JP4685662B2 - Gas separation method and apparatus used therefor - Google Patents

Description

  The present invention relates to a gas separation method by a pressure vacuum swing adsorption (hereinafter referred to as “PVSA”) method and an apparatus used therefor.

Conventionally, as a gas separation method for separating oxygen gas or the like from a mixed gas such as air, a gas separation method based on the PVSA method is often used. In general, an oxygen gas generator using this gas separation method has two adsorption towers, a single-stage roots blower for supplying raw air (hereinafter referred to as “raw air blower”), and a single-stage for decompression regeneration. It is composed of a roots type blower (hereinafter referred to as “vacuum blower”), and basically the following three steps are performed in two cycles (see FIG. 14). That is, the raw air (N ₂ + O ₂ ) is compressed by an original blower and supplied to one adsorption tower, and nitrogen (N ₂ ) is selectively adsorbed to the adsorbent of this one adsorption tower, which is difficult to adsorb. An adsorption separation step of taking out (O ₂ ) as a product gas, a vacuum regeneration step of evacuating one of the adsorption towers by a vacuum blower and desorbing nitrogen adsorbed on the adsorbent of the one adsorption tower, and a product gas And a return pressure step that raises one adsorption tower to near atmospheric pressure using the atmosphere, and in two cycles (the return pressure step and the adsorption separation step are incorporated in one cycle) The above three steps are repeated in this order. In the other adsorption tower, the above three steps are performed in two cycles in a predetermined order (this order corresponds to the order of the one adsorption tower, followed by the decompression regeneration step, the decompression step, and the adsorption separation step). ) Repeatedly.

  Further, a two-stage roots type blower is often used for decompression regeneration. In this case, two vacuum blowers with different capacities are prepared, and in the decompression regeneration process, first, after evacuating only with a vacuum blower having a large capacity, the vacuum blowers are turned on when the compression ratio becomes high. Since decompression is performed while being connected in series, decompression regeneration pressure can be made lower than when a single-stage blower is used (see, for example, Patent Document 1).

  Further, in the gas separation method based on the PVSA method, in the case of a single tower type (that is, one adsorption tower), only a single-stage roots type blower that serves both as a raw air supply and a decompression regeneration is used. Is also used. In this case, the manufacturing cost can be reduced and the product becomes cheaper than that using two adsorption towers.

As such, a single bed pressure change adsorption system and method as shown in FIG. 15 has been proposed. This system includes a single adsorption bed 31 and a supply blower / vacuum blower unit 32 and the like. In the pressurization / product recovery process, raw air is supplied to the single adsorption bed 31 through the blower unit 32, and vacuum is supplied. In the exhaust and purge processes, the gas in the single adsorption bed 31 is discharged to the atmosphere through the blower unit 32 (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 10-296034 JP-A-7-96128

  However, as described above, the two-stage roots type blower is used for decompression regeneration, but is not actually used for adsorption separation. In addition, when a single-stage roots blower is used for both raw air supply and decompression regeneration, the single-stage roots type blower increases when the compression ratio of the single-stage roots blower increases. The load on the blower increases and power consumption increases. On the other hand, when aiming to reduce power consumption, the pressure is lowered when the raw material air is supplied (that is, the pressure during pressurization in the adsorption tower is lowered), and the pressure is increased during decompression regeneration (ie, inside the adsorption tower). However, if the pressure at the time of pressurization is reduced, the adsorption pressure of the adsorbent in the adsorption tower is lowered. On the other hand, if the pressure at the time of depressurization is increased, the adsorbent is reduced. The regeneration pressure increases. As a result, the pressure difference between the adsorption pressure at the time of pressurization and the regeneration pressure at the time of depressurization becomes small, and the effective adsorption amount of the adsorbent (this effective adsorption amount is absorbed by the adsorbent at the end of the adsorption separation process) This means a difference between the amount of gas present and the amount of gas adsorbed to the adsorbent at the end of the decompression regeneration process), and a large amount of adsorbent needs to be filled. Further, in the single-stage roots type blower, the set pressure is set near the maximum of the device specification pressure, so that the power consumption required for operation increases.

  The present invention has been made in view of such circumstances, a gas separation method capable of reducing power consumption, increasing the effective adsorption amount of the adsorbent by increasing the efficiency of adsorption separation and decompression regeneration, and The purpose is to provide a device used for the above.

In order to achieve the above object, the present invention is a gas separation method based on a pressure vacuum swing adsorption method, using a multistage blower that serves both as a source gas supply blower and a decompression regeneration blower, and performs adsorption separation. in step and vacuum regeneration step, the compression ratio of the blower of each stage of said plurality stage blower when less than the predetermined compression ratio, the blower of each stage of said plurality stage blowers operated in parallel, the plurality stage blowers When the compression ratio of each stage of the blower is larger than the predetermined compression ratio, the first aspect is a gas separation method in which the blowers of each stage of the multistage blower are operated in series. A gas separation device, an adsorption tower filled with an adsorbent that selectively adsorbs a specific gas, a raw material gas supply path for supplying the raw material gas to the adsorption tower in the adsorption separation step, A flow path provided with a multistage blower that serves as both a raw air supply blower and a reduced pressure regeneration blower in the raw material gas supply path. the provided, also serves as a part of the exhaust path in the flow path, the flow path, and a parallel state to connect the blower of each stage of said plurality stage blowers in parallel, each stage of said plurality stage blowers In the adsorption separation process and the decompression regeneration process, in the state where the blower compression ratio of each stage of the multistage blower is smaller than a predetermined compression ratio, the flow is the road parallel state, in the state the compression ratio is larger than the predetermined compression ratio of the blower of each stage of said plurality stage blower, a gas separation apparatus which is configured to the flow path in series state the second aspect And

That is, the gas separation method of the present invention is a gas separation method based on a pressure vacuum swing adsorption method, and a multistage blower that serves both as a source gas supply blower and a decompression regeneration blower is used. Then, in the adsorptive separation step and the vacuum regeneration step, when the compression ratio of the blower of each stage of said plurality stage blower is smaller than a predetermined compression ratio is operated in parallel with the blower of each stage of said plurality stage blower, said plurality the compression ratio of the blower of each stage of the stage blower is greater than the predetermined compression ratio, so that series operated blower of each stage of said plurality stage blower. Thus, in the gas separation method of the present invention, in the adsorptive separation step, when the compression ratio of the blower of each stage of said plurality stage blower is smaller than a predetermined compression ratio, the blower of each stage of said plurality stage blowers By operating in parallel, the amount of raw material air supplied into the adsorption tower can be increased, and the pressure at the time of pressurization in the adsorption tower can be increased in a short time operation. Next, when the compression ratio of each stage of the multistage blower becomes larger than the predetermined compression ratio, the suction pressure is increased with small power by operating the blowers of each stage of the multistage blower in series. The decompression regeneration pressure can be lowered. On the other hand, also in the vacuum regeneration step, when the compression ratio of the blower of each stage of said plurality stage blower is smaller than a predetermined compression ratio, by parallel operation of the blower of each stage of said plurality stage blowers, from the adsorption tower The amount of exhaust gas in the adsorption tower can be increased, and the pressure during decompression in the adsorption tower can be lowered by a short time operation.

  Further, when the pressure at the time of pressurization increases, the adsorption pressure of the adsorbent in the adsorption tower also increases (160 kPa or more), and when the pressure at the time of depressurization decreases, the regeneration pressure of the adsorbent decreases (40 kPa). As a result, the pressure difference between the adsorption pressure at the time of pressurization and the regeneration pressure at the time of depressurization increases, and the effective adsorption amount of the adsorbent increases correspondingly, and the filling amount of the adsorbent can be reduced. Further, by adjusting the time between the parallel operation and the serial operation, it is possible to adjust the blower capacity (the supply amount of raw material air and the power consumption), and from this point, the power consumption can be reduced. The present invention is suitably used in the case of a single tower type, and has the following effects. That is, normally, in a gas separation apparatus having a two-column type or higher adsorption tower, an original blower and a vacuum blower are separately required, and the operation cycle is determined by the time of the decompression regeneration process by the vacuum blower. . Therefore, the capacity of the raw air blower, for example, the capacity is determined by the operation cycle previously determined by the capacity of the vacuum blower. On the other hand, in the single-column gas separation apparatus, the original empty blower and the vacuum blower are used together, and the adsorption separation process using the original empty blower and the decompression regeneration process using the vacuum blower are not affected by other influences. Therefore, the optimal adsorption pressure and reduced pressure regeneration pressure can be set by appropriately setting the switching time from parallel operation to series operation and the respective operation times in each step. On the other hand, the gas separation device of the present invention also exhibits the above excellent effects.

  In the present invention, the predetermined compression ratio is set to 1.30 to 1.60 during pressurization, preferably about 1.40, and 1.42 to 2 during decompression. .45, and preferably about 1.65. When the predetermined compression ratio exceeds 1.60 at the time of pressurization and exceeds 2.45 at the time of depressurization, there is a problem that the load on the blower increases and the power consumption increases. If the pressure is lower than 1.42 at the time of decompression, the amount of raw material air supplied to the blower or the amount of exhaust gas is reduced, which causes a problem that the amount of product generated is reduced. Further, in the present invention, “using a multi-stage blower” is not limited to the case of using a plurality of single-stage blowers, as in a two-stage integral blower (or a multi-stage integral blower). When using a single unit that acts as a two-stage blower (or a multi-stage blower), or combining a single-stage blower and a two-stage integral blower (or a multi-stage integral blower) The case where it is used is also included.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to this embodiment.

  FIG. 1 shows an embodiment of the gas separation apparatus of the present invention. In this embodiment, a single-column PVSA system oxygen gas generator is used as the gas separator. In the figure, reference numerals 1 and 2 denote two-stage roots type blowers, which are composed of a first blower 1 having a large capacity and a second blower 2 having a small capacity. Reference numeral 3 denotes one adsorption tower, which is filled with an adsorbent (not shown) that selectively adsorbs nitrogen gas (specific gas) in the raw material air. 4 is a pressure equalizing tower for storing the oxygen-enriched gas recovered from the adsorption tower 3, and acts to restore the pressure of the adsorption tower 3 by supplying the recovered oxygen-enriched gas to the adsorption tower 3 that has finished the decompression regeneration process. Reference numeral 5 denotes a product tower for storing product oxygen gas taken out from the adsorption tower 3.

  Reference numeral 6 denotes a raw material air introduction path with a first on-off valve 6a for introducing the raw material air from the outside, and reference numerals 7 and 8 denote branch paths branched from the raw material air introduction path 6. The first branch path 7 has a first blower 1, The first check valve 9 is arranged in this order from the upstream side of the flow of raw material air. A second check valve 10 and a second blower 2 are disposed in the second branch path 8 in this order from the upstream side. 11 is a portion between the blower check valves of the first branch passage 7 (a portion between the first blower 1 and the first check valve 9) and a portion between the blower check valves of the second branch passage 8 (the second blower 2). And a portion between the second check valve 10 and the second check valve 10). Reference numeral 12 denotes a combined flow path where both the branched paths 7 and 8 are joined, and is connected to the inlet path 14 of the adsorption tower 3 via the raw air connection path 13 with the third on-off valve 13a. 15 is a fourth on-off valve that connects the end portion of the inlet passage 14 (the upstream end portion of the flow of raw material air) and the blower upstream portion of the first branch passage 7 (upstream portion of the first blower 1). 15a is an exhaust connection path. Reference numeral 16 denotes a discharge path with a fifth on-off valve 16a extending from the end of the combined flow path 12 (end on the downstream side of the flow of raw material air).

  Reference numeral 17 denotes an outlet path of the adsorption tower 3, and 18 denotes an oxygen gas extraction path with a third check valve 19 and a sixth on-off valve 18 a extending from the outlet path 17. Reference numeral 20 denotes an oxygen gas flow path extending from the product tower 5, and is connected to a portion between the oxygen gas extraction passage 18 (a portion between the third check valve 19 and the sixth on-off valve 18 a). Reference numeral 21 denotes an oxygen gas introduction path with a seventh on-off valve 21 a extending from the pressure equalizing tower 4, and is connected to the outlet path 17.

  In the above configuration, when the adsorption separation step is performed, as shown in FIG. 2, the first, third, and sixth on-off valves 6a, 13a, and 18a are opened, and the second, fourth, fifth, The seventh on-off valves 11a, 15a, 16a and 21a are closed. As a result, both the blowers 1 and 2 are connected in parallel, both the blowers 1 and 2 perform the load operation (both the blowers 1 and 2 are operated for supplying the raw material gas), and the raw material air introduction path 6 Is fed to the adsorption tower 3 via both branch paths 7 and 8, the combined flow path 12, the feed air connection path 13, and the inlet path 14 (this parallel operation is performed in both the blowers 1 and 2. Performed when the compression ratio is 1.4 or less). When the raw air is supplied by the parallel operation of both blowers 1 and 2, the pressure in the adsorption tower 3 rises and the compression ratio of both blowers 1 and 2 increases (becomes 1.4 or more). As shown, the second on-off valve 11a is automatically opened. As a result, both the blowers 1 and 2 are connected in series. Both the blowers 1 and 2 perform the load operation, and the raw air introduced from the raw air introduction path 6 is supplied to the first branch path 7 and the connection path 11. , The second branch path 8, the combined path 12, the feed air connection path 13, and the inlet path 14 are supplied to the adsorption tower 3.

  On the other hand, when performing decompression exhaust, as shown in FIG. 4, the 4th-6th on-off valve 15a, 16a, 18a is opened, and the 1st-3rd, 7th on-off valve 6a, 11a, 13a, 21a is closed. As a result, both blowers 1 and 2 are connected in parallel, both blowers 1 and 2 perform load operation (both blowers 1 and 2 are operated for decompression regeneration), and the inside of the adsorption tower 3 is entered. Exhaust pressure is reduced through the passage 14, the exhaust connection passage 15, both branch passages 7 and 8, the combined passage 12, and the discharge passage 16 (in this parallel operation, the compression ratio of the blowers 1 and 2 is 1.65 or less. Sometimes done). Then, when the pressure in the adsorption tower 3 is reduced by the reduced pressure exhaustion by the parallel operation of both the blowers 1 and 2 and the compression ratio of both the blowers 1 and 2 is increased (above 1.65), it is shown in FIG. As described above, the second on-off valve 11a is automatically opened. As a result, both the blowers 1 and 2 are connected in series, both the blowers 1 and 2 perform load operation, and the inside of the adsorption tower 3 is connected to the inlet path 14, the exhaust connection path 15, the first branch path 7, Vacuum exhaust is performed through the connection path 11, the second branch path 8, the combined path 12, and the discharge path 16.

  2 to 5, among the first to seventh on-off valves 6a, 11a, 13a, 15a, 16a, 18a, and 21a, those that are painted black are closed and are not painted black. Indicates that the valve is open. Moreover, among the paths 6-8, 11-18, 20, and 21, the ones represented by thick lines indicate that gas is circulating, and the ones represented by thin lines indicate that no gas is circulating. ing. The same applies to FIGS. 6 to 13 described later.

As described above, in this embodiment, when both the blowers 1 and 2 are used and the compression ratio of both the blowers 1 and 2 is small in the adsorption separation process and the decompression regeneration process, the two blowers 1 and 2 are operated in parallel. When the compression ratio is large, series operation is performed. For this reason, the pressure at the time of pressurization can be increased and the adsorption pressure of the adsorbent can be increased, and the pressure at the time of depressurization can be decreased and the regeneration pressure of the adsorbent can be decreased. As a result, the pressure difference between the adsorption pressure and the regeneration pressure increases, and the effective adsorption amount (nitrogen) of the adsorbent can be increased. In addition, when the compression ratios of the blowers 1 and 2 are large, series operation is performed, thereby reducing power consumption.

  6 to 13 show an example of a gas separation method performed using a gas separation device (one-column type PVSA type oxygen gas generator) having the same structure as that of the above embodiment.

  In the gas separation method of this example, first, a parallel adsorption separation step (see FIG. 6) is performed. In this parallel adsorption separation step, the first, third, and sixth on-off valves 6a, 13a, and 18a are opened to provide the second, fourth, fifth, and seventh as in the adsorption separation step of the above embodiment. The on-off valves 11a, 15a, 16a, 21a are closed. As a result, both the blowers 1 and 2 are connected in parallel, both the blowers 1 and 2 perform the load operation (both the blowers 1 and 2 are operated for supplying the raw material gas), and the raw material air introduction path 6 Is fed to the adsorption tower 3 via both branch paths 7 and 8, the combined flow path 12, the feed air connection path 13, and the inlet path 14 (this parallel operation is performed in both the blowers 1 and 2. Performed when the compression ratio is 1.4 or less). Thus, by supplying raw material air to the adsorption tower 3 in a state where both the blowers 1 and 2 are operated in parallel, the supply amount of raw material air can be increased and the pressure in the adsorption tower 3 can be increased in a short time. . On the other hand, the product oxygen gas stored in the product tower 5 is taken out from the oxygen gas take-out path 18.

  When the raw material air is supplied by the parallel operation of the blowers 1 and 2, the gas pressure in the adsorption tower 3 rises and the compression ratio of the blowers 1 and 2 increases (1.4 or more). As shown in FIG. 7, the second on-off valve 11a is automatically opened to perform the serial adsorption separation process. In this step, both the blowers 1 and 2 are connected in series, and the raw air introduced from the raw air introduction path 6 is supplied to the first branch path 7, the connection path 11, the second branch path 8, the combined path 12, The raw material air is supplied to the adsorption tower 3 via the connection path 13 and the inlet path 14. Thus, by supplying raw material air to the adsorption tower 3 in a state where both the blowers 1 and 2 are operated in series, the adsorption pressure of the adsorbent in the adsorption tower 3 can be increased with small power. In the third check valve 19, the gas pressure in the product tower 5 is lower than the gas pressure in the adsorption tower 3 in the parallel adsorption separation process or the serial adsorption separation process (usually in the parallel adsorption separation process). The valve is sometimes opened, and the product oxygen gas in the adsorption tower 3 is taken out to the product tower 5 or the oxygen gas take-out path 18.

  On the other hand, when performing vacuum exhaust, a recovery process is first performed (see FIG. 8). In this collection step, the fourth to seventh on-off valves 15a, 16a, 18a, and 21a are opened, and the first to third on-off valves 6a, 11a, and 13a are closed. As a result, both blowers 1 and 2 are connected in parallel, both blowers 1 and 2 perform load operation (both blowers 1 and 2 are operated for decompression regeneration), and the inside of the adsorption tower 3 is entered. Exhaust pressure is reduced through the passage 14, the exhaust connection passage 15, both branch passages 7 and 8, the combined passage 12, and the discharge passage 16 (in this parallel operation, the compression ratio of the blowers 1 and 2 is 1.65 or less. Sometimes done). On the other hand, the product oxygen gas remaining in the adsorption tower 3 is recovered in the pressure equalizing tower 4 through the oxygen gas introduction path 21 to increase the recovery rate of the product oxygen gas, and the product oxygen gas stored in the product tower 5 is converted into oxygen. Take out from the gas outlet 18.

  Next, a parallel decompression regeneration process is performed (see FIG. 9). In this parallel regeneration step, the seventh on-off valve 21a is closed from the state shown in FIG. 8, and the recovery of the product oxygen gas is stopped. On the other hand, the vacuum exhaust in the adsorption tower 3 is continued. Thereby, at the start of the parallel decompression regeneration step, decompression exhaust is performed with both blowers 1 and 2 operating in parallel, the exhaust amount from the adsorption tower 3 is increased, and the pressure in the adsorption tower 3 is lowered in a short time. be able to.

  When the gas pressure in the adsorption tower 3 is lowered by the reduced pressure exhaustion due to the parallel operation of the blowers 1 and 2 and the compression ratio of the blowers 1 and 2 is increased (becomes 1.65 or more), FIG. As shown, the second on-off valve 11a is automatically opened to perform the series decompression regeneration process. In this step, both blowers 1 and 2 are connected in series, and the inside of the adsorption tower 3 is connected to the inlet path 14, the exhaust connection path 15, the first branch path 7, the connection path 11, the second branch path 8, and the merge. Vacuum exhaust is performed via the passage 12 and the discharge passage 16. In this way, the reduced pressure regeneration pressure of the adsorbent in the adsorption tower 3 can be lowered with a small power by exhausting the reduced pressure while both the blowers 1 and 2 are operated in series.

  Next, a pressure equalizing step is performed (see FIG. 11). In this pressure equalization process, the seventh on-off valve 21a is opened from the state shown in FIG. 10, and the oxygen rich gas (product oxygen gas) recovered in the pressure equalization tower 4 in the recovery process is introduced into the adsorption tower 3 as a pressure-reducing gas. And increase the recovery rate of product oxygen gas.

  Next, a rinsing step is performed (see FIG. 12). In this rinsing step, the first, fifth and sixth on-off valves 6a, 16a and 18a are opened, and the second to fourth and seventh on-off valves 11a, 13a, 15a and 21a are closed. As a result, both the blowers 1 and 2 are connected in parallel, both the blowers 1 and 2 perform no-load operation, the raw air is introduced from the raw air introduction path 6, the two branch paths 7 and 8 are merged It emits to the atmosphere via the path 12 and the discharge path 16. In this way, the nitrogen-rich gas remaining in the branch paths 7 and 8, the combined flow path 12, and the discharge path 16 is replaced with the raw material air.

  After that, a decompression step (see FIG. 13) is performed. In this return pressure step, the third on-off valve 13a is opened from the state shown in FIG. 12, and both the blowers 1 and 2 are operated for load (both the blowers 1 and 2 are connected in parallel, The raw material air introduced from the raw material air introduction path 6 is supplied to the adsorption tower 3 via both branch paths 7 and 8, the combined flow path 12, the raw material air connection path 13, and the inlet path 14. Then, the adsorption tower 3 is decompressed. Further, the atmosphere is introduced from the discharge path 16 into the combined flow path 12 and supplied to the adsorption tower 3 via the raw air connection path 13 and the inlet path 14, and the adsorption tower 3 is also decompressed by the atmosphere. Further, the third check valve 19 is closed in the recovery process to the pressure recovery process so far.

  The gas separation method of this example also has the same operations and effects as the above embodiment.

  Next, examples and comparative examples of the present invention will be described.

[Examples and Comparative Examples]
In the examples shown in FIGS. 6 to 13, the following apparatus is used. In the example, switching between parallel operation and series operation is performed in both the adsorption separation process and the decompression regeneration process. In Comparative Example 2, only parallel operation was performed in the adsorption separation process, and switching between parallel operation and series operation was performed in the decompression regeneration process.

In the above apparatus, the adsorption tower 3 having an adsorption tower diameter of 600 A (inner diameter: 609.6 mm), an adsorbent filling height: 1359 mm, and an adsorbent filling amount: 240 kg was used. Further, a pressure equalizing tank 4 having a capacity of 0.9 m ³ was used, and a product tank 5 having a capacity of 1.5 m ³ was used. In addition, as blowers 1 and 2, model: two-stage integrated roots type blower, air volume: 17.5 m ³ / min at 40 ° C. atmospheric pressure (during parallel operation of two-stage integrated roots type blower), motor capacity: 30 kW Were used to measure adsorption pressure (maximum), decompression regeneration pressure (minimum), and power consumption. The measurement results are shown in Table 1. In Table 1, the operation cycle is adjusted so that the current values of the blowers 1 and 2 do not exceed 100 A as the operation conditions. ΔP is a value of adsorption pressure (maximum) −reduced pressure regeneration pressure (minimum). In addition, “Nm ³ ” of the amount of product generated and the unit of electric power indicates “m ³ (Normal)”.

  As apparent from Table 1 above, the value of ΔP is higher in the example than in both comparative examples 1 and 2, and it can be seen that the adsorption pressure of the adsorbent is higher. Moreover, the value of the power consumption rate is lower in the example than in both comparative examples 1 and 2, indicating that the power consumption is reduced.

It is explanatory drawing which shows one Embodiment of the gas separation apparatus of this invention. It is explanatory drawing which shows the effect | action of the said gas separation apparatus. It is explanatory drawing which shows the effect | action of the said gas separation apparatus. It is explanatory drawing which shows the effect | action of the said gas separation apparatus. It is explanatory drawing which shows the effect | action of the said gas separation apparatus. It is explanatory drawing which shows an example of the gas separation method of this invention. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is explanatory drawing which shows the said gas separation method. It is process explanatory drawing at the time of using two adsorption towers. It is a block diagram which shows a prior art example.

Explanation of symbols

1, 2 blower

Claims (4)

A gas separation method using a pressure vacuum swing adsorption method, wherein a multistage blower that serves both as a source gas supply blower and a decompression regeneration blower is used, and in the adsorption separation process and the decompression regeneration process, the multiple stage blower is used. when the compression ratio of the blower of each stage is smaller than the predetermined compression ratio, and parallel operation blower of each stage of said plurality stage blower, the compression the compression ratio of the blower of each stage of said plurality stage blowers is the predetermined A gas separation method characterized in that when the ratio exceeds the ratio, the blowers of each stage of the multistage blower are operated in series.   The gas separation method according to claim 1, wherein the pressure vacuum swing adsorption method is a single tower type. A gas separation device using a pressure vacuum swing adsorption method, an adsorption tower filled with an adsorbent that selectively adsorbs a specific gas, a raw material gas supply path for supplying the raw material gas to the adsorption tower in the adsorption separation step, and a reduced pressure An exhaust passage for depressurizing and exhausting the adsorption tower in the regeneration step, and a flow in which a multistage blower that serves both as a feed air supply blower and a decompression regeneration blower is disposed in the feed gas supply passage. the road provided, also serves as a part of the exhaust path in the flow path, the flow path, and a parallel state to connect the blower of each stage of said plurality stage blowers in parallel, each stage of said plurality stage blowers In the state where the compression ratio of the blowers in each stage of the multistage blower is smaller than a predetermined compression ratio in the adsorption separation process and the decompression regeneration process, the above - described blower is connected in series. Side by side The state, in a state compression ratio is larger than the predetermined compression ratio of the blower of each stage of said plurality stage blower, gas separation apparatus characterized by being configured to the flow path in series state.   The gas separator according to claim 3, wherein the pressure vacuum swing adsorption system is a single tower type.

Images