JP2010280535A - Apparatus, method and program for producing hydrogen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen producing technique efficiently purifying hydrogen from a hydrogen-mixed gas containing a hydrocarbon gas and an inorganic gas. <P>SOLUTION: The hydrogen producing apparatus 10 includes: first on-off valves 22 (22A, 22B, 22C) for making the hydrogen mixed gas flow from a hydrogen producing part 11; first adsorption columns 21 (21A, 21B, 21C) connected to a first flow path 17 in parallel to adsorb the hydrocarbon gas component contained in the hydrogen mixed gas; second on-off valves 32 (32A, 32B, 32C) for making the hydrogen mixed gas flow; second adsorption columns 31 (31A, 31B, 31C) connected to a second flow path 18 in parallel to adsorb the inorganic gas component contained in the hydrogen mixed gas; and heating medium on-off valves 23A, 23B, 23C, 33A, 33B, 33C for passing a heating medium through the first adsorption columns 21 or the second adsorption columns 31 in which the flow of the hydrogen mixed gas is stopped by the fact that the first on-off valves 22 or the second on-off valves 32 changes the flow direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hydrogen production technique using a hydrocarbon compound such as dimethyl ether (hereinafter referred to as DME) as a raw material.

Currently, the practical use of fuel cells or power devices using hydrogen as an energy source is being promoted, and several promising hydrogen production methods have been proposed.
Especially, the hydrogen production method by steam reforming of dimethyl ether (DME) is preferable in that hydrogen can be generated at a low temperature of 400 ° C. or lower.
In addition, since the raw material DME is a chemically synthesized product, it does not contain impurities such as sulfur, which is a problem when natural gas or liquefied petroleum gas is used as a raw material, and it is not necessary to remove these impurities. It is suitable (for example, Patent Document 1).
Furthermore, the ability to generate hydrogen at a low reaction temperature of 400 ° C. or lower enables the use of waste heat from a nuclear power plant and reduces hydrogen production costs (for example, Patent Document 2).

And when using hydrogen as fuels, such as a fuel cell, it is necessary to refine | purify the generated hydrogen and to make it high purity hydrogen of 99.99% or more.
For this reason, a process of purifying hydrogen by removing carbon dioxide or the like, which is a byproduct accompanying steam reforming of DME, is essential (for example, Patent Document 3).
As a method for purifying hydrogen in such a high purity, a PSA (pressure swing adsorption) method is generally used.
In this PSA method, impurities are adsorbed on the adsorbent to increase the hydrogen purity. When the adsorbent is filled with impurities, the pressure is lowered to desorb the impurities from the adsorbent to restore the function of the adsorbent. This is a technique for repeatedly and continuously obtaining high-purity hydrogen.

JP 2005-170707 A JP 2008-273895 A JP 2008-247632 A

By the way, in the hydrogen mixed gas manufactured based on patent document 1, 2, unreacted DME, methane, carbon monoxide, etc. are contained in addition to the carbon dioxide which is a by-product.
Further, in the hydrogen purification method based on Patent Document 3, the inorganic gas component contained in the hydrogen mixed gas is to be removed, and the removal of the hydrocarbon gas component (unreacted DME) is unexpected.
When a hydrogen mixed gas containing a hydrocarbon gas component such as unreacted DME is supplied to a hydrogen purification technique such as Patent Document 3, the hydrocarbon gas component is strongly adsorbed by the adsorbent inside the system. There is a problem that its functional recovery becomes difficult.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hydrogen production technique for efficiently purifying hydrogen from a hydrogen mixed gas containing a hydrocarbon gas component and an inorganic gas component.

  A hydrogen production apparatus according to the present invention includes a first on-off valve that causes a hydrogen mixed gas output from a hydrogen generation unit that uses a hydrocarbon-based compound as a raw material to flow in any direction branched from a first flow path, A first adsorption tower that is connected in parallel to each branch of one flow path and adsorbs a hydrocarbon gas component contained in the hydrogen mixed gas, and a hydrogen mixed gas output from the first adsorption tower is branched to the second flow path A second on-off valve that flows in either direction, a second adsorption tower that is connected in parallel to each branch of the second flow path and adsorbs an inorganic gas component contained in the hydrogen mixed gas, and the first on-off valve After the valve or the second opening / closing valve switches the flow direction, the heating medium opening / closing valve that allows the heating medium to pass through the first adsorption tower or the second adsorption tower in which the hydrogen mixed gas has flowed before the switching. And characterized by comprising

  ADVANTAGE OF THE INVENTION According to this invention, the hydrogen production technique which refine | purifies hydrogen efficiently from the hydrogen mixed gas containing a hydrocarbon gas component and an inorganic gas component is provided.

1 is a block diagram showing an embodiment of a hydrogen production apparatus according to the present invention. The schematic sectional drawing of the 1st adsorption tower which removes a hydrocarbon gas component in this embodiment. The schematic sectional drawing of the 2nd adsorption tower which removes an inorganic gas component in this embodiment. The flowchart which shows embodiment of the hydrogen production method which concerns on this invention. The adsorption characteristic graph of DME which shows the example and comparative example of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, the hydrogen production apparatus 10 includes a hydrogen generation unit 11, a first flow channel 17, a first purification unit 20, a second flow channel 18, a second purification unit 30, and a hydrogen accumulation unit 12. And a heat medium source 13.
In the hydrogen production apparatus 10 configured as described above, the hydrogen mixed gas generated in the hydrogen generation unit 11 is introduced into the first purification unit 20 via the first flow path 17. Then, in the process of flowing through the first purification unit 20, an impurity component (hydrocarbon gas component) having a large molecular weight contained in the hydrogen mixed gas is removed.
The hydrogen mixed gas that has passed through the first purification unit 20 is introduced into the second purification unit 30 via the second flow path 18. Then, in the process of flowing through the second purification unit 30, an impurity component (inorganic gas component) having a low molecular weight contained in the hydrogen mixed gas is removed.
Thus, impurity components are removed from the hydrogen mixed gas, and purified high-purity hydrogen gas accumulates in the hydrogen accumulation unit 12.

By the way, a plurality of first adsorption towers 21 (21A, 21B, 21C) are connected in parallel to the first purification section 20, and a plurality of second adsorption towers 31 (31A, 31B, 31C) are connected to the second purification section 30. Are connected in parallel.
And the hydrogen mixed gas which flows toward the hydrogen storage part 12 from the hydrogen generation part 11 passes through any one 1st adsorption tower 21 and the 2nd adsorption tower 31, and is refine | purified to high purity hydrogen gas. Moreover, if the impurity component which adsorb | sucked by the hydrogen gas mixture flowing continuously is accumulated, the adsorption function of the first adsorption tower 21 and the second adsorption tower 31 is lowered. Then, the 1st flow path 17 and the 2nd flow path 18 switch the flow direction of hydrogen mixed gas, and let it pass through the different 1st adsorption tower 21 and the 2nd adsorption tower 31 which are different.
Then, the adsorption function of the first adsorption tower 21 and the second adsorption tower 31 whose adsorption function is reduced by adsorbing the impurity component of the hydrogen mixed gas is restored by the heat medium supplied from the heat medium source 13.

The hydrogen generating unit 11 generates a hydrogen mixed gas using a hydrocarbon compound as a raw material. As shown in the reaction formula (1), this hydrogen generation process includes a dimethyl ether (DME) raw material by steam reforming, but is not limited thereto, and a hydrocarbon compound is used as a raw material. If it does, it can use suitably.
Since DME as a raw material is chemically synthesized from methane based on reaction formula (2), it contains unreacted methane and carbon monoxide based on side reaction formula (3). .
For this reason, the hydrogen mixed gas output from the hydrogen generator 11 contains unreacted DME, methane, carbon monoxide, and the like in addition to carbon dioxide, which is a byproduct of the reaction formula (1). Yes.
CH ₃ OCH ₃ + 3H ₂ O → 6H ₂ + 2CO ₂ (1)
2CH ₄ + O ₂ → CH ₃ OCH ₃ + H ₂ O (2)
CH ₄ + 1 / 2O ₂ → CO + 2H ₂ (3)

The first purification unit 20 includes a plurality of first adsorption towers 21 (21A, 21B, 21C), a first on-off valve 22 (22A, 22B, 22C), and a first heat medium on-off valve 23 ( 23A, 23B, 23C), the heat medium exhaust valve 24 (24A, 24B, 24C), and the gas purge valve 25 (25A, 25B, 25C) for opening and closing the gas flow from any one of the air purge unit 14 and the hydrogen purge unit 15. ).
The first purification unit 20 configured in this manner removes a substance having a large molecular weight such as DME from impurities contained in the hydrogen mixed gas. Further, by the opening and closing operations of the various valves described above, the three steps of the DME adsorption process, the oxidative decomposition process, and the cooling process are sequentially performed in the plurality of first adsorption towers 21 (21A, 21B, and 21C) arranged in parallel. To do.

As shown in FIG. 2, the first adsorption tower 21 includes a first enclosure tube 28 in which a first adsorbent 26 is enclosed, and a pair of first sealing lids 29 that seal both ends of the first enclosure tube 28. And is composed of.
The first adsorption tower 21 configured in this way is connected in parallel to each of the branched ends of the first flow path 17 (FIG. 1), and removes the hydrocarbon gas component (unreacted DME) contained in the hydrogen mixed gas. The hydrogen mixed gas is sent to the second flow path 18 (FIG. 1) after being adsorbed and removed by the first adsorbent 26.
In addition, in FIG. 1, the number of arrangement | sequences of the 1st adsorption tower 21 is an illustration, Comprising: It can arrange in two or more.

The first adsorbent 26 is, for example, pelletized activated carbon having a diameter of 3 to 5 mmΦ, but is not limited thereto, and has a function of adsorbing a hydrocarbon gas component (unreacted DME) from a passing hydrogen mixed gas. As long as it has an adsorbing component by heating and the adsorbing function is recovered, it can be appropriately employed.
If the hydrogen mixed gas is continuously supplied to the first adsorbent 26, the adsorption amount of the hydrocarbon gas component (unreacted DME) reaches a saturated state, and the adsorption function of the hydrogen mixed gas decreases.
In this case, the adsorbed hydrocarbon gas component (unreacted DME) can be desorbed or decomposed by raising the temperature of the first adsorbent 26, and further by purging the oxygen-containing gas (air) This decomposition reaction can be promoted.

The first enclosing tube 28 has a double tube structure in which cylindrical tubes are concentrically arranged, and a heat medium for heating the first adsorbent 26 is provided outside the first adsorbent 26 enclosed inside. It is structured to flow.
The first sealing lid 29 seals both ends of the first sealed tube 28 and holds the inside of the first sealed tube 28 in a sealed state. The upstream first sealing lid 29 through which the hydrogen mixed gas flows is connected to the first flow path 17 (FIG. 1) in which the first on-off valve 22 is provided, and the downstream first sealing lid. 29 is connected to the second flow path 18 (FIG. 1) that guides the hydrogen mixed gas to the second purification unit 30.

Further, a flow path connected to a gas purge valve 25 that opens and closes the flow of the oxygen-containing gas (air) supplied from the air purge section 14 (FIG. 1) is connected to the first sealing lid 29 on the downstream side.
Then, the gas purge valve 25 is opened as the first heat medium opening / closing valve 23 is opened to start the heat treatment, and oxygen-containing gas (air) is introduced into the first enclosure tube 28.
This air passes through the first adsorbent 26 and supplies oxygen necessary for oxidizing and decomposing the adsorbed hydrocarbon gas component (unreacted DME). This decomposition gas is the first sealing on the upstream side. The air is exhausted from the exhaust hole 27 connected to the lid 29.

The first on-off valve 22 (22A, 22B, 22C) shown in FIG. 1 is a normally closed valve, and by opening any one of them, the hydrogen mixed gas output from the hydrogen generating unit 11 is the first. The flow is caused to flow in any direction in which the flow path 17 branches.
More specifically, the first on-off valve 22A is opened, the first on-off valves 22B and 22C are closed, and the hydrogen mixed gas flows only in the first adsorption tower 21A. When the adsorption capacity of the first adsorption tower 21A reaches saturation, the first on-off valve 22B is opened, the first on-off valves 22A and 22C are closed, and the hydrogen mixed gas is supplied only to the first adsorption tower 21B. Let it flow. Furthermore, this is repeated in order.
In addition, as a method of determining whether or not the adsorption capacity of the first adsorption tower 21 has reached saturation, the hydrogen mixed gas flowing through the second flow path 18 is separated and the remaining hydrocarbon gas components (unreacted) There are also a method for inspecting the concentration of DME) and a method for judging from the amount of hydrogen mixed gas that has passed through the first adsorption tower 21.

The first heat medium opening / closing valve 23 (23A, 23B, 23C) is a normally closed valve, and after the first opening / closing valve 22 is changed from the open state to the closed state, the direction in which the hydrogen mixed gas flows is switched. The first heat medium opening / closing valve 23 corresponding to the first adsorption tower 21 in which the flow of the hydrogen mixed gas has stopped switches to an open state and supplies the heat medium.
That is, the first heat medium opening / closing valve 23 oxidizes the DME adsorbed on the first adsorbent 26 (FIG. 2) through the first adsorption tower 21 in which the hydrogen mixed gas flows and the adsorption capacity is saturated. Decompose. Here, the heat medium source 13 located at the most upstream of the flow path provided with the first heat medium opening / closing valve 23 supplies a heat medium at a temperature at which DME adsorbed on the first adsorbent 26 (activated carbon) is oxidatively decomposed. For example, industrial exhaust heat or generated heat of a nuclear power plant can be used.

The heat medium exhaust valve 24 (24A, 24B, 24C) opens and closes in synchronization with the corresponding first heat medium open / close valve 23 (23A, 23B, 23C), and passes through the first adsorption tower 21. The heat medium after having been discharged is discharged.
Since the heat medium discharged from the heat medium exhaust valve 24 is heated by the oxidation heat of activated carbon, the heat can be reused in the hydrogen generator 11 or the second adsorption tower 31 (not shown).

The gas purge valve 25 (25A, 25B, 25C) opens and closes the gas flow from either the air purge unit 14 or the hydrogen purge unit 15.
That is, the first adsorbing tower in which the flow of the hydrogen mixed gas is stopped in synchronization with the flow of the hydrogen mixed gas toward another first adsorption tower 21 is switched between the open / closed state of the first on-off valve 22. The gas purge valve 25 corresponding to 21 is switched from the closed state to the open state.

Here, when the gas purge valve 25 is opened, the exhaust hole 27 (FIG. 2) provided with a check valve (not shown) serves as a purge gas escape path.
When the purge gas escape path is thus formed, the shutoff valve 14A of the air purge section 14 is opened, and the oxygen-containing gas (air) is purged into the first adsorption tower 21 in which the gas purge valve 25 is opened.
By this air purge, the oxidatively decomposed hydrocarbon gas component (unreacted DME) is released from the first adsorbent 26 and discharged to the outside of the first adsorption tower 21.

After the function of the first adsorbent 26 is restored by such processing, the corresponding first heat medium opening / closing valve 23 is returned to the closed state, the supply of the heat medium is stopped, and the temperature of the first adsorption tower 21 is further increased. Cool down.
The cooling of the first adsorption tower 21 is performed by returning the shutoff valve 14A of the air purge section 14 to the closed state and opening the shutoff valve 15A of the hydrogen purge section 15 to purge the first adsorbent 26.
Then, when the first adsorption tower 21 is sufficiently cooled and the inside thereof is sufficiently replaced with hydrogen, the gas purge valve 25 returns to the closed state, and the first adsorption tower 21 performs the next DME adsorption step (first step). The on-off valve 22 is in a waiting state until the order in which the on-off valve 22 is in the open state is circulated.

As shown in FIG. 1, the second purification unit 30 includes a plurality of second adsorption towers 31 (31A, 31B, 31C) arranged in parallel, a second on-off valve 32 (32A, 32B, 32C), 2 Heat medium open / close valve 33 (33A, 33B, 33C), heat medium exhaust passage 37 (FIG. 3), and hydrogen purge valve 35 (35A, 35B, 35) for opening and closing the flow of hydrogen gas supplied from the hydrogen purge unit 15 35C) and a pressure reducing valve 36 (36A, 36B, 36C) for opening and closing the pressure reducing force by the suction part 16.
The second refining unit 30 configured as described above has an inorganic gas component such as carbon dioxide and carbon monoxide contained in the hydrogen mixed gas after removal of a substance having a large molecular weight such as DME, methane gas, and other low molecular weights. Remove gas impurities.
Further, by the opening and closing operations of the various valves described above, the three steps of the adsorption step, the impurity removal step, and the cooling step are sequentially executed in the plurality of second adsorption towers 31 (31A, 31B, 31C) arranged in parallel. Is.

As shown in FIG. 3, the second adsorption tower 31 includes a second enclosure tube 38 in which a second adsorbent 34 (34 </ b> A, 34 </ b> B, 34 </ b> C) is enclosed, and a pair for sealing both ends of the second enclosure tube 38. And a second sealing lid 39.
The second adsorption tower 31 configured as described above is connected in parallel to each of the branched ends of the second flow path 18 (FIG. 1), and includes an inorganic gas component contained in the hydrogen mixed gas and other low molecular gas components ( Carbon dioxide, carbon monoxide, methane) is adsorbed and removed by the second adsorbent 34, and then this hydrogen mixed gas is sent to the hydrogen accumulation unit 12.
In addition, in FIG. 1, the number of arrangement | sequences of the 2nd adsorption tower 31 is an illustration, Comprising: It can arrange suitably in two or more.

The second adsorbent 34 (34A, 34B, 34C) is, for example, pellets of 1.5 mmΦ, and is composed of a plurality of layers (three layers in the figure) having different pore diameters.
And each layer which comprises the 2nd adsorption agent 34 is filled so that this hole diameter may become small toward the downstream from the upstream where hydrogen mixed gas flows.
As a result, impurities having a higher molecular weight are removed in order.

The material of the second adsorbent 34 is not limited to zeolite, and has a function of adsorbing inorganic gas components and other low-molecular gas components from the passing hydrogen mixed gas, and the adsorbing components are released by heating. As long as the adsorption function can be recovered, it can be adopted as appropriate.
If the hydrogen mixed gas is continuously supplied to the second adsorbent 34, the adsorption amount of the inorganic gas component and other low molecular gas components reaches a saturated state, and the adsorption function of the hydrogen mixed gas decreases.
In this case, by increasing the temperature of the second adsorbent 34, the adsorbed inorganic gas component and other low molecular gas components can be released, and further, the release is promoted by reducing the atmosphere. Can do.

The second enclosing tube 38 causes the heat medium to flow outside the second adsorbent 34 enclosed inside.
The upstream second sealing lid 39 through which the hydrogen mixed gas flows is connected to the flow path in which the second on-off valve 32 is provided, and the downstream second sealing lid 39 includes a hydrogen accumulation unit. 12 is connected to a flow path for introducing a hydrogen mixed gas.
Further, the second sealing lid 39 on the upstream side is connected to the suction part 16 (FIG. 1) that depressurizes the inside of the second sealing tube 38 in accordance with the opening of the second heat medium opening / closing valve 33. Yes.

Then, as the second heat medium opening / closing valve 33 is opened and the heat treatment is started, the pressure reducing valve 36 is opened, and the second adsorbent 34 inside the second sealed tube 38 is brought into a high temperature / pressure reduced atmosphere. It is configured to expose.
As described above, when the second adsorbent 34 is exposed to a high temperature / depressurized atmosphere, the adsorbed inorganic gas components and other low molecular gas components are separated and discharged in the direction of the suction unit 16.
Furthermore, a flow path connected to the hydrogen purge valve 35 that opens and closes the flow of the hydrogen gas supplied from the hydrogen purge unit 15 is connected to the second sealing lid 39 on the downstream side to release inorganic gas components and the like. The second adsorbent 34 is purged with hydrogen.
Here, the structures of the second sealing tube 38 and the second sealing lid 39 correspond to the structures of the first sealing tube 28 and the first sealing lid 29 in FIG. Detailed description is omitted.

The second on-off valve 32 (32A, 32B, 32C) shown in FIG. 1 is a normally closed valve, and by opening any one of them, the hydrogen mixed gas output from the first adsorption tower 21 is changed to the first. The two flow paths 18 are caused to flow in any branched direction.
More specifically, the second on-off valve 32A is opened, the second on-off valves 32B and 32C are closed, and the hydrogen mixed gas flows only in the second adsorption tower 31A. When the adsorption capacity of the second adsorption tower 31A reaches saturation, the second on-off valve 32B is opened, the second on-off valves 32A, 32C are closed, and the hydrogen mixed gas is supplied only to the second adsorption tower 31B. Let it flow. Furthermore, this is repeated in order.
In addition, as a method for determining whether or not the adsorption capacity of the second adsorption tower 31 has reached saturation, the hydrogen gas directed to the hydrogen accumulation unit 12 is fractionated, and the remaining inorganic gas components and other low molecular gases are collected. There are also a method of inspecting the concentration of the component and a method of judging from the amount of the hydrogen mixed gas that has passed through the second adsorption tower 31.

The second heat medium opening / closing valve 33 (33A, 33B, 33C) is a normally closed valve, and after the second opening / closing valve 32 is changed from the open state to the closed state, the direction in which the hydrogen mixed gas flows is switched. The second heat medium opening / closing valve 33 corresponding to the second adsorption tower 31 in which the flow of the hydrogen mixed gas has stopped switches to the open state and supplies the heat medium.
That is, the second heat medium opening / closing valve 33 allows the heat medium to pass through the second adsorption tower 31 in which the hydrogen mixed gas flows and the adsorption capacity is saturated, and removes the inorganic gas components adsorbed on the second adsorbent 34 and the like. Let
Here, the heat medium source 13 located at the uppermost stream of the flow path provided with the second heat medium opening / closing valve 33 is a temperature (200 ° C.) for releasing the inorganic gas component adsorbed on the second adsorbent 34 (zeolite). The heat medium can be used as long as it can supply, for example, industrial exhaust heat or generated heat of a nuclear power plant.
Alternatively, the exhaust gas from the heat medium exhaust valve 24 when the function of the first adsorption tower 21 is recovered can be used.

  The heat medium exhaust passage 37 (FIG. 3) is introduced from the corresponding second heat medium opening / closing valve 33 and discharges the heat medium after passing through the second enclosure tube 38.

The pressure reducing valve 36 (36A, 36B, 36C) opens and closes the pressure reducing force from the suction unit 16 (FIG. 1).
In other words, the first adsorbing tower in which the flow of the hydrogen mixed gas is stopped in synchronization with the flow of the hydrogen mixed gas toward another second adsorption tower 31 is switched between the open / closed state of the second on-off valve 32. The pressure reducing valve 36 corresponding to 21 is switched from the closed state to the open state.

Further, in synchronization with the pressure reducing valve 36 being opened, the corresponding second heat medium opening / closing valve 33 is opened and the heat medium is supplied to the second adsorption tower 31.
In this way, when the second adsorbent 34 is placed at a high temperature and under reduced pressure, the adsorbed inorganic gas components and the like (such as carbon dioxide) are separated and discharged to the outside of the second adsorption tower 31. .
At this time, suction by the suction unit 16 is performed from the upstream side of the second adsorption tower 31 so that the separated inorganic gas component having a large molecular weight or the like does not block the pore diameter of the second adsorbent 34 (FIG. 3). To.

The hydrogen purge valve 35 (35A, 35B, 35C) opens and closes the flow of hydrogen gas supplied from the hydrogen purge unit 15.
That is, after the adsorption function has been restored to the second adsorbent 34 under high temperature and reduced pressure, the corresponding second heat medium opening / closing valve 33 is returned to the closed state, supply of the heat medium is stopped, and the temperature rises due to heating. The second adsorption tower 31 is cooled.

The cooling of the second adsorption tower 31 is performed by returning the pressure reducing valve 36 to the closed state, opening the shutoff valve 15B of the hydrogen purge unit 15 and the hydrogen purge valve 35, and supplying hydrogen to the second adsorbent 34. . In addition, after the internal pressure of the second adsorption tower 31 has recovered to normal pressure, the purging of hydrogen gas may be further continued.
At this time, a hydrogen gas purge is performed from the downstream side of the second adsorption tower 31 so that the inorganic gas component having a large molecular weight remaining in the second adsorbent 34 does not block the pore diameter of the second adsorbent 34. Like that.
Then, when the second adsorption tower 21 is sufficiently cooled and the inside thereof is sufficiently replaced with hydrogen, the hydrogen purge valve 35 returns to the closed state, and the second adsorption tower 31 is used in the next adsorption step (second It will be in a waiting state until the order of the on-off valve 32 is opened).

The hydrogen production method according to this embodiment will be described based on the flowchart of FIG. 4 (see FIG. 1 as appropriate).
First, a hydrogen mixed gas is output from the hydrogen generation unit 11 using a hydrocarbon compound (DME) as a raw material (S11). Then, the hydrogen mixed gas is caused to flow into one of the first adsorption towers 21 connected in parallel to the branched tip of the first flow path 17 (S12; first flow step).

Thereby, when hydrogen mixed gas passes the 1st adsorption tower 21, the hydrocarbon gas component contained is adsorbed and removed (S13No; 1st adsorption step).
Then, the hydrogen mixed gas after passing through the first adsorption tower 21 flows through one of the second adsorption towers 31 connected in parallel to the branched tip of the second flow path 18 (S16; second flow step). .

On the other hand, when the adsorption of the hydrocarbon gas component in the first adsorption tower 21 reaches a saturated state (S13 Yes), the flow direction of the hydrogen mixed gas is switched to cause another first adsorption tower 21 to flow (S14). ), The second adsorption tower 31 is flowed (S16; second flow step).
In parallel with this, the heat medium is passed through the original first adsorption tower 21 where the flow of the hydrogen mixed gas is stopped to recover the adsorption function (S15; heat medium flow step).

After being output from the first adsorption tower 21, when the hydrogen mixed gas passes through the second adsorption tower 31, the contained inorganic gas component is adsorbed and removed (S17 No; second adsorption step).
Then, the hydrogen mixed gas after passing through the second adsorption tower 31 is accumulated in the hydrogen accumulation unit 12 (S20).

On the other hand, when the adsorption of the inorganic gas component in the second adsorption tower 31 reaches a saturated state (S17 Yes), the flow direction of the hydrogen mixed gas is switched to cause another second adsorption tower 31 to flow (S18). The hydrogen is accumulated in the hydrogen accumulation unit 12 (S20).
In parallel with this, the heat medium is passed through the original second adsorption tower 31 where the flow of the hydrogen mixed gas is stopped to recover the adsorption function (S19; heat medium flow step).
The routine from S11 to S20 is continued until the generation of the hydrogen mixed gas in the hydrogen generator 11 is stopped (S21).

Next, examples in which the effects of the present invention have been confirmed will be described.
A simulated gas having a composition of 73% hydrogen, 5% DME, 23% carbon dioxide, 50 ppm methane, and 50 ppm carbon monoxide was produced as the hydrogen mixed gas generated in the hydrogen generating unit 11.
A container (activated carbon tower) in which 30 g of pelletized activated carbon having a diameter of 3 to 5 mmΦ was enclosed as an equivalent to the first adsorption tower 21 was produced.
Corresponding to the second adsorption tower 31, three types of 1.5 mmΦ pellets made by Tosoh Corporation, 18 g of Zeolum HA, 9 g of Zeolum 500A, and 65 g of Zeorum 600A were filled in order from the top. (Zeolite tower) was produced ("Zeoram" is a registered trademark).

The activated carbon tower and the zeolite tower were connected in series, the simulated gas was supplied from the activated carbon tower side at 60 ml / min for 30 minutes, and the gas output from the zeolite tower side was collected.
The gas concentration of the collected gas was 99.99% or more for hydrogen concentration and 1 ppm or less for other components.

Next, as a recovery process of the adsorption function, the activated carbon tower was heated at 200 ° C., and the zeolite tower was heated at 200 ° C. under a reduced pressure of 0.07 MPa. Then, it cooled, hydrogen was supplied at 50 ml / min, and the inside of the activated carbon tower and the zeolite tower was substituted with hydrogen gas.
After performing such heat treatment, a simulated gas was supplied from the side of the activated carbon tower at 60 ml / min for 30 minutes under the same conditions as before, and the gas output from the side of the zeolite tower was collected.
The gas concentration of the collected gas was 99.99% or more of the same hydrogen concentration as the result before the heat treatment, and 1 ppm or less for other components.
As a result, it is proved that an activated carbon tower and a zeolite tower are provided in series, and a high-efficiency hydrogen production apparatus capable of repeatedly producing high-purity hydrogen by heat treating them to recover the adsorption function is demonstrated. It was done.

<Comparative example>
Next, as a comparative example, hydrogen purification of the simulated gas is attempted using only the zeolite tower without using the activated carbon tower.
FIG. 5 shows the time change of the DME concentration in the gas output from the zeolite tower in the comparative example. Here, immediately before the time point indicated by ▽, the adsorption capacity of the zeolite tower reaches saturation, and the heat treatment of the zeolite tower is performed at the time point indicated by 印.
In addition, the vertical axis | shaft and horizontal axis | shaft in FIG. 5 are each shown by the arbitrary scale.

According to FIG. 5, in the comparative example, the DME concentration shows a result comparable to that of the example from the start of the test until the adsorption capacity reaches saturation. However, once the adsorption capacity is saturated, the adsorption function of the zeolite tower has not recovered even after heat treatment.
On the other hand, when the activated carbon container is connected in series with the preceding stage of the zeolite container as in the example, it has been confirmed that the same DME concentration trajectory is repeated by the heat treatment as in FIG.

The present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented within the scope of the common technical idea.
For example, the arrangement of the valves that regulate the gas flow in the hydrogen production apparatus is not limited to that shown in the embodiment, and may be appropriately adopted as long as a desired gas flow is realized. Further, the switching of the gas flow is not limited to that based on such valve opening / closing operation.

Known types of valves for switching the gas flow and their opening / closing operations are applied. In addition, the case where the operating subject of the valve control is a computer and executes a valve opening / closing operation designated based on a program is also included.
In addition, although description is abbreviate | omitted, in each flow path, the check valve for preventing a backflow is provided suitably.

  DESCRIPTION OF SYMBOLS 10 ... Hydrogen production apparatus, 11 ... Hydrogen generation part, 12 ... Hydrogen storage part, 13 ... Heat-medium source, 14 ... Air purge part, 14A ... Shut-off valve, 15 ... Hydrogen purge part, 15A ... Shut-off valve, 15B ... Shut-off valve, 16 ... suction section, 17 ... first flow path, 18 ... second flow path, 20 ... first purification section, 21 (21A, 21B, 21C) ... first adsorption tower, 22 (22A, 22B, 22C) ... first 1 on-off valve, 23 (23A, 23B, 23C) ... first heat medium on-off valve (heat medium on-off valve), 24 ... heat medium exhaust valve, 25 ... gas purge valve, 26 ... first adsorbent, 27 ... exhaust hole, 28 ... 1st enclosure tube, 29 ... 1st sealing lid, 30 ... 2nd refinement | purification part, 31 (31A, 31B, 31C) ... 2nd adsorption tower, 32 (32A, 32B, 32C) ... 2nd on-off valve, 33 (33A, 33B, 33C) ... second heat medium on / off valve (heat medium on / off valve), 34 (34A, 34B) 34C) ... second adsorbent, 35 ... hydrogen purge valve, 36 ... pressure reducing valve, 37 ... heat medium exhaust passage, 38 ... second fill pipe, 39 ... second sealing lid.

Claims (10)

A first on-off valve for flowing a hydrogen mixed gas output from a hydrogen generation unit using a hydrocarbon-based compound as a raw material in any direction branched from the first flow path;
A plurality of first adsorption towers connected in parallel to each of the branches of the first flow path to adsorb hydrocarbon gas components contained in the hydrogen mixed gas;
A second on-off valve that causes the hydrogen mixed gas output from the first adsorption tower to flow in any direction branched from the second flow path;
A plurality of second adsorption towers connected in parallel to each of the branches of the second flow path and adsorbing inorganic gas components contained in the hydrogen mixed gas;
A heating medium opening / closing valve for allowing a heating medium to pass through the first adsorption tower or the second adsorption tower in which the flow of the hydrogen mixed gas is stopped by switching the flow direction of the first opening / closing valve or the second opening / closing valve; A hydrogen production apparatus comprising: The first adsorption tower is
A first enclosing tube for allowing the heat medium to flow outside the first adsorbent encapsulated inside;
2. The hydrogen production according to claim 1, further comprising: a first sealing lid connected to a gas purge valve that purges oxygen-containing gas inside the first sealed pipe in accordance with opening the heat medium opening / closing valve. apparatus. The second adsorption tower is
A second enclosing tube for allowing the heat medium to flow outside the second adsorbent encapsulated inside;
3. The hydrogen production according to claim 1, further comprising: a second sealing lid connected to a suction unit that depressurizes the inside of the second enclosure tube in accordance with opening the heat medium opening / closing valve. apparatus. The first adsorption tower or the second adsorption tower is
A purge valve for purging the hydrogen gas to the first adsorption tower or the second adsorption tower in which the flow of the hydrogen mixed gas has stopped due to the first on-off valve or the second on-off valve switching the flow direction. The hydrogen production apparatus according to any one of claims 1 to 3.   The heat generation generated in the first adsorption tower when the heat medium on-off valve is opened and the heat medium is allowed to pass is reused in the hydrogen generation section or the second adsorption tower. The hydrogen production apparatus according to claim 1.   The hydrogen production apparatus according to any one of claims 2 to 5, wherein the first adsorbent is activated carbon.   The hydrogen production apparatus according to any one of claims 3 to 5, wherein the second adsorbent is zeolite.   8. The hydrogen production apparatus according to claim 7, wherein the second adsorbent is composed of a plurality of zeolite layers having different pore diameters, and is filled so that the pore diameter decreases from upstream to downstream where the hydrogen mixed gas flows. . A first flow step for flowing a hydrogen mixed gas output from a hydrogen generation section using a hydrocarbon-based compound as a raw material in any direction branched from the first flow path;
A first adsorption step of adsorbing a hydrocarbon gas component contained by passing the hydrogen mixed gas through any of a plurality of first adsorption towers connected in parallel to each of the branches of the first flow path;
A second flow step of flowing the hydrogen mixed gas after passing through the first adsorption tower in any direction branched from the second flow path;
A second adsorption step of adsorbing the inorganic gas component contained by passing the hydrogen mixed gas through any of a plurality of second adsorption towers connected in parallel to each of the branches of the second flow path;
A heat medium flow step for passing a heat medium through the first adsorption tower or the second adsorption tower in which the flow of the hydrogen mixed gas is stopped by switching the flow direction in the first flow step or the second flow step; The hydrogen production method characterized by including these. Computer
A first flow means for flowing a hydrogen mixed gas output from a hydrogen generation section using a hydrocarbon-based compound as a raw material in any direction branched from the first flow path;
A first adsorbing means for adsorbing a hydrocarbon gas component contained by passing the hydrogen mixed gas through any one of a plurality of first adsorbing towers connected in parallel to each of the branches of the first flow path;
Second flow means for flowing the hydrogen mixed gas after passing through the first adsorption tower in any direction branched from the second flow path;
A second adsorbing means for adsorbing the inorganic gas component contained by allowing the hydrogen mixed gas to pass through any of a plurality of second adsorption towers connected in parallel to each of the branches of the second flow path;
A heat medium flow means for passing a heat medium through the first adsorption tower or the second adsorption tower in which the flow of the hydrogen mixed gas is stopped by switching the flow direction in the first flow means or the second flow means; Hydrogen production program characterized by functioning as

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