JPH0365212A - Gas separating membrane module - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides efficient extraction of oxygen-enriched gas from a gas mixture whose main components are, for example, oxygen and nitrogen.
Moreover, the present invention relates to a strong flat membrane type gas separation membrane module.

Conventional technology In recent years, oxygen-enriched gas has been widely used for combustion, medical purposes, vegetable gardening, fish farming, etc., and oxygen cylinders using cryogenic separation are the most common method for obtaining these gases. ,
Other typical methods include methods that utilize gas adsorption and desorption on solid surfaces (zeolites, etc.), and gas separation membranes that use organic membranes to easily create enriched gases. It is being said. As a conventional separation technique using a polymer membrane, there is a gas permeable membrane module as shown in Japanese Patent Application No. 181480/1983, for example.

A conventional gas separation membrane module, which is one of the gas separation means described above, will be explained below with reference to the drawings.

Fig. 3 is a cross-sectional view of two conventional gas separation membrane modules stacked together, Fig. 4 is a partially exploded perspective view of the center frame and gas outlet area of the conventional gas separation membrane module, and Fig. 5 FIG. 6 is a perspective view of a conventional frame in which a communicating body is fitted, and FIG. 6 is a perspective view of the entire conventional frame.

In Figures 3, 4, 5, and 6, 11° is
Impregnating agent 1 with continuously foamed ether urethane foam
12 is a breathable sheet of polyethylene nonwoven fabric that is entirely bonded to the communication body 11 by integral press molding; 13 is the communication body 11 and the breathable sheet 12 bonded to the communication body 11 by heat curing and press molding; Impregnating agent (methyl diisocyanate) for full-surface adhesion with integral brace mold
It is. 14 is a frame formed by extrusion molding, separate frame molding, injection molding, etc.; 14a is a groove formed inside the frame; 14b is a stepped hole that connects the gas outlet 18 and the groove 14b; 14c 14d is the module pitch when the gas separation membrane module is stacked, and 15 is the middle crosspiece for reinforcing the frame 4. , 15a is
a convex portion for fitting the middle crosspiece j5 into the concave portion of the groove 14a;
16 is a silicon-based gas separation membrane that selectively separates a mixed gas; 17 is a double-sided adhesive tape that keeps the gas separation membrane 16 and the frame J4 airtight; for example, Knit 505 (trade name, manufactured by Nitto Electric Industry Co., Ltd.); ), 18 is a gas outlet for taking out oxygen-enriched air. In FIGS. 4 and 5, arrows indicate the flow of oxygen-enriched air when the pressure is reduced by a vacuum pump.

Regarding the gas separation membrane module configured as above,
The operation will be explained below.

First, when vacuum suction is performed from the outside of the gas separation membrane module through the gas outlet 18 using a vacuum pump, the air outside the gas separation membrane module is selectively separated by the gas separation membrane 16, and the gas separation membrane module, -. The oxygen-enriched air enters the interior and flows as shown by the arrows in Figures 4 and 5, and the gas outlet 18
More oxygen-enriched air can be obtained.

Since the surface of the communication body 11 is rough, the breathable sheet 12 protects the gas separation membrane ]-6, and prevents it from getting stuck in the communication body 11 when vacuum suction is applied by a vacuum pump. There is. Furthermore, the frame 14 forming the outer wall is provided with a groove 14a on the inside that contacts the outer periphery of the communicating body 71. Said groove 14a
effectively conveys the degree of vacuum when vacuum suction is performed using a vacuum pump, and guides oxygen-enriched air to the gas outlet 18. Middle rail 15
The inside of the gas separation membrane module is at a vacuum level of -560++
aHg.

This is to prevent the frame 14 from deforming inward when the outside temperature is 60°C. In this case, a convex portion 15a is attached to the middle crosspiece 15 so as not to block the groove 14a, which is a passage for oxygen-enriched air, and to obtain adhesive strength, and the convex portion 15a is fitted into the concave portion of the groove 14a and bonded. At this time, the oxygen-enriched air flows inside the communication body 11, passes through the grooves 14a at both ends of the middle crosspiece 15, and is taken out from the gas outlet 18, as shown in FIG. In this way, the gas separation membrane dimensions are 326wm x 1036mm
By inserting reinforcing inner crosspieces 15 at two places in the longitudinal direction (length 1036+m++) of X17nn, no deformation occurred for 1000 hours at a temperature of 60° C. and a degree of vacuum of −560 mmHH.

Also, as shown in Fig. 4, a stepped hole 14bφ8. Open in+n and φ7 holes, insert the outer diameter φ8 cylinder and inner diameter φγ of the gas outlet 18 and glue them.

This changes the inner diameter of the gas outlet and the stepped hole (φ71m).
m) There are no steps and oxygen-enriched air flows smoothly.

Note that if the thicker part of the stepped frame 14c is made thicker than the spacer part of the frame 14, new air cannot always be supplied to the gas separation membrane module, so the stepped frame 14c cannot be made thicker than 9M. In addition, the inner diameter is φ7mi, and oxygen enriched air 101
/min, the pressure loss is 3 rtrrs
It was Hg and showed the characteristics as shown in the table below.

The characteristics of the gas separation membrane 16 at that time are shown in the table below.

The gas separation membrane 16 is a composite membrane obtained by applying a polydimethylsiloxane-polysulfone-polyhydroxystyrene copolymer to a porous polypropylene film, DURAGUARD 2400 (manufactured by Polyplastics Co., Ltd., trade name), by a water surface development method. .

In addition, the gas separation membrane 16 is adhesively sealed with double-sided adhesive tape 17 to keep the inside of the gas separation membrane module airtight and prevent outside air from entering from outside the gas separation membrane 16 when vacuum suction is performed using a vacuum pump. There is.

Problems to be Solved by the Invention However, in the conventional gas separation membrane module, the frame 14
If only the convex part 15a of the inner crosspiece 15 is fitted into the concave part of the groove 14a, the connecting body 11 will come off when a force is applied to the gas separation membrane 16, so to prevent this, adhesive is used. I needed to.

However, if the middle crosspiece 15 and the frame 14 are glued together, it will be difficult to insert the communicating body 11 into the frame, and if the communicating body 11 is made smaller so that it can be easily inserted into the frame 14, the space between the frame 14 and the communicating body 11 will be reduced. A large space is formed in the gas separation membrane module, and when the pressure inside the gas separation membrane module is reduced, the gas separation membrane 16 falls into the space, resulting in a shortened service life.

Therefore, the accuracy of the position of the middle crosspiece 15 of the frame 14 and the
It is necessary to maintain the accuracy of the outer dimensions of all three pieces to be fitted into the frame 14, which makes processing accuracy difficult and makes it difficult to assemble the module.Furthermore, if the frame before modularization is used alone, the adhesive will come off and the middle crosspiece will come off. It had the problem of being put away.

Means for Solving the Problem In order to solve this problem, the gas separation membrane module of the present invention 4-
In this method, a groove is provided inside the frame that contacts the outer periphery of the communication body, the depth of this groove is made wider, and the groove on the surface that contacts the communication body is made smaller, and a middle crosspiece is formed without blocking this groove. , has a configuration in which a convex portion is provided at both ends of the middle crosspiece, and the tip of the convex portion is enlarged so that it can be hooked into the groove of the frame which is made smaller.

Function: With this configuration, the middle crosspiece can slide along the groove and can be held in both the pulling and pushing directions perpendicular to the sliding direction. You can shorten the bars. As a result, it is only necessary to fit the two communicating bodies and adjust the last communicating body to the final dimensions, so that the dimensional accuracy of the communicating bodies is not so necessary. Moreover, it becomes easier to assemble the gas separation membrane module, and the inner crosspiece will not come off from the frame even if the frame is alone before modularization.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially exploded perspective view of the gas separation membrane module frame and the vicinity of the middle crosspiece in an embodiment of the present invention, and FIG. 2 is a perspective view of the entire frame.

In Figures 1 and 2, 1 is a continuous body made of continuously foamed ether-based urethane foam that is thermally cured with an impregnating agent 3 and press-molded, and 2 is a polyethylene nonwoven fabric that is entirely bonded to the continuous body 1 by press-molding. The air permeable sheet 3 is an impregnating agent (methyl diisocyanate) for bonding the entire surface of the communicating body 1 and the air permeable sheet 2 together by integral press molding. 4 is extrusion molding and pultrusion molding.

A frame formed by injection molding or the like, 4a is a groove formed inside the frame, 4b is a stepped frame, 5 is a middle crosspiece for reinforcing the frame 4, and 5a is the center crosspiece in the recess of the groove 4a. 6 is a silicon-based gas separation membrane that selectively separates a mixed gas; 7 is the gas separation membrane 6 and the frame 4;
A double-sided adhesive tape, such as Knit 505 (trade name, manufactured by Nitto Electric Kogyo ■), is used to keep the airtight airtight, and 8 is a gas outlet for taking out the oxygen-enriched air. In FIGS. 1 and 2, arrows indicate the flow of oxygen-enriched air when the pressure is reduced by a vacuum pump.

Regarding the gas separation membrane module configured as above,
The operation will be explained below.

First, when vacuum suction is performed from the outside of the gas separation membrane module through the gas outlet 8 using a vacuum pump, the air outside the gas separation membrane module is selectively separated by the gas separation membrane 6 and enters the inside of the gas separation membrane module. The oxygen-enriched air flows as shown by the arrow in FIG. 1, and is obtained from the gas outlet 8.

The air permeable sheet 2 has a rough surface of the communicating body 1, so
It protects the gas separation membrane 6 and prevents it from penetrating the communicating body 1 when the pressure is reduced by a vacuum pump.

Furthermore, the frame 4 forming the outer wall has a groove 4a on the inside that contacts the outer periphery of the communication body 1, and the groove on the side in contact with the communication body 1 is narrow and the groove is widened at the back. The groove 4a efficiently transmits the degree of vacuum when vacuum suction is performed using a vacuum pump, and guides the oxygen-enriched air to the gas outlet 18. The middle crosspiece 5 maintains the inside of the gas separation membrane module at a vacuum level of -560 mnHg and an outside temperature of 60°C.
In this case, the frame 4 is prevented from deforming inwardly, and furthermore, it is prevented from deforming outwardly even when the pressure is returned to atmospheric pressure. Moreover, the middle crosspiece 5 can slide along the groove 4a, and the hook part 5a is attached to the hook that can hold force in both the pulling and pushing directions perpendicular to the sliding direction. Therefore, when fitting the communicating body 1 into the frame 4, the middle crosspiece 5
After sliding in the direction of widening, the communication body 1 is fitted, and then the work is performed to narrow the communication body 1 and the frame 4 again so that there is no space between them. Then, once again, when the second middle crosspiece 51 got stuck, the same operation was carried out, and after fitting the third communicating body 1, it was made so that no space was created between the stepped frame 4b and the communicating body 1. The stepped frame 4b is fixed with adhesive. Although this work may cause a difference in the total length of the frame 4 by about 1 to 3 sq. meters, there is no problem.

In this case, the groove 4a, which is the flow rate of oxygen-enriched air, is not blocked. Specifically, the middle crosspiece 5 can be slid along the groove 4a, and the hook is made thin at both ends and thickened at the tip so that it can hold force in both the pulling and pushing directions perpendicular to the sliding direction. is attached.

At this time, the oxygen-enriched air flows inside the communication body 1, passes through the grooves 4a at both ends of the middle crosspiece 5, and is taken out from the gas outlet 8, as shown in FIG. In this way, the gas separation membrane size is 326
Rib x 1036 + nm x 17 mm longitudinal direction (
By inserting reinforcing inner crosspieces 15 at two places in the length 1036 m+a), there was no deformation for 1000 hours at a temperature of 60°C and a degree of vacuum of -560 m1HH. Moreover, since the force can be maintained in the pulling or pushing direction in the direction perpendicular to the sliding direction, the middle crosspiece 5 of the frame 4 before modularization will not come off.

In addition, when oxygen-enriched air flows at 101/min, the groove 4a
The pressure loss of the module as a whole is 3 rtrn Hg at the gas outlet,
It showed the same performance as the conventional model. As reported by Makami Bulletin at that time, it showed the same performance as the conventional model.

The characteristics of the gas separation membrane 6 at that time are shown in the bulletin below. The gas separation membrane 6 is a composite membrane obtained by applying a polydimethylsiloxane-polysulfone-polyhydroxystyrene copolymer to a porous polypropylene film, DURAGUARD 2400 (manufactured by Polyplastics Co., Ltd., trade name), by a water surface development method. In addition, the gas separation membrane 6 is adhesively sealed with double-sided adhesive tape 17 to keep the inside of the gas separation membrane module airtight and prevent outside air from entering from any part other than the gas separation membrane 6 when vacuum suction is performed using a vacuum pump. There is.

As described above, the gas separation membrane module of the present invention has the communication body 1
A groove is formed on the inside of the frame that contacts the outer periphery of the frame. By providing a convex part on both ends and making the tip of the convex part thick so that it can be hooked on the small part of the groove, the middle crosspiece can slide along the groove, and the tension in the direction perpendicular to the sliding direction can be increased. , can be held against both pushing and pushing directions. Also, even if it is only the frame before modularization, the middle crosspiece will not come off. Moreover, since the middle crosspiece can slide, it is easy to insert the communication body and it is easy to modularize.
Its practical effects are significant.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the main parts near the gas separation membrane module frame and the middle crosspiece in an embodiment of the present invention, Fig. 2 is a perspective view of the entire frame of the same embodiment, and Fig. 3 is a conventional gas separation membrane module. 2
FIG. 4 is an exploded perspective view of the main parts near the center frame and gas outlet of a conventional gas separation membrane module. FIG. 5 is a perspective view of a conventional frame with a communicating body fitted into it. The figure is a perspective view of the entire conventional frame. 1...Communication body, 4...Frame, 4a...
...Groove, 5...Middle crosspiece, 5a...Hook part, 6...Gas separation membrane, 8...Gas outlet. Figure 4 Ufu Hill

Claims (1)

[Claims] a gas separation membrane that selectively separates a mixed gas; a plurality of communicating bodies that hold the gas separation membrane from the inside and have air permeability; A frame forming an outer wall having three or more gas outlet ports, and a middle crosspiece reinforcing the frame so as to divide the communication body, the middle crosspiece is formed without blocking the groove,
The groove and the gas outlet for taking out the gas communicate with each other, and
A gas separation membrane module characterized in that a middle crosspiece can slide along a groove and has a hook part that can hold force in a pulling or pushing direction perpendicular to the sliding direction.