JPH06227803A - Nitrogen generator - Google Patents

Abstract

PURPOSE:To provide a nitrogen generator having high reliability by slowly increasing the pressure on the feed side of raw material compressed air so as not to peel sealing media and a partition material for each gas separation membrane module in relation to the nitrogen generator using the spiral gas separation membrane module utilizing a flat gas separation membrane. CONSTITUTION:The opening and closing degree of an actuator valve 32 or an electrically-operated valve (32a) is controlled so as not to peel sealing media 8 and a partition material 4 of each gas separation membrane module 35. Thereby, raw material compressed air fed to the gas separation membrane module 35 is made to require >=1min time for its pressure to attain 5kgf/cm<2>G.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supplying raw material air to a nitrogen generator using a spiral gas separation membrane module formed by winding a flat membrane gas separation composite membrane.

[0002]

2. Description of the Related Art Generally, a spiral separation membrane module formed by winding a flat membrane has a permeation fluid flow path material forming a permeation fluid flow path sandwiched between flat membrane separation membranes to form a hole in a hollow tube. A flat membrane separation membrane is adhered to the hollow tube so that the permeate fluid channels communicate with each other, and the flat tube separation membrane is wound around the hollow tube together with the raw material fluid channel material forming the raw material fluid channel. In addition, the end faces of the two sides of the flat membrane separation membrane (which sandwiches the permeating fluid flow channel material) perpendicular to the side of the flat membrane separation membrane bonded to the hollow tube are sealed, and the raw material fluid flow channel is Has been released.

Separation of fluid in a conventional separation membrane module,
Concentration A case where the raw material fluid is air and nitrogen is separated and concentrated will be described below.

FIG. 5 shows an example of a conventional spiral gas separation membrane module. When the raw material air is supplied in the direction of the arrow (solid line) to the raw material gas supply passage constituted by the raw material gas supply passage material 22, the raw material air opposes the surface of the gas separation composite membrane 21 that preferentially permeates oxygen. It flows in the direction of the side. At that time, oxygen preferentially permeates the gas separation composite membrane 21, and the permeable gas flow path constituted by the permeable gas flow path member 23 is passed through the hollow tube 24.
It flows in the direction of (arrow: broken line). Therefore, nitrogen is concentrated in the air coming out from the side opposite to the side where the raw material air is supplied.

Gas separation and concentration by a gas separation membrane is a process in which a raw material gas flows while being in contact with the surface of a gas separation composite membrane, and gases that easily permeate through the gas separation composite membrane successively pass through the gas separation composite membrane. The gas on the surface will be concentrated,
The longer the gas separation composite membrane, the more concentrated the gas on the surface of the gas separation membrane.

[0006]

However, the above-mentioned conventional structure has a problem that air having a high nitrogen concentration cannot be obtained because the raw material air flows over the surface of the gas separation composite membrane for a short distance. Was there.

The present invention solves the above problems, and an object of the present invention is to provide a highly reliable nitrogen generator capable of obtaining air having a high nitrogen concentration.

[0008]

In order to achieve this object, a gas separation membrane module of a nitrogen generator according to the present invention comprises a raw material gas passage material, a flat membrane-like gas separation composite membrane, and a permeation gas passage. The material and the partitioning material that separates the raw material gas passage and the permeated gas passage are stacked in the above order to form one unit, and the supply pipe that supplies the raw material air and the exhaust pipe that exhausts the permeated gas are integrated. A gas separation membrane module that is spirally wound around an exhaust pipe. The raw gas passage and the supply pipe of the supply / exhaust pipe communicate with one side of the winding start, and the permeate gas passage and the exhaust pipe of the supply / exhaust pipe are connected. The gas separation composite membrane and the partition material are bonded to the air supply / exhaust pipe so that they communicate with each other, the gas separation composite membrane and the partition material are bonded to one end of the winding so as to close the gas permeation flow path, and the other two sides are bonded. It has a structure in which the raw material gas passage and the permeation gas passage are hermetically sealed.

Then, an actuator valve or an electric valve is used so that the raw material gas flow path of the gas separation membrane module is not suddenly pressed and the sealing material and the gas separation membrane and the sealing material and the partition material are separated from each other. Then, means for gradually increasing the pressure on the raw material compressed air supply side is provided.

[0010]

With this configuration, since the raw material gas supplied from the supply pipe flows in the direction in which the raw material gas flow path is wound, the length of the gas separation composite membrane is lengthened so that the raw material gas flow path is It can be lengthened. Since the raw material gas flows while being in contact with the surface of the gas separation composite membrane, the gas that easily permeates the gas separation composite membrane will pass one after another,
The longer the gas separation composite membrane, the more concentrated the gas on the surface of the gas separation membrane.

Further, since the pressure on the side of the raw material air supply of the gas separation membrane module gradually rises, the pressure in the raw material gas passage does not rise sharply, and the sealant, the gas separation membrane, the sealant, and the partitioning member are separated. Does not peel off, resulting in higher reliability.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a nitrogen generator according to the first embodiment, FIG. 2 is a nitrogen generator according to the second embodiment, and FIG. 3 is a sectional view taken along the line AA 'of the gas separation membrane module according to the present embodiment. FIG. 4 is a sectional view of the gas separation membrane module of this embodiment.

(Embodiment 1) FIG. 1 shows a nitrogen generator containing three gas separation membrane modules shown in FIGS. 3 and 4.
In FIG. 1, 31 is a first compressed air supply pipe, 32 is an actuator valve, 33 is a pressure adjusting valve, and 34 is a second.
Compressed air supply pipe, 35 is a gas separation membrane module, 10
Is a flow rate control valve, 36 is a nitrogen enriched air supply pipe, and 37 is an oxygen enriched air supply pipe.

In FIGS. 3 and 4, reference numeral 1 is a raw material gas flow path member, which is a 15-mesh polyethylene molding net.
Reference numeral 2 denotes a gas separation composite membrane, which has an asymmetric structure in which a gas separation membrane of poly (4-methylpentene 1) is laminated on a porous support, and polydimethylsiloxane is further laminated thereon, and the separation membrane side is the raw material gas flow path member 1 And the one side of the winding start is air-tightly bonded to the air supply / exhaust pipe 5.

Reference numeral 3 denotes a permeating gas flow channel material, which is a 15-mesh polyethylene molding net. 4 is a partition material, thickness 10
It is a polyester film of 0 μm, and one side of the winding start is airtightly bonded to the air supply / exhaust pipe 5. Reference numeral 5 denotes an air supply / exhaust pipe in which an air supply pipe 6 and an exhaust pipe 7 are arranged in parallel in the length direction.

The above materials 1 to 4 are spirally wound around the air supply / exhaust pipe 5, and then the gas separation composite membrane 2 and the partition member 4 are airtightly adhered to each other on one side of the winding end and the other two sides. Figure 4
As described above, the raw material gas flow path and the permeation gas flow path are adhesively sealed by the sealant 8 so as to be airtightly separated from each other.

The gas separation membrane module configured as described above is housed in the pressure vessel 9, and the air supply pipe 6 is connected to 592 Pa.
Air pressurized to (5 kgf / cm ² G) 4.2 × 10
^-4 m ³ / s (25 l / min) is supplied, and the flow control valve 1
The flow rate of nitrogen-enriched air obtained from 0 is 8.3 × 10 ⁻⁵ m ³
/ S (5 l / min) was adjusted to a nitrogen concentration of 9
It was 7.5%.

The nitrogen generator shown in FIG. 1 accommodates three gas separation membrane modules 35 made as described above so that the pressure in the gas separation membrane module 35 does not rise sharply.
The pressure adjustment valve 33 is set, and the actuator valve 32 is set.
The time until the pressure of the raw material compressed air supplied to the second compressed air supply pipe 34 reaches 5 kgf / cm ² G is 1 m.
By applying more than in, the gas separation membrane module 35
The gas separation composite membrane 2, the sealant 8 and the partition member 4 do not separate. Further, the adhesive portion between the air supply / exhaust pipe 5 of the gas separation membrane module 35 and the pressure vessel 9 is not peeled off.

From the above results, the second compressed air supply pipe 3
The pressure of the raw material compressed air supplied to No. 4 is 5 kgf / cm ² G
It takes more than 1 min to reach 592 Pa (5 kg
Air reaching f / cm ² G) 12.6 × 10 ⁻⁴ m ³ / s
(75 l / min) to the gas separation membrane module 35 (3
The flow rate of nitrogen-enriched air obtained from the flow control valve 10 is 24.9 × 10 ⁻⁵ m ³ / s (15 l / min).
When adjusted to, it was possible to obtain nitrogen-enriched air with a nitrogen concentration of 97.5%.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a second embodiment.

In FIG. 2, 31 is a first compressed air supply pipe, 32a is a motor valve, 33b is a motor, 34 is a second compressed air supply pipe, 35 is a gas separation membrane module, 1
Reference numeral 0 is a flow rate control valve, 36 is a nitrogen enriched air supply pipe, and 37 is an oxygen enriched air supply pipe.

In FIG. 2, the actuator valve 32 of FIG. 1 is used as a motor valve 32a, and the pressure adjustment bubble 33 is used as a motor 3.
3b is different from the first embodiment in that it is changed to 3b, and the following is the same. The actuator valve 32 is different in that the opening / closing degree of the actuator valve 32 is controlled by a pressure adjusting valve 33, whereas the motor valve 32a is controlled by a motor 33b.

The motor 33b controls the opening / closing degree of the motor valve 32a, and it takes 1 min or more for the pressure of the raw material compressed air supplied to the second compressed air supply pipe 34 to reach 5 kgf / cm ² G, and 592 Pa (5 kgf / c).
Air 12.6 × reaching ^{m 2 G) 10 -4 m 3} / s (75l
/ Min) is supplied to the gas separation membrane module 35 (three), and the nitrogen-concentrated air flow rate obtained from the flow rate control valve 10 is set to 2
When adjusted to 4.9 × 10 ⁻⁵ m ³ / s (15 l / min), nitrogen enriched air with a nitrogen concentration of 97.5% could be obtained.

[0025]

As described above, according to the present invention, a raw material air flow path member, a flat membrane gas separation composite membrane, a permeable gas flow path member, a raw material gas flow path and a permeable gas flow path are provided. Separating partition material into one unit by stacking them in the above order, and a gas separation spirally wound around an air supply / exhaust pipe in which an air supply pipe for supplying raw material air and an exhaust pipe for discharging permeated gas are integrated. In the membrane module, the gas separation composite membrane is connected to the supply / exhaust pipe so that the raw material gas flow passage and the supply / exhaust pipe of the supply / exhaust pipe communicate with one side of the winding start and the permeate gas flow passage and the exhaust pipe of the supply / exhaust pipe communicate with each other. And a partition material are bonded, the gas separation composite membrane and the partition material are bonded so that one side of the winding end closes the permeated gas channel, and the other two sides air-tightly separate the raw material gas channel and the permeated gas channel. By sealing in this way, a gas separation membrane module with high concentration efficiency can be obtained and Tabarubu or use the motor valve, provided with means for the pressure of the feed compressed air supply side gradually increase pressure of the feed compressed air 5 kgf / c,
By adjusting so that it takes 1 min or more to reach m ² G, the raw material gas flow path of the gas separation membrane module is not suddenly applied with pressure, and the sealant and the gas separation membrane and the sealant are separated from each other. Since it does not peel off from the material, it can be a highly reliable nitrogen generator.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a nitrogen generator according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a nitrogen generator according to a second embodiment of the present invention.

FIG. 3 is a developed sectional view of a gas separation membrane module of a nitrogen generator according to an embodiment of the present invention.

FIG. 4 is a schematic explanatory diagram of a gas separation membrane module of a nitrogen generator according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a conventional spiral separation membrane module.

[Explanation of symbols]

 1 Raw Material Gas Channel Material 2 Gas Separation Composite Membrane 3 Permeation Gas Channel Material 4 Partition Material 5 Air Supply / Exhaust Pipe 6 Air Supply Tube 7 Exhaust Pipe 8 Sealant 9 Pressure Vessel 10 Flow Control Valve 31 First Compressed Air Supply Pipe 32 Actuator Valve 32a Motor valve 33 Pressure adjustment valve 33b Motor 34 Second compressed air supply pipe 35 Gas separation membrane module 36 Nitrogen concentrated air supply pipe 37 Oxygen concentrated air supply pipe

Claims (3)

[Claims] 1. A raw material gas flow path member, a flat membrane-like gas separation composite membrane, a permeating gas flow path member, and a partitioning member for separating the raw material gas flow path and the permeating gas flow path are stacked in the above order. One unit,
A gas separation membrane module spirally wound around a supply / exhaust pipe in which a supply pipe for supplying raw material air and an exhaust pipe for exhausting permeated gas are integrated. Adhere the gas separation composite membrane and partition material to the supply / exhaust pipe so that the supply pipe of the exhaust pipe communicates with the exhaust gas pipe of the supply / exhaust pipe, and the permeate gas flow on one side of the winding end. A gas separation membrane module in which a gas separation composite membrane and a partitioning material are adhered so as to close a passage, and the other two sides are sealed so that a raw material gas passage and a permeation gas passage are airtightly separated, and a gas separation membrane. And a means for gradually increasing the pressure of the raw material compressed air supplied to the module. 2. The means for gradually increasing the pressure of the raw material compressed air supplied to the gas separation membrane module is such that the pressure of the raw material compressed air supplied to the gas separation membrane module is 5 kg.
The nitrogen generator according to claim 1, wherein the time required to reach f / cm ² G is 1 min or more. 3. The nitrogen generator according to claim 1, wherein the means for gradually increasing the pressure of the raw material compressed air supplied to the gas separation membrane module comprises an actuator valve or an electric valve.