JP7289908B1 - Pressure Swing Adsorption Gas Separator - Google Patents

Abstract

The present invention provides a pressure swing adsorption gas separation apparatus capable of recovering easily adsorbable components of high purity. Kind Code: A1 Adsorption cylinders (10B, 10U, 11B, 11U) filled with an adsorbent that easily adsorbs one or more components and hardly adsorbs other components, and a raw material gas is stored. a source gas storage tank 1, an easily adsorbable component storage tank 2 for storing easily adsorbable components, paths (first flow paths) L4 and L5 located between the compressor 4 and the adsorption cylinders 10B and 11B, Paths (second flow paths) L11, L12 branched from paths L4, L5 at branch points (first branch points) P, Q and located between the branch points P, Q and the easily adsorbable component storage tank 2; , on-off valves (first on-off devices) V13 and V12 located on paths L11 and L12, and the on-off valves V13 and V12 are located near branch points P and Q. select. [Selection drawing] Fig. 1

Description

The present invention relates to a pressure swing adsorption gas separation device.

2. Description of the Related Art In the process of manufacturing semiconductor products such as semiconductor integrated circuits and liquid crystal panels, an apparatus is widely used in which plasma is generated by high-frequency discharge in a rare gas atmosphere and the plasma is used to perform various processes on semiconductor products or display devices. Conventionally, argon has been used as the rare gas used in such processing, but krypton and xenon have been attracting attention in recent years in order to perform more advanced processing. However, since krypton and xenon are extremely rare and expensive gases due to their abundance in air and the complexity of the separation process, it is extremely important to recover and reuse used noble gases. . In order to reuse the rare gas, a concentration of at least 99% is required.

Here, as a device for separating xenon or krypton, a raw material gas containing xenon or krypton and other impurity components should be easily adsorbed to xenon or krypton and difficult to adsorb other impurity components. Flow it into an adsorption cylinder filled with an adsorbent, and let the adsorbent adsorb xenon or krypton, which are easily adsorbable components. There is a method of desorbing krypton from an adsorbent and recovering it at a high concentration.

For example, in Patent Document 1, the source gas in the source gas storage tank is pressurized and flowed into two adsorption cylinders (upper cylinder and lower cylinder) connected in series to adsorb xenon or krypton, which are easily adsorbable components, and Step (a) for separating impurities that are difficult to adsorb components, and xenon or krypton filled in the easily adsorbable component storage tank is pressurized and introduced into the lower cylinder, and the impurities that are difficult to adsorb components remaining in the voids are transferred to the upper cylinder. step b, in which the easily adsorbed components, xenon or krypton, are adsorbed in the upper cylinder, and impurities, which are difficultly adsorbed components, are recovered from the upper cylinder; Step (c) in which the adsorbent is desorbed from the adsorbent and collected in a storage tank for easily adsorbable components; Step d of collecting in a gas storage tank, introducing the previously collected impurities, which are poorly adsorbable components, into the upper cylinder, desorbing the easily adsorbable components, xenon or krypton, from the adsorbent and introducing it into the lower cylinder, and A separation method is disclosed which includes a step e of recovering the gas that has flowed out from the lower cylinder into a raw material gas storage tank, and sequentially performs these steps a to e according to a sequence.

Further, Patent Document 1 discloses a flow path for pressurizing and introducing the raw material gas from the raw material gas storage tank, a flow path for pressurizing and introducing the gas from the easily adsorbable component storage tank, and an upper tube of the adsorption tube. A flow path connected to the cylinder, a flow path for depressurizing and discharging to the source gas storage tank, and a flow path for depressurizing and discharging to the readily adsorbable component storage tank are located, and each flow path has a valve to control the gas flow. A provided apparatus is disclosed. In the device disclosed in Patent Document 1, piping necessary for connecting the valves is provided between the lower cylinder and the valves provided in these flow paths.

JP-A-2006-61831

The separation method and apparatus disclosed in Patent Document 1 have the following problems.
In the above-described step a, as shown in FIG. 1 of Patent Document 1, the raw material gas introduced from the raw material gas storage tank 1 into the lower cylinder 10B is connected from the lower cylinder 10B to the easily adsorbable component storage tank 2. It flows into the pipe between the valve V12 provided at L9 and the lower cylinder 10B.
Next, in step b described above, the easily adsorbable component gas in the easily adsorbable component storage tank 2 is introduced into the lower cylinder 10B through the pipe L4. However, since no readily adsorbable component gas flows in the vicinity of the valve V12 between the valve V12 and the lower cylinder 10B in the pipe L9, the source gas continues to exist.
As a result, in the above-described step c, the raw material gas present in the vicinity of the valve V12 between the valve V12 and the lower cylinder 10B in the above-described pipe L9 is discharged to the easily adsorbable component storage tank 2. . Since the weakly adsorbable components contained in the source gas are impurities in the easily adsorbable component gas in the easily adsorbable component storage tank 2, they cause a decrease in the purity of the separated easily adsorbable components. In particular, when the concentration of the difficult-to-adsorb components in the raw material gas is high, even if the volume between the valve V12 and the lower cylinder 10B in the above-described pipe L9 is small, it significantly reduces the purity.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pressure swing adsorption gas separation apparatus capable of recovering high-purity easily adsorbable components.

In order to solve the above problems, the present invention has the following configuration.
[1] An apparatus for separating and recovering two or more components from a raw material gas using a pressure swing adsorption gas separation method,
one or more adsorption cylinders filled with an adsorbent that easily adsorbs one or more of the components and has poor adsorption of the other components;
a source gas storage tank for storing the source gas;
an easily adsorbable component storage tank for storing the easily adsorbable component led out from the adsorption cylinder;
a compressor that compresses the gas drawn out from the source gas storage tank or the easily adsorbable component storage tank and supplies the gas to the adsorption column;
a first flow path positioned between the compressor and the adsorption tower;
a second flow path branched from the first flow path at a first branch point and positioned between the first branch point and the easily adsorbable component storage tank;
a first opening and closing device located in the second flow path,
The pressure swing adsorption gas separation device, wherein the first opening/closing device is positioned near the first branch point.
[2] The pressure swing adsorption gas separation apparatus according to [1], wherein the first branch point is located closer to the adsorption tower.
[3] a third flow path branched from the first flow path at a second branch point and positioned between the second branch point and the source gas storage tank;
a second opening and closing device located in the third flow path,
The pressure swing adsorption gas separation device according to [1] or [2], wherein the second opening/closing device is located near the second branch point.
[4] The pressure swing adsorption gas separation apparatus according to [3], wherein the second branch point is located closer to the adsorption tower.

INDUSTRIAL APPLICABILITY The pressure swing adsorption gas separation apparatus of the present invention is capable of recovering easily adsorbable components of high purity.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram showing the configuration of a pressure swing adsorption gas separation apparatus according to a first embodiment of the present invention; FIG. 2 is a schematic diagram showing the configuration of a pressure swing adsorption gas separation apparatus according to a second embodiment of the present invention;

It should be noted that the dimensions and the like of the drawings illustrated in the following description are only examples, and the present invention is not necessarily limited to them, and can be implemented with appropriate changes within the scope of not changing the gist of the present invention. .

<First Embodiment>
First, a pressure swing adsorption gas separation apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of a pressure swing adsorption gas separation apparatus 50 according to the first embodiment of the present invention.
As shown in FIG. 1, a pressure swing adsorption gas separation apparatus (hereinafter also simply referred to as "PSA apparatus") 50 of the present embodiment includes a source gas storage tank 1 for storing a source gas containing two or more components; Easily adsorbable component storage tank 2 for storing easily adsorbable components (easily adsorbable components), difficultly adsorbable component storage tank 3 for storing difficultly adsorbable components (hardly adsorbable components), compressor 4, compressor 5, lower cylinder 10B, 11B, upper cylinders 10U, 11U, four adsorption cylinders, paths L1 to L17, and on-off valves V1 to V15. The PSA apparatus 50 of this embodiment is an apparatus for separating these components from a source gas containing two or more components using a pressure swing adsorption gas separation method and recovering each of these components as high-concentration gas components.

The source gas storage tank 1, the easily adsorbable component storage tank 2, and the poorly adsorbable component storage tank 3 are all containers capable of storing gas components (source gas, easily adsorbable components, and difficultly adsorbable components). The shape and size (capacity) of these containers are not particularly limited, and can be appropriately selected according to the supply amount, collection amount, and the like. Moreover, the material of these containers is not particularly limited as long as it is a material that does not corrode with the stored gas.

A source gas is a mixed gas containing two or more components. The mixed gas is not particularly limited as long as it contains two or more gas components. Such a mixed gas includes, for example, a mixed gas containing two gas components, nitrogen gas and xenon.

The lower cylinders 10B and 11B and the upper cylinders 10U and 11U are adsorption cylinders each having an inner space of a cylindrical container filled with an adsorbent. The shape and size (capacity) of these adsorption cylinders are not particularly limited, and can be appropriately selected according to the amount of supply, the amount of recovery, and the like. Also, the material of these adsorption cylinders is not particularly limited as long as it is a material that does not corrode with the stored gas.

The lower cylinders 10B and 11B and the upper cylinders 10U and 11U are each filled with an adsorbent. The adsorbent is not particularly limited as long as it easily or hardly adsorbs the target component in the raw material gas and has difficulty or easy adsorption of components other than the target component. .

For example, when the source gas is a mixed gas containing two gas components, nitrogen gas and xenon, activated carbon can be used as the adsorbent. Here, activated carbon has properties such that the amount of xenon adsorbed is large (easily adsorbable) and the amount of nitrogen adsorbed is small (difficultly adsorbable) as the equilibrium adsorption amount.

Paths L1 to L17 are gas paths for introducing gas to each structure described above or for discharging gas from each structure.
A route L1 is a route for introducing the raw material gas into the raw material gas storage tank 1 .
One end of the path L2 is connected to the source gas storage tank 1, and the other end is connected at a branch point T to the path L3 and the path L15. That is, the path L2 is a part of the gas path that leads the gas in the raw material gas storage tank 1 to the compressor 4 .
One end of the route L3 is connected to the easily adsorbable component storage tank 2, and the other end is connected at a branch point T to the route L2 and the route L15. In other words, the path L3 is a part of the gas path that leads the gas in the easily adsorbable component storage tank 2 to the compressor 4 .

Path L4 branches from path L15 and is connected to lower tube 10B. That is, the path L4 is a part of the gas path (first flow path) that introduces the compressed gas drawn out from the compressor 4 into the lower cylinder 10B. Branch points P and R are located on the primary side of the lower cylinder 10B of the path L4.
Path L5 branches from path L15 and is connected to lower tube 11B. That is, the path L5 is part of the gas path (first flow path) that introduces the compressed gas drawn out from the compressor 4 into the lower cylinder 11B. Branch points Q and S are located on the primary side of the lower cylinder 11B of the path L5.

A route L6 is a gas route that merges with the routes L4 and L5, respectively, and introduces the weakly adsorbable components derived from the upper cylinders 10U and 11U into the poorly adsorbable component storage tank 3.
A route L7 is a gas route for discharging the weakly adsorbable component derived from the poorly adsorbable component storage tank 3 to the outside of the apparatus system.
The path L8 is a part of the gas path that introduces the weakly adsorbable components drawn out from the poorly adsorbable component storage tank 3 into the upper cylinders 10U and 11U, respectively.

The path L9 is connected to the lower cylinder 10B via the path L4, and is connected to the source gas storage tank 1 via the path L17. Specifically, the route L9 branches off from the route L4 at a branch point (second branch point) R located on the route L4 (first flow path) and merges with the route L10 and the route L17. That is, the path L9 is located between the path L4 and the path L17 and is part of the flow path (third flow path) for returning the gas from the lower cylinder 10B to the source gas storage tank 1.
The path L10 is connected to the lower cylinder 11B via a path L5, and is connected to the source gas storage tank 1 via a path L17. Specifically, the route L10 branches from the route L5 at a branch point (second branch point) S located on the route L5 (first flow path) and merges with the route L9 and the route L17. That is, the path L10 is located between the path L5 and the path L17, and is part of the flow path (third flow path) for returning the gas from the lower cylinder 11B to the source gas storage tank 1.

Path L11 is connected to lower cylinder 10B via path L4, and is connected to easily adsorbable component storage tank 2 via path L16. Specifically, the route L11 branches off from the route L4 at a branch point (first branch point) P located on the route L4 (first flow path) and merges with the route L12 and the route L16. That is, the path L11 is located between the path L4 and the path L16 and is part of the flow path (second flow path) for returning the gas from the lower cylinder 10B to the easily adsorbable component storage tank 2.
Path L12 is connected to lower cylinder 11B via path L5, and is connected to easily adsorbable component storage tank 2 via path L16. Specifically, the route L12 branches off from the route L5 at a branch point (first branch point) Q located on the route L5 (first flow path) and merges with the route L11 and the route L16. That is, the path L12 is located between the path L5 and the path L16 and is part of the flow path (second flow path) for returning the gas from the lower cylinder 11B to the easily adsorbable component storage tank 2.

The path L13 is connected to the easily adsorbable component storage tank 2 and is a path for supplying the easily adsorbable component from the easily adsorbable component storage tank 2 to the outside of the apparatus system.
The path L14 is a pressure equalizing line positioned between the upper cylinder 10U and the upper cylinder 11U to equalize the pressure between the upper cylinder 10U and the upper cylinder 11U.

One end of the path L15 branches into a path L4 and a path L5. The path L15 communicates with the lower cylinders 10B and 11B through the paths L4 and L5, respectively. do. That is, the path L15 is located between the compressor 4 and the lower cylinders 10B and 11B (adsorption towers), and is a gas path (second 1 channel).
One end of the path L16 branches into the path L11 and the path L12, and the other end is connected to the easily adsorbable component storage tank 2. That is, the path L16 is located between the branch points (first branch points) P, Q and the easily adsorbable component storage tank 2, and is a flow path for returning the gas from the lower cylinders 10B, 11B to the easily adsorbable component storage tank 2. It is part of the channel (second channel).
One end of the path L17 branches into a path L9 and a path L10, and the other end is connected to the source gas storage tank 1. That is, the path L17 is positioned between the lower cylinders 10B, 11B and the raw material gas storage tank 1, and serves as a flow path (third flow path) for returning the gas from the lower cylinders 10B, 11B to the raw material gas storage tank 1. It is part.

The compressor 4 is located on the path L15, and the raw material gas is led out to the path L15 from the source gas storage tank 1 via the path L2, and the easily adsorbable component storage tank 2 is led out to the path L15 via the path L3. After one of the easily adsorbable components is pressurized (compressed), it is supplied to the lower cylinder 10B or the lower cylinder 11B via the path L4 or the path L5.

The compressor 4 is not particularly limited as long as it can pressurize (compress) the gas component. Examples of such a compressor 4 include a diaphragm compressor.
Also, the discharge amount of the compressor 4 is not particularly limited, and can be appropriately selected according to the supply amount, recovery amount, and the like of the gaseous component.

The compressor 5 is located on the path L13, and after pressurizing (compressing) the easily adsorbable component led out from the easily adsorbable component storage tank 2 to the path L13, supplies it to the outside of the system. The compressor 5 is not particularly limited as long as it can pressurize (compress) the gas component. Such a compressor 5 may be, for example, a diaphragm compressor. Also, the discharge amount of the compressor 5 is not particularly limited, and can be appropriately selected according to the supply amount, recovery amount, and the like of the gaseous component.

The on-off valves V1 to V15 are opening/closing devices positioned in the paths L2 to L14, respectively, for opening or closing the flow paths of the gas components in the paths.
In the PSA device 50 of the present embodiment, among these on-off valves, the on-off valve (first opening/closing device) V12 located on the path L11 is located near the branch point (first branch point) P.

Here, the position of the on-off valve V12 near the branch point P means that the distance between the on-off valve V12 and the branch point P is short. As a result, the volume in the path between the on-off valve V12 and the branch point P can be reduced. That is, when the gas discharged from the lower cylinder 10B is discharged to the easily adsorbable component storage tank 2, the amount of gas remaining in the path L11 between the on-off valve V12 and the branch point P can be reduced.

The amount of gas remaining in the path L11 from the on-off valve V12 to the branch point P (residual gas amount) is determined by the volume of the piping forming the path L11 from the on-off valve V12 to the branch point P, and the volume of the on-off valve V12 is the sum of the internal volume of
In the PSA device 50 of this embodiment, the volume of the path L11 from the inside of the on-off valve V12 to the branch point P is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute.

Similarly, in the PSA device 50 of the present embodiment, the on-off valve (first opening/closing device) V13 located on the path L12 is located near the branch point (first branch point) Q among these on-off valves.

Here, the position of the on-off valve V13 near the branch point Q means that the distance between the on-off valve V13 and the branch point Q is short. As a result, the volume in the path between the on-off valve V13 and the branch point Q can be reduced. That is, when the gas discharged from the lower cylinder 11B is discharged to the easily adsorbable component storage tank 2, the amount of gas remaining in the path L12 between the on-off valve V13 and the branch point Q can be reduced.

The amount of gas remaining in the path L12 from the on-off valve V13 to the branch point Q (residual gas amount) is determined by the volume of the piping forming the path L12 from the on-off valve V13 to the branch point Q, and the volume of the on-off valve V13 is the sum of the internal volume of
In the PSA device 50 of the present embodiment, the volume of the path L11 from the inside of the on-off valve V13 to the branch point Q is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute.

In addition, in the PSA device 50 of the present embodiment, among these on-off valves, the on-off valve (second opening/closing device) V10 located on the path L9 is preferably located near the branch point (second branch point) R. .

Here, the position of the on-off valve V10 near the branch point R means that the distance between the on-off valve V10 and the branch point R is short. As a result, the volume in the path between the on-off valve V10 and the branch point R can be reduced. That is, the amount of gas remaining in the path L9 between the on-off valve V10 and the branch point R can be reduced when the gas discharged from the lower cylinder 10B is discharged to the source gas storage tank 1.

The amount of gas remaining in the path L9 from the on-off valve V10 to the branch point R (residual gas amount) is determined by the volume of the piping that forms the path L9 from the on-off valve V10 to the branch point R, and the volume of the on-off valve V10. is the sum of the internal volume of
In the PSA device 50 of this embodiment, the volume of the path L9 from the inside of the on-off valve V10 to the branch point R is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute.

Similarly, in the PSA device 50 of the present embodiment, among these on-off valves, the on-off valve (second opening/closing device) V11 located on the path L10 is preferably located near the branch point (second branch point) S. .

Here, the position of the on-off valve V11 near the branch point S means that the distance between the on-off valve V11 and the branch point S is short. As a result, the volume in the path between the on-off valve V11 and the branch point S can be reduced. That is, when the gas discharged from the lower cylinder 11B is discharged to the source gas storage tank 1, the amount of gas remaining in the path L10 between the on-off valve V11 and the branch point S can be reduced.

The amount of gas remaining in the route L10 from the on-off valve V11 to the branch point S (residual gas amount) is determined by the volume of the pipe forming the route L10 from the on-off valve V11 to the branch point S, and the volume of the on-off valve V11. is the sum of the internal volume of
In the PSA device 50 of this embodiment, the volume of the path L10 from the inside of the on-off valve V11 to the branch point S is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute.

The on-off valves V10 to V13 are not particularly limited as long as they can reduce the amount of gas remaining in the piping that serves as the gas component flow path. Such on-off valves include ball valves, rotary valves, bellows valves, diaphragm valves, and the like.
These are preferable because the volume inside the on-off valve can be reduced.
Further, among the ball valves, a three-way flow switching type ball valve is more preferable because the piping volume can be made extremely small.
Furthermore, among bellows valves and diaphragm valves, block types such as three-way split type and double three-way valves, in which multiple valves are made up of one block, can make the piping volume extremely small and have excellent valve driving durability. , highly preferred.

In addition, in the PSA device 50 of the present embodiment, it is preferable that the branch point (first branch point) P and the branch point (second branch point) R described above are located closer to the lower tube 10B on the path L4.
Similarly, in the PSA device 50 of the present embodiment, the above-described branch point (first branch point) Q and branch point (second branch point) S are preferably located near the lower cylinder 11B of the path L5. .

Here, the bifurcation points P and R positioned closer to the lower tube 10B means that the distance between the bifurcation points P and R and the lower tube 10B is short. As a result, the volume in the path L4 between the branch points P, R and the lower cylinder 10B can be reduced. That is, when the gas discharged from the lower cylinder 10B is led out to the source gas storage tank 1 or the easily adsorbable component storage tank 2, the amount of gas remaining in the path L4 between the branch points P, R and the lower cylinder 10B is can be reduced.
In the PSA device 50 of the present embodiment, the volume of the path L4 between the branch points P, R and the lower cylinder 10B is preferably 1% by volume or less of the gas volume sucked by the compressor 4 per minute. .

Similarly, the position of the branch points Q and S closer to the lower cylinder 11B means that the distance between the branch points Q and S and the lower cylinder 11B is short. As a result, the volume in the path L5 between the branch points Q, S and the lower cylinder 11B can be reduced. That is, when the gas discharged from the lower cylinder 11B is led out to the source gas storage tank 1 or the easily adsorbable component storage tank 2, the amount of gas remaining in the path L5 between the branch points Q and S and the lower cylinder 11B is can be reduced.
In the PSA device 50 of the present embodiment, the volume of the path L5 between the branch points Q, S and the lower cylinder 11B is preferably 1% by volume or less of the gas volume sucked by the compressor 4 per minute. .

Further, in the PSA device 50 of the present embodiment, a concentration meter may be installed in each flow path described above.
Specific positions of the densitometers include a path L4 between the on-off valve V3 and the branch point R, a path L11 between the on-off valve V12 and the branch point P, and a path between the on-off valve 10 and the branch point R. L10, a route L5 between the on-off valve V4 and the branch point S, a route L12 between the on-off valve V13 and the branch point Q, and a route L11 between the on-off valve 11 and the branch point S.
Further, each densitometer is closer to the branch point R on the route L4, closer to the branch point P on the route L11, closer to the branch point R on the route L10, closer to the branch point S on the route L5, and a branch point Q on the route L12. It is preferable to provide it near the branch point S on the route L11.

Next, a method of operating the pressure swing adsorption gas separation apparatus 50 of this embodiment will be described.
In the following description, a mixed gas containing two gas components, nitrogen gas and xenon, is used as the raw material gas, and an equilibrium separation type A case of using activated carbon as an adsorbent will be described as an example.

In the method of operating the PSA device 50 of the present embodiment, first, in the lower cylinder 10B and the upper cylinder 10U, (1) an adsorption step, (2) a rinse step, (3) a lower cylinder pressure reduction step, and (4) an upper cylinder pressure reduction step , (5) a purge regeneration process, and (6) a pressure equalization pressurization process.

(1) Adsorption Step First, in the adsorption step, the on-off valves V2, V4, V7, V9, V10 and V12 are closed, the on-off valves V1, V3, V5 and V14 are opened, and the After the mixed gas is compressed by the compressor 4, it is introduced into the lower part of the lower cylinder 10B via the paths L15 and L4.
Here, the lower cylinder 10B and the upper cylinder 10U communicate with each other because the on-off valve V5 is open, and the pressure rises in substantially the same manner.
The mixed gas discharged from the raw material gas storage tank 1 is composed of the raw material gas introduced into the raw material gas storage tank 1 from the path L1 and the lower cylinder 10B or 11B in the upper cylinder decompression process and the purge regeneration process described later. It is a mixed gas with

Next, as the mixed gas introduced into the lower part of the lower cylinder 10B advances to the upper part of the lower cylinder 10B, xenon is preferentially adsorbed by the adsorbent, and nitrogen is concentrated in the gas phase. The concentrated nitrogen is introduced from the upper part of the lower cylinder 10B to the lower part of the upper cylinder 10U, and in the upper cylinder 10U, a small amount of xenon contained in the nitrogen is further adsorbed by the adsorbent. After the pressure in the upper tube 10U becomes higher than the pressure in the weakly adsorbable component storage tank 3, the nitrogen further concentrated in the upper tube 10U is led out to the weakly adsorbable component storage tank 3 via the path L6.
The nitrogen stored in the difficult-to-adsorb component storage tank 3 is discharged out of the system through the path L7 at a flow rate corresponding to the nitrogen contained in the raw material gas, and the remaining nitrogen is used as a countercurrent purge gas in the purge regeneration step described later. used as

(2) Rinsing Step Next, in the rinsing step, the on-off valve V1 is closed and the on-off valve V2 is opened to introduce the xenon drawn out from the easily adsorbable component storage tank 2 into the lower portion of the lower cylinder 10B. By introducing xenon, which is an easily adsorbed component, into the lower cylinder 10B, the nitrogen co-adsorbed in the adsorbent packed layer of the lower cylinder 10B and the nitrogen present in the pores of the adsorbent are transferred from the lower cylinder 10B to the upper cylinder 10U. , and the inside of the lower cylinder 10B is saturated with xenon. Next, by closing the on-off valves V7, V8, V14 and V15 and opening the on-off valve V9, the nitrogen discharged from the upper part of the upper cylinder 10U is sent to the upper cylinder 11U via the path L14.

(3) Lower cylinder decompression process Next, in the lower cylinder decompression process, the on-off valves V3, V5, and V10 are closed, and the on-off valve V12 is opened. As a result, the xenon adsorbed in the lower cylinder 10B during the above-described adsorption process and rinsing process flows through the paths L11 and L16 due to the pressure difference between the lower cylinder 10B and the easily adsorbable component storage tank 2. It is collected in the storage tank 2 . The xenon recovered in the easily adsorbable component storage tank 2 is compressed by the compressor 5 at a flow rate corresponding to the xenon contained in the raw material gas, and then extracted as a product from the path L13, and the remaining xenon is the above-mentioned xenon. Used as a co-current purge gas in the rinse step.
During the lower cylinder decompression process, the on-off valves V5, V7, V9, and V14 are closed, and the upper cylinder 10U is in a resting state.

Here, according to the PSA device 50 of the present embodiment, the opening/closing valve (first opening/closing device) V12 located in the flow path (second flow path) L11 between the lower cylinder 10B and the easily adsorbable component storage tank 2 is It is located near the branch point P, and the volume of the path L11 from the inside of the on-off valve V12 to the branch point P is reduced. As a result, the amount of the mixed gas remaining in the path L11 from the inside of the on-off valve V12 to the branch point P in the adsorption process is reduced, so that the high-purity xenon derived from the lower cylinder 10B in the lower cylinder decompression process is transferred to the path L11. The mixed amount of impurities is reduced when passing through L4 and path L11. As a result, xenon, which is an easily adsorbable component, can be recovered in the easily adsorbable component storage tank 2 at high purity in the lower cylinder depressurization step.

(4) Upper cylinder decompression process Next, in the upper cylinder decompression process, the on-off valves V3, V7, V9, V11, V12, and V14 are closed, and the on-off valves V5 and V10 are opened. As a result, the gas in the upper cylinder 10U is introduced into the lower cylinder 10B due to the pressure difference between the upper cylinder 10U, which has been resting during the lower cylinder depressurization step, and the decompressed lower cylinder 10B. After purging the interior of the lower cylinder 10B, the gas introduced into the lower cylinder 10B is discharged from the lower cylinder 10B and recovered in the source gas storage tank 1 via the paths L10 and L17. The gas recovered in the raw material gas storage tank 1 is mixed with the raw material gas introduced from the path L1, and then used as the mixed gas in the adsorption step described above.

(5) Purge regeneration step Next, in the purge regeneration step, the on-off valves V3, V9, V12 and V14 are closed, and the on-off valves V5, V7 and V10 are opened. As a result, the nitrogen stored in the weakly adsorbable component storage tank 3 is introduced from above the upper tube 10U via the path L8 as a countercurrent purge gas. As the nitrogen introduced into the upper tube 10U moves downward in the upper tube 10U, the xenon adsorbed by the adsorbent is replaced and desorbed. The gas that is desorbed from the adsorbent and contains a relatively large amount of xenon is discharged from the upper tube 10U and then recovered in the source gas storage tank 1 via the lower tube 10B, the path L10 and the path L17. The gas recovered in the raw material gas storage tank 1 is mixed with the raw material gas introduced through the path L1 in the same manner as in the above-described upper cylinder decompression step, and then used as the mixed gas in the above-described adsorption step.
Instead of the nitrogen stored in the difficult-to-adsorb component storage tank 3, the nitrogen discharged from the upper tube 10U in the above-described adsorption step is used as the countercurrent purge gas, and is directly fed to the upper tube 10U in the purge regeneration step. may be introduced.

Here, according to the PSA device 50 of the present embodiment, the opening/closing valve (second opening/closing device) V10 located in the flow path (third flow path) L9 between the lower cylinder 10B and the source gas storage tank 1 branches. It is located near the point R, and the volume of the path L9 from the inside of the on-off valve V10 to the branch point R is reduced. As a result, the amount of xenon remaining in the path L9 from the inside of the on-off valve V10 to the branch point R is reduced in the upper cylinder decompression process and the purge regeneration process, so that the xenon concentration in the mixed gas is varied in the adsorption process. The mixed gas stored in the raw material gas storage tank 1 can be introduced into the lower cylinder 10 without removing the gas.

(6) Equalizing and pressurizing process Next, in the equalizing and pressurizing process, the on-off valves V3, V7, V8, V10, V12, V14, and V15 are closed, and the on-off valve V9 is opened. Here, when the equalizing pressure process is performed in the lower tube 10B and the upper tube 10U, the above-described rinsing process is performed in the lower tube 11B and the upper tube 11U. In the pressure equalizing and pressurizing process, nitrogen discharged from the upper cylinder 11U in which the rinsing process is being performed is introduced into the upper cylinder 10U and the lower cylinder 10B via the path L14.

When returning to the "adsorption process" from the "pressure equalization pressurization process" described above, the on-off valve V1 is opened and the on-off valve V2 is closed. Next, the mixed gas discharged from the raw material gas storage tank 1 is compressed by the compressor 4, and then introduced into the lower part of the lower cylinder 10B via the paths L15 and L4.

In the PSA device 50 of the present embodiment, the lower tube 11B and the upper tube 11U also sequentially perform the six steps described above, similarly to the lower tube 10B and the upper tube 10U.
Here, while the "adsorption step" to the "rinse step" are being performed in one adsorption cylinder (lower cylinder 10B and upper cylinder 10U), in the other adsorption cylinder (lower cylinder 11B and upper cylinder 11U), " Lower cylinder decompression process"-"purge regeneration process"-"equalization pressurization process" are carried out.
In addition, while the "lower cylinder depressurization process", the "purge regeneration process", and the "pressure equalization pressurization process" are being performed in one adsorption cylinder, the "adsorption process" to the "rinse process" are performed in the other adsorption cylinder. is done.

According to the PSA device 50 of the present embodiment, the six steps described above are sequentially repeated between the lower cylinder 10B and the upper cylinder 10U, and between the lower cylinder 11B and the upper cylinder 11U, thereby concentrating nitrogen and concentrating xenon. and can be performed continuously.

In the PSA device 50 of this embodiment, the raw material gas is introduced from the path L1 into the raw material gas storage tank 1, the nitrogen is discharged from the poorly adsorbed component storage tank 3 through the path L7, and the easily adsorbed component storage tank 2 through path L13 is continuously carried out regardless of the steps described above.

According to the PSA device 50 of the present embodiment, high-purity xenon can be separated and recovered from the source gas.
The purity of the xenon separated and recovered by the PSA device 50 of the present embodiment is not particularly limited, but is preferably 99% by volume or more, more preferably 99.9% by volume or more. Preferably, it is more preferably 99.95% by volume or more.

The PSA device 50 of this embodiment can be used as a part of manufacturing equipment for semiconductor products or display devices. According to the PSA apparatus 50 of the present embodiment, the exhaust gas discharged from the production facility is used as the raw material gas, and after the xenon contained in the raw material gas is separated and recovered, high-purity xenon can be supplied to the production facility.

Further, when the PSA apparatus 50 of the present embodiment is used as part of the manufacturing equipment described above, there are frequent situations in which there is no need to supply xenon, or in which raw material gas (that is, exhaust gas from the manufacturing equipment) does not flow. can occur. In such a case, in the PSA device 50 of the present embodiment, nitrogen discharged from the weakly adsorbable component storage tank 3 via the path L7 or xenon derived from the easily adsorbable component storage tank 2 via the path L13 is used as the raw material. By returning the product gas (xenon) to the gas storage tank 1, it is possible to stop the supply while maintaining a state in which the product gas (xenon) can always be supplied.

As described above, according to the PSA device 50 of the present embodiment, the on-off valve ( The first opening/closing device V12 is located near the branch point P. This reduces the volume of the path L11 from the inside of the on-off valve V12 to the branch point P, thereby reducing the amount of gas remaining in the path. Therefore, according to the PSA device 50 of the present embodiment, when the easily adsorbable component (gas) is led out from the lower cylinder 10B to the easily adsorbable component storage tank 2, impurities (components other than xenon in the raw material gas) are added to xenon. The amount of mixing is reduced, and high-purity xenon (easily adsorbable component) can be separated and recovered as a product.

Further, according to the PSA device 50 of the present embodiment, the branch point P located on the path L4 is located closer to the lower cylinder 10B. Thereby, the volume of the route L4 from the branch point P to the lower cylinder 10B can be reduced. Therefore, according to the PSA device 50 of the present embodiment, when the easily adsorbable component (gas) is led out from the lower cylinder 10B to the easily adsorbable component storage tank 2, the lower cylinder 10B, the path L4, the path L11 and the on-off valve V12 are blocked. It is possible to further reduce the amount of gas remaining in the path to be processed.

According to the PSA device 50 of the present embodiment, the opening/closing valve (second opening/closing device) V10 located in the path L9 constituting the flow path (third flow path) between the lower cylinder 10B and the source gas storage tank 1 is It is located near the branch point R. Also, the branch point R located on the path L4 is located near the lower cylinder 10B. As a result, when the mixed gas is discharged from the lower cylinder 10B to the source gas storage tank 1, the amount of gas remaining in the paths blocked by the lower cylinder 10B, the paths L4, L9, and the on-off valve V10 can be further reduced.

In the PSA device 50 of the present embodiment, the branch point P (branch point Q) located on the route L4 (L5) is the branch point R (branch point S ) is closer to the lower cylinder 10B (11B) than the lower cylinder 10B (11B). However, the configuration described above is an example, and the present invention is not limited to this. That is, in the PSA device 50 of the present embodiment, the positional relationship between the branch point P (branch point Q) and the branch point R (branch point S) on the route L4 (L5) may be reversed. Branching point P (branching point Q) and branching point R (branching point S) may be located at the same position by using a joint.

<Second embodiment>
Next, a PSA device as a second embodiment to which the present invention is applied will be described in detail with reference to FIG.
As shown in FIG. 2, the configuration of the PSA device 60 of the second embodiment differs from the configuration of the PSA device 50 of the first embodiment described above in that the path L9 shown in the first embodiment branches off to the path L4. Although it branches from the point R, it is different in that it has a path L9' that is directly connected to the lower cylinder 10B instead of the branch point R. Other configurations are the same as those of the first embodiment. be. Therefore, with regard to the PSA device 60 of the present embodiment, the same components as those of the PSA device 50 of the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

One end of the path L9' is connected to the lower tube 10B, and the other end joins the paths L10' and L17'. That is, the path L9' is located between the lower tube 10B and the path L17' and is part of the flow path (third flow path) for returning the gas from the lower tube 10B to the source gas storage tank 1.
One end of the path L10' is connected to the lower tube 11B, and the other end joins the paths L9' and L17'. That is, the path L10' is located between the lower tube 11B and the path L17' and is part of a flow path (third flow path) for returning the gas from the lower tube 11B to the source gas storage tank 1.

One end of the path L17' branches into a path L9' and a path L10', and the other end is connected to the source gas storage tank 1. That is, the path L17' is located between the lower cylinders 10B, 11B and the raw material gas storage tank 1, and is a flow path (third flow path) for returning the gas from the lower cylinders 10B, 11B to the raw material gas storage tank 1. is part of

In the PSA device 60 of the present embodiment, among these on-off valves, the on-off valve (second opening/closing device) V10 located on the path L9' is preferably located closer to the lower cylinder 10B.

Here, the position of the on-off valve V10 closer to the lower cylinder 10B means that the distance between the on-off valve V10 and the lower cylinder 10B is short. As a result, the volume in the path L9' between the on-off valve V10 and the lower cylinder 10B can be reduced. That is, when the gas discharged from the lower cylinder 10B is discharged to the source gas storage tank 1, the amount of gas remaining in the path L9' between the on-off valve V10 and the lower cylinder 10B can be reduced.

The amount of gas remaining in the path L9' from the on-off valve V10 to the lower cylinder 10B (residual gas amount) is determined by the volume of the piping forming the path L9' from the on-off valve V10 to the lower cylinder 10B, It is the total sum with the volume inside the valve V10.
In the PSA device 60 of this embodiment, the volume of the path L9′ from the inside of the on-off valve V10 to the lower cylinder 10B is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute. .

Similarly, in the PSA device 60 of the present embodiment, among these on-off valves, the on-off valve (second opening/closing device) V11 positioned on the path L10' is preferably positioned closer to the lower cylinder 11B.

Here, the position of the on-off valve V11 closer to the lower cylinder 11B means that the distance between the on-off valve V11 and the lower cylinder 11B is short. As a result, the volume in the path L10' between the on-off valve V11 and the lower cylinder 11B can be reduced. That is, when the gas discharged from the lower cylinder 11B is discharged to the source gas storage tank 1, the amount of gas remaining in the path L10' between the on-off valve V11 and the lower cylinder 11B can be reduced.

The amount of gas remaining in the path L10′ from the on-off valve V11 to the lower cylinder 11B (residual gas amount) is determined by the volume of the piping forming the path L10′ from the on-off valve V11 to the lower cylinder 11B, and the opening/closing volume. It is the total sum with the internal volume of the valve V11.
In the PSA device 60 of the present embodiment, the volume of the path L10' from the inside of the on-off valve V11 to the lower cylinder 11B is preferably 0.1% by volume or less of the gas volume sucked by the compressor 4 per minute. .

As described above, according to the PSA device 60 of this embodiment, the same effects as those of the PSA device 50 of the first embodiment described above can be obtained.
Furthermore, according to the PSA device 60 of the present embodiment, the path L9' directly connected to the lower cylinder 10B is provided, and the on-off valve V10 is provided near the lower cylinder 10B, thereby further reducing the amount of gas remaining in the path. It has the effect of being able to

It should be noted that the technical scope of the present invention is not limited to the above-described embodiments, and includes designs and the like that do not deviate from the gist of the present invention.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited by the following description.

Using the PSA apparatus 50 shown in FIG. 1, the opening and closing valves were controlled as shown in Table 1 below to separate and recover the product gas from the raw material gas.
The configuration of the PSA device 50 was as follows.
・Lower cylinders (10B, 11B), upper cylinders (10U, 11U): stainless steel 80A (inner diameter 83.1 mm), adsorbent filling height 500 mm
・ Adsorbent: activated carbon (manufactured by Osaka Gas Chemicals Co., Ltd.), each filled with 1.5 kg ・ Compressor 4: Diaphragm compressor (manufactured by KNF, discharge rate: 20 L / min)
- Compressor 5: Diaphragm compressor (manufactured by KNF, discharge rate: 0.2 L / min)
(All below are at 0°C and atmospheric pressure)
- Raw material gas: xenon (Xe) + nitrogen - Introduction amount of raw material gas from path L1 to raw material gas storage tank 1: 2.0 L/min
・Easily adsorbable component: xenon ・Amount drawn from easily adsorbable component storage tank 2 to path L13: 0.2 L/min
・Poorly adsorbable component: Nitrogen ・Amount of poorly adsorbable component discharged from storage tank 3 to path L7: 1.8 L/min

<Example 1>
Diaphragm-type two-way valves (metal diaphragm valves manufactured by Fujikin; FPR-ND-71-9.52) were used as the on-off valves V10, V11, V12, and V13, and were operated under the conditions shown in Table 1 above.
The results are shown in Table 2 below.
In addition, the total volume including the pipe volume of the path L11 between the on-off valve V12 and the branch point P and the volume inside the on-off valve V12 was 19 mL.
In addition, the total volume obtained by adding the pipe volume of the route L12 between the on-off valve V13 and the branch point Q and the volume inside the on-off valve V13, the pipe volume of the route L9 between the on-off valve V10 and the point R, The total volume including the volume inside the on-off valve V10 and the total volume including the volume inside the on-off valve V11 and the pipe volume of the path L10 between the on-off valve V11 and the branch point S are both 19 mL. there were.

As shown in Table 2, according to the pressure swing adsorption gas separation apparatus of the present invention, it was found that easily adsorbable components can be separated with high purity. In particular, when the easily adsorbable component concentration in the source gas storage tank was 60% or more, the easily adsorbable component (xenon) could be separated with a high purity of 99% by volume or more.

<Comparative Example 1>
As a comparative example of the present invention, a separation experiment was conducted in the same manner as in Example 1 using the device of the prior art (FIG. 1 shown in Patent Document 1 mentioned above).
The total volume, which is the sum of the pipe volume in each route and the volume inside the on-off valve, was 53 mL.
The results are shown in Table 3 below.

As shown in Table 3, in the device of the prior art, the total volume, which is the sum of the pipe volume in each path and the volume inside the on-off valve, is 53 mL. %.

<Example 2>
As the on-off valves V10, V11, V12, and V13, diaphragm-type three-way diverting valves (manufactured by Fujikin, metal diaphragm valve: FPR-NDTB-71-9.52) were used and operated under the conditions shown in Table 1 above.
The results are shown in Table 4 below.
In addition, the total volume including the pipe volume of the path L11 between the on-off valve V12 and the branch point P and the volume inside the on-off valve V12 was 5 mL.
In addition, the total volume obtained by adding the pipe volume of the route L12 between the on-off valve V13 and the branch point Q and the volume inside the on-off valve V13, the pipe volume of the route L9 between the on-off valve V10 and the point R, The total volume including the volume inside the on-off valve V10 and the total volume including the volume inside the on-off valve V11 and the pipe volume of the path L10 between the on-off valve V11 and the branch point S are both 5 mL. there were.

As shown in Table 4, according to the present invention, it was found that by setting the total volume of each of the piping portions where the gas components remain to 5 mL, the readily adsorbable components can be separated with even higher purity. In particular, when the easily adsorbable component concentration in the source gas storage tank was 60% or more, the easily adsorbable component (xenon) could be separated with a high purity of 99.95% by volume or more.

<Example 3>
Three-way ball valves (SS-63XLTS8-A30S4 manufactured by Swagelok) were used as the on-off valves V10, V11, V12, and V13, and operated under the conditions shown in Table 1 above.
The results are shown in Table 5 below.
In addition, the total volume including the pipe volume of the path L11 between the on-off valve V12 and the branch point P and the volume inside the on-off valve V12 was 5 mL.
In addition, the total volume obtained by adding the pipe volume of the route L12 between the on-off valve V13 and the branch point Q and the volume inside the on-off valve V13, the pipe volume of the route L9 between the on-off valve V10 and the point R, The total volume including the volume inside the on-off valve V10 and the total volume including the volume inside the on-off valve V11 and the pipe volume of the path L10 between the on-off valve V11 and the branch point S are both 5 mL. there were.

As shown in Table 5, according to the present invention, even when a three-way ball valve is used as the on-off valve, by setting the total volume of the pipe portions where the gas components remain to 5 mL each, the readily adsorbable components can be easily adsorbed. It was found that the separation was possible with a purity as high as in Example 2. That is, when the easily adsorbable component concentration in the source gas storage tank was 60% or more, the easily adsorbable component (xenon) could be separated with a high purity of 99.95% by volume or more.

<Example 4>
The operation was performed under the same conditions as in Example 2, except that argon was used instead of nitrogen as the weakly adsorbable component contained in the source gas.
The results are shown in Table 6 below.

As shown in Table 6, according to the present invention, even when argon is used as the weakly adsorbable component, the total volume of the pipe sections where gas components remain is set to 5 mL for each of the easily adsorbable components. It was found that the separation was possible with a purity as high as in Example 2. That is, when the easily adsorbable component concentration in the source gas storage tank was 60% or more, the easily adsorbable component (xenon) could be separated with a high purity of 99.95% by volume or more.

<Comparative Example 2>
The operation was performed under the same conditions as in Comparative Example 1, except that argon was used instead of nitrogen as the weakly adsorbable component contained in the source gas.
The results are shown in Table 7 below.

As shown in Table 7, even when argon is used instead of nitrogen as the difficult-to-adsorb component contained in the raw material gas, in the prior art device, the pipe volume in each path and the volume inside the on-off valve are Since the total volume added was 53 mL, the concentrations of easily adsorbable components (xenon) were all less than 99% by volume.

REFERENCE SIGNS LIST 1 raw material gas storage tank 2 easily adsorbable component storage tank 3 poorly adsorbable component storage tank 4, 5 compressors 10B, 11B lower cylinders 10U, 11U upper cylinders 50, 60 Pressure fluctuation adsorption type gas separation device (PSA device)
V1 to V15・・・On-off valve (open-close device)
L1 to L17 ... route (flow path)
P, Q, R, S, T... branch point

Claims (8)

An apparatus for separating and recovering two or more components from a raw material gas using a pressure swing adsorption gas separation method,
one or more adsorption cylinders filled with an adsorbent that easily adsorbs one or more of the components and has poor adsorption of the other components;
a source gas storage tank for storing the source gas;
an easily adsorbable component storage tank for storing the easily adsorbable component led out from the adsorption cylinder ;
a compressor that compresses the gas drawn out from the source gas storage tank or the easily adsorbable component storage tank and supplies the gas to the adsorption column;
a first flow path positioned between the compressor and the adsorption column ;
a second flow path branched from the first flow path at a first branch point and positioned between the first branch point and the easily adsorbable component storage tank;
a first opening/closing device positioned in the second flow path ;
a third flow path branched from the first flow path at a second branch point and located between the second branch point and the source gas storage tank;
a second opening and closing device located in the third flow path,
The first opening/closing device is positioned at a location where the volume of the path from the inside of the first opening/closing device to the first branch point is 0.1% by volume or less of the gas volume sucked by the compressor in one minute. death,
The second opening/closing device is positioned at a location where the volume of the path from the inside of the second opening/closing device to the second branch point is 0.1% by volume or less of the gas volume sucked by the compressor per minute. A pressure swing adsorption gas separator. The first branch point is located where the volume of the first flow path between the first branch point and the adsorption cylinder is 1% by volume or less of the gas volume sucked by the compressor in one minute. The pressure swing adsorption gas separation apparatus according to claim 1, wherein The second branch point is located where the volume of the first flow path between the second branch point and the adsorption cylinder is 1% by volume or less of the volume of gas sucked by the compressor per minute. The pressure swing adsorption gas separation apparatus according to claim 2, wherein An apparatus for separating and recovering two or more components from a raw material gas using a pressure swing adsorption gas separation method,
one or more adsorption cylinders filled with an adsorbent that easily adsorbs one or more of the components and has poor adsorption of the other components;
a source gas storage tank for storing the source gas;
an easily adsorbable component storage tank for storing the easily adsorbable component led out from the adsorption cylinder;
a compressor that compresses the gas drawn out from the source gas storage tank or the easily adsorbable component storage tank and supplies the gas to the adsorption column;
a first flow path positioned between the compressor and the adsorption cylinder;
a second flow path branched from the first flow path at a first branch point and positioned between the first branch point and the easily adsorbable component storage tank;
a first opening/closing device positioned in the second flow path;
a third flow path connecting the adsorption cylinder and the source gas storage tank,
one end of the third channel is directly connected to the adsorption cylinder,
The first opening/closing device is positioned at a location where the volume of the path from the inside of the first opening/closing device to the first branch point is 0.1% by volume or less of the gas volume sucked by the compressor in one minute. A pressure swing adsorption gas separator. The first branch point is located where the volume of the first flow path between the first branch point and the adsorption cylinder is 1% by volume or less of the gas volume sucked by the compressor in one minute. The pressure swing adsorption gas separation apparatus according to claim 4, wherein An apparatus for separating and recovering two or more components from a raw material gas using a pressure swing adsorption gas separation method,
one or more adsorption cylinders filled with an adsorbent that easily adsorbs one or more of the components and has poor adsorption of the other components;
a source gas storage tank for storing the source gas;
an easily adsorbable component storage tank for storing the easily adsorbable component led out from the adsorption cylinder;
a compressor that compresses the gas drawn out from the source gas storage tank or the easily adsorbable component storage tank and supplies the gas to the adsorption column;
a first flow path positioned between the compressor and the adsorption cylinder;
a second flow path branched from the first flow path at a first branch point and positioned between the first branch point and the easily adsorbable component storage tank;
a first opening/closing device positioned in the second flow path;
a third flow path branched from the first flow path at a second branch point and positioned between the second branch point and the source gas storage tank;
The first opening/closing device is positioned at a location where the volume of the path from the inside of the first opening/closing device to the first branch point is 0.1% by volume or less of the gas volume sucked by the compressor in one minute. death,
The pressure swing adsorption gas separation device, wherein the first branch point is closer to the adsorption column than the second branch point. The first branch point is located where the volume of the first flow path between the first branch point and the adsorption cylinder is 1% by volume or less of the gas volume sucked by the compressor in one minute. The pressure swing adsorption gas separation apparatus according to claim 6, wherein The second branch point is located where the volume of the first flow path between the second branch point and the adsorption cylinder is 1% by volume or less of the volume of gas sucked by the compressor per minute. The pressure swing adsorption gas separation apparatus according to claim 7, wherein

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