JPS6242736Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention uses a selective gas permeable membrane to concentrate and separate a specific gas from a mixture of two or more gases through the membrane. This provides a modular structure that has a high level of functionality. In particular, the present invention provides a modular structure that is effective when a homogeneous ultra-thin film of 1 μm or less is used as a selective gas permeable membrane.

Various modules having a flat plate-like structure have been proposed in the past, and a typical example is the one described in US Pat. No. 3,332,216 by SAStern.

This is a structure in which the membrane is lined with a fibrous sheet, which is pasted on both sides of a metal wire mesh, and the periphery is sealed, forming a unit that is laminated.

The above structure is sufficiently effective when the permeable membrane has sufficient mechanical strength and thickness, and when the gas to be separated is an inert gas, but when the permeable membrane has a thickness of 1μ or less, In the case of a thin membrane, there is a risk that the membrane may be deformed and damaged due to the pressure difference between the inlet and outlet sides. Furthermore, depending on the properties of the gas to be separated, the internal wire mesh may deteriorate due to corrosion. The present invention improves the above-mentioned drawbacks and provides an excellent selective gas permeable membrane module that does not damage the gas permeable membrane and does not cause corrosion or other deterioration.

An embodiment of the present invention will be described in detail below with reference to the drawings. Figure 1 is an exploded perspective view of a module in an embodiment of the present invention, where 1 is an outer frame, 2 is a plate with a roughened surface, 3 is a breathable sheet, and 4 is a composite membrane with a thickness of 1 μm. A selective gas permeable composite membrane is constructed by integrating a selective gas permeable homogeneous membrane and a porous membrane consisting of the following ultra-thin membranes, and 5 is a gas permeation port to be separated taken out from inside the module.

FIG. 2 shows a cross section of the module, and the composite membrane 4 covers the plate-shaped body 2 with a roughened surface and the breathable sheet 3, and the sealing part 6 (which is a dot in FIG. 2, but is actually This is a line along the outer frame 1) and is airtightly bonded along the inner edge of the outer frame 1, which has a U-shaped cross section. The space formed between the end of the plate-shaped body 2 and the outer frame 1 serves as a passage for the gas to be separated.

The outer frame 1 can be made of metal, wood, plastic, or any other material that has a certain level of strength. The plate-like body 2 may be a flat metal plate such as aluminum or a plastic plate such as polyacrylic resin whose surface has been roughened with sandpaper, or a plate with thin grooves carved therein. sell. Alternatively, it may be a plate made of foamed plastic that already has a surface roughness, such as hard polyurethane, or even a fibrous material such as felt. The breathable sheet 3 may be made of paper, and for example, thick paper such as No. 131 manufactured by Toyo Paper Co., Ltd. is suitable.

Now, when pressurization is applied from the outside of the module or vacuum suction is performed from the gas permeation port 5 using a vacuum pump, the gas outside the module enters the inside of the module through the composite membrane 4. At this time, inside the module, gas can pass through the gas permeation port 5 through the roughened surface of the plate without creating a large space unlike when a wire mesh is used as in US Pat. No. 3,336,212. It was confirmed that there was sufficient penetration.
A pressure gauge was attached to the frame part of the outer frame 1 at a position exactly opposite to the gas permeation port 5 to be separated, and the pressure loss was measured. For example, when vacuum suction of 150 mmHg was performed from the gas permeation port 5. The pressure gauge showed a pressure loss of 145 mmHg, which was only -5 mmHg.
FIG. 3 is a diagram showing the state of the module surface during pressurization or depressurization operation. A is a conventional example using a wire mesh, and B is a case using the module of the present invention. In case A, the selective gas permeable composite membrane 7 deforms as indicated by d' along the shape of the wire mesh 8, and returns to the original position d when the pressure difference is removed. As this action is repeated, the composite membrane 7 gradually begins to expand, and after approximately 20 repetitions, the composite membrane 7 expands outward from the mesh portion by approximately 5 mm compared to the initial stage. There were cases where pinholes were generated due to repeated use. On the other hand, in the case of B according to the present invention,
No deformation of the composite membrane 4 was observed even after 500 repetitions, and the initial performance was sufficiently maintained.

Although FIG. 1 shows a rectangular module structure, it can be made into any shape depending on the application, such as round or oval, and the gas permeation port 5 to be separated can be By devising 1, it is possible to take out an arbitrary number and arbitrary shape from an arbitrary part of the outer frame 1, for example, in the shape of a slit. In addition, in FIG. 2, the plate-like body 2 is the outer frame 1.
Although it is installed in contact with the outer frame 1, it may be fitted into a recess provided on the inner surface of the outer frame 1, leaving a passage for the gas to be separated. In addition, the composite membrane 4 is
However, there are no particular restrictions on the method of adhesion, and any adhesion method can be used as long as airtightness is maintained, such as heat sealing or using adhesive. It is.

(Example) A rectangular outer frame with a length of 30 cm, a width of 70 cm, a depth of 0.5 cm, and a frame width of 1 cm was made as the outer frame 1, and a foamed phenol resin phenolic manufactured by Mitsui Petrochemicals Co., Ltd. was used as the plate-shaped body 2, and ventilation was carried out. Toyo Paper No. 131 as sex sheet 3
was used. In addition, a module was made using a composite membrane 4 in which polydimethylsiloxane with a thickness of about 2000 Å was installed as a homogeneous membrane on 25 μm porous polypropylene (trade name: Jyuragard).
The composite membrane 4 was adhered to the periphery of the outer frame 1 with a rubber adhesive. Using such a module, the gas permeation port 5
By using a vacuum pump to reduce the pressure to 150 mmHg and sucking in air, we were able to obtain oxygen-enriched air with an oxygen concentration of 32% at a rate of 6.5 per minute. Under these conditions, turn the vacuum pump on and off for 500 seconds.
Although the test was repeated several times, no abnormality occurred in the module or composite membrane. Also, at a constant temperature of 80℃,
After continuous operation for 500 hours, no change was observed.

In this way, the module of the present invention is lightweight, easy to manufacture, and low cost, and exhibits excellent performance in that it does not cause any damage to the membrane part and maintains stable characteristics over a long period of time. Ta.

As described above, the present invention provides a selective gas permeation module that is lightweight, easy to manufacture, low cost, does not cause any damage to the membrane part, and maintains stable performance over a long period of time. This is what we provide.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a selective gas permeation membrane module according to an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional side view of the same part, and Fig. 3 A and B are selective gas permeation membrane modules according to the conventional example and the present invention. FIG. 3 is an explanatory diagram of the operation of the membrane module. DESCRIPTION OF SYMBOLS 1... Outer frame, 2... Plate-shaped body, 3... Breathable sheet, 4... Composite membrane, 5... Gas permeation port.

Claims (1)

[Scope of utility model registration request] A structure comprising at least a non-breathable plate-like body with a roughened surface and an outer frame surrounding the non-breathable plate-like body, and provided to cover at least the surface of the non-breathable plate-like body. A selective gas permeable membrane module comprising an air permeable sheet and a selective gas permeable composite membrane that covers the air permeable sheet and is airtightly provided to an outer frame.