JP5864994B2 - Gas separation apparatus and method - Google Patents

Description

  The present invention relates to a gas separation apparatus and method.

  The gas separation device of Patent Document 1 is equipped with a plurality of nitrogen gas generators including a compressor and a PSA, and controls the number of operating nitrogen gas generators according to fluctuations in product gas usage, thereby saving energy. Has been implemented. The gas separation device of Patent Document 2 saves energy by controlling the number of rotations of the motor of the compressor in accordance with fluctuations in the amount of product gas used.

Japanese Patent No. 4002852 JP 2002-45635 A

  The gas separation device of Patent Document 1 controls the number of operating nitrogen gas generators in accordance with fluctuations in the amount of product gas used, regardless of which stage of the nitrogen gas production cycle time is in. Further, the gas separation device of Patent Document 2 also controls the number of revolutions of the motor in accordance with the amount of product gas used, regardless of the stage of the nitrogen gas generation cycle time. However, in order to maintain the purity and pressure of the product gas, a high pressure is required especially at the beginning of the cycle time, but when the amount of product gas used is small, the number of operating nitrogen gas generators can be reduced, or the motor If you slow down, the purity and pressure of the product gas will decrease.

  In view of the above problems, the present invention controls the number of operating compressors in accordance with the amount of product gas used in consideration of which stage of the cycle time, while maintaining product gas purity and pressure, An object of the present invention is to provide a gas separation device and method that enable energy-saving operation by controlling the number of operating compressors according to the amount of product gas used.

In order to solve the above-described problems, the present invention controls a plurality of compressors that compress air, an adsorption tank that adsorbs a part of the air compressed by the compressor, and the operation of the compressor. A controller that performs an adsorption process of supplying compressed air to the adsorption tank to adsorb one gas, and an extraction process of taking out another gas as a product gas from the adsorption tank; at the start, it is operated compressor of the total number, and reduce the number of operating the compressor when the amount of product gas is reduced,
The gas separation device is characterized in that the number of operating units to be reduced is changed according to the amount of use .

Further, the present invention includes a compression step of compressing air by a plurality of compressors, an adsorption step of adsorbing a part of the air compressed by the compressor from the air compressed by the compression step to an adsorption tank, And taking out another gas from the adsorption tank as a product gas. In the compression step, when the amount of product gas used is reduced by operating all the compressors at the start of the adsorption step, the compressor to reduce the number of operation,
A gas separation method is provided, wherein the number of operating units to be reduced is changed according to the amount of use .

  ADVANTAGE OF THE INVENTION According to this invention, the gas separation apparatus and method which enable the energy saving operation according to the usage-amount of product gas can be provided, maintaining product gas concentration and pressure.

1 is a schematic configuration diagram of a gas separation device according to Embodiment 1 of the present invention. The graph which shows the pressure change of the gas separation apparatus which concerns on Example 1 of this invention. FIG. 1 is a control flow diagram (whole) of a gas separation device according to a first embodiment of the present invention. Control flow diagram (discriminating process) of the gas separation device according to the first embodiment of the present invention The figure which shows the energy-saving effect of the gas separation apparatus which concerns on Example 1 of this invention.

  Embodiments according to the present invention will be described below with reference to the drawings.

  The present invention will be described with reference to FIGS.

  A gas separation device 1 shown in FIG. 1 is a PSA type gas separation device. The gas separation device 1 includes an air supply unit 2 that supplies air and a PSA unit 3 that generates product gas. This air supply unit 2 removes impurities while recovering the drain water that is collected, and a compressor 4 that compresses air, an air tank (air storage tank) 5 that stores compressed air, a dryer 6 that dehumidifies compressed air, and A drain filter 7 is provided. In the present embodiment, as an example, the compressor 4, the air tank 5, the dryer 6, and the drain filter 7 are stored in a casing. On the other hand, the PSA unit 3 separates a predetermined gas from the compressed air supplied from the air supply unit 2, thereby generating a product gas, and a nitrogen tank (product gas) for storing the product gas (nitrogen). Storage tank) 41.

  The compressed air stored in the air tank 5 is supplied to an adsorption tank 19 described later, and a predetermined gas is separated from the compressed air stored in the air tank 5. In this embodiment, a case where nitrogen is separated by adsorbing oxygen in the adsorption tank 19 will be described. However, oxygen may be separated by adsorbing nitrogen, or other gases may be separated from compressed air other than the atmosphere. May be separated.

  As the compressor 4, a reciprocating type, screw type or scroll type compressor, a so-called booster compressor which is supplied with primary pressure from the outside and recompresses, etc. are used, and a plurality of them are mounted. . This embodiment will be described assuming that three or four are mounted.

  A pipe 16 for flowing compressed air from the air tank 5 is connected to the air tank 5, and a pipe 17 branched in two lines is connected to a terminal position of the pipe 16. A supply valve 18 for opening and closing the flow path is provided in the pipe 17 in the middle, and an adsorption tank 19 for adsorbing oxygen molecules and taking out nitrogen gas as product gas is connected to the terminal. This adsorption tank has a constant volume. Further, pipes 21 are connected to the pipes 17 at positions between the supply valve 18 and the adsorption tank 19, respectively, and an exhaust valve 22 that opens and closes the flow path on the way is connected to the pipes 21 for noise reduction. An exhaust silencer 23 with a filter is provided. This exhaust silencer may be provided for each adsorption tank 19. Further, a pipe 25 is connected to the pipe 17 so as to connect a position between the pipe 21 and the adsorption tank 19, and a lower pressure equalizing valve 26 for opening and closing the flow path is provided in the pipe 25. .

  For example, the adsorption tank 19 is filled with an adsorbent which is an adsorbing means for adsorbing oxygen molecules. Specifically, molecular sieve carbon or zeolite is used as the adsorbent. Pipes 31 that merge with each other at the terminal position are respectively connected to the adsorption tank 19. These pipes 31 are connected with pipes 32 so as to connect the adsorption tanks 19 to each other, and the pipes 32 are provided with a throttle 33. A pipe 35 is connected to the pipe 31 so as to connect the opposite sides of the adsorption tank 19 with respect to the pipe 32. The pipe 35 is provided with an upper pressure equalizing valve 36 for opening and closing the flow path. ing. The pipes 31 are each provided with an extraction valve 38 for opening and closing the flow path on the opposite side of the adsorption tank 19 from the respective pipes 35. A pipe 40 is connected to the joining position of the pipe 31, and a nitrogen tank 41 as a product gas storage tank for storing nitrogen gas is connected to a terminal position of the pipe 40. The nitrogen tank 41 is connected to a pipe 43 whose terminal position is the discharge port 42. In the middle of the pipe 43, dust and the like are sequentially removed from the nitrogen tank 41 side, and the gas flow rate is adjusted. There are provided a filter regulator 44, a discharge valve 45 for opening and closing the flow path, and a flow rate adjusting valve 46 for adjusting the flow rate of gas. A pipe 48 and a pipe 49 are connected between the filter regulator 44 and the discharge valve 45 of the pipe 43. The pipe 48 has an opening / closing valve 50 for opening and closing the flow path in order from the pipe 43 side, A flow rate adjusting valve 51 for adjusting the flow rate and a silencer 52 are provided. The pipe 49 is provided with an open / close valve 54 that opens and closes the flow path, a flow rate adjustment valve 55 that adjusts the flow rate of gas, and an oxygen sensor 56 that detects the oxygen concentration in order from the pipe 43 side. The oxygen sensor 56 is communicably connected to the control unit 60 and outputs a detection signal to the control unit 60. The flow rate sensor 57 that detects the product gas usage amount Qu is installed in front of the discharge port 42 and is connected to the control unit 60 so that the detection signal can be communicated. Furthermore, the pressure sensor 58 for detecting the pressure of the nitrogen gas is connected to the nitrogen tank 41 and connected to the control unit 60 so that the detection signal can be communicated.

  The supply valve 18, the exhaust valve 22, the lower pressure equalizing valve 26, the upper pressure equalizing valve 36, the take-off valve 38, the discharge valve 45, the flow rate adjusting valve 46, the on / off valve 50, the flow rate adjusting valve 51, and the on / off valve 54 are connected to the control unit 60. It is connected so as to be communicable and operates in response to a command from the control unit 60.

  The oxygen sensor 56, the flow rate sensor 57, and the pressure sensor 58 described above may be connected to the buffer tank 70 and the discharge port 71 installed outside.

  Up to now, the configuration of the gas separation device 1 has been described. Here, a gas separation method performed in the gas separation device will be described.

  In the gas separation device 1, the compression process of compressing air by the compressor 4, the storage process of storing the air compressed by the compression process in the air tank 5, the dehumidification process of dehumidifying the compressed air by the air dryer 6, and dehumidification by the dehumidification process A separation process for separating the gas from the air is performed.

  In the separation step of the gas separation device 1, the following steps (a) to (d) are sequentially repeated.

  (A) Adsorption step: Compressed air compressed by the compressor 4 and stored in the air tank 5 is introduced into the adsorption tank 19 filled with the adsorbent by opening the supply valve 18 and is introduced into the nitrogen tank 41. The step of refluxing the remaining nitrogen gas to the adsorption tank 19 by opening the extraction valve 38 to increase the pressure inside the adsorption tank 19 and adsorbing oxygen molecules to the adsorbent using the pressure.

  (B) Extraction process: Continuing from the adsorption process, the compressed air is continuously introduced from the air tank 5 into the adsorption tank 19, and at the same time, the nitrogen gas separated and generated by the adsorbent is extracted from the adsorption tank 19 and stored in the nitrogen tank 41. Process.

  (C) Pressure equalization step: The upper pressure equalization valve 36 and the lower pressure equalization valve 26 are opened and closed to equalize the pressure in the pair of adsorption tanks 19 after completion of the take-out step, thereby increasing the adsorption efficiency of the next adsorption step and increasing the purity. For generating nitrogen gas. In addition, although the case where there are a plurality of adsorption tanks 19 has been described here, the number of adsorption tanks 19 may be one, and in that case, the pressure equalization step is unnecessary.

  (D) Regeneration step: A step of regenerating the adsorbent by desorbing oxygen molecules adsorbed by the adsorbent through the pipe 21 by opening the exhaust valve 22 in the adsorption tank 19 after completion of the pressure equalization step. . In this regeneration step, the supply valve 18, the lower pressure equalizing valve 26, the upper pressure equalizing valve 36 and the take-off valve 38 related to the adsorption tank 19 other than the exhaust valve 22 are closed.

  In addition, when there are a plurality of adsorption tanks 19, while the adsorption process / removal process (process (a) (b)) is performed in a certain adsorption tank 19, the regeneration process (process (d (d)) is performed in another adsorption tank 19. )) Is performed. Then, (c) pressure equalization process is performed simultaneously, the adsorption tank 19 is replaced, and an adsorption process and an extraction process (process (a) (b)) and a regeneration process (process (d)) are performed.

  (C) In the pressure equalization process, (d) the pressure in the adsorption tank 19 is used to equalize the adsorption tank evacuated in the regeneration process with the adsorption tank pressurized in the adsorption process / removal process (process (a) (b)). Becomes lower than the pressure required for adsorbing oxygen gas in the adsorption step and the extraction step (steps (a) and (b)). Even when there is only one adsorption tank 19, the pressure at the start of the adsorption process is atmospheric pressure because it is a regeneration process (process (d)) immediately before the adsorption process / removal process (process (a) (b)). . Accordingly, at the start of the adsorption process / removal process (process (a) (b)), the pressure is low for adsorbing oxygen molecules in the adsorption tank 19, so this embodiment is used to maintain the purity and pressure of nitrogen gas. Then, at the start of the adsorption process, all the compressors 4 are operated.

In the gas separation device 1, the plurality of compressors 4 are controlled by the control unit 60, and the separation process is performed as described above. In normal operation, a compressor unit equipped with multiple compressors 4 is equipped with multiple units (n units) to maintain the performance of the rated generation amount Qm at the start of the adsorption process (at the start of the cycle time). All the compressors in operation are operated, and the separation process time selected in advance (process (a) (b) (c) (d)): each of the gas separation methods described above at the basic cycle time Ti. Product gas is generated by stepping and repeating the process. (The total time of the adsorption process and the extraction process (process (a) (b)) at that time is expressed in t seconds.)
Here, a method for controlling the number of operating compressors 4 in accordance with the amount of product gas used will be described with reference to the graph shown in FIG. 2 and the flows shown in FIGS.

  First, as shown in FIG. All (n) compressors 4 are operated, and the PSA unit 3 is operated at the basic cycle time T.

  Next, the product gas usage Qu is detected by the flow sensor 57, and the number of compressors 4 and the cycle time T are controlled according to the product gas usage Qu. This control will be described below.

  In the present embodiment, the ratio Rq of the usage amount to the rated generation amount Qm, which is the amount of compressed air supplied when all the plurality of compressors 4 are operated, is the usage ratio Rq = 100 · Qu / Qm, (0% <Rq <100%). This usage ratio Rq is obtained from the rated generation quantity Qm and the product gas usage quantity Qu.

  For example, if the usage amount of the product gas actually used is Qu = 250 L / min with respect to the rated generation amount Qm = 500 L / min, the usage ratio Rq = 100 · Qu / Qm = 50. In other words, it can be judged that only 50% of the rated amount is used.

  Next, the classification determination process of the usage rate ratio Rq is performed as follows.

  The number of compressors installed in the air supply unit of this equipment is n.

The number of units stopped by unit control is represented by i units. (Basically, i = 0,1,2, ... n to stop one unit at a time)
The actual number of units in operation is represented by ni units (i = 0,1,2, ... n).

For example, it is assumed that n = 3.
When i = 0, ni = 3
When i = 1, the actual number of operating units is ni = 2
When i = 2, the actual operating number is ni = 1
When i = 3, the actual number of units operated is ni = 0.

  Energy saving operation is performed by reducing the number of operating units and extending the cycle time while maintaining the performance, depending on which category the product gas usage Qu is between 0% and 100%. By extending the cycle time, the purity and pressure of nitrogen gas can be maintained even if the amount of raw material air supplied is reduced while reducing power consumption.

  Since the amount of raw material air supplied from one compressor is large, the product gas concentration and pressure cannot be maintained if a plurality of compressors are stopped at a time. Therefore, in this embodiment, in order to maintain the rated performance, a method of stopping one unit at a time while looking at the product gas usage Qu from the operating state of all the compressors is adopted.

  First, equally divide by the number of installed units n, and let Ri be the ratio of the amount of air generated when operating with n-i units to the rated generation rate Qm. Ri is 100 · (n−i) / n where the rated generation amount Qm is 100%.

For example, when the number of installed devices is n = 3 (i = 0,1,2,3)
When i = 0, R0 = 100 ・ (3-0) / 3 = 100%
When i = 1, R1 = 100 ・ (3-1) / 3 = 66%
When i = 2, R2 = 100 ・ (3-2) / 3 = 33%
When i = 3, R3 = 100 · (3-3) / 3 = 0%.

For example, when the number of installed units is n = 4 (the number of stopped units is i = 0,1,2,3,4)
When i = 0, R0 = 100 ・ (4-0) / 4 = 100%
When i = 1, R1 = 100 ・ (4-1) / 4 = 75%
When i = 2, R2 = 100 ・ (4-2) / 4 = 50%
When i = 3, R3 = 100 ・ (4-3) / 4 = 25%
When i = 4, R4 = 100 · (4-4) / 4 = 0%.

  Here, after determining which division with respect to Ri the usage ratio Rq = 100 · Qu / Qm is (category discrimination processing), the number of operating units and the increase / decrease in cycle time are controlled stepwise.

  For example, when n = 3, the usage ratio Rq = 100 · Qu / Qm is 3 in [R0 <Ri <R1], [R1 <Ri <R2], and [R2 <Ri <R3] corresponding to Ri. Divide into categories, and increase / decrease in the number of operating units and cycle time are controlled step by step depending on which category.

  In addition, when n = 4, the usage ratio Rq = 100 · Qu / Qm is set to [R0 <Ri <R1], [R1 <Ri <R2], [R2 <Ri <R3], [ R3 <Ri <R4] is divided into 4 categories, and the number of operating units and cycle time increase / decrease are controlled step by step depending on which category.

  The stepwise operation at this time is STEPi (i = 0, 1, 2,... N) and is shown in FIG. Moreover, the graph of FIG. 2 shows the pressure change of each part of the gas separation apparatus 1 according to the change of the operation number of the compressors 4 and the cycle time T at this time.

  The number of compressors in the air supply unit is n. At the start of the adsorption process (start of cycle time), operation is performed with all n units in order to maintain performance (STEP 0). When the product gas consumption Qu decreases from the rated generation amount Qm, it is determined whether the usage ratio Rq falls within the range category for Ri, and the number of operating units is stopped one step at a time (STEPi ). With the remaining number of operating units stopped, the operation is extended from the adsorption process / removal process (process (a) (b)) time Ti seconds.

  In order to generate the rated generation amount Qm, n compressors are operated, and the adsorption process and extraction process (process (a) (b)) time of the basic cycle time selected in advance is set to t seconds. The time of adsorption process / removal process (process (a) (b)) that changes with the number of operating units is Ti = t · (n−i) / n.

  For example, a case where the number of compressors mounted n = 3 will be described.

  When the usage ratio Rq is in the range [R0 <Ri <R1] (100% to 66% range), normal operation is performed with the basic cycle time. As “STEP0”, three compressors are operated, the adsorption process / the extraction process (process (a) (b)) is performed for t seconds, the process (c) (d) is performed, and this is repeated.

  When the usage ratio Rq is in the range [R1 <Ri <R2] (in the range of 66% to 33%), the three compressors are operated as “STEP0” in the same way as normal operation, and the adsorption process / removal process (process) Perform (a) and (b)) for t seconds, and then stop one compressor as “STEP1” and operate a total of two compressors, and extend the adsorption process and extraction process for 2/3 tsec. . Thereafter, similarly to the normal operation, steps (c) and (d) are performed, three compressors are operated, and “STEP 0” and subsequent steps are repeated.

  When the usage ratio Rq is in the range [R2 <Ri <R3] (range of 33% to 0%), three compressors are operated as “STEP0” in the same way as normal operation, and the adsorption process / removal process (process) Perform (a) and (b)) for t seconds, and then stop the compressor as “STEP1” and operate a total of two compressors, extending the adsorption process and the extraction process for 2/3 tsec. . Furthermore, as “STEP 2”, one compressor is stopped and the remaining one is operated, and the adsorption process and the extraction process are further extended by 1/3 tsec. Thereafter, similarly to the normal operation, steps (c) and (d) are performed, three compressors are operated, and “STEP 0” and subsequent steps are repeated.

  For example, a case where the number of compressors mounted n = 4 will be described.

  When the usage ratio Rq is in the range [R0 <Ri <R1] (100% to 75% range), normal operation is performed with the basic cycle time. As "STEP0", four compressors are operated, the adsorption process / the extraction process (process (a) (b)) is performed for t seconds, the process (c) (d) is performed, and this is repeated.

  When the usage ratio Rq is in the range [R1 <Ri <R2] (in the range of 75% to 50%), the four compressors are operated as “STEP0” in the same way as the normal operation, and the adsorption process / removal process (process) Perform (a) and (b)) for t seconds, and then stop the compressor as “STEP1” and operate a total of three compressors, extending the adsorption process and the extraction process for 3/4 tsec. . Thereafter, similarly to the normal operation, steps (c) and (d) are performed, four compressors are operated, and “STEP 0” and subsequent steps are repeated.

  When the usage ratio Rq is in the range [R2 <Ri <R3] (in the range of 50% to 25%), the four compressors are operated as “STEP0” as in normal operation, and the adsorption process / removal process (process) (a) and (b)) are performed for t seconds, and then one compressor is stopped as “STEP 1” and a total of three compressors are operated, and the adsorption process and the extraction process are extended by 3/4 t seconds. . Furthermore, as "STEP2", one compressor is stopped and a total of two compressors are operated, and the adsorption process and extraction process are extended for 1/2 tsec. Thereafter, similarly to the normal operation, steps (c) and (d) are performed, four compressors are operated, and “STEP 0” and subsequent steps are repeated.

  When the usage ratio Rq is in the range [R3 <Ri <R4] (25% to 0% range), the four compressors are operated as “STEP0” in the same way as normal operation, and the adsorption process / removal process (process) Perform (a) and (b)) for t seconds, and then stop the compressor as “STEP1” and operate a total of three compressors, extending the adsorption process and the extraction process for 3/4 tsec. . Furthermore, as "STEP2", one compressor is stopped and a total of two compressors are operated, and the adsorption process and extraction process are extended for 1/2 tsec. Furthermore, as "STEP3", one compressor is stopped and the remaining one is operated, and the adsorption process and extraction process are extended by 1/4 tsec. Thereafter, similarly to the normal operation, steps (c) and (d) are performed, four compressors are operated, and “STEP 0” and subsequent steps are repeated.

  In the middle of the above energy-saving operation, if the product gas consumption Qu suddenly increases or the nitrogen gas purity suddenly deteriorates (oxygen concentration increases), the performance is maintained or recovered. Therefore, the adsorption process and the extraction process (process (a) (b)) are stopped instantaneously, the pressure equalization process (c) is performed, and the operation of switching to the next adsorption tank is performed. All the compressors 4 are operated, and the normal operation is returned to the basic cycle time. That is, during the above energy-saving operation, when the product gas usage Qu exceeds the specified value or the oxygen concentration exceeds the specified value, the operation is started with all the compressors 4. Become. The pressure change rate Rp = Pdt (slope) or the residual oxygen concentration change rate Rd = Ddt (slope) is determined by the pressure sensor 58 that detects the pressure of the product gas or the oxygen sensor 56 that detects the concentration of the product gas. Thus, the above control may be performed when these values exceed a specified value.

  The effect of energy saving in the present embodiment will be described with reference to FIG. For example, in FIG. 4, in a gas separation apparatus equipped with three compressors 4, the power consumption when the number control of this embodiment is applied is the power consumption when the number control of this embodiment is not applied (comparative example). Shown in comparison. As shown in FIG. 4, according to the present embodiment, the power consumption of the product gas can be reduced to 60% when the usage amount of the product gas is 0 to 33% with respect to the comparative example. % Power consumption, and an energy saving effect corresponding to the area indicated by the hatched portion in the graph of FIG. 4 can be obtained.

  According to the present embodiment, since all the compressors 4 are operated at the start of the cycle time, it is possible to perform an energy saving operation while maintaining the concentration and pressure of the product gas.

  In the gas separation device according to the first embodiment, when the compressor 4 fails, the mode can be selected to stop the device completely or to continue operating the gas separation device with another compressor 4 that does not fail.

  When “normal mode” is selected, if even one compressor is stopped due to a failure, the gas separation device is completely stopped. When “Emergency Mode” is selected, the gas separation device is continuously operated by another normal compressor, and the operation is continued even when the performance (concentration, pressure, flow rate) of the product gas is not satisfied.

  According to this embodiment, when the compressor 4 fails, the operation is continued even if the product gas performance (concentration, pressure, flow rate) decreases, or the operation is stopped to maintain the product gas performance. It can be selected according to the user's request.

  Here, in the first and second embodiments, the PSA-type nitrogen generator having a pair of adsorption tanks 1 and 2 has been described. However, the present invention is not limited to this, and single and two or more adsorption tanks are used. You may have.

  In the first and second embodiments, the nitrogen generator that generates nitrogen gas is described as an example of the gas separation device. However, the present invention may be applied to an oxygen generator that generates oxygen gas, for example.

  The embodiments described so far are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention is not limitedly interpreted by these. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

DESCRIPTION OF SYMBOLS 1 ... Gas separation apparatus 2 ... Air supply unit 3 ... PSA unit 4 ... Compressor 5 ... Air tank (air storage tank)
6 ... Air dryer 7 ... Drain filter 18 ... Supply valve 19 ... Adsorption tank 22 ... Exhaust valve 23 ... Exhaust port 26 ... Lower pressure equalizing valve 33 ... Orifice 36・ ・ Upper pressure equalizing valve 38 ・ ・ ・ Taking valve 41 ・ ・ ・ Nitrogen tank (product gas storage tank)
42 ... Discharge port 44 ... Filter regulator 45 ... Discharge valve 46 ... Flow control valve 50 ... Open / close valve (for exhaust)
51 ... Flow rate adjustment valve (for exhaust)
52 ... Silencer 54 ... Open / close valve (for sensor)
55 ... Flow control valve (for sensor)
56 ... Oxygen sensor 57 ... Flow rate sensor 58 ... Pressure sensor 60 ... Control unit

Claims (10)

A plurality of compressors for compressing air;
An adsorption tank for adsorbing a part of the air compressed by the compressor;
A controller that controls the operation of the compressor and supplies a compressed air to the adsorption tank to adsorb one gas; and a control unit that performs an extraction process of taking out another gas from the adsorption tank as a product gas. Prepared,
Wherein the controller reduced at the beginning the adsorption step, is operated compressor of the total number, the number of operating the compressor when the amount of product gas is reduced,
The gas separation device, wherein the number of operating units to be reduced is changed according to the amount of use .   The gas separation device according to claim 1, wherein the controller extends the time of the adsorption process and the extraction process when the number of operating compressors is reduced.   The gas separation device according to claim 1, wherein the control unit reduces the number of operating compressors one by one.   2. The gas separation device according to claim 1, wherein the control unit operates all the compressors when the usage amount of product gas increases after reducing the number of operating compressors.   When one of the plurality of compressors breaks down, it is possible to select in advance whether to stop other compressors or continue to operate other compressors. The gas separation device according to claim 1. A compression step of compressing air with a plurality of compressors;
An adsorption step of adsorbing a part of the air compressed by the compressor from the air compressed by the compression step to an adsorption tank, and an extraction step of taking out another gas from the adsorption tank as a product gas,
Wherein the compression step, the is operated compressor of the total number at the adsorption step begins, and reduce the number of operating the compressor when the amount of product gas is reduced,
A gas separation method, wherein the number of operating units to be reduced is changed according to the amount of use .   The gas separation method according to claim 6, wherein the time of the adsorption process and the extraction process is extended when the number of operating compressors is reduced.   The gas separation method according to claim 6, wherein in the compression step, the number of operating compressors is reduced by one.   The gas separation method according to claim 6, wherein, in the compression step, after reducing the number of operating compressors, when the amount of product gas used increases, all the compressors are operated.   In the compression step, when one of the plurality of compressors fails, it is possible to select in advance whether to stop other compressors or continue to operate other compressors. The gas separation method according to claim 6, wherein the gas separation method is performed.

Images