of the first end is fixed to the first opening, and is fixed to the inner wall of the flow path forming a space for accommodating the filter element. Department and
A filter comprising a second opening into which the filter element is inserted and a jig arranged between the first end and the second end.
The jig is arranged only at a position away from the fixing portion by a distance along the stretching direction, which is the same as a length of 1/3 or more and 2/3 or less of the length of the filter element along the stretching direction. Being done
The powder separated from the gas by the filter element is a silicon powder.
The gas that is separated from the powder by the filter element, hydrogen state, and are those containing at least one of hydrogen chloride, nitrogen and chlorosilane gas,
The jig is formed separately from the second opening and also has a third opening and a fourth opening for passing gas, and the fourth opening is smaller than the third opening.
When the jig is viewed from above or below, the third opening and the fourth opening relative to the area of the jig in which the second opening, the third opening, and the fourth opening are not opened. filter porosity as the area ratio of the openings and wherein 10-50% der Rukoto. The filter according to claim 1 , wherein a resin-made anti-vibration material is interposed between the second opening and the filter element. The filter according to claim 1 or 2 , wherein the jig is fixed to the fixing portion via a connecting member that connects the jig and the fixing portion. The filter according to any one of claims 1 to 3 , wherein the filter element is a sintered metal. The gas and powder separated by the filter element are
It is provided in the production system of trichlorosilane, and is discharged from the first reaction vessel that reacts silicon powder with hydrogen chloride to produce the trichlorosilane, or is discharged from the first reaction vessel.
Any of claims 1 to 4 , which is provided in the trichlorosilane production system and is discharged from a second reaction vessel that produces the trichlorosilane by reacting tetrachlorosilane with hydrogen and silicon powder. Or the filter according to item 1.

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