JPH0152335B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sealing the ends of a bundle of capillary tubes with a sealing material made of glass, ceramics or a mixture thereof.

For example, when manufacturing a separation membrane device in which a bundle of porous glass tubes is housed in a cylindrical container, a partition wall through which the porous glass tubes penetrate and is embedded along with the gaps between the porous glass tubes is required. Ru. As a means of forming such partition walls, a method is used in which the end of a porous glass tube is placed in a mold together with powder of a sealing material, held at a predetermined sintering temperature for a predetermined time, and then cooled and released from the mold. Since the volume of the sealing material is reduced, a gap remains inside the partition wall, which has the disadvantage that a partition wall that is airtight against the fluid to be treated cannot be obtained.

The present inventors have developed a method that is effective when using glass or ceramic sealing materials, which have low fluidity and whose volume decreases after the sealing process. The present invention was arrived at after conducting extensive research on a method for sealing thin tubes.

That is, the present invention provides a molded container having an open upper surface and an opening that can penetrate the capillary bundle when the ends of a capillary bundle consisting of a large number of capillaries are sealed with a sealing material made of glass, ceramics, or a mixture thereof. using a pressure member that can slide along the wall of the molded container, the thin tube bundle is passed through the opening of the pressure member and placed at a position reaching the bottom of the molded container, and the sealing material is applied. A method for sealing the ends of a thin tube bundle, characterized in that the sealing material is placed around the thin tube bundle and sintered by applying pressure to the sealing material by heating and sliding the pressure member toward the bottom of the molded container. It is something.

Next, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a separation membrane device in which a bundle of thin tubes made up of a large number of thin tubes is housed inside a cylindrical container, and FIG. 2 is a perspective view of an element made of the bundle of thin tubes shown in FIG. 1. Regarding such a separation membrane device, its structure and functions when used for separation operations are described in detail in, for example, Japanese Patent Laid-Open No. 119402/1983.

In FIG. 1, a bundle of thin tubes 4 is housed in a cylindrical container consisting of a cylindrical member 1 and end plates 2 and 3, and the thin tubes forming the bundle of thin tubes 4 penetrate a partition wall 5 and open on the left side. are doing. On the other hand, the other end of the thin tube is embedded in the partition wall 6 to form a closed structure. A porous tube 7 is arranged near the central axis of the bundle 4 of thin tubes, and the thin tubes are stacked around this porous tube 7. The porous tube 7 has an opening in its tube wall, and a fluid flow path 8 within the porous tube communicates with the outside of the porous glass tube through this opening. Further, the partition wall 5 is sandwiched between the cylindrical member 1 and the end plate 2. Here 9, 10, 11 are Patsukin, 12,
13, 14, and 15 are bolt holes. Further, 16 is a raw fluid inlet, and 18 is a permeate fluid outlet. Second
In the figure, thin tubes are arranged approximately parallel to the axis around the porous tube 7 to form a thin tube bundle 4, one end of the thin tube opens through the partition wall 5, and the other end opens into the block 6. It is shown embedded in and closed.

3 and 4 are partial cross-sectional views of partition walls 5 and 6 manufactured by the method of the present invention. FIG. 3 corresponds to the partition wall 6 in FIG. 2, and shows a thin tube 20 embedded in a sealing material 19 and closed at its end. Also, Figure 4 shows the second
Corresponding to the partition wall 5 in the figure, a thin tube 20 is shown penetrating the sealing material 25 and fixed with its end open.

FIGS. 5 and 6 illustrate the method for sealing the ends of a capillary bundle according to the present invention. FIG. 5 shows a molded member consisting of a molded container 31 with an open upper surface and a pressure member 24 having one opening 23 through which the thin tube bundle 22 can pass, and which can slide along the wall of the molded container 21. This shows the case where the ends are sealed. Further, in FIG. 6, two or more openings 23 are used as the pressure member 24.
This shows the case where the ends are sealed using a material having the following properties.
Next, the sealing process will be explained. First, molded container 2
1 through the opening 23 of the pressure member 24 until its end reaches the bottom of the molded container, and the sealing material 25 is filled through the opening 23. Next, after heating to a predetermined temperature, the pressure member 24 is slid toward the bottom of the molded container from the direction of the arrow shown in FIGS. 5 and 6, and the molded container 21 and the pressure member 24 are occupied. Gradually reduce the volume. This pressurizing operation eliminates the gaps in the sealing material 25 and forms a uniform sintered body, and at the same time, the thin tube bundle 2
A sealing material 25 is also filled in the gaps between the thin tubes 2 . After the pressure and heating operation is completed, the pressure member 24 is cooled down and the pressure member 24 is removed, resulting in a thin tube bundle 22 as shown in FIG.
A partition wall through which is penetrated is obtained.

Further, in the practice of the present invention, the sealing operation can be performed by attaching an air-permeable mesh material (for example, a wire mesh) and/or rough cloth made of heat-resistant silica fiber to the lower surface side of the pressure member 24. Such an operation makes it difficult for the sealing material to fall upward, and has the advantage of being able to apply uniform pressure.

Although the present invention has been explained above mainly using a separation membrane device as a specific example, the present invention is not limited to these applications. For example, it can also be applied to the manufacture of tube sheets in shell-and-tube heat exchangers equipped with a large number of thin tubes.

The material of the thin tube in the present invention is an inorganic material such as glass, ceramics, or metal. Although there is no particular restriction on the outer diameter of the capillary, the bonding method of the present invention is most effective when the diameter of the capillary is sufficiently thin, such as 2 mm or less. It is preferable to use porous glass as the capillary in the present invention, and a typical example thereof has a composition of 22-75% by weight of SiO ₂ and 16% by weight of Na ₂ O2.
weight percent, Al ₂ O ₃ 0-5 weight percent,
Examples include high-silicate porous glass whose raw material glass is borosilicate glass containing 0-5 weight percent of ZrO ₂ and 0-5 weight percent of TiO ₂ . This kind of porous glass is made by melting and forming the above raw material glass, and then
It can be produced by performing heat treatment at a temperature of -650°C to cause phase separation, and eluting the resulting sodium borate-rich phase with acid. The resulting porous glass is a high silicate glass containing more than 95 weight percent SiO ₂ .

The adhesive material in the present invention is made of common glass, ceramics, or a mixture thereof. These materials are generally powders at room temperature, and at least a portion of them must melt or have sinterability at the sealing temperature, and there are no particular restrictions on their selection, but preferably Ceramics with a negative coefficient of thermal expansion (e.g. Al ₂ O ₃ , LiO ₂ , SiO ₂
For example, a mixture of β-eucryptite (composed of β-eucryptite) and an inorganic binder (for example, commercially available Pyrex glass) having a softening point of 1000° C. or lower.

Example Composition: 62.5% by weight of SiO ₂ , 27.3% by weight of B ₂ O ₃ , 7.2% by weight of Na 2 _O , 3.0% by weight of Al ₂ O ₃
Weight percent borosilicate glass capillary tubes (outer diameter 2 mm, inner diameter 1 mm) were heat treated at 550 °C to separate the phases, then treated with sulfuric acid at 95 °C to elute some phases, and then heated to 800 °C. A porous glass tube was produced by heat treatment.

On the other hand, the molar ratio of LiO ₂ , Al ₂ O ₃ and SiO ₂ was 1:1:
Ceramics with a negative coefficient of thermal expansion were produced by firing at 1400°C for 5 hours with a composition of 1.5. The linear thermal expansion coefficient of this ceramic was -60×10 ^-7 1/°C on average at 300-600°C. A mixture of this ceramic powder (average particle diameter 60 micrometers) and commercially available Pyrex glass powder (average particle diameter 60 micrometers) at a weight ratio of 4:6 was used as a sealing material.

A molded carbon container having the shape shown in FIG. 5 was prepared. The bundle of 30 porous glass tubes (outer diameter 2 mm) is inserted through the opening of the pressure member until it reaches the bottom of the molded container, and the sealing material is applied through the opening of the molded container. filled inside. Next, this molded container, the ends of the thin tube bundle, and the sealing material were heated to 900° C., held at this temperature for 10 minutes, and then a pressure member was slid from above to below to apply pressure, and then cooled. After cooling, the pressure member was removed, and an airtight partition wall penetrated by a bundle of porous glass tubes as shown in FIG. 7 was obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a separation membrane device in which a bundle of thin tubes is housed inside a cylindrical container, and FIG. 2 is a perspective view thereof. Further, FIGS. 3 and 4 are partial sectional views of the partition wall according to the method of the present invention. Furthermore, Figures 5 and 6
The figures are for explaining the end sealing method of the present invention, and FIG. 7 is a perspective view of a partition wall manufactured by the method of FIGS. 5 and 6. 5, 6; Partition wall, 21; Reaction container, 22; Tube bundle, 23; Opening, 24; Pressure member, 25; Sealing material.

Claims (1)

[Claims] 1. The end of a tubule bundle consisting of a large number of tubules is made of glass,
For sealing with a sealing material made of ceramics or a mixture thereof, a molded container with an open top surface and a pressure member that has an opening that can penetrate the thin tube bundle and can slide along the wall of the molded container. , the thin tube bundle is passed through the opening of the pressure member and placed at a position reaching the bottom of the molded container, and the sealing material is placed around the thin tube bundle, and heated and the molded container of the pressure member is heated. A method for sealing the end of a thin tube bundle, which is characterized by pressurizing the sealing material by sliding it toward the bottom and sintering it. 2 In claim 1, the tube bundle is made of porous glass tubes, and the sealing material is a mixture of ceramics with a negative coefficient of thermal expansion and an inorganic composite with a softening point of 1000°C or less. End sealing method for tube bundles. 3. A method for sealing the ends of a capillary bundle according to claim 1, which uses an air-permeable mesh and/or sackcloth together with a pressure member.