JP2018083729A - Hydrogen manufacturing apparatus, hydrogen manufacturing system including the same, and hydrogen manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain gas with improved purity of hydrogen by a simple configuration in a hydrogen manufacturing apparatus.SOLUTION: A hydrogen manufacturing apparatus includes a first flow channel 11 that permits passage of hydrogen generated by decomposition reaction of supplied water, and a second flow channel that permits passage of oxygen generated in the first flow channel 11. At least a part of a barrier that separates the first flow channel 11 from the second flow channel 12(13) has oxygen permeability which selectively allows oxygen generated in the first flow channel 11 to permeate through the second flow channel 12(13).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hydrogen production apparatus that produces hydrogen by splitting water, a hydrogen production system including the same, and a hydrogen production method.

  Conventionally, as a technique for producing hydrogen to be supplied to a fuel cell or the like, for example, by heating a raw material gas in which water vapor is mixed with hydrocarbon or alcohol with a combustion gas, a reforming reaction is advanced by a catalyst, There is known a steam reforming method for obtaining a gas containing as a main component (see Patent Documents 1-4).

  Further, in such hydrogen production, a synthesis gas composed of hydrogen and carbon monoxide is generated by the steam reforming reaction, and further, the carbon monoxide in the synthesis gas is reduced by a shift reaction at a lower temperature. As well as being converted to carbon dioxide, hydrogen enrichment is performed.

JP-A-8-108065 JP-A-11-111321 JP 2001-192201 A JP 2002-249302 A

  By the way, according to the prior art as described in Patent Documents 1 to 4, it is possible to obtain a gas mainly composed of hydrogen. Examples of the obtained gas include carbon monoxide and carbon dioxide. And other components are contained in a relatively large amount. On the other hand, in fuel cells and the like, the use of such a low-purity gas may adversely affect the apparatus, so a gas containing higher-purity hydrogen (for example, 95 to 99.9999 vol%) may be used. desirable.

  However, when trying to obtain a gas containing hydrogen of higher purity, for example, a decarbonation step of separating carbon dioxide produced by the shift reaction by a chemical absorption method and the remaining in the decarboxylated gas. It is necessary to appropriately implement a methanation reaction step for removing trace amounts of carbon monoxide and carbon dioxide, a PSA (Pressure Swing Adsorption) step, a membrane separation step for selectively separating hydrogen, and the like. . In this case, there is a problem that the hydrogen production process becomes complicated and the production equipment is enlarged.

  The present invention has been devised in view of such problems of the prior art, and a hydrogen production apparatus capable of obtaining a gas with improved hydrogen purity and a hydrogen production equipped with the same with a simple configuration The main object is to provide a system and a hydrogen production method.

  The first aspect of the present invention relates to a hydrogen production apparatus, a first flow path through which hydrogen generated by a decomposition reaction of supplied water flows, and adjacent to the first flow path, in the first flow path A second channel through which the generated oxygen flows, and at least a part of a partition partitioning the first channel and the second channel has the oxygen generated in the first channel as the second channel. It has oxygen permeability that allows it to selectively permeate through the flow path.

  In the first aspect of the present invention, the purity of hydrogen in the first flow path is achieved by a simple configuration in which oxygen generated in the first flow path is selectively permeated to the second flow path through an oxygen permeable partition. It becomes possible to acquire the gas which improved. In addition, although unreacted water may exist in the 1st flow path with hydrogen, even in that case, the gas which improved the purity of hydrogen can be easily acquired only by removing the water.

  In the second aspect of the present invention, fuel gas further flows through the second flow path, and the fuel gas is burned by the oxygen in the second flow path.

  In the second aspect of the present invention, oxygen permeated from the first flow path to the second flow path is used for combustion of the fuel gas, so that the difference in oxygen partial pressure in the first flow path and the second flow path causes the first Good permeability of oxygen from the first flow path to the second flow path is realized.

  The third aspect of the present invention is characterized in that the combustion heat of the fuel gas is conducted to the first flow path through the partition wall that separates the first flow path and the second flow path.

  In the third aspect of the present invention, since the combustion heat of the fuel gas in the second flow path can be used for the water decomposition reaction in the first flow path, the supply of heat from the outside for the water decomposition reaction The amount can be reduced.

  In the fourth aspect of the present invention, the fuel gas contains carbon monoxide and hydrogen.

  In the fourth aspect of the present invention, the combustion heat of carbon monoxide and hydrogen in the second channel can be used for the water decomposition reaction in the first channel.

  The fifth aspect of the present invention is characterized in that oxygen or an oxygen-containing gas introduced from the outside further flows through the second flow path.

  In the fifth aspect of the present invention, it is possible to increase the amount of combustion heat of the fuel gas in the second flow path, thereby eliminating the need for external heat supply (or further reducing the amount of heat supply). Is possible.

  The sixth aspect of the present invention is characterized in that a water splitting reaction catalyst is supported on the partition wall separating the first flow path and the second flow path.

  In the sixth aspect of the present invention, the water decomposition reaction in the first flow path can be further promoted.

  In the seventh aspect of the present invention, the first flow path is defined by two flat walls arranged at a predetermined interval, and the partition is constituted by one of the two flat walls. It is characterized by being.

  In the seventh aspect of the present invention, it is possible to obtain a gas with improved hydrogen purity in the first flow path by a simple flow path configuration using a flat wall.

  In the eighth aspect of the present invention, the other of the two flat walls further constitutes the partition wall, and the second flow path passes through the two flat walls, respectively. Including two flow paths adjacent to each other.

  In the eighth aspect of the present invention, the area of the partition wall that allows oxygen to permeate from the first flow path to the second flow path (that is, the oxygen permeation region) can be secured larger, and a desired oxygen permeation amount can be obtained. It becomes possible to maintain stably.

  In a ninth aspect of the present invention, the apparatus further comprises a third flow channel adjacent to the second flow channel and through which an oxygen-containing gas introduced from the outside flows, and the second flow channel and the third flow channel are provided. At least a part of the partition walls is characterized by having oxygen permeability that selectively allows oxygen contained in the oxygen-containing gas in the third flow path to pass through the second flow path.

  In the ninth aspect of the present invention, since the amount of combustion gas (that is, the amount of combustion heat) can be increased by increasing the amount of oxygen flowing through the second flow path, it is not necessary to supply heat from the outside ( Alternatively, the amount of heat supply can be further reduced).

  In the tenth aspect of the present invention, the partition that separates the second flow path and the third flow path is spaced apart from the partition that separates the first flow path and the second flow path. It consists of a further flat plate-like wall arranged.

  In the tenth aspect of the present invention, it is possible to obtain a gas with improved hydrogen purity in the first flow path by a simple flow path configuration using a flat wall.

  In an eleventh aspect of the present invention, an inert gas for purging the oxygen flows through the second flow path.

  In the eleventh aspect of the present invention, oxygen permeated from the first flow path to the second flow path is purged by the inert gas, so that the difference in oxygen partial pressure in the first flow path and the second flow path causes the first Good permeability of oxygen from the first flow path to the second flow path is realized.

  In a twelfth aspect of the present invention, the second flow path is decompressed.

  In the twelfth aspect of the present invention, since the oxygen permeated from the first flow path to the second flow path is reduced by the decompression of the second flow path, the difference in oxygen partial pressure between the first flow path and the second flow path A good oxygen permeability from the first channel to the second channel is realized.

  A thirteenth aspect of the present invention relates to a hydrogen production system, comprising: the hydrogen production apparatus according to any one of the first to fourteenth aspects; and a hydrogen utilization apparatus to which hydrogen produced by the hydrogen production apparatus is supplied. It is characterized by providing.

  In a thirteenth aspect of the present invention, a hydrogen utilization device (for example, a fuel cell) is configured with a simple configuration that selectively transmits oxygen generated in the first flow path to the second flow path through the oxygen permeable partition wall. ), It is possible to supply a gas with improved hydrogen purity in the first flow path.

  In the fourteenth aspect of the present invention, the step of circulating hydrogen generated by the decomposition reaction of the supplied water to the first channel and the second channel adjacent to the first channel by the decomposition reaction And the step of circulating oxygen in the second flow path is generated by the decomposition reaction through a partition wall that separates the first flow path and the second flow path. And a step of selectively permeating the oxygen into the second flow path.

  In the fifteenth aspect of the present invention, the purity of hydrogen in the first flow path is achieved by a simple configuration that selectively transmits oxygen generated in the first flow path to the second flow path through the oxygen permeable partition. It becomes possible to acquire the gas which improved.

  In another aspect of the present invention, the fuel gas includes a gas generated by steam reforming of a hydrocarbon fuel.

  According to this, since the combustion heat amount of the fuel gas in the second flow path can be increased, it is possible to eliminate the need for external heat supply (or to further reduce the heat supply amount). .

  In another aspect of the present invention, the fuel gas includes a gas generated by carbon dioxide reforming of a hydrocarbon fuel.

  According to this, since the combustion heat amount of the fuel gas in the second flow path can be increased, it is possible to eliminate the need for external heat supply (or to further reduce the heat supply amount). .

  In another aspect of the present invention, the fuel gas includes a gas generated by partial oxidation of a hydrocarbon fuel.

  According to this, since the combustion heat amount of the fuel gas in the second flow path can be increased, it is possible to eliminate the need for external heat supply (or to further reduce the heat supply amount). .

  Thus, according to the present invention, it is possible to obtain a gas with improved hydrogen purity with a simple configuration.

Configuration diagram of a hydrogen production system according to the first embodiment Explanatory drawing which shows the principal part of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 1st modification of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 2nd modification of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 3rd modification of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 4th modification of the hydrogen production apparatus shown in FIG. Configuration diagram of a hydrogen production system according to the second embodiment Explanatory drawing which shows the principal part of the hydrogen production apparatus shown in FIG. Configuration diagram of a hydrogen production system according to the third embodiment Explanatory drawing which shows the principal part of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the modification of the hydrogen production apparatus shown in FIG. Configuration diagram of a hydrogen production system according to the fourth embodiment Explanatory drawing which shows the principal part of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 1st modification of the hydrogen production apparatus shown in FIG. Explanatory drawing which shows the 2nd modification of the hydrogen production apparatus shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a configuration diagram of a hydrogen production system 1 according to the first embodiment of the present invention, and FIG. 2 is an explanatory view showing a main part of the hydrogen production apparatus 2 shown in FIG. 5 and 6 are explanatory views showing first, second, third, and fourth modified examples of the hydrogen production apparatus shown in FIG. 2, respectively. In addition, the direction shown by the arrow in FIG. 2 is for convenience of explanation, and does not limit the practical direction (the same applies to other drawings). In FIG. 4 and subsequent figures, the same structure as that of the hydrogen production apparatus 2 shown in FIG. 2 is shown in a simplified manner.

  As shown in FIG. 1, a hydrogen production system 1 includes a hydrogen production apparatus 2 that produces hydrogen by water decomposition, a water supply apparatus 3 that supplies water as a raw material to the hydrogen production apparatus 2, and a hydrogen production apparatus 2. It mainly includes a hydrogen utilization device 4 that utilizes the produced hydrogen.

  Here, the water supply device 3 includes a known pump or the like, and can supply water to the hydrogen production device 2 from a storage tank (not shown) or the like. Further, the hydrogen utilization device 4 is composed of, for example, a known fuel cell using hydrogen as a fuel, but is not limited to this, and any other device can be used as long as a gas containing hydrogen as a main component can be used. It is possible to use.

As shown in FIG. 2, the hydrogen production apparatus 2 includes a first flow path 11 through which water and hydrogen (H ₂ ) generated by the decomposition reaction of water flow, and the first flow path 11 is adjacent to the first flow path 11. And second flow paths 12 and 13 through which oxygen (O ₂ ) generated in the flow path flows. Although not shown, the left and right directions of the first flow path 11 and the second flow paths 12 and 13 are substantially non-gas permeable walls (for example, made of metal) Member).

  The first flow path 11 is defined by two upper and lower flat walls (partition walls) 14 and 15 arranged in parallel with each other at a predetermined interval. The walls 14 and 15 have oxygen permeability that allows oxygen to permeate selectively. For example, the walls 14 and 15 can be formed of a known oxygen-permeable ceramic film.

  For details of such ceramic membranes, see, for example, Wenping Li, Xuefeng Zhu, Zhongwei Cao, Weiping Wang, Weishen Yang. "Mixed ionic-electronic conducting (MIEC) membranes for hydrogen production from water splitting." International Journal of Hydrogen Energy. , Volume 40, Issue 8, 2 March 2015, Pages 3452-3461, CY Park, TH Lee, SE Dorris, U. Balachandran. "Hydrogen production from fossil and renewable sources using an oxygen transport membrane." International Journal of Hydrogen Energy. International Journal of Hydrogen Energy, Volume 35, Issue 9, May 2010, Pages 4103-4110, U. (Balu) Balachandran, TH Lee, SE Dorris. "Hydrogen production by water dissociation using mixed conducting dense ceramic membranes." International Journal of See Hydrogen Energy, Volume 32, Issue 4, March 2007, Pages 451-456, etc.

  The oxygen-permeable wall that defines the flow path of the hydrogen production apparatus 2 may be any wall that can be used at least in an environment such as the temperature and pressure at which the hydrogen production apparatus 2 operates. Not limited to this, other known oxygen-permeable members (members that substantially allow only oxygen to permeate) can be used.

  The second flow paths 12 and 13 have the same structure as each other, and one of the two flat walls 14 and 15 that delimit the first flow path 11 and the walls 16 and 17 that face each other. Respectively. The walls 16 and 17 do not have gas permeability and are arranged in parallel to each other with a predetermined distance from the walls 14 and 15.

In the hydrogen production process, in the first channel 11, water (here, steam) flows from the upstream side (rear side in FIG. 2), and this water is decomposed (H ₂ O → H ₂ + 0.5O _2). ) To generate hydrogen and oxygen. The oxygen thus generated passes through the walls 14 and 15 (here, permeated as oxygen ions) and flows into the second flow paths 12 and 13 positioned above and below the first flow path 11. On the other hand, the hydrogen generated in the first flow path 11 is discharged from the downstream side (front side in FIG. 2) of the first flow path 11 without passing through the walls 14 and 15. As a result, a gas with improved hydrogen purity (preferably a high-purity hydrogen gas containing 95 to 99.9999 vol% of hydrogen) is discharged from the downstream of the first flow path 11. To the hydrogen utilization device 4 as a product. Further, oxygen flowing into the second flow paths 12 and 13 is discharged from the downstream side of the second flow paths 12 and 13. In the first flow path 11, unreacted water may be present together with hydrogen, but even in that case, the gas with improved hydrogen purity can be easily removed simply by removing the water (for example, condensing). Can be acquired.

  As described above, the hydrogen production system 1 has a simple configuration in which oxygen generated in the first flow path 11 is selectively transmitted to the second flow paths 12 and 13 through the oxygen permeable walls 14 and 15. In the first flow path 11, it is possible to obtain a gas with improved hydrogen purity. Further, in the hydrogen production system 1, it is not necessary to separately prepare an apparatus for hydrogen purification as in the prior art, and a compact system can be realized.

As for the walls 14 and 15 that define the first flow path 11, at least a part of the area is oxygen permeable as long as a desired hydrogen production amount and hydrogen purity can be achieved in the exhaust gas of the first flow path 11. (That is, the walls 14 and 15 are partly formed of an oxygen-permeable ceramic film). In addition, since the water decomposition reaction (H ₂ O → H ₂ + 0.5O ₂ ) is an endothermic reaction with a standard reaction heat ΔH = 242 kJ, the heat required for this reaction is not shown in an external device (for example, a combustion device). ) To the hydrogen production apparatus 2.

  Further, the shape and size of the first flow path 11 and the second flow paths 12 and 13 and the walls that define them can be appropriately changed. In the present embodiment, as shown in FIG. 2, the second flow paths 12 and 13 are arranged so as to sandwich the upper and lower sides of the first flow path 11. However, for example, one second flow path 13 is omitted. Configuration is also possible. In that case, the wall 15 that defines the lower surface of the first flow path 11 is formed of a member that does not have gas permeability, like the wall 16. Furthermore, although the gas flow directions in the first flow path 11 and the second flow paths 12 and 13 are the same here, it is also possible to adopt a configuration in which the gases in the respective flow paths flow in directions crossing each other.

  Further, the hydrogen production apparatus 2 may have a configuration in which a plurality of first flow paths 11 are provided. In that case, for example, the structure shown in FIG. 2 can be used as a basic unit, and a plurality of these can be stacked in the vertical direction. Alternatively, the hydrogen production apparatus 2 may have a configuration in which the first channel 11 and the second channel 12 are alternately arranged in the vertical direction in the configuration in which the second channel 13 is omitted. In that case, since the two walls that define the second flow path 12 are both partition walls for the first flow path, they are each formed of a member having oxygen permeability, like the walls 14 and 15. Become.

  As a first modification of the first embodiment, for example, as shown in FIG. 3, the first flow path 11 and the second flow path 12 are a plurality of tubes (here, circular tubes) 21 arranged substantially concentrically. , 22 may be configured. In this case, the smaller diameter tube 21 is formed of a member having oxygen permeability like the above-described walls 14 and 15, and the inner peripheral surface thereof defines the first flow path 11. The larger-diameter pipe 22 is configured by a member that does not have gas permeability like the walls 16 and 17, and its inner peripheral surface defines the second flow path 12 together with the outer peripheral surface of the small-diameter pipe 21. .

  As a second modification of the first embodiment, for example, as shown in FIG. 4, an inert gas (in this case, argon (Ar)) for purging oxygen is circulated through the second flow paths 12 and 13. It is also possible to adopt a configuration. Thereby, the difference in oxygen partial pressure between the first flow path 11 and the second flow paths 12 and 13 is properly maintained, and the walls 14 and 15 from the first flow path 11 to the second flow paths 12 and 13 are interposed. It is possible to achieve good oxygen permeability.

  As a third modification of the first embodiment, for example, as shown in FIG. 5, a suction device 25 including a pump connected to the downstream side of the second flow paths 12 and 13 is provided. It is also possible to adopt a configuration in which the gas in the layers 12 and 13 is sucked (that is, the second flow paths 12 and 13 are decompressed). Thereby, like the said 2nd modification, the favorable permeability | transmittance of oxygen through the walls 14 and 15 from the 1st flow path 11 to the 2nd flow paths 12 and 13 is realizable.

  Further, as a fourth modification of the first embodiment, for example, as shown in FIG. 6, walls (here, walls 14 and 15) that define the first flow path 11 include noble metals, metal oxides, and the like. A known water splitting reaction catalyst 28 can be supported. Thereby, decomposition | disassembly of the water in a 1st flow path is accelerated | stimulated.

  In addition, about the said 1st and 4th modification and those structures equivalent to them, it is possible to employ | adopt suitably also in other embodiment mentioned later not only in this embodiment.

(Second Embodiment)
FIG. 7 is a configuration diagram of the hydrogen production system 1 according to the second embodiment of the present invention, and FIG. 8 is an explanatory diagram showing a main part of the hydrogen production apparatus 2 shown in FIG. In FIG. 7 and FIG. 8, the same code | symbol is attached | subjected to the component similar to the above-mentioned 1st Embodiment. Further, regarding the second embodiment, matters that are not particularly mentioned below are the same as those in the first embodiment (including modifications thereof), and detailed description thereof is omitted.

As shown in FIG. 7, in the hydrogen production system 1 according to the second embodiment, a fuel supply device 30 that supplies fuel gas (here, natural gas containing methane as a main component) to the hydrogen production device 2, and hydrogen production The second embodiment is different from the first embodiment in that a CO ₂ recovery device 31 that recovers carbon dioxide (CO ₂ ) generated in the device 2 is further provided.

As shown in FIG. 8, in the hydrogen production device 2 according to the second embodiment, natural gas mainly containing methane (CH ₄ ) flows from the fuel supply device 30 into the second flow paths 12 and 13. The methane in the second flow paths 12 and 13 is combusted by oxygen flowing through the walls 14 and 15 from the first flow path 11 and flowing into the second flow paths 12 and 13 (0.25CH ₄ + 0.5O ₂ → 0.25CO ₂ + 0.5H ₂ O). Combustion of methane in the above chemical formula using oxygen (0.5O ₂ ) generated by the above water splitting is an exothermic reaction with reaction heat ΔH = −200 kJ (298.15 K, 0.1 MPa). Conducted to the first flow path 11 via 15.

  The amount of heat (200 kJ) of combustion heat from the second flow paths 12 and 13 can make up part of the heat quantity (242 kJ) required for the water decomposition reaction in the first flow path 11, and the water decomposition reaction. Therefore, it becomes possible to reduce the amount of heat supplied from the external device.

Further, carbon dioxide contained in the combustion gas discharged from the downstream side (the front side in FIG. 8) of the second flow paths 12 and 13 is sent to a known CO ₂ recovery device 31 after being separated from water and recovered. Is done.

  Note that the fuel gas of the hydrogen production system 1 is not limited to natural gas, and fuels containing hydrocarbons and alcohols such as LPG (Liquefied Petroleum Gas), light oil, and gasoline can be used.

(Third embodiment)
FIG. 9 is a configuration diagram of the hydrogen production system 1 according to the third embodiment of the present invention, FIG. 10 is an explanatory diagram showing a main part of the hydrogen production apparatus 2 shown in FIG. 1, and FIG. It is explanatory drawing which shows the modification of the shown hydrogen production apparatus. 9 to 11, the same components as those in the first and second embodiments described above are denoted by the same reference numerals. Further, regarding the third embodiment, matters that are not particularly mentioned below are the same as those in the first or second embodiment (including modifications thereof), and detailed description thereof is omitted.

  As shown in FIG. 9, the hydrogen production system 1 according to the third embodiment is different from the second embodiment in that it further includes an air supply device 41 that supplies air (oxygen-containing gas) to the hydrogen production device 2. Is different.

  As shown in FIG. 10, in the hydrogen production apparatus 2 according to the third embodiment, the third flow path 43 adjacent to the walls 16 and 17 and through which air (Air) introduced from the air supply apparatus 41 circulates. , 44 further differs from the second embodiment.

  The third flow paths 43 and 44 have the same structure, and one of the two flat walls 16 and 17 that define the second flow paths 12 and 13 and the walls 46 and 47 that face each other. Respectively. In the present embodiment, the walls 16 and 17 are made of a member having oxygen permeability like the walls 14 and 15 in the first embodiment, and the walls 46 and 47 are the walls 16 and 17 in the first embodiment. Similarly to the above, they do not have gas permeability and are arranged in parallel to each other with a predetermined distance from the walls 16 and 17. Although illustration is omitted, the horizontal direction of the third flow paths 43 and 44 (direction perpendicular to the paper surface of FIG. 10) is the case of the first flow path 11 and the second flow paths 12 and 13 in the first embodiment. As well as being closed.

  In the third flow paths 43 and 44, air flows from the upstream side (rear side in FIG. 10), and oxygen contained in the air permeates the walls 16 and 17 (here, permeates as oxygen ions). It flows into the 2nd flow paths 12 and 13 arranged up and down, respectively.

Similarly to the case of the second embodiment, natural gas mainly containing methane (CH ₄ ) flows into the second flow paths 12 and 13, and this methane is converted into oxygen from the first flow path 11. In addition, combustion is performed by oxygen from the third flow paths 43 and 44 (0.3 CH ₄ +0.6 O ₂ → 0.3 CO ₂ +0.6 H ₂ O). The combustion of methane in the chemical formula is an exothermic reaction with reaction heat ΔH = −242 kJ, and this combustion heat is conducted to the first flow path 11 through the walls 14 and 15.

  As a result, the amount of combustion gas (that is, the amount of combustion heat) flowing into the second flow paths 12 and 13 can be increased, and the first flow rate is increased by the amount of combustion heat (242 kJ) from the second flow paths 12 and 13. It becomes possible to supplement almost all of the amount of heat (242 kJ) required for water decomposition in the passage 11. As a result, it is possible to eliminate the need to supply heat from the external device to the hydrogen production apparatus 2.

  In this way, by allowing only oxygen to flow into the second flow paths 12 and 13 from the third flow paths 43 and 44, it is possible to avoid nitrogen remaining in the combustion gas in the second flow paths 12 and 13. There is an advantage that carbon dioxide can be easily recovered. However, as an alternative to air, a configuration in which oxygen or an oxygen-containing gas is allowed to flow into the third flow paths 43 and 44 is also possible.

As a modification of the third embodiment, for example, as shown in FIG. 11, the third flow paths 43 and 44 are omitted, and oxygen (for example, natural gas (methane) is used for combustion in the second flow paths 12 and 13 (for example, In the third embodiment, it is also possible to supply oxygen or the oxygen-containing gas in the same amount as oxygen flowing through the third flow paths 43 and 44. In this case, methane in the second flow paths 12 and 13 is combusted by oxygen from the first flow path 11 in addition to oxygen mixed with natural gas (0.3 CH ₄ +0.6 O ₂ → 0.3 CO ₂ +0.6 H). ₂ O). The combustion of methane in the chemical formula is an exothermic reaction with reaction heat ΔH = −242 kJ, and it is possible to compensate for almost all of the heat amount (242 kJ) necessary for water decomposition in the first flow path 11. Thereby, the same effect as the third embodiment can be expected.

(Fourth embodiment)
FIG. 12 is a configuration diagram of the hydrogen production system 1 according to the fourth embodiment of the present invention, FIG. 13 is an explanatory diagram showing a main part of the hydrogen production apparatus 2 shown in FIG. 1, and FIGS. FIG. 14 is an explanatory diagram showing first and second modifications of the hydrogen production apparatus shown in FIG. 13, respectively. 12 to 15, the same reference numerals are given to the same components as those in the first to third embodiments described above. Further, regarding the fourth embodiment, matters that are not particularly mentioned below are the same as those in any of the first to third embodiments described above (including modifications thereof), and detailed description thereof is omitted.

  As shown in FIG. 12, in the hydrogen production system 1 according to the fourth embodiment, the air supply device 41 is omitted, and the reforming for reforming the fuel gas between the fuel supply device 30 and the hydrogen production device 2 is performed. The point which further provided the apparatus 51 differs from the case of 3rd Embodiment.

In the reformer 51, higher-caloric reforming including carbon monoxide and hydrogen is performed by steam reforming of fuel gas (here, natural gas) (0.25CH ₄ + 0.25H ₂ O → 0.25CO + 0.75H ₂ ). Gas is generated, and this reformed gas is sent to the hydrogen production apparatus 2 and flows into the second flow paths 12 and 13.

As shown in FIG. 13, in the hydrogen production apparatus 2 according to the fourth embodiment, the reformed gas containing carbon monoxide and hydrogen that has flowed into the second flow paths 12, 13 flows from the first flow path 11 to the walls 14, 13. combustion by the oxygen that flows 15 into the second flow path 12, 13 is transmitted through the _{(0.25CO + 0.75H 2 + 0.5O 2} → 0.25CO 2 + 0.75H 2 O) to. The combustion of the reformed gas in the chemical formula is an exothermic reaction with reaction heat ΔH = −252 kJ, and this combustion heat is conducted to the first flow path 11 through the walls 14 and 15.

  The amount of heat (252 kJ) of the combustion heat from the second flow paths 12 and 13 can compensate for almost all of the heat quantity (242 kJ) required for water decomposition in the first flow path 11. As a result, as in the case of the third embodiment, it is possible to eliminate the need to supply heat from an external device to the hydrogen production apparatus 2. Note that water discharged from the downstream side of the second flow paths 12 and 13 can circulate upstream of the reformer 51 and the first flow path 11.

Further, as a first modification of the reformer 51, carbon monoxide and hydrogen are produced by carbon dioxide reforming (0.25CH ₄ + 0.25CO ₂ → 0.5CO + 0.5H ₂ ) of fuel gas (here, natural gas). It is also possible to produce a higher-calorie reformed gas containing

Thereby, as shown in FIG. 14, the reformed gas that has flowed into the second flow paths 12 and 13 passes through the walls 14 and 15 from the first flow path 11 and flows into the second flow paths 12 and 13. (0.5CO + 0.5H ₂ + 0.5O ₂ → 0.5CO ₂ + 0.5H ₂ O). The combustion of the reformed gas in the chemical formula is an exothermic reaction with reaction heat ΔH = −263 kJ, and this combustion heat is conducted to the first flow path 11 through the walls 14 and 15.

  The amount of combustion heat (263 kJ) from the second flow paths 12 and 13 makes it possible to supplement substantially all of the heat quantity (242 kJ) required for water decomposition in the first flow path 11. As a result, as in the case of the third embodiment, it is possible to eliminate the need to supply heat from an external device to the hydrogen production apparatus 2.

Further, as a second modification of the reformer 51, carbon monoxide and hydrogen are contained by partial oxidation (0.25CH ₄ + 0.125O ₂ → 0.25CO + 0.5H ₂ ) of fuel gas (here, natural gas). It is also possible to adopt a configuration that generates a higher-calorie reformed gas.

As a result, as shown in FIG. 15, the reformed gas that has flowed into the second flow paths 12, 13 passes through the walls 14, 15 from the first flow path 11 and flows into the second flow paths 12, 13. (0.33CO + 0.67H ₂ + 0.5O ₂ → 0.33CO ₂ + 0.67H ₂ O). The combustion of the reformed gas in the chemical formula is an exothermic reaction with reaction heat ΔH = −256 kJ, and this combustion heat is conducted to the first flow path 11 through the walls 14 and 15.

  With the amount of heat of combustion heat (256 kJ) from the second flow paths 12 and 13, substantially all of the heat quantity (242 kJ) necessary for water decomposition in the first flow path 11 can be compensated. As a result, as in the case of the third embodiment, it is possible to eliminate the need to supply heat from an external device to the hydrogen production apparatus 2.

  As mentioned above, although this invention was demonstrated based on specific embodiment, these embodiment is an illustration to the last, Comprising: This invention is not limited by these embodiment. Note that the components of the hydrogen production apparatus according to the present invention, the hydrogen production system including the hydrogen production system, and the hydrogen production method shown in the above-described embodiments are not necessarily essential, and at least as long as they do not depart from the scope of the present invention. It is possible to make selections as appropriate.

DESCRIPTION OF SYMBOLS 1 Hydrogen production system 2 Hydrogen production apparatus 3 Water supply apparatus 4 Hydrogen utilization apparatus 11 1st flow path 12, 13 2nd flow path 14, 15 Wall 16, 17 Wall 21, 22 Pipe 25 Suction apparatus 28 Water splitting reaction catalyst 30 Fuel supply device 41 Air supply device 43, 44 Third flow path 46, 47 Wall 51 Reforming device

Claims (14)

A first flow path through which hydrogen generated by a decomposition reaction of supplied water flows;
A second channel adjacent to the first channel and through which oxygen generated in the first channel flows;
At least a part of the partition wall that separates the first flow path and the second flow path has oxygen permeability that selectively allows the oxygen generated in the first flow path to permeate the second flow path. Characteristic hydrogen production equipment. Fuel gas further circulates in the second flow path,
The hydrogen production apparatus according to claim 1, wherein the fuel gas is burned by the oxygen in the second flow path.   3. The hydrogen production apparatus according to claim 2, wherein combustion heat of the fuel gas is conducted to the first flow path through the partition wall that separates the first flow path and the second flow path.   The hydrogen production apparatus according to claim 1, wherein the fuel gas contains carbon monoxide and hydrogen.   The hydrogen production apparatus according to claim 3, wherein oxygen introduced from the outside further flows through the second flow path.   The hydrogen production apparatus according to any one of claims 3 to 5, wherein a water splitting reaction catalyst is supported on the partition wall separating the first channel and the second channel. . The first flow path is defined by two flat walls arranged at a predetermined interval,
The hydrogen production apparatus according to any one of claims 1 to 6, wherein the partition wall is configured by one of the two flat walls. The other of the two flat walls further constitutes the partition,
The hydrogen production apparatus according to claim 7, wherein the second flow path includes two flow paths that are adjacent to the first flow path through the two flat plate-like walls, respectively. Further comprising a third channel adjacent to the second channel and through which an oxygen-containing gas introduced from the outside flows, and at least a part of the partition wall separating the second channel and the third channel is An oxygen permeable material that selectively allows oxygen contained in the oxygen-containing gas in the third flow path to pass through the second flow path; adjacent to the second flow path; A flow path,
At least a part of the partition wall that separates the second flow path and the third flow path has oxygen permeability that allows oxygen contained in the air in the third flow path to selectively pass through the second flow path. The hydrogen production apparatus according to any one of claims 2 to 8, wherein   The partition wall that separates the second channel and the third channel is a further flat plate-like wall that is disposed at a predetermined distance from the partition wall that separates the first channel and the second channel. The hydrogen production apparatus according to claim 9, comprising:   The hydrogen production apparatus according to claim 1, wherein an inert gas flows through the second flow path.   The hydrogen production apparatus according to claim 1, wherein the second flow path is decompressed.   A hydrogen production system comprising: the hydrogen production apparatus according to any one of claims 1 to 12; and a hydrogen utilization apparatus to which hydrogen produced by the hydrogen production apparatus is supplied. Flowing hydrogen produced by the decomposition reaction of the supplied water to the first flow path;
Circulating the oxygen generated by the decomposition reaction in a second channel adjacent to the first channel,
In the step of circulating oxygen in the second flow path, the oxygen generated by the decomposition reaction is selectively transmitted to the second flow path through a partition wall that separates the first flow path and the second flow path. And a method for producing hydrogen, comprising the step of permeating the water.

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