Gas production system, and gas production apparatus

Abstract

To improve gas production efficiency.SOLUTION: When a flow rate of hydrogen gas supplied from a single gas supply source A1 is less than a predetermined flow rate, a gas production system 1 sequentially switches a specific gas production apparatus 10 operated in a plurality of gas production apparatuses 10. Therefore, a state in which a regeneration process is not executed in a first adsorption cylinder 11 and a second adsorption cylinder 12 can be prevented from being continuous for a long period of time. Accordingly, an equilibrium state of moisture amounts of a first adsorbent 13 and a second adsorbent 14 is suppressed in the first adsorbent cylinder 11 and the second adsorption cylinder 12. When the flow rate of the hydrogen gas supplied from the single gas supply source A1 becomes comparatively large, for example, the moisture amounts of the first adsorbent 13 and the second adsorbent 14 become in the equilibrium state, the problem that it becomes difficult to sufficiently execute an adsorption process is avoided. As a result, deterioration in starting of the gas production system 1 is avoided.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a gas production system and a gas production apparatus. [Background technology]

[0002] In order to use a single gas such as hydrogen gas or oxygen gas as a dry gas, it is necessary to adsorb moisture contained in the single gas to convert it into a dry gas. Thus, a gas production apparatus equipped with an adsorption tube containing an adsorbent therein is known. In such a gas production apparatus, an adsorption process and a regeneration process are alternately and repeatedly performed in the adsorption tube. In the adsorption process, the adsorbent adsorbs moisture contained in the single gas supplied into the adsorption tube through a supply line from a single gas supply source. In the regeneration process, the adsorbent is regenerated by removing moisture contained in the adsorbent after the adsorption process. The gas production apparatus is equipped with a plurality of adsorption tubes so that the adsorption process can be performed in another adsorption tube until the adsorbent is regenerated in the regeneration process after the adsorption process and the adsorption process is performed again in the adsorption tube containing the adsorbent therein.

[0003] In such a gas production apparatus, as in Patent Document 1, for example, in the regeneration process, it is considered that a part of the single gas flowing through the supply line is heated by a heating unit and then supplied to the adsorption tube, which is the target for the regeneration process. In this way, the moisture contained in the adsorbent in the adsorption tube, which is the target for the regeneration process, is desorbed by the high-temperature single gas heated by the heating unit. This regenerates the adsorbent in the adsorption tube, which is the target for the regeneration process. Then, the single gas discharged from the adsorption tube during the regeneration process is cooled by a cooling unit to recover the moisture contained in the single gas, and then the gas is returned to the supply line. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 1-310717 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in order to deal with fluctuations in the flow rate of the single gas supplied from the single gas supply source, for example, a gas production system equipped with a plurality of gas production devices has been considered. When the flow rate of the single gas supplied from the single gas supply source is relatively high, as many gas production devices as possible are operated, making it possible to produce dry gas corresponding to the flow rate of the single gas supplied from the single gas supply source. On the other hand, when the flow rate of the single gas supplied from the single gas supply source is relatively low, a specific gas production device among the plurality of gas production devices is operated and the other gas production devices are stopped. In this way, it is possible to avoid the gas production device from operating unnecessarily even though the flow rate of the single gas supplied from the single gas supply source is low, and therefore it is possible to reduce the running cost in the gas production system.

[0006] In addition, in order to deal with fluctuations in the flow rate of the single gas supplied from the single gas supply source, for example, a gas production apparatus having three or more adsorption tubes has been considered. When the flow rate of the single gas supplied from the single gas supply source is relatively high, the adsorption process is performed in as many adsorption tubes as possible, making it possible to produce dry gas corresponding to the flow rate of the single gas supplied from the single gas supply source. On the other hand, when the flow rate of the single gas supplied from the single gas supply source is relatively low, the adsorption process is performed in a specific adsorption tube among the three or more adsorption tubes, and neither the adsorption process nor the regeneration process is performed in the other adsorption tubes. In this way, it is possible to avoid the adsorption tubes from performing the adsorption process unnecessarily even though the flow rate of the single gas supplied from the single gas supply source is low, thereby reducing the running costs of the gas production apparatus.

[0007] However, if the regeneration process is not performed in the adsorption column for a long time, the moisture content of the adsorbent in the adsorption column may reach an equilibrium state. If the moisture content of the adsorbent reaches an equilibrium state when the flow rate of the single gas supplied from the single gas supply source becomes relatively high, it becomes difficult for the adsorption column that contains the adsorbent to perform the adsorption process sufficiently. Therefore, for example, in order to regenerate the adsorbent, it is necessary to supply a gas other than the single gas into the adsorption column to regenerate the adsorbent sufficiently. In this way, the start-up of the gas production system or gas production device becomes poor, and the gas production efficiency deteriorates. [Means for solving the problem]

[0008] Various aspects for solving the above problems will be described below. [Aspect 1] Equipped with multiple gas production equipment, Each of the gas production devices is An adsorption cylinder that contains an adsorbent therein, an adsorption step of adsorbing moisture contained in a single gas supplied from a single gas supply source into the adsorption cylinder through a supply line with the adsorbent, and a regeneration step of desorbing moisture contained in the adsorbent after the adsorption step to regenerate the adsorbent, the adsorption step being repeated alternately in the adsorption cylinder, thereby producing a dry gas by adsorbing moisture with the adsorbent in the adsorption step; a plurality of adsorption cylinders are provided so that the adsorption step can be carried out in another adsorption cylinder until the adsorption step is carried out again in the adsorption cylinder containing the adsorbent after the adsorption step by regenerating the adsorbent in the regeneration step; In the regeneration step, a portion of the single gas flowing through the supply line is heated by a heating unit and then supplied into an adsorption column which is a target for carrying out the regeneration step, and the single gas discharged from the adsorption column during the regeneration step is cooled by a cooling unit to recover moisture contained in the single gas, and then the single gas is returned to the supply line, A gas production system comprising: a gas production apparatus that sequentially switches between a specific gas production apparatus to be operated among the plurality of gas production apparatuses when a flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate.

[0009] [Aspect 2] The gas production system according to [Aspect 1], characterized in that when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the specific gas production device to be operated among the plurality of gas production devices is sequentially switched every time a specified time has elapsed.

[0010] [Aspect 3] The gas production system according to [Aspect 1] or [Aspect 2], characterized in that when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the gas production apparatus among the plurality of gas production apparatuses that has had the longest downtime is operated preferentially.

[0011] [Aspect 4] An adsorption cylinder that contains an adsorbent therein, an adsorption step of adsorbing moisture contained in a single gas supplied from a single gas supply source into the adsorption cylinder through a supply line with the adsorbent, and a regeneration step of desorbing moisture contained in the adsorbent after the adsorption step to regenerate the adsorbent, the adsorption step being repeated alternately in the adsorption cylinder, thereby producing a dry gas by adsorbing moisture with the adsorbent in the adsorption step; three or more adsorption cylinders are provided so that the adsorption step can be carried out in another adsorption cylinder until the adsorption step is carried out again in the adsorption cylinder containing the adsorbent after the adsorption step by regenerating the adsorbent in the regeneration step; In the gas production apparatus, in the regeneration step, a portion of the single gas flowing through the supply line is heated by a heating unit and then supplied into an adsorption column which is a target for carrying out the regeneration step, and the single gas discharged from the adsorption column during the regeneration step is cooled by a cooling unit to recover moisture contained in the single gas, and then the single gas is returned to the supply line, A gas production apparatus characterized in that, when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the adsorption process is carried out in the three or more adsorption columns, and then a specific adsorption column is sequentially switched to carry out the regeneration process.

[0012] [Aspect 5] The gas production apparatus according to [Aspect 4], characterized in that when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the adsorption process is performed in the three or more adsorption columns, and then a specific adsorption column in which the regeneration process is performed is sequentially switched every time a specified time has elapsed.

[0013] [Aspect 6] The gas production apparatus according to [Aspect 4] or [Aspect 5], characterized in that, when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the adsorption tube that has not been subjected to either the adsorption process or the regeneration process for the longest period of time among the three or more adsorption tubes is caused to perform the adsorption process and the regeneration process preferentially. Effect of the Invention

[0014] According to the present invention, the gas production efficiency can be improved. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing a gas production system according to the first embodiment. [Diagram 2] FIG. 2 is a diagram for explaining an example of control by the control device. [Diagram 3] FIG. 3 is a diagram for explaining an example of control by the control device. [Figure 4] FIG. 4 is a diagram for explaining an example of control by the control device. [Diagram 5] FIG. 5 is a diagram for explaining the operation of the first embodiment. [Figure 6] FIG. 6 is a schematic diagram showing a gas production apparatus according to the second embodiment. [Figure 7] FIG. 7 is a diagram for explaining an example of control by the control device. [Figure 8] FIG. 8 is a diagram for explaining an example of control by the control device. [Figure 9] FIG. 9 is a diagram for explaining an example of control by the control device. [Figure 10] FIG. 10 is a diagram for explaining the operation of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] [First embodiment] A first embodiment of a gas production system will be described below with reference to FIGS.

[0017] <Outline of gas production system> As shown in Fig. 1, the gas production system 1 includes a plurality of gas production apparatuses 10. The gas production system 1 of this embodiment includes three gas production apparatuses 10. In the following description, each gas production apparatus 10 may be referred to as a "first gas production apparatus 10A," a "second gas production apparatus 10B," and a "third gas production apparatus 10C."

[0018] The gas production system 1 includes a supply pipe 2 and an exhaust pipe 3. The supply pipe 2 is connected to a single gas supply source A1. The single gas supplied from the single gas supply source A1 is hydrogen gas. The hydrogen gas is wet hydrogen gas containing moisture produced by electrolysis. The exhaust pipe 3 is connected to a supply target (not shown) of the dry gas produced by the gas production system 1.

[0019] <Gas manufacturing equipment> Next, the configuration of the gas production apparatus 10 will be described. The first gas production apparatus 10A, the second gas production apparatus 10B, and the third gas production apparatus 10C have the same configuration. The first gas production apparatus 10A, the second gas production apparatus 10B, and the third gas production apparatus 10C are connected in parallel to the supply pipe 2 and the exhaust pipe 3.

[0020] The gas production apparatus 10 includes a first adsorption column 11 and a second adsorption column 12. The first adsorption column 11 is an adsorption column that houses a first adsorbent 13 as an adsorbent therein. The second adsorption column 12 is an adsorption column that houses a second adsorbent 14 as an adsorbent therein. Thus, the gas production apparatus 10 includes a plurality of adsorption columns. The first adsorbent 13 and the second adsorbent 14 are configured to be capable of adsorbing moisture. Examples of the first adsorbent 13 and the second adsorbent 14 include activated alumina, silica gel, and synthetic zeolite. The gas production apparatus 10 produces dry gas by adsorbing moisture contained in hydrogen gas with the first adsorbent 13 or the second adsorbent 14.

[0021] The gas production device 10 includes a first pipe 15, a second pipe 16, and a third pipe 17. A first end of the first pipe 15 is connected to the supply pipe 2. Therefore, hydrogen gas supplied from the single gas supply source A1 flows through the first pipe 15 via the supply pipe 2. A first end of the first pipe 15 of each gas production device 10 is connected in parallel to the supply pipe 2. The hydrogen gas flowing from the single gas supply source A1 to the supply pipe 2 branches and flows into each first pipe 15.

[0022] A first end of the second pipe 16 and a first end of the third pipe 17 are each connected to the second end of the first pipe 15. Therefore, the second pipe 16 and the third pipe 17 branch off from the second end of the first pipe 15. The second end of the second pipe 16 is connected to the first port 11a of the first adsorption column 11. The second end of the third pipe 17 is connected to the first port 12a of the second adsorption column 12.

[0023] The gas production device 10 has a fourth pipe 18, a fifth pipe 19, and a sixth pipe 20. A first end of the fourth pipe 18 is connected to the second port 11b of the first adsorption column 11. A first end of the fifth pipe 19 is connected to the second port 12b of the second adsorption column 12. A first end of the sixth pipe 20 is connected to the second end of the fourth pipe 18 and the second end of the fifth pipe 19, respectively. Therefore, the fourth pipe 18 and the fifth pipe 19 merge into the sixth pipe 20. A second end of the sixth pipe 20 is connected to the discharge pipe 3. A dry gas produced by adsorbing moisture contained in hydrogen gas by the first adsorbent 13 or the second adsorbent 14 flows in the sixth pipe 20. A second end of the sixth pipe 20 of each gas production device 10 is connected to the discharge pipe 3 in parallel. The dry gas flowing in each sixth pipe 20 merges into the discharge pipe 3.

[0024] The gas manufacturing apparatus 10 includes a seventh pipe 21. A first end of the seventh pipe 21 is connected to the first pipe 15. Thus, the seventh pipe 21 branches off from the first pipe 15. A second end of the seventh pipe 21 is connected to a junction of the fourth pipe 18 and the fifth pipe 19 with the sixth pipe 20. The seventh pipe 21 is provided with a heating unit 22. The heating unit 22 is an electric heater that heats a portion of the seventh pipe 21 from the surroundings.

[0025] The gas production device 10 includes an eighth pipe 23. A first end of the eighth pipe 23 is connected to a branch point of the second pipe 16 and the third pipe 17 from the first pipe 15. A second end of the eighth pipe 23 is connected to a portion of the first pipe 15 closer to the second pipe 16 and the third pipe 17 than the connection point of the first pipe 15 with the seventh pipe 21.

[0026] The eighth pipe 23 is provided with a cooling unit 24. The cooling unit 24 is a water-cooled cooler. The cooling unit 24 is configured to be able to cool the hydrogen gas flowing through each of the eighth pipes 23. The eighth pipe 23 is provided with a drain recovery unit 25. The drain recovery unit 25 is provided in a portion of the eighth pipe 23 closer to the first pipe 15 than the cooling unit 24 is. The drain recovery unit 25 is configured to be able to recover moisture contained in the hydrogen gas flowing through the eighth pipe 23.

[0027] The gas production device 10 includes a first switching valve 31. The first switching valve 31 is provided at a connection point where the first pipe 15, the second pipe 16, the third pipe 17, and the eighth pipe 23 all join together. The first switching valve 31 is a four-way valve. The first switching valve 31 has a first port 31a, a second port 31b, a third port 31c, and a fourth port 31d. The first port 31a of the first switching valve 31 is connected to a second end of the first pipe 15. The second port 31b of the first switching valve 31 is connected to a first end of the second pipe 16. The third port 31c of the first switching valve 31 is connected to a first end of the third pipe 17. The fourth port 31d of the first switching valve 31 is connected to a first end of the eighth pipe 23.

[0028] The first switching valve 31 is configured to be switchable to a first switching state in which the first port 31a communicates with the second port 31b and the third port 31c communicates with the fourth port 31d. The first switching valve 31 is also configured to be switchable to a second switching state in which the first port 31a communicates with the third port 31c and the second port 31b communicates with the fourth port 31d.

[0029] The gas production device 10 includes a second switching valve 32. The second switching valve 32 is provided at a connection point where the fourth pipe 18, the fifth pipe 19, the sixth pipe 20, and the seventh pipe 21 all join together. The second switching valve 32 is a four-way valve. The second switching valve 32 has a first port 32a, a second port 32b, a third port 32c, and a fourth port 32d. The first port 32a of the second switching valve 32 is connected to a second end of the fourth pipe 18. The second port 32b of the second switching valve 32 is connected to a second end of the fifth pipe 19. The third port 32c of the second switching valve 32 is connected to a first end of the sixth pipe 20. The fourth port 32d of the second switching valve 32 is connected to a second end of the seventh pipe 21.

[0030] The second switching valve 32 is configured to be switchable to a first switching state in which the first port 32a communicates with the third port 32c and the second port 32b communicates with the fourth port 32d. The second switching valve 32 is also configured to be switchable to a second switching state in which the first port 32a communicates with the fourth port 32d and the second port 32b communicates with the third port 32c.

[0031] The gas production device 10 includes a first on-off valve 41. The first on-off valve 41 is a two-way valve. The first on-off valve 41 is provided in a portion of the first pipe 15 closer to the supply pipe 2 than the connection point with the seventh pipe 21. When the first on-off valve 41 is in an open state, it allows the flow of hydrogen gas through the first on-off valve 41 in the first pipe 15. On the other hand, when the first on-off valve 41 is in a closed state, it blocks the flow of hydrogen gas through the first on-off valve 41 in the first pipe 15.

[0032] The gas production apparatus 10 includes a second on / off valve 42. The second on / off valve 42 is a two-way valve. The second on / off valve 42 is provided in the sixth piping 20. When the second on / off valve 42 is in an open state, it allows the flow of hydrogen gas in the sixth piping 20. On the other hand, when the second on / off valve 42 is in a closed state, it blocks the flow of hydrogen gas in the sixth piping 20.

[0033] <Electrical configuration of the gas production system> The gas manufacturing system 1 includes a control device 35. The control device 35 includes a central processing unit (CPU). The control device 35 also includes a memory including a read-only memory (ROM) in which various programs and maps are stored in advance, and a random access memory (RAM) for temporarily storing the results of CPU calculations, etc. The control device 35 also includes a timer counter, an input interface, an output interface, etc.

[0034] The control device 35 is electrically connected to each of the first switching valves 31, each of the second switching valves 32, each of the first on-off valves 41, and each of the second on-off valves 42. The control device 35 collectively controls the operation of each of the first switching valves 31, the second switching valves 32, the first on-off valves 41, and the second on-off valves 42 of the three gas production devices 10. The control device 35 is also electrically connected to the heating units 22 and the cooling units 24 of the three gas production devices 10. The control device 35 collectively controls the operation of each of the heating units 22 and the cooling units 24 of the three gas production devices 10.

[0035] The control device 35 is electrically connected to an external control device 36 that controls the operation of the single gas supply source A1. The control device 35 receives a signal related to the flow rate of hydrogen gas supplied from the single gas supply source A1 from the external control device 36. The control device 35 also receives a signal from the external control device 36 that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx.

[0036] <Control of the control device> 2, a first program for executing an adsorption process in the first adsorption column 11 and a regeneration process in the second adsorption column 12 is stored in advance in the control device 35. In the first program, the first switching valve 31 is set to a first switching state, and the second switching valve 32 is set to the first switching state. In the first program, the first on-off valve 41 and the second on-off valve 42 are set to an open state.

[0037] When the first program is being executed, the first pipe 15 and the second pipe 16 form a supply line 43 that supplies hydrogen gas from the single gas supply source A1 into the first adsorption column 11. In the adsorption step of the first program, moisture contained in the hydrogen gas supplied from the single gas supply source A1 through the supply line 43 into the first adsorption column 11 is adsorbed by the first adsorbent 13. In this way, the gas production apparatus 10 produces dry gas by adsorbing moisture by the first adsorbent 13 in the adsorption step.

[0038] When the first program is being executed, the seventh pipe 21 and the fifth pipe 19 form a regeneration supply line 44 that branches off from the supply line 43 and supplies a portion of the hydrogen gas flowing through the supply line 43 into the second adsorption column 12, which is the target for performing the regeneration process.

[0039] In the regeneration step of the first program, a portion of the hydrogen gas flowing through the supply line 43 is heated by the heating unit 22 and then supplied into the second adsorption column 12, which is the target for the regeneration step. In the first program, the second adsorbent 14 in the second adsorption column 12, which is the target for the regeneration step, is regenerated. Therefore, in the regeneration step of the first program, the moisture contained in the second adsorbent 14 is removed after the adsorption step to regenerate the second adsorbent 14.

[0040] When the first program is being executed, the third pipe 17 and the eighth pipe 23 form a regeneration reflux line 45 that refluxes the hydrogen gas discharged from the second adsorption column 12 during the regeneration process to the supply line 43. In the first program, the hydrogen gas discharged from the second adsorption column 12 during the regeneration process is cooled by the cooling unit 24, and the moisture contained in the hydrogen gas is recovered by the drain recovery unit 25, and then the hydrogen gas is refluxed to the supply line 43.

[0041] 3, a second program for executing a regeneration process in the first adsorption column 11 and an adsorption process in the second adsorption column 12 is prestored in the control device 35. In the second program, the first switching valve 31 is set to the second switching state, and the second switching valve 32 is set to the second switching state. In the second program, the first on-off valve 41 and the second on-off valve 42 are set to the open state.

[0042] When the second program is being executed, the first pipe 15 and the third pipe 17 form a supply line 43 that supplies hydrogen gas from the single gas supply source A1 into the second adsorption column 12. In the adsorption step of the second program, moisture contained in the hydrogen gas supplied from the single gas supply source A1 through the supply line 43 into the second adsorption column 12 is adsorbed by the second adsorbent 14. In this way, the gas production apparatus 10 produces dry gas by adsorbing moisture by the second adsorbent 14 in the adsorption step.

[0043] When the second program is being executed, the seventh pipe 21 and the fourth pipe 18 form a regeneration supply line 44 that branches off from the supply line 43 and supplies a portion of the hydrogen gas flowing through the supply line 43 into the first adsorption column 11, which is the target for performing the regeneration process.

[0044] In the regeneration step of the second program, a portion of the hydrogen gas flowing through the supply line 43 is heated by the heating unit 22 and then supplied into the first adsorption column 11, which is the target for the regeneration step. Then, in the second program, the first adsorbent 13 in the first adsorption column 11, which is the target for the regeneration step, is regenerated. Therefore, in the regeneration step of the second program, the moisture contained in the first adsorbent 13 is removed after the adsorption step to regenerate the first adsorbent 13.

[0045] When the second program is being executed, the second piping 16 and the eighth piping 23 form a regeneration reflux line 45 that refluxes the hydrogen gas discharged from the first adsorption column 11 during the regeneration process to the supply line 43. In the second program, the hydrogen gas discharged from the first adsorption column 11 during the regeneration process is cooled by the cooling unit 24, and the moisture contained in the hydrogen gas is recovered by the drain recovery unit 25, and then the hydrogen gas is refluxed to the supply line 43.

[0046] The control device 35 stores in advance a program for switching to the second program after a certain time has elapsed since switching to the first program. The "certain time" is the time it is estimated that the moisture contained in the second adsorbent 14 in the second adsorption column 12 has been sufficiently desorbed. This "certain time" is determined in advance by an experiment or the like.

[0047] The control device 35 stores in advance a program for switching to the first program after a certain time has elapsed since switching to the second program. The "certain time" is the time it is estimated that the moisture contained in the first adsorbent 13 in the first adsorption column 11 has been sufficiently desorbed. This "certain time" is determined in advance by an experiment or the like.

[0048] In this way, the gas production apparatus 10 produces dry gas by alternately and repeatedly performing the adsorption process and the regeneration process in the first adsorption column 11 and the second adsorption column 12, thereby adsorbing moisture with the first adsorbent 13 and the second adsorbent 14 in the adsorption process. Therefore, the gas production apparatus 10 is provided with a plurality of adsorption columns so that the adsorption process can be performed in another adsorption column until the adsorption process is performed again in the adsorption column that contains the adsorbent after the adsorption process by regenerating the adsorbent in the regeneration process.

[0049] As shown in FIG. 4, the control device 35 stores a program for controlling the operation of the first on-off valve 41 and the second on-off valve 42 of each gas production device 10 based on the flow rate of hydrogen gas supplied from the single gas supply source A1. FIG. 4 shows an example in which the first on-off valve 41 and the second on-off valve 42 of the first gas production device 10A are open, and the first on-off valve 41 and the second on-off valve 42 of the second gas production device 10B and the third gas production device 10C are closed. In this case, the first gas production device 10A is a specific gas production device 10 that is operating among the multiple gas production devices 10 because the first on-off valve 41 and the second on-off valve 42 are open. On the other hand, the second gas production device 10B and the third gas production device 10C are stopped because the first on-off valve 41 and the second on-off valve 42 are closed.

[0050] 5, for example, assume that the flow rate of hydrogen gas supplied from the single gas supply source A1 is equal to or greater than a predetermined flow rate Qx. In this case, the control device 35 opens the first on / off valves 41 and the second on / off valves 42 of all of the three gas production devices 10, and operates all of the three gas production devices 10.

[0051] For example, consider a case where the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx and is greater than a first predetermined flow rate Qx1, which is a flow rate less than the predetermined flow rate Qx. In this case, the control device 35 operates two of the three gas production devices 10 by opening the first on / off valve 41 and the second on / off valve 42 of the two gas production devices 10. Then, the control device 35 stops the operation of the remaining gas production device 10 by closing the first on / off valve 41 and the second on / off valve 42 of the remaining gas production device 10.

[0052] For example, consider a case where the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx and is equal to or less than the predetermined flow rate Qx1. In this case, the control device 35 operates one of the three gas production apparatuses 10 by opening the first on / off valve 41 and the second on / off valve 42 of the one gas production apparatus 10. Then, the control device 35 stops the operation of the remaining two gas production apparatuses 10 by closing the first on / off valve 41 and the second on / off valve 42 of the remaining two gas production apparatuses 10.

[0053] The control device 35 stores a program for sequentially switching a specific gas production device 10 to be operated among the three gas production devices 10 when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx. In detail, the control device 35 stores a program for sequentially switching a specific gas production device 10 to be operated among the three gas production devices 10 every time a specified time elapses when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx. Therefore, the gas production system 1 sequentially switches a specific gas production device 10 to be operated among the three gas production devices 10 every time a specified time elapses when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx. The "specified time" refers to a time that has elapsed after each gas production device 10 starts operating.

[0054] In this manner, when the flow rate of the hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the gas production system 1 sequentially switches between specific gas production apparatuses 10 to be operated among the multiple gas production apparatuses 10.

[0055] The control device 35 stores a program for preferentially operating the gas production device 10 that has been stopped for the longest time among the three gas production devices 10 when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx. Therefore, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the gas production system 1 preferentially operates the gas production device 10 that has been stopped for the longest time among the three gas production devices 10. The control device 35 measures the stoppage time of each gas production device 10 using a timer.

[0056] [Operation of the first embodiment] Next, the operation of the first embodiment will be described. As shown in Fig. 2, the control device 35 executes a first program to supply hydrogen gas supplied from the single gas supply source A1 through the supply pipe 2 into the first adsorption column 11 through the first pipe 15, the second pipe 16, and the first port 11a. Then, an adsorption process is performed in which moisture contained in the hydrogen gas supplied into the first adsorption column 11 is adsorbed by the first adsorbent 13. In this manner, the gas production device 10 produces dry gas by adsorbing moisture by the first adsorbent 13 in the adsorption process. The dry gas produced by carrying out the adsorption process in the first adsorption column 11 is supplied to a supply target of the dry gas through the second port 11b, the fourth pipe 18, the sixth pipe 20, and the exhaust pipe 3.

[0057] A portion of the hydrogen gas flowing through the first pipe 15 flows into the seventh pipe 21. The hydrogen gas flowing through the seventh pipe 21 is heated by the heating unit 22. The hydrogen gas heated by the heating unit 22 is then supplied into the second adsorption column 12 via the fifth pipe 19 and the second port 12b. A regeneration process is then performed in which the moisture contained in the second adsorbent 14 in the second adsorption column 12 is removed by the high-temperature hydrogen gas heated by the heating unit 22 to regenerate the second adsorbent 14. In this way, in the regeneration process, a portion of the hydrogen gas flowing through the supply line 43 is heated by the heating unit 22 and then supplied into the second adsorption column 12.

[0058] The hydrogen gas in the second adsorption column 12 flows through the eighth pipe 23 via the third pipe 17. The hydrogen gas flowing through the eighth pipe 23 is cooled by the cooling unit 24. Then, the moisture contained in the hydrogen gas cooled by the cooling unit 24 is recovered by the drain recovery unit 25. The hydrogen gas from which the moisture has been recovered by the drain recovery unit 25 is returned to the first pipe 15 via the eighth pipe 23. In this way, the hydrogen gas discharged from the second adsorption column 12 during the regeneration process is cooled by the cooling unit 24, and then returned to the supply line 43.

[0059] As shown in FIG. 3, the control device 35 executes the second program after a certain time has elapsed since the execution of the first program, and supplies hydrogen gas supplied from the single gas supply source A1 through the supply pipe 2 into the second adsorption column 12 through the first pipe 15, the third pipe 17, and the first port 12a. Then, an adsorption process is performed in which moisture contained in the hydrogen gas supplied into the second adsorption column 12 is adsorbed by the second adsorbent 14. In this way, the gas production device 10 produces dry gas by adsorbing moisture by the second adsorbent 14 in the adsorption process. The dry gas produced by performing the adsorption process in the second adsorption column 12 is supplied to a supply target of the dry gas through the second port 12b, the fifth pipe 19, the sixth pipe 20, and the exhaust pipe 3.

[0060] A portion of the hydrogen gas flowing through the first pipe 15 flows into the seventh pipe 21. The hydrogen gas flowing through the seventh pipe 21 is heated by the heating unit 22. The hydrogen gas heated by the heating unit 22 is then supplied into the first adsorption column 11 via the fourth pipe 18 and the second port 11b. A regeneration process is then performed in which the moisture contained in the first adsorbent 13 in the first adsorption column 11 is removed by the high-temperature hydrogen gas heated by the heating unit 22 to regenerate the first adsorbent 13. In this way, in the regeneration process, a portion of the hydrogen gas flowing through the supply line 43 is heated by the heating unit 22 and then supplied into the first adsorption column 11.

[0061] The hydrogen gas in the first adsorption column 11 flows through the eighth pipe 23 via the second pipe 16. The hydrogen gas flowing through the eighth pipe 23 is cooled by the cooling unit 24. Then, moisture contained in the hydrogen gas cooled by the cooling unit 24 is recovered by the drain recovery unit 25. The hydrogen gas from which moisture has been recovered by the drain recovery unit 25 is returned to the first pipe 15 via the eighth pipe 23. In this way, the hydrogen gas discharged from the first adsorption column 11 during the regeneration process is cooled by the cooling unit 24, and then returned to the supply line 43.

[0062] The control device 35 executes the first program after a certain time has elapsed since executing the second program. Therefore, after the adsorption process, the adsorbent is regenerated in the regeneration process, and the adsorption process is executed again in the adsorption tube that contains the adsorbent. In this way, the adsorption process and the regeneration process are alternately and repeatedly executed in the adsorption tube, whereby the adsorbent adsorbs moisture in the adsorption process, thereby producing dry gas.

[0063] As shown in Figures 4 and 5, when the control device 35 receives a signal from the external control device 36 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, it sequentially switches between the specific gas production devices 10 to be operated among the three gas production devices 10.

[0064] 5, for example, the control device 35 receives a signal from the external control device 36 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx and is equal to or less than a predetermined flow rate Qx1. Then, the control device 35 operates the first gas production apparatus 10A and stops the second gas production apparatus 10B and the third gas production apparatus 10C. Then, after a predetermined time has elapsed since the first gas production apparatus 10A started operating, the control device 35 stops the first gas production apparatus 10A and operates the second gas production apparatus 10B.

[0065] Furthermore, after a predetermined time has elapsed since the second gas production apparatus 10B started operating, the control device 35 stops the second gas production apparatus 10B and operates the third gas production apparatus 10C. At this time, the third gas production apparatus 10C has been stopped for a longer period of time than the first gas production apparatus 10A. Therefore, the control device 35 operates the third gas production apparatus 10C, which has been stopped for the longest period of time among the three gas production apparatuses 10. Therefore, after operating the third gas production apparatus 10C, the control device 35 then operates the first gas production apparatus 10A.

[0066] Subsequently, when the control device 35 receives a signal from the external control device 36 indicating that the flow rate of the hydrogen gas supplied from the single gas supply source A1 is equal to or greater than the predetermined flow rate Qx, the control device 35 operates all three gas production devices 10.

[0067] Next, suppose that the control device 35 receives a signal from the external control device 36 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx and is greater than the first predetermined flow rate Qx1. In response, the control device 35 stops the first gas production apparatus 10A while continuing the operation of the second gas production apparatus 10B and the third gas production apparatus 10C in order to preferentially operate the gas production apparatus 10 that has been stopped for the longest time among the three gas production apparatuses 10. Then, after a predetermined time has elapsed, the control device 35 operates the first gas production apparatus 10A and stops the second gas production apparatus 10B.

[0068] In this way, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production system 1 sequentially switches between the specific gas production apparatus 10 to be operated among the three gas production apparatuses 10 at specified time intervals.

[0069] [Effects of the first embodiment] The first embodiment can provide the following effects. (1-1) When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production system 1 sequentially switches a specific gas production device 10 to be operated among the multiple gas production devices 10. This makes it possible to avoid a state in which the regeneration process is not performed in the first adsorption column 11 and the second adsorption column 12 for a long period of time. This makes it possible to prevent the moisture amounts of the first adsorbent 13 and the second adsorbent 14 from reaching an equilibrium state in the first adsorption column 11 and the second adsorption column 12. This makes it possible to avoid a problem in which, for example, when the flow rate of hydrogen gas supplied from the single gas supply source A1 becomes relatively high, the moisture amounts of the first adsorbent 13 and the second adsorbent 14 reach an equilibrium state, making it difficult to sufficiently perform the adsorption process. This makes it possible to avoid, for example, a problem in which a gas other than hydrogen gas needs to be supplied into the first adsorption column 11 and the second adsorption column 12 for the purpose of regenerating the first adsorbent 13 and the second adsorbent 14.

[0070] (1-2) When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production system 1 sequentially switches between specific gas production apparatuses 10 to be operated among the multiple gas production apparatuses 10 at regular intervals. This configuration is suitable for avoiding a long period of time in which the regeneration process is not performed in the first adsorption column 11 and the second adsorption column 12, since the specific gas production apparatuses 10 can be sequentially switched between without providing a separate sensor or the like.

[0071] (1-3) When the flow rate of the single gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production system 1 preferentially operates the gas production apparatus 10 that has been stopped for the longest time among the multiple gas production apparatuses 10. This configuration is suitable for avoiding a long period of time in which the regeneration process is not performed in the first adsorption column 11 and the second adsorption column 12.

[0072] (1-4) According to the gas production system 1 of the present embodiment, it is possible to perform maintenance on the gas production apparatus 10 while the gas production apparatus 10 is stopped. As a result, it is possible to perform maintenance on each gas production apparatus 10 without stopping the entire gas production system 1, and therefore it is possible to improve the maintainability of the gas production apparatus 10 while improving the gas production efficiency.

[0073] (1-5) According to the gas production system 1 of this embodiment, even if a problem occurs in one of the gas production apparatuses 10, dry gas can be produced by the other gas production apparatuses 10. Therefore, even if a problem occurs in one of the gas production apparatuses 10, the production of dry gas can be continued without shutting down the entire gas production system 1, thereby improving gas production efficiency.

[0074] [Second embodiment] A second embodiment of the gas production apparatus will be described below with reference to Fig. 6 to Fig. 10. In the embodiment described below, the same components as those in the first embodiment already described are denoted by the same reference numerals, and duplicated descriptions thereof will be omitted or simplified.

[0075] <Gas manufacturing equipment> As shown in FIG. 6, the gas production apparatus 50 includes three first adsorption columns 51. The gas production apparatus 50 includes three second adsorption columns 52. Each first adsorption column 51 is an adsorption column that houses a first adsorbent 53 as an adsorbent therein. Each second adsorption column 52 is an adsorption column that houses a second adsorbent 54 as an adsorbent therein. Thus, the gas production apparatus 50 includes three or more adsorption columns. Each first adsorbent 53 and each second adsorbent 54 are configured to be capable of adsorbing moisture. Examples of each first adsorbent 53 and each second adsorbent 54 include activated alumina, silica gel, and synthetic zeolite. The gas production apparatus 50 produces dry gas by adsorbing moisture contained in hydrogen gas with each first adsorbent 53 or each second adsorbent 54.

[0076] In the following description, each of the first adsorption columns 51 may be referred to as "first adsorption column 51A," "first adsorption column 51B," or "first adsorption column 51C." In the following description, each of the second adsorption columns 52 may be referred to as "second adsorption column 52A," "second adsorption column 52B," or "second adsorption column 52C."

[0077] The gas production apparatus 50 includes a supply pipe 55, an exhaust pipe 56, a regeneration pipe 57, and a reflux pipe 58. The supply pipe 55 is connected to a single gas supply source A1. The exhaust pipe 56 is connected to a supply target (not shown) of the dry gas produced by the gas production apparatus 50. The regeneration pipe 57 branches off from the supply pipe 55. The reflux pipe 58 is connected to the supply pipe 55.

[0078] The gas production device 50 includes three first pipes 61, three second pipes 62, and three third pipes 63. A first end of each of the first pipes 61 is connected to the supply pipe 55. Each of the first pipes 61 is connected in parallel to the supply pipe 55. The hydrogen gas flowing through the supply pipe 55 branches into each of the first pipes 61.

[0079] A first end of each second pipe 62 and a first end of each third pipe 63 are connected to the second end of each first pipe 61. Thus, each second pipe 62 and each third pipe 63 branches off from the second end of each first pipe 61. A second end of each second pipe 62 is connected to the first port 51a of each first adsorption cylinder 51. A second end of each third pipe 63 is connected to the first port 52a of each second adsorption cylinder 52.

[0080] The gas production device 50 has three fourth pipes 64, three fifth pipes 65, and three sixth pipes 66. The first end of each fourth pipe 64 is connected to the second port 51b of each first adsorption cylinder 51. The first end of each fifth pipe 65 is connected to the second port 52b of each second adsorption cylinder 52. The first end of each sixth pipe 66 is connected to the second end of each fourth pipe 64 and the second end of each fifth pipe 65. Therefore, each fourth pipe 64 and each fifth pipe 65 merge into each sixth pipe 66. The second end of each sixth pipe 66 is connected to the discharge pipe 56. In each sixth pipe 66, dry gas produced by adsorbing moisture contained in hydrogen gas by each first adsorbent 53 or each second adsorbent 54 flows. The second end of each sixth pipe 66 is connected in parallel to the discharge pipe 56. The dry gas flowing through each of the sixth pipes 66 joins the exhaust pipe 56 .

[0081] The gas production apparatus 50 includes three seventh pipes 67. A first end of each of the seventh pipes 67 is connected to the regeneration pipe 57. Each of the seventh pipes 67 is connected in parallel to the regeneration pipe 57. Therefore, each of the seventh pipes 67 branches off from the regeneration pipe 57. A second end of each of the seventh pipes 67 is connected to a junction of each of the fourth pipes 64 and each of the fifth pipes 65 with each of the sixth pipes 66. Each of the seventh pipes 67 is provided with a heating unit 71. Each of the heating units 71 is an electric heater that heats a portion of each of the seventh pipes 67 from the surroundings.

[0082] The gas production apparatus 50 includes three eighth pipes 68. A first end of each of the eighth pipes 68 is connected to a branch point of each of the second pipes 62 and each of the third pipes 63 from each of the first pipes 61. A second end of each of the eighth pipes 68 is connected to the reflux pipe 58. Each of the eighth pipes 68 is connected in parallel to the reflux pipe 58. The hydrogen gas flowing through each of the eighth pipes 68 merges into the reflux pipe 58.

[0083] Each eighth pipe 68 is provided with a cooling unit 72. The cooling unit 72 is a water-cooled cooler. Each cooling unit 72 is configured to be able to cool the hydrogen gas flowing through each eighth pipe 68. Each eighth pipe 68 is provided with a drain collection unit 73. Each drain collection unit 73 is provided in a portion of each eighth pipe 68 closer to the reflux pipe 58 than the cooling unit 72. Each drain collection unit 73 is configured to be able to collect moisture contained in the hydrogen gas flowing through each eighth pipe 68.

[0084] The gas production device 50 includes three first switching valves 81. Each first switching valve 81 is provided at a connection point where each first pipe 61, each second pipe 62, each third pipe 63, and each eighth pipe 68 all join together. Each first switching valve 81 is a four-way valve. Each first switching valve 81 has a first port 81a, a second port 81b, a third port 81c, and a fourth port 81d. The first port 81a of each first switching valve 81 is connected to a second end of each first pipe 61. The second port 81b of each first switching valve 81 is connected to a first end of each second pipe 62. The third port 81c of each first switching valve 81 is connected to a first end of each third pipe 63. The fourth port 81d of each first switching valve 81 is connected to a first end of each eighth pipe 68.

[0085] Each first switching valve 81 is configured to be switchable to a first switching state in which the first port 81a communicates with the second port 81b and the third port 81c communicates with the fourth port 81d. Also, each first switching valve 81 is configured to be switchable to a second switching state in which the first port 81a communicates with the third port 81c and the second port 81b communicates with the fourth port 81d.

[0086] The gas production device 50 includes three second switching valves 82. Each second switching valve 82 is provided at a connection point where each of the fourth pipes 64, the fifth pipes 65, the sixth pipes 66, and the seventh pipes 67 all join together. Each second switching valve 82 is a four-way valve. Each second switching valve 82 has a first port 82a, a second port 82b, a third port 82c, and a fourth port 82d. The first port 82a of each second switching valve 82 is connected to the second end of each of the fourth pipes 64. The second port 82b of each second switching valve 82 is connected to the second end of each of the fifth pipes 65. The third port 82c of each second switching valve 82 is connected to the first end of each of the sixth pipes 66. The fourth port 82d of each second switching valve 82 is connected to the second end of the seventh pipe 67.

[0087] Each second switching valve 82 is configured to be switchable to a first switching state in which the first port 82a communicates with the third port 82c and the second port 82b communicates with the fourth port 82d. Also, each second switching valve 82 is configured to be switchable to a second switching state in which the first port 82a communicates with the fourth port 82d and the second port 82b communicates with the third port 82c.

[0088] The gas production apparatus 50 includes three first on / off valves 83. Each of the first on / off valves 83 is a two-way valve. Each of the first on / off valves 83 is provided in each of the first pipes 61. When each of the first on / off valves 83 is in an open state, it allows the flow of hydrogen gas in each of the first pipes 61. On the other hand, when each of the first on / off valves 83 is in a closed state, it blocks the flow of hydrogen gas in each of the first pipes 61.

[0089] The gas production apparatus 50 includes three second on / off valves 84. Each of the second on / off valves 84 is a two-way valve. Each of the second on / off valves 84 is provided in each of the sixth pipes 66. When each of the second on / off valves 84 is in an open state, it allows the flow of hydrogen gas in each of the sixth pipes 66. On the other hand, when each of the second on / off valves 84 is in a closed state, it blocks the flow of hydrogen gas in each of the sixth pipes 66.

[0090] The gas production apparatus 50 includes three third on / off valves 85. Each third on / off valve 85 is a two-way valve. Each third on / off valve 85 is provided in a portion of each seventh pipe 67 closer to the regeneration pipe 57 than each heating section 71. Each third on / off valve 85 allows the flow of hydrogen gas in each seventh pipe 67 by being in an open state. On the other hand, each third on / off valve 85 blocks the flow of hydrogen gas in each seventh pipe 67 by being in a closed state.

[0091] The gas production apparatus 50 includes three fourth on-off valves 86. Each of the fourth on-off valves 86 is a two-way valve. Each of the fourth on-off valves 86 is provided in a portion of each of the eighth pipes 68 closer to the reflux pipe 58 than each of the drain recovery sections 73. Each of the fourth on-off valves 86 allows the flow of hydrogen gas in each of the eighth pipes 68 by being in an open state. On the other hand, each of the fourth on-off valves 86 blocks the flow of hydrogen gas in each of the eighth pipes 68 by being in a closed state.

[0092] <Electrical configuration of gas production equipment> The gas production apparatus 50 includes a control device 74. The control device 74 includes a central processing unit (CPU). The control device 74 also includes a memory including a read-only memory (ROM) that stores various programs and maps in advance, and a random access memory (RAM) that temporarily stores the results of CPU calculations, etc. The control device 74 also includes a timer counter, an input interface, an output interface, etc.

[0093] The control device 74 is electrically connected to each of the first switching valves 81, each of the second switching valves 82, each of the first on-off valves 83, each of the second on-off valves 84, each of the third on-off valves 85, and each of the fourth on-off valves 86. The control device 74 controls the driving of each of the first switching valves 81, each of the second switching valves 82, each of the first on-off valves 83, each of the second on-off valves 84, each of the third on-off valves 85, and each of the fourth on-off valves 86. The control device 74 is also electrically connected to each of the heating units 71 and each of the cooling units 72. The control device 74 controls the driving of each of the heating units 71 and each of the cooling units 72.

[0094] The control device 74 is electrically connected to an external control device 75 that controls the operation of the single gas supply source A1. The control device 74 receives a signal related to the flow rate of hydrogen gas supplied from the single gas supply source A1 from the external control device 75. The control device 74 also receives a signal from the external control device 75 that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx.

[0095] <Control of the control device> 7 and 8 show an example of control by the control device 74. As shown in Fig. 7, a first program for executing an adsorption process in each of the first adsorption columns 51 and executing a regeneration process in each of the second adsorption columns 52 is stored in advance in the control device 74. In the first program, each of the first switching valves 81 is set to a first switching state, and each of the second switching valves 82 is set to a first switching state. In the first program, each of the first on-off valves 83, each of the second on-off valves 84, each of the third on-off valves 85, and each of the fourth on-off valves 86 is set to an open state.

[0096] When the first program is being executed, the supply pipe 55, each of the first pipes 61, and each of the second pipes 62 constitute a supply line 87 that supplies hydrogen gas from the single gas supply source A1 into each of the first adsorption columns 51. In the adsorption step of the first program, moisture contained in the hydrogen gas supplied from the single gas supply source A1 through the supply line 87 into each of the first adsorption columns 51 is adsorbed by the first adsorbent 53. In this way, the gas production apparatus 50 produces dry gas by adsorbing moisture by each of the first adsorbents 53 in the adsorption step.

[0097] When the first program is being executed, the regeneration piping 57, each of the seventh piping 67, and each of the fifth piping 65 form a regeneration supply line 88 that branches off from the supply line 87 and supplies a portion of the hydrogen gas flowing through the supply line 87 into each of the second adsorption columns 52, which are the targets for which the regeneration process is to be performed.

[0098] In the regeneration step of the first program, a portion of the hydrogen gas flowing through the supply line 87 is heated by the heating unit 71 and then supplied into each second adsorption column 52 which is the target for executing the regeneration step. Then, in the first program, the second adsorbent 54 in each second adsorption column 52 which is the target for executing the regeneration step is regenerated. Therefore, in the regeneration step of the first program, the moisture contained in each second adsorbent 54 is removed after the adsorption step to regenerate each second adsorbent 54.

[0099] When the first program is being executed, the third pipes 63, the eighth pipes 68, and the reflux pipe 58 constitute a regeneration reflux line 89 that refluxes the hydrogen gas discharged from each second adsorption column 52 during the regeneration process to the supply line 87. In the first program, the hydrogen gas discharged from each second adsorption column 52 during the regeneration process is cooled by each cooling unit 72, and the moisture contained in the hydrogen gas is recovered by each drain recovery unit 73, and then the hydrogen gas is refluxed to the supply line 87.

[0100] 8, a second program for executing a regeneration process in each of the first adsorption columns 51 and an adsorption process in each of the second adsorption columns 52 is prestored in the control device 74. In the second program, each of the first switching valves 81 is set to the second switching state, and each of the second switching valves 82 is set to the second switching state. In the second program, each of the first on-off valves 83, each of the second on-off valves 84, each of the third on-off valves 85, and each of the fourth on-off valves 86 is set to an open state.

[0101] When the second program is being executed, the supply pipe 55, each of the first pipes 61, and each of the third pipes 63 form a supply line 87 that supplies hydrogen gas from the single gas supply source A1 into each of the second adsorption columns 52.

[0102] In the adsorption step of the second program, moisture contained in the hydrogen gas supplied from the single gas supply source A1 through the supply line 87 into each of the second adsorption columns 52 is adsorbed by each of the second adsorbents 54. In this manner, the gas production apparatus 50 produces dry gas by adsorbing moisture by each of the second adsorbents 54 in the adsorption step.

[0103] When the second program is being executed, the regeneration piping 57, each of the seventh piping 67, and each of the fourth piping 64 form a regeneration supply line 88 that branches off from the supply line 87 and supplies a portion of the hydrogen gas flowing through the supply line 87 into each of the first adsorption columns 51, which are the targets for which the regeneration process is to be performed.

[0104] In the regeneration step of the second program, a portion of the hydrogen gas flowing through the supply line 87 is heated by each heating unit 71 and then supplied into each first adsorption column 51 which is the target for executing the regeneration step. Then, in the second program, the first adsorbent 53 in each first adsorption column 51 which is the target for executing the regeneration step is regenerated. Therefore, in the regeneration step of the second program, the moisture contained in each first adsorbent 53 is removed after the adsorption step to regenerate each first adsorbent 53.

[0105] When the second program is being executed, the second pipes 62, the eighth pipes 68, and the reflux pipe 58 form a regeneration reflux line 89 that refluxes the hydrogen gas discharged from each of the first adsorption columns 51 during the regeneration process to the supply line 87. In the second program, the hydrogen gas discharged from each of the first adsorption columns 51 during the regeneration process is cooled by each of the cooling units 72, and the moisture contained in the hydrogen gas is recovered by each of the drain recovery units 73, and then the hydrogen gas is refluxed to the supply line 87.

[0106] The control device 74 stores in advance a program for switching to the second program after a certain time has elapsed since switching to the first program. The "certain time" is the time it is estimated that the moisture contained in the second adsorbent 54 in each second adsorption column 52 has been sufficiently desorbed. This "certain time" is determined in advance by experiment or the like.

[0107] The control device 74 stores in advance a program for switching to the first program after a certain time has elapsed since switching to the second program. The "certain time" is the time it is estimated that the moisture contained in the first adsorbent 53 in each first adsorption column 51 has been sufficiently desorbed. This "certain time" is determined in advance by an experiment or the like.

[0108] In this way, the gas production apparatus 50 produces dry gas by alternately and repeatedly performing the adsorption process and the regeneration process in each of the first adsorption cylinders 51 and each of the second adsorption cylinders 52, thereby adsorbing moisture with each of the first adsorbents 53 and each of the second adsorbents 54 in the adsorption process. Therefore, the gas production apparatus 50 includes a plurality of adsorption cylinders so that the adsorption process can be performed in another adsorption cylinder until the adsorption process is performed again in the adsorption cylinder that contains the adsorbent after the adsorption process and the adsorption process is regenerated in the regeneration process.

[0109] 9, the control device 74 stores in advance a program for controlling the operation of each of the first switch valves 81 and each of the second switch valves 82 based on the flow rate of hydrogen gas supplied from the single gas supply source A1. The control device 74 also stores in advance a program for controlling the operation of each of the first on / off valves 83, each of the second on / off valves 84, each of the third on / off valves 85, and each of the fourth on / off valves 86 based on the flow rate of hydrogen gas supplied from the single gas supply source A1.

[0110] In addition, in Fig. 9, the first on-off valve 83, the second on-off valve 84, the third on-off valve 85, and the fourth on-off valve 86 corresponding to the first adsorption column 51A and the second adsorption column 52A are in an open state. Furthermore, the first on-off valves 83, the second on-off valves 84, the third on-off valves 85, and the fourth on-off valves 86 corresponding to the other first adsorption column 51 and second adsorption column 52 are in a closed state. In Fig. 9, the first switching valve 81 and the second switching valve 82 corresponding to the first adsorption column 51A and the second adsorption column 52A are in the second switching state. Therefore, in Fig. 9, the regeneration process is being performed in the first adsorption column 51A and the adsorption process is being performed in the second adsorption column 52A, and neither the adsorption process nor the regeneration process is being performed in the other first adsorption column 51 and second adsorption column 52.

[0111] The table shown in FIG. 10 indicates whether each of the first adsorption columns 51A, 51B, 51C and the second adsorption columns 52A, 52B, 52C is undergoing an adsorption process, whether each of the first adsorption columns 51A, 51B, 51C and the second adsorption columns 52A, 52B, 52C is undergoing a regeneration process, or whether neither the adsorption process nor the regeneration process is being performed.

[0112] As shown in Fig. 10, the control device 74 stores a program for causing the first adsorption columns 51A, 51B, and 51C and the second adsorption columns 52A, 52B, and 52C to perform an adsorption process and then a regeneration process, respectively. When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the control device 74 sequentially switches between specific adsorption columns for performing an adsorption process and then a regeneration process in the first adsorption columns 51A, 51B, and 51C and the second adsorption columns 52A, 52B, and 52C. Therefore, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production device 50 sequentially switches between specific adsorption columns for performing an adsorption process and then a regeneration process in three or more adsorption columns.

[0113] When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the control device 74 sequentially switches between specific adsorption tubes that perform the adsorption process and the regeneration process in the first adsorption tubes 51A, 51B, 51C and the second adsorption tubes 52A, 52B, 52C at regular intervals. Therefore, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate, the gas production device 50 sequentially switches between specific adsorption tubes that perform the adsorption process and the regeneration process in three or more adsorption tubes at regular intervals. The "specified time" refers to a predetermined time that has elapsed since the adsorption process began in the first adsorption tubes 51A, 51B, 51C and the second adsorption tubes 52A, 52B, 52C.

[0114] When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the control device 74 preferentially causes the first adsorption tubes 51A, 51B, 51C and the second adsorption tubes 52A, 52B, 52C that have not been performing the adsorption process or the regeneration process for the longest time to perform the adsorption process and the regeneration process. Therefore, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the gas production device 50 preferentially causes the adsorption tube that has not been performing the adsorption process or the regeneration process for the longest time to perform the adsorption process and the regeneration process among the three or more adsorption tubes. The control device 74 measures the time during which neither the adsorption process nor the regeneration process is performed in the first adsorption tubes 51A, 51B, 51C and the second adsorption tubes 52A, 52B, 52C using a timer.

[0115] [Operation of the second embodiment] Next, the operation of the second embodiment will be described. For example, the control device 74 receives a signal from the external control device 75 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx and is equal to or less than a first predetermined flow rate Qx1, which is a flow rate less than the predetermined flow rate Qx. Then, the control device 74 controls the drive of each of the first switching valves 81, the second switching valves 82, the first on-off valves 83, the second on-off valves 84, the third on-off valves 85, and the fourth on-off valves 86 so that one of the first adsorption columns 51A, 51B, 51C and the second adsorption columns 52A, 52B, 52C becomes a specific adsorption column that performs an adsorption process and then a regeneration process. Then, the control device 74 sequentially switches between the specific adsorption columns that perform an adsorption process and then a regeneration process in the first adsorption columns 51A, 51B, 51C and the second adsorption columns 52A, 52B, 52C.

[0116] Also, it is assumed that the controller 74 receives a signal from the external control device 75 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is equal to or greater than the predetermined flow rate Qx. The controller 74 then controls the operation of the first switching valves 81, the second switching valves 82, the first on / off valves 83, the second on / off valves 84, the third on / off valves 85, and the fourth on / off valves 86 so that the adsorption process is performed in three of the first adsorption columns 51A, 51B, and 51C and the second adsorption columns 52A, 52B, and 52C. Then, the adsorption column in which the adsorption process has been performed switches to the regeneration process after a certain time has elapsed, and the other adsorption columns switch to the adsorption process.

[0117] Assume that the control device 74 receives a signal from the external control device 75 indicating that the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx and is greater than the first predetermined flow rate Qx1. Then, the control device 74 controls the operation of the first switching valves 81, the second switching valves 82, the first on / off valves 83, the second on / off valves 84, the third on / off valves 85, and the fourth on / off valves 86 so that the adsorption process is performed in two of the first adsorption columns 51A, 51B, and 51C and the second adsorption columns 52A, 52B, and 52C. Then, the adsorption column that has been subjected to the adsorption process switches to the regeneration process after a certain time has elapsed, and the other two adsorption columns switch to the adsorption process.

[0118] In this manner, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production apparatus 50 sequentially switches between specific adsorption columns to perform an adsorption process and then a regeneration process in the adsorption columns.

[0119] [Effects of the second embodiment] The second embodiment can provide the following effects. (2-1) When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production device 50 sequentially switches between specific adsorption columns in which the adsorption process is performed in each of the first adsorption columns 51 and each of the second adsorption columns 52 and the regeneration process is performed after the adsorption process is performed in each of the first adsorption columns 51 and each of the second adsorption columns 52. This makes it possible to avoid a situation in which the regeneration process is not performed in each of the first adsorption columns 51 and each of the second adsorption columns 52 continues for a long period of time. This makes it possible to prevent the moisture amounts of the first adsorbents 53 and the second adsorbents 54 from reaching an equilibrium state in each of the first adsorption columns 51 and each of the second adsorption columns 52. This makes it possible to avoid a problem in which, for example, when the flow rate of hydrogen gas supplied from the single gas supply source A1 becomes relatively high, the moisture amounts of the first adsorbents 53 and each of the second adsorbents 54 reach an equilibrium state, making it difficult to sufficiently perform the adsorption process. Therefore, for example, there is no need to supply a gas other than hydrogen gas into each of the first adsorption columns 51 and each of the second adsorption columns 52 for the purpose of regenerating each of the first adsorbents 53 and each of the second adsorbents 54, which makes it possible to avoid deterioration in the start-up of the gas production apparatus 50. As a result, the gas production efficiency can be improved.

[0120] (2-2) When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production apparatus 50 sequentially switches between specific adsorption columns that perform an adsorption process and then a regeneration process in each of the first adsorption columns 51 and each of the second adsorption columns 52 at regular intervals. This configuration is suitable for avoiding a long period of time in which the regeneration process is not performed in each of the first adsorption columns 51 and each of the second adsorption columns 52, since it is possible to sequentially switch between specific adsorption columns that perform an adsorption process and then a regeneration process without providing a separate sensor or the like.

[0121] (2-3) When the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, the gas production apparatus 50 preferentially causes the adsorption column that has not been performing either the adsorption process or the regeneration process to be performed in the longest time among the first adsorption columns 51 and the second adsorption columns 52. This configuration is suitable for avoiding a long period of time in which the regeneration process is not being performed in each of the first adsorption columns 51 and the second adsorption columns 52.

[0122] (2-4) According to the gas production apparatus 50 of this embodiment, it is possible to perform maintenance on the adsorption columns that are not performing either the adsorption process or the regeneration process in each of the first adsorption columns 51 and each of the second adsorption columns 52. As a result, it is possible to perform maintenance on each of the adsorption columns without shutting down the entire gas production apparatus 50, and therefore it is possible to improve the maintainability of the gas production apparatus 50 while improving the gas production efficiency.

[0123] (2-5) According to the gas production apparatus 50 of this embodiment, even if a problem occurs in one of the first adsorption columns 51 and the second adsorption columns 52, dry gas can be produced by the remaining first adsorption columns 51 and the second adsorption columns 52. Therefore, even if a problem occurs in one of the first adsorption columns 51 and the second adsorption columns 52, dry gas can be continued to be produced without having to stop the entire gas production apparatus 50, thereby improving gas production efficiency.

[0124] [Example of change] The above-described embodiments may be modified as follows: The above-described embodiments and the following modifications may be combined with each other to the extent that no technical contradiction occurs.

[0125] In the first embodiment, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, for example, a specific gas production apparatus 10 to be operated among the multiple gas production apparatuses 10 may be switched in sequence based on a dew point measured by a dew point meter provided at the outlet of the adsorption column during the regeneration process. For example, a specific gas production apparatus 10 to be operated among the multiple gas production apparatuses 10 may be switched in sequence when the dew point reaches a value estimated to be the point at which moisture is completely removed from the adsorbent during the regeneration process.

[0126] In the first embodiment, when the flow rate of the hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, the gas production apparatus 10 that has been stopped for the longest time among the multiple gas production apparatuses 10 does not need to be preferentially operated.

[0127] In the second embodiment, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than a predetermined flow rate Qx, for example, based on the dew point measured by a dew point meter provided at the outlet of the adsorption column during the regeneration process, the first adsorption column 51 and the second adsorption column 52 may be caused to perform the adsorption process and then sequentially switched to a specific adsorption column for performing the regeneration process. For example, when the dew point reaches a point at which moisture is estimated to have completely desorbed from the adsorbent during the regeneration process, the first adsorption column 51 and the second adsorption column 52 may be caused to perform the adsorption process and then sequentially switched to a specific adsorption column for performing the regeneration process.

[0128] In the second embodiment, when the flow rate of hydrogen gas supplied from the single gas supply source A1 is less than the predetermined flow rate Qx, it is not necessary to preferentially cause the adsorption tube that has not been performing either the adsorption process or the regeneration process for the longest time among the first adsorption tubes 51 and the second adsorption tubes 52 to perform both the adsorption process and the regeneration process.

[0129] In the first embodiment, the gas production system 1 may include a flow sensor that detects the flow rate of hydrogen gas flowing through the supply piping 2. The flow rate of hydrogen gas flowing through the supply piping 2 is the flow rate of hydrogen gas supplied from the single gas supply source A1. When the flow rate of hydrogen gas detected by the flow sensor is less than a predetermined flow rate Qx, the control device 35 may sequentially switch between specific gas production devices 10 to be operated among the multiple gas production devices 10.

[0130] In the second embodiment, a flow sensor may be provided to detect the flow rate of hydrogen gas flowing in a portion of the supply piping 55 closer to the single gas supply source A1 than the connection point with the regeneration piping 57. The flow rate of hydrogen gas flowing in the portion of the supply piping 55 closer to the single gas supply source A1 than the connection point with the regeneration piping 57 is the flow rate of hydrogen gas supplied from the single gas supply source A1. When the flow rate of hydrogen gas detected by the flow sensor is less than a predetermined flow rate Qx, the control device 74 may cause each of the first adsorption columns 51 and each of the second adsorption columns 52 to perform an adsorption process, and then sequentially switch between specific adsorption columns to perform the regeneration process.

[0131] In each of the above embodiments, the heating sections 22 and 71 do not have to be electric heaters and may be, for example, steam heaters. In each of the above-described embodiments, the cooling units 24, 72 do not have to be water-cooled coolers, and may be, for example, air-cooled coolers.

[0132] In the first embodiment, the number of gas production devices 10 may be two, or may be four or more. In the second embodiment, the number of first adsorption columns 51 and the number of second adsorption columns 52 are not particularly limited as long as the total number of first adsorption columns 51 and second adsorption columns 52 is three or more.

[0133] In the first embodiment, the first switching valve 31, the second switching valve 32, the first on-off valve 41, and the second on-off valve 42 may be manually controlled instead of electrically controlled. In the second embodiment, the first switching valves 81, the second switching valves 82, the first on / off valves 83, the second on / off valves 84, the third on / off valves 85, and the fourth on / off valves 86 may be manually controlled rather than electrically controlled.

[0134] In the first embodiment, the gas production system 1 may, for example, adsorb moisture contained in oxygen gas, which is a single gas, to produce a dry gas. In short, the single gas is not limited to hydrogen gas.

[0135] In the second embodiment, the gas production device 50 may adsorb moisture contained in oxygen gas, which is a single gas, to produce a dry gas. In short, the single gas is not limited to hydrogen gas. [Explanation of symbols]

[0136] 1...gas production system, 10,50...gas production apparatus, 11,51...first adsorption column which is an adsorption column, 12,52...second adsorption column which is an adsorption column, 13,53...first adsorbent as an adsorbent, 14,54...second adsorbent as an adsorbent, 22,71...heating section, 24,72...cooling section, 43,87...supply line, A1...single gas supply source.

Claims

1. Equipped with multiple gas production equipment, Each of the gas production devices is An adsorption cylinder that contains an adsorbent therein, an adsorption step of adsorbing moisture contained in a single gas supplied from a single gas supply source into the adsorption cylinder through a supply line with the adsorbent, and a regeneration step of desorbing moisture contained in the adsorbent after the adsorption step to regenerate the adsorbent, the adsorption step being repeated alternately in the adsorption cylinder, thereby producing a dry gas by adsorbing moisture with the adsorbent in the adsorption step; a plurality of adsorption cylinders are provided so that the adsorption step can be carried out in another adsorption cylinder until the adsorption step is carried out again in the adsorption cylinder containing the adsorbent after the adsorption step by regenerating the adsorbent in the regeneration step; In the regeneration step, a portion of the single gas flowing through the supply line is heated by a heating unit and then supplied into an adsorption column which is a target for carrying out the regeneration step, and the single gas discharged from the adsorption column during the regeneration step is cooled by a cooling unit to recover moisture contained in the single gas, and then the single gas is returned to the supply line, A gas production system comprising: a gas production apparatus that sequentially switches between a specific gas production apparatus to be operated among the plurality of gas production apparatuses when a flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate.

2. 2. The gas manufacturing system according to claim 1, wherein when the flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the specific gas manufacturing device to be operated among the plurality of gas manufacturing devices is sequentially switched every time a specified time has elapsed.

3. 3. The gas manufacturing system according to claim 1, wherein when a flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the gas manufacturing apparatus having the longest downtime among the plurality of gas manufacturing apparatuses is operated preferentially.

4. An adsorption cylinder that contains an adsorbent therein, an adsorption step of adsorbing moisture contained in a single gas supplied from a single gas supply source into the adsorption cylinder through a supply line with the adsorbent, and a regeneration step of desorbing moisture contained in the adsorbent after the adsorption step to regenerate the adsorbent, the adsorption step being repeated alternately in the adsorption cylinder, thereby producing a dry gas by adsorbing moisture with the adsorbent in the adsorption step; three or more adsorption columns are provided so that the adsorption step can be carried out in another adsorption column until the adsorption step is carried out again in the adsorption column containing the adsorbent after the adsorption step by regenerating the adsorbent in the regeneration step, In the gas production apparatus, in the regeneration step, a portion of the single gas flowing through the supply line is heated by a heating unit and then supplied into an adsorption column which is a target for carrying out the regeneration step, and the single gas discharged from the adsorption column during the regeneration step is cooled by a cooling unit to recover moisture contained in the single gas, and then the single gas is returned to the supply line, a gas production apparatus comprising: a first adsorption column for performing the adsorption process in the three or more adsorption columns and then a second adsorption column for performing the regeneration process in the three or more adsorption columns;

5. 5. The gas manufacturing apparatus according to claim 4, wherein, when a flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, the adsorption process is performed in the three or more adsorption columns, and then a specific adsorption column in which the regeneration process is performed is sequentially switched every time a specified time has elapsed.

6. 6. The gas production apparatus according to claim 4, wherein, when a flow rate of the single gas supplied from the single gas supply source is less than a predetermined flow rate, an adsorption tube that has not been subjected to either the adsorption process or the regeneration process for the longest period of time among the three or more adsorption tubes is preferentially caused to perform the adsorption process and the regeneration process.

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