Hydrogen generation apparatus

Abstract

To provide a technique for reducing the height of a hydrogen generation apparatus while sufficiently securing the length of a flow path between a CO reducer and a CO remover.SOLUTION: A hydrogen generation apparatus 100 comprises: an evaporation unit 121 that evaporates water to generate water vapor; a reformer 122 that generates hydrogen-containing gas from raw material gas and water vapor; a CO reducer 123 disposed downstream of the reformer 122 in the flow direction of the hydrogen-containing gas; a CO remover 124 disposed on a first side in a predetermined direction as viewed from the CO reducer 123 and downstream of the CO reducer 123 in the flow direction of the hydrogen-containing gas; a relay flow path 125 that is a flow path adjacent to the evaporation unit 121 and that guides the hydrogen-containing gas from the CO reducer 123 toward the first side; and a header flow path 154 that guides the hydrogen-containing gas from the relay flow path 125 toward a second side in the predetermined direction and causes the hydrogen-containing gas to flow into the CO remover 124.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a hydrogen generation device. [Background technology]

[0002] Patent Document 1 discloses a hydrogen generation apparatus. The hydrogen generation apparatus includes a first partition wall and a heat-transfer buffer tube whose upper and lower ends are fixed to the first partition wall. The heat-transfer buffer tube has an absorption section in a part of the heat-transfer buffer tube adjacent to the first flow path or the header flow path. The absorption section has a tube diameter larger than the first partition wall but smaller than the heat-transfer buffer tube, and absorbs at least a part of the difference in thermal expansion between the first partition wall and the heat-transfer buffer tube. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2022-124549 Summary of the Invention [Problem to be solved by the invention]

[0004] In a hydrogen generation apparatus of the type described in Patent Document 1, the hydrogen-containing gas generated by a reforming reaction passes through a CO reducer and a CO remover in this order. The optimum temperature of the hydrogen-containing gas in the CO remover is lower than the optimum temperature of the hydrogen-containing gas in the CO reducer. The length of the flow path between the CO reducer and the CO remover is ensured so that the temperature of the hydrogen-containing gas that has passed through the CO reducer is lowered to the optimum temperature.

[0005] On the other hand, there is a need to reduce the height of the hydrogen generator, but there is a trade-off between reducing the height of the hydrogen generator and ensuring a sufficient length of the flow path between the CO reducer and the CO remover.

[0006] The present disclosure provides a technique for reducing the height of a hydrogen generator while ensuring a sufficient length of the flow path between a CO reducer and a CO remover. [Means for solving the problem]

[0007] The present disclosure provides: A heating unit; an evaporation unit that evaporates water using heat from the heating unit to generate water vapor; a reformer that generates a hydrogen-containing gas from the raw material gas and the steam; a CO reducer disposed downstream of the reformer in the flow direction of the hydrogen-containing gas; a CO remover disposed on a first side in a predetermined direction as viewed from the CO reducer and downstream of the CO reducer in a flow direction of the hydrogen-containing gas; a relay flow path adjacent to the evaporator, the relay flow path guiding the hydrogen-containing gas from the CO reducer toward the first side; a header flow path that guides the hydrogen-containing gas from the relay flow path toward a second side in the predetermined direction and causes the hydrogen-containing gas to flow into the CO remover; The present invention provides a hydrogen generating device comprising: [Effects of the Invention]

[0008] According to the present disclosure, the height of the hydrogen generator can be reduced while ensuring a sufficient length of the flow path between the CO reducer and the CO remover. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a longitudinal cross-sectional view of a hydrogen generation device according to a first embodiment. [Figure 2] 10 is a longitudinal cross-sectional view of a hydrogen generation device according to a second embodiment. [Figure 3] 10 is a longitudinal cross-sectional view of a hydrogen generation device according to a third embodiment. [Figure 4] Vertical cross-sectional view of a hydrogen generation device according to a fourth embodiment [Figure 5A] FIG. 1 is a partially enlarged longitudinal cross-sectional view of a hydrogen generation device according to a comparative example. [Figure 5B]FIG. 1 is a partially enlarged vertical cross-sectional view of a hydrogen generation device according to a first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] (Findings that formed the basis of this disclosure) At the time when the present inventors conceived the present disclosure, in a conventional hydrogen generation device (Patent Document 1), the hydrogen-containing gas was cooled to an appropriate temperature while flowing inside the heat transfer buffer cylinder.

[0011] On the other hand, reducing the height of the hydrogen generator requires reducing the height of the heat transfer buffer tube. However, reducing the height of the heat transfer buffer tube (hereinafter referred to as the relay tube) results in an insufficient length of the flow path for cooling the hydrogen-containing gas, which could cause the temperature of the hydrogen-containing gas in the CO remover to exceed the appropriate temperature.

[0012] Based on these findings, the present inventors have come to form the subject of the present disclosure.

[0013] Hereinafter, embodiments will be described in detail with reference to the drawings. However, unnecessary detailed description may be omitted. For example, detailed description of already well-known matters or redundant description of substantially the same configuration may be omitted.

[0014] The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

[0015] (Embodiment 1) Hereinafter, the first embodiment will be described with reference to FIG.

[0016] [1-1.Configuration] FIG. 1 is a vertical cross-sectional view of a hydrogen generation apparatus 100 according to the first embodiment.

[0017] 1, the hydrogen generator 100 includes a heating section 120, an evaporator 121, a reformer 122, a CO reducer 123, a CO remover 124, a relay flow path 125, and a header flow path 154. The arrows in the figure indicate the flow of the hydrogen-containing gas.

[0018] The heating section 120 is a burner that burns combustible gas. The burner burns fuel gas, which is a mixture of combustion air and fuel, and discharges combustion exhaust gas. The burner forms a downward flame. The combustion tube 130 surrounds the heating section 120. The combustion tube 130 is a cylindrical member with a bottom and a central axis parallel to the vertical direction. The combustion tube 130 is surrounded by a partition wall 131.

[0019] The partition wall 131 is a cylindrical member with a bottom and a central axis in the vertical direction. The partition wall 131 is typically cylindrical in shape. The partition wall 131 houses the combustion tube 130. The partition wall 131 is arranged coaxially with the combustion tube 130. A combustion exhaust gas flow path 140 is provided between the combustion tube 130 and the partition wall 131. Heat from the burner of the heating section 120 and heat from the combustion exhaust gas are applied to the partition wall 131. An outlet pipe is provided on the top of the partition wall 131. The combustion exhaust gas is discharged from the outlet pipe. The partition wall 131 is surrounded by an inner tube 132.

[0020] The inner cylinder 132 is a tubular member having a central axis in the vertical direction. The inner cylinder 132 is typically cylindrical in shape. The inner cylinder 132 surrounds the outer periphery of the partition wall 131. The inner cylinder 132 is arranged coaxially with the partition wall 131. The inner cylinder 132 includes an upper portion and a lower portion. The diameter of the lower portion is larger than the diameter of the upper portion. A gap is provided between the inner cylinder 132 and the partition wall 131. The inner cylinder 132 is a metal member. A supply pipe 160 is connected to the inner cylinder 132. A raw material gas containing hydrocarbons and water are supplied to the supply pipe 160. The raw material gas and water are supplied to the evaporation section 121.

[0021] The evaporation section 121 heats the source gas and water with heat from the heating section 120, evaporating the water and generating steam. The evaporation section 121 is provided upstream between the partition wall 131 and the inner cylinder 132. A rod-shaped body 165 is disposed between the inner cylinder 132 and the partition wall 131. The rod-shaped body 165 is bent in a spiral shape. The rod-shaped body 165 has a spiral structure. The spiral structure functions as a partition that spirally separates the area inside the upper portion of the inner cylinder 132 and the area outside the upper structure of the partition wall 131. This defines a space 171. The upper portion of the inner cylinder 132, the upper structure of the partition wall 131, the rod-shaped body 165, and the space 171 constitute the evaporation section 121. The source gas and water flow in the space 171 of the evaporation section 121, and the water evaporates into steam due to heat transferred from the partition wall 131.

[0022] The reformer 122 generates a hydrogen-containing gas from a mixed gas of a raw material gas and steam. The reformer 122 is disposed inside the outer cylinder 133. The reformer 122 is provided downstream of the space between the partition wall 131 and the inner cylinder 132. The reformer 122 is provided in the cylindrical space between the partition wall 131 and the inner cylinder 132. A space 172 is provided between the lower structure 162 of the partition wall 131 and a lower part of the inner cylinder 132. A reforming catalyst is filled in the space 172. The lower structure 162, the lower part of the inner cylinder 132, the space 172, and the reforming catalyst constitute the reformer 122. The reformer 122 is heated by heat transferred from the partition wall 131. The raw material gas and steam flowing out from the evaporation section 121 flow in the space 172 of the reformer 122. The reformer 122 generates a primary hydrogen-containing gas through a reforming reaction from a mixed gas of the raw material gas and steam heated in the evaporation section 121. The primary hydrogen-containing gas is a hydrogen-containing gas that also contains carbon monoxide.

[0023] The outer cylinder 133 is a tubular member having a central axis in the vertical direction. The outer cylinder 133 is typically cylindrical in shape. The outer cylinder 133 is a container that houses various components of the hydrogen generation apparatus 100. The outer cylinder 133 houses the heating section 120, the evaporation section 121, the reformer 122, the CO reducer 123, and the CO remover 124 inside. The outer cylinder 133 is arranged coaxially with the inner cylinder 132. The outer cylinder 133 includes an upper portion, a lower portion, and a bottom portion. The diameter of the lower portion is smaller than the diameter of the upper portion. The outer cylinder 133 is a metal member. The lower portion of the outer cylinder 133 surrounds the lower portion of the inner cylinder 132. There is a gap between the bottom of the outer cylinder 133 and the lower end of the inner cylinder 132, through which the primary hydrogen-containing gas flows. A return flow path 141 is provided between a lower portion of the outer cylinder 133 and a lower portion of the inner cylinder 132. The return flow path 141 redirects the flow of the primary hydrogen-containing gas flowing downward from the reformer 122 upward and guides it to the CO reducer 123.

[0024] The CO reducer 123 is disposed downstream of the reformer 122 in the flow direction of the hydrogen-containing gas. The CO reducer 123 is filled with a CO reduction catalyst. The primary hydrogen-containing gas flowing out from the reformer 122 contains carbon monoxide. The CO reduction catalyst reduces the concentration of carbon monoxide through a transformation reaction, thereby generating a secondary hydrogen-containing gas.

[0025] The relay flow path 125 is a flow path adjacent to the evaporation section 121. The relay flow path 125 is configured to guide the secondary hydrogen-containing gas discharged from the CO reducer 123 upward.

[0026] The header flow path 154 is configured to guide the secondary hydrogen-containing gas downward from the outlet of the relay flow path 125 and cause the hydrogen-containing gas to flow into the CO remover 124.

[0027] The CO remover 124 is provided above the CO reducer 123. The CO remover 124 is disposed downstream of the CO reducer 123 in the flow direction of the secondary hydrogen-containing gas. The CO remover 124 is filled with a CO removal catalyst. The CO remover 124 includes a carbon monoxide removal catalyst that causes a selective oxidation reaction, and reduces the carbon monoxide concentration in the secondary hydrogen-containing gas through the selective oxidation reaction, and discharges the gas as a tertiary hydrogen-containing gas.

[0028] The hydrogen generator 100 further includes a relay tube 134. The relay tube 134 is a member for buffering the heat of the heating unit 120 from being transmitted to the CO reducer 123 and the CO remover 124. The relay tube 134 is arranged coaxially with the inner tube 132. The relay tube 134 surrounds the upper portion of the inner tube 132. The relay tube 134 is configured such that its upper and lower ends are fixed to the inner tube 132. The relay tube 134 is arranged between the inner tube 132 and the outer tube 133. The CO reducer 123 is provided between the relay tube 134 and the outer tube 133. The relay tube 134 extends in the vertical direction. A relay flow path 125 is formed between the inner circumferential surface of the relay tube 134 and the outer circumferential surface of the inner tube 132. An inlet 150 and an outlet 151 of the relay flow path 125 are provided in the relay tube 134. This allows the cooling performance of the secondary hydrogen-containing gas to be determined by the distance between the inlet 150 and the outlet 151 of the relay flow path 125 provided in the relay tube 134 (hereinafter also referred to as the cooling distance).

[0029] The inlet 150 is provided in the relay tube 134 at a position facing the tip of the air supply pipe 136 across the combustion tube 130. The inlet 150 is provided in the relay tube 134 on the lower side in the vertical direction. The outlet 151 is provided in the relay tube 134 on the upper side in the vertical direction. The outlet 151 is provided in the relay tube 134 vertically above the inlet 150. This allows the height of the relay tube 134 to be reduced while ensuring the cooling distance of the relay flow path 125 in the vertical direction, and therefore the height of the hydrogen generator 100 can be reduced.

[0030] The outlet 151 is provided on the side surface of the relay tube 134. The outlet 151 is a through-hole provided in the relay tube 134. A plurality of outlets 151 are provided in the circumferential direction of the relay tube 134. As a result, the secondary hydrogen-containing gas cooled in the relay flow path 125 flows out from the outlet 151 provided on the side surface of the relay tube 134 to the header flow path 154.

[0031] The relay tube 134 has an absorbing section 152. The absorbing section 152 is formed so that its diameter is larger than that of the inner tube 132 and smaller than that of the relay tube 134. The absorbing section 152 is curved toward the outer peripheral surface of the upper part of the inner tube 132. A gap is provided between the absorbing section 152 and the inner tube 132. The absorbing section 152 absorbs at least a part of the difference in thermal expansion between the inner tube 132 and the relay tube 134.

[0032] The relay flow path 125 includes a lower space located below the absorption section 152 and an upper space located above the absorption section 152. The diameter of the upper space of the relay flow path 125 is narrower than the diameter of the lower space.

[0033] The partition member 135 has an inner peripheral end fixed to the relay cylinder 134 and an outer peripheral end fixed to the outer cylinder 133. The partition member 135 is a member having a doughnut disk shape.

[0034] The hydrogen generator 100 further includes an intermediate partition 153. The intermediate partition 153 is disposed at a position facing the outlet 151 of the relay flow path 125. The intermediate partition 153 extends in the vertical direction. The intermediate partition 153 is disposed between the relay tube 134 and the outer tube 131. One vertically upper end of the intermediate partition 153 is fixed to the outer peripheral surface of the inner tube 132. The intermediate partition 153 is configured to guide the secondary hydrogen-containing gas flowing out from the outlet 151 downward in the vertical direction. A header flow path 154 is disposed between the intermediate partition 153 and the relay tube 134. The CO remover 124 is disposed between the intermediate partition 153 and the outer tube 131. This allows the CO remover 124, which is disposed above the CO reducer 123, to be disposed lower than in the past.

[0035] The shape of the header flow path 154 is determined so that the flow direction of the hydrogen-containing gas is reversed at the position of the lower end of the intermediate partition 153 and flows into the CO remover 124. That is, the header flow path 154 includes a first portion 154a that guides the secondary hydrogen-containing gas downward from the outlet of the relay flow path 125, and a second portion 154b that guides the secondary hydrogen-containing gas guided downward upward (see FIG. 5B).

[0036] The first portion 154a of the header flow path 154 is defined by the inner cylinder 132, the relay cylinder 134, and the intermediate partition wall 153. The intermediate partition wall 153 guides the secondary hydrogen-containing gas flowing out from the outlet of the relay flow path 125 downward.

[0037] The second portion 154b of the header flow path 154 is partitioned by the partition member 135 and the outer casing 133. The secondary hydrogen-containing gas guided downward by the intermediate partition 153 is reversed by the partition member 135 at the position of the lower end of the intermediate partition 153. The reversed secondary hydrogen-containing gas is guided upward along the inner casing 133 and flows into the CO remover 124.

[0038] The first flow path 142 is defined by the relay tube 134, the CO reducer 123, the partition member 135, and the outer tube 133. The CO remover 124 is provided between the intermediate partition wall 153 and the outer tube 131.

[0039] An air supply pipe 136 and an outlet pipe are provided in the outer cylinder 133. The air supply pipe 136 is provided at a position above the CO reducer 123 and below the CO remover 124. The outlet pipe is provided at a position above the CO remover 124.

[0040] [1-2. Operation] The operation of the hydrogen generator 100 configured as above will be described below.

[0041] The heating unit 120 burns the combustible gas and discharges the combustion exhaust gas. As the heating unit 120 burns the combustible gas, the heat is transferred to the reformer 122. This allows the reformer 122 to be heated to a desired temperature. The combustion exhaust gas flows upward through the combustion exhaust gas flow path 140 and is discharged to the outside.

[0042] A raw material gas such as city gas and liquid water are supplied to the evaporation section 121, and the water is vaporized by heat transmitted through the partition wall 131, resulting in a mixed gas of the raw material gas and water vapor.

[0043] Since the hydrogen generator 100 has a cylindrical container (outer cylinder 133 in FIG. 1), the mixed gas in the evaporator 121 flows not only in the axial direction but also in the rotational direction around the heating unit 110 as a concentric axis in FIG. 1. Therefore, the reformer 122 also has an approximately doughnut disk shape, and the mixed gas flows into the reformer 122 from the entire circumference.

[0044] The mixed gas of raw material gas and steam that flows into the reformer 122 is heated to 600°C by the heat of the heating unit 120 and is reformed into a hydrogen-containing gas that contains carbon monoxide by the reforming catalyst. At this time, a reaction occurs in which hydrogen and carbon dioxide are produced from methane and water as shown in chemical formula (1), and a reaction occurs in which hydrogen and carbon monoxide are produced from methane and water as shown in chemical formula (2). CH4+ 2H2O → 4H2+ CO2···(1) CH4 + H2O → 3H2 + CO ···(2) However, 600°C is a typical temperature, and the temperature inside the reformer 122 due to the reaction varies depending on the structure, material, and size of the reformer 122. For example, it can range from 400°C to 650°C.

[0045] The primary hydrogen-containing gas flows into the return flow passage 141. The return flow passage 141 has a doughnut disk shape, and the hydrogen-containing gas flows axially upward along the entire circumference of the return flow passage 141 and is supplied to the CO reducer 123.

[0046] The CO reducer 123 reduces the carbon monoxide contained in the primary hydrogen-containing gas flowing out from the reformer 122 and discharges it as a secondary hydrogen-containing gas. Specifically, the carbon monoxide contained in the primary hydrogen-containing gas is reacted with water vapor to generate carbon dioxide and hydrogen through a transformation reaction shown in chemical formula (3) that occurs in the carbon monoxide reduction catalyst, thereby reducing the carbon monoxide. At this time, the temperature of the CO reducer 123 rises to 250°C. CO + H2O → CO2 + H2 (3)

[0047] However, 250°C is a typical temperature, and the temperature inside the CO reducer 123 due to the reaction varies depending on the structure, material, and size of the CO reducer 123. For example, it can vary within a range from 200°C to 300°C.

[0048] The secondary hydrogen-containing gas is discharged from the CO reducer 123 and flows into the first flow path 142. Because the first flow path 142 has a doughnut disk shape, the air injected via the air supply pipe 136 and the secondary hydrogen-containing gas discharged from the CO reducer 123 flow in the circumferential direction of the first flow path 142 and are mixed.

[0049] The secondary hydrogen-containing gas mixed with air flows into relay flow path 125 via inlet 150. Because evaporator 121 and CO reducer 123, and evaporator 121 and CO remover 124 are respectively separated by relay flow path 125, heat exchange between evaporator 121 and CO reducer 123 via inner tube 132 and relay tube 134, and heat exchange between evaporator 121 and CO remover 124 via inner tube 132 and relay tube 134 are suppressed.

[0050] The relay flow path 125 also has a doughnut disk shape, and the presence of the absorption section 152 further restricts the vertical flow of the secondary hydrogen-containing gas inside the relay flow path 125, so that most of the secondary hydrogen-containing gas mixed with the air that has flowed into the relay flow path 125 flows in the circumferential direction of the relay flow path 125. The secondary hydrogen-containing gas is then discharged from the relay flow path 125 through the outlet 151 to the header flow path 154. In the header flow path 154, the secondary hydrogen-containing gas is guided downward by the intermediate partition wall 153. The secondary hydrogen-containing gas that has been guided downward is then guided upward by the partition member 135 and the outer casing 133 and supplied to the CO remover 124.

[0051] The CO remover 124 further reduces the carbon monoxide contained in the secondary hydrogen-containing gas flowing out from the CO reducer 123 and discharges it as a tertiary hydrogen-containing gas. Specifically, a selective oxidation reaction occurs in the carbon monoxide removal catalyst, as shown in chemical formula (4), producing carbon dioxide from carbon monoxide and oxygen, and water from hydrogen and oxygen, as shown in chemical formula (5). At this time, the temperature of the CO remover 124 rises to about 150°C. 2CO + O2 → 2CO2 (4) 2H2 + O2 → 2H2O (5)

[0052] However, 150°C is a typical temperature, and the temperature inside the CO remover 124 due to the reaction varies depending on the structure, material, and size of the CO remover 124. For example, it can vary within a range of 100°C to 180°C.

[0053] The primary hydrogen-containing gas produced by the reforming reaction in the reformer 122 passes through the CO reducer 123 and the CO remover 124 in this order. The optimum temperature of the secondary hydrogen-containing gas in the CO remover 124 is lower than the optimum temperature of the primary hydrogen-containing gas in the CO reducer 123.

[0054] The relay tube 134 is cooled by heat exchange via the inner tube 132 and the relay flow path 125, using the raw material gas and liquid water in the evaporator 121 as cold sources. The secondary hydrogen-containing gas flowing through the relay flow path 125 exchanges heat with the adjacent evaporator 121 and is cooled. The length of the relay flow path 125 between the CO reducer 123 and the CO remover 124 is ensured so that the temperature of the secondary hydrogen-containing gas that has passed through the CO reducer 123 is reduced to an appropriate temperature.

[0055] The cooling performance of the secondary hydrogen-containing gas flowing through the relay flow path 125 is determined by the distance (hereinafter also referred to as the cooling distance) from the inlet 150 provided in the relay tube 134 to the outlet 151 provided vertically above the inlet. With this configuration, the length of the relay flow path 125 can be sufficiently ensured, so that the temperature of the secondary hydrogen-containing gas that has passed through the CO reducer 123 is adjusted to an appropriate temperature.

[0056] [1-3. Comparative Example] The hydrogen generator 100 of the first embodiment will be further described below in comparison with a comparative example of a hydrogen generator 200. The comparative example of the hydrogen generator 200 has the same configuration as the hydrogen generator disclosed in Patent Document 1.

[0057] Fig. 5A is a partially enlarged vertical cross-sectional view of a hydrogen generator 200 of a comparative example. Fig. 5B is a partially enlarged vertical cross-sectional view of the hydrogen generator 100 of Embodiment 1. The arrows in the figure indicate the flow of hydrogen-containing gas.

[0058] The configuration between the CO reducer 223 and the CO remover 224 in the hydrogen generator 200 of the comparative example in Fig. 5A is different from the configuration between the CO reducer 123 and the CO remover 124 in the hydrogen generator 100 of the first embodiment in Fig. 5B. Except for this point, the hydrogen generator 200 of the comparative example has the same configuration as the hydrogen generator 100 of the present embodiment.

[0059] (Comparison of secondary hydrogen-containing gas cooling performance) In the hydrogen generator 200 of the comparative example, the cooling performance of the secondary hydrogen-containing gas flowing through the relay flow path 225 adjacent to the evaporation section 221 is defined by the cooling distance from the inlet 250 provided in the relay tube 234 to the outlet 251 provided vertically above the inlet 250. The cooling distance of the hydrogen generator 200 of the comparative example is defined as L1.

[0060] In the hydrogen generator 100 of the first embodiment, the cooling performance of the secondary hydrogen-containing gas flowing through the relay flow path 125 adjacent to the evaporation section 121 is defined by the cooling distance from the inlet 150 provided in the relay tube 134 to the outlet 151 provided vertically above the inlet 150. The cooling distance of the hydrogen generator 100 of the first embodiment is defined as L2.

[0061] The cooling distance L1 of the hydrogen generator 200 of the comparative example is equal to the cooling distance L2 of the hydrogen generator 100 of the first embodiment. The cooling performance of the hydrogen generator 200 of the comparative example is comparable to that of the hydrogen generator 100 of the first embodiment. Therefore, in the hydrogen generator 200 of the comparative example, the secondary hydrogen-containing gas is cooled to an appropriate temperature while flowing inside the relay tube 234 (relay flow path 225). Similarly, in the hydrogen generator 100 of the first embodiment, the secondary hydrogen-containing gas is cooled to an appropriate temperature while flowing inside the relay tube 134 (relay flow path 125).

[0062] (Comparing the height of hydrogen generators) In the hydrogen generator 200 of the comparative example, the CO remover 224 is disposed above the outlet 251 of the relay tube 234 and the header flow path 254. Specifically, the CO remover 224 is provided between the relay tube 234 and the outer tube 233. The header flow path 254 is configured by the relay tube 234, the outer tube 233, and the partition member 235. As a result, the secondary hydrogen-containing gas cooled in the relay flow path 225 is discharged from the relay flow path 225 through the outlet 251 to the header flow path 254. The secondary hydrogen-containing gas is guided upward in the header flow path 254 by the partition member 235 and the outer tube 233, and is supplied to the CO remover 224.

[0063] In the comparative example, in order to reduce the height of the hydrogen generator 200, it is necessary to reduce the height of the relay tube 234. However, when the height of the relay tube 234 is reduced, the length of the relay flow path 225 becomes insufficient, and there is a risk that the temperature of the secondary hydrogen-containing gas in the CO remover 224 will exceed the appropriate temperature.

[0064] In contrast, the hydrogen generation apparatus 100 of the first embodiment includes an intermediate partition 153, and the CO remover 124 is disposed at the same height as the outlet 151 of the relay cylinder 134 and the header flow path 154. Specifically, the CO remover 124 is provided between the intermediate partition 153 and the outer cylinder 133. The header flow path 154 is configured by the inner cylinder 132, the relay cylinder 134, the intermediate partition 153, the CO remover 124, the partition member 135, and the outer cylinder 133.

[0065] The header flow path 154 includes a first portion 154a that guides the secondary hydrogen-containing gas downward from the outlet of the relay flow path 125, and a second portion 154b that guides the secondary hydrogen-containing gas guided downward upward. The first portion 154a of the header flow path 154 is partitioned by the inner cylinder 132, the relay cylinder 134, and the intermediate partition wall 153. The second portion 154b of the header flow path 154 is partitioned by the partition member 135 and the outer cylinder 133.

[0066] As a result, in the hydrogen generator 100 of the first embodiment, the secondary hydrogen-containing gas cooled in the relay flow path 125 is discharged from the relay flow path 125 to the header flow path 154 via the outlet 151. The secondary hydrogen-containing gas is guided vertically downward by the intermediate partition 153 in the first portion 154a of the header flow path 154. Then, the secondary hydrogen-containing gas guided downward is reversed at the position of the lower end of the intermediate partition 153 by the partition member 135 in the second portion 154b of the header flow path 154 and guided upward, and flows into the CO remover 124. As a result, in the hydrogen generator 100 of the first embodiment, the CO remover 124 can be arranged lower than the CO remover 224 of the comparative example.

[0067] Furthermore, in the hydrogen generator 100 of the first embodiment, the height of the relay tube 134 is reduced compared to the relay tube 234 of the comparative example. Furthermore, since the cooling performance of the secondary hydrogen-containing gas is determined by the cooling distance from the inlet 150 to the outlet 151 of the relay tube 134, reducing the height of the relay tube 134 does not shorten the cooling distance L2. The temperature of the secondary hydrogen-containing gas in the CO remover 124 can be adjusted to an appropriate temperature. Therefore, according to the first embodiment, the height of the hydrogen generator 100 can be reduced while ensuring a sufficient length of the flow path between the CO reducer 123 and the CO remover 124.

[0068] (Embodiment 2) Hereinafter, the second embodiment will be described with reference to Fig. 2. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

[0069] Fig. 2 is a longitudinal sectional view of the hydrogen generator 100A of the second embodiment. In Fig. 2, the configuration of the header flow path 154A of the hydrogen generator 100A of the second embodiment is different from the configuration of the header flow path 154 of the hydrogen generator 100 of the first embodiment (Fig. 1). Except for this point, the hydrogen generator 100A of the second embodiment has the same configuration as the hydrogen generator 100 of the first embodiment. The arrows in the figure indicate the flow of hydrogen-containing gas.

[0070] The second embodiment is similar to the first embodiment (FIG. 1) in that the header flow path 154A has an outlet 151 provided on the side surface of the relay tube 134. On the other hand, in the first embodiment, one end on the upper side in the vertical direction of the intermediate partition wall 153 is fixed to the outer peripheral surface of the inner tube 132, whereas in the second embodiment, one end on the upper side in the vertical direction of the intermediate partition wall 153 is fixed to the outer peripheral surface of the relay tube 134.

[0071] (Embodiment 3) Hereinafter, the third embodiment will be described with reference to Fig. 3. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

[0072] Fig. 3 is a vertical cross-sectional view of the hydrogen generator 100B of the third embodiment. In Fig. 3, the configuration of the header flow path 154B of the hydrogen generator 100B of the third embodiment is different from the configuration of the header flow path 154 of the hydrogen generator 100 of the first embodiment (Fig. 1). Except for this point, the hydrogen generator 100B of the third embodiment has the same configuration as the hydrogen generator 100 of the first embodiment. The arrows in the figure indicate the flow of hydrogen-containing gas.

[0073] The third embodiment is similar to the first embodiment (FIG. 1) in that one vertically upper end of the intermediate partition 153 is fixed to the outer peripheral surface of the inner cylinder 132. Meanwhile, in the first embodiment, the outlet 151 in the header flow path 154B is provided on the side surface of the relay cylinder 134 (FIG. 1). In contrast, in the third embodiment, the outlet 151 in the header flow path 154 is provided on the upper end portion of the relay cylinder 134 (see FIG. 3). As a result, the secondary hydrogen-containing gas flowing out from the outlet 151 provided on the upper end portion of the relay cylinder 134 is blown onto the intermediate partition 153 and guided downward. Furthermore, the cooling distance is longer than in a configuration in which the outlet 151 is provided on the side surface of the relay cylinder 134, and therefore the cooling performance is improved.

[0074] (Fourth embodiment) Fig. 4 is a longitudinal sectional view of the hydrogen generator 100C of the fourth embodiment. In Fig. 4, the configuration of the header flow path 154C of the hydrogen generator 100C of the fourth embodiment is different from the configuration of the header flow path 154 of the hydrogen generator 100 of the first embodiment (Fig. 1). Except for this point, the hydrogen generator 100C of the fourth embodiment has the same configuration as the hydrogen generator 100 of the first embodiment. The arrows in the figure indicate the flow of hydrogen-containing gas.

[0075] The fourth embodiment differs from the first embodiment (FIG. 1) in that the outlet 151 is provided at the upper end of the relay cylinder 134 in the header flow path 154C. The fourth embodiment also differs from the first embodiment (FIG. 1) in that one vertically upper end of the intermediate partition 153 is fixed to the outer peripheral surface of the relay cylinder 134. This results in a longer cooling distance than in a configuration in which the outlet 151 is provided on the side surface of the relay cylinder 134, thereby improving cooling performance.

[0076] (Variation) In the first to fourth embodiments, the CO remover 124 is disposed vertically above the CO reducer 123, but the configuration is not limited to this as long as the CO remover 124 is disposed on the "first side" in the "predetermined direction" as viewed from the CO reducer 123. Furthermore, the header flow path 154 is configured to guide the secondary hydrogen-containing gas downward in the vertical direction from the relay flow path 125 and cause the secondary hydrogen-containing gas to flow into the CO remover 124, but the configuration is not limited to this as long as the header flow path 154 guides the secondary hydrogen-containing gas from the relay flow path 125 toward the "second side" in the "predetermined direction" and causes the secondary hydrogen-containing gas to flow into the CO remover 124.

[0077] The hydrogen generators 100, 100A, 100B, and 100C of Embodiments 1 to 4 may be arranged upside down. That is, in the above-described embodiments, the "predetermined direction" is the vertical direction, the "first side" is the upper side, and the "second side" is the lower side with respect to the definition of the directions, but the "first side" may be the lower side and the "second side" may be the upper side.

[0078] Alternatively, the hydrogen generators 100, 100A, 100B, and 100C of the first to fourth embodiments may be disposed horizontally. That is, the "predetermined direction" may be the horizontal direction. In this case, the "first side" may be the right side and the "second side" may be the left side, or the "first side" may be the left side and the "second side" may be the right side. The horizontal direction is a direction perpendicular to the vertical direction.

[0079] In the first to fourth embodiments, the relay flow path 125 includes a lower space located below the absorption section 152 and an upper space located above the absorption section 152 (see FIGS. 1 to 4). The diameter of the upper space of the relay flow path 125 is narrower than the diameter of the lower space. In contrast, in the hydrogen generator 200 of the comparative example, the diameters of the upper and lower spaces of the relay flow path 225 are approximately the same (see FIG. 5A). When the cross-sectional area of ​​the relay flow path 125 is narrowed, the secondary hydrogen-containing gas flowing inside flows near the inner cylinder 132. This increases the heat transfer coefficient, resulting in higher heat exchange efficiency. As a result, the secondary hydrogen-containing gas flowing through the relay flow path 125 is more easily cooled than in the comparative example.

[0080] (Other embodiments) As described above, the first to fourth embodiments have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to these, and can also be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. Furthermore, it is also possible to combine the components described in the first to fourth embodiments above to create new embodiments.

[0081] The above description of the embodiments discloses the following techniques.

[0082] (Technology 1) A heating unit; an evaporation unit that evaporates water using heat from the heating unit to generate water vapor; a reformer that generates a hydrogen-containing gas from the raw material gas and the steam; a CO reducer disposed downstream of the reformer in the flow direction of the hydrogen-containing gas; a CO remover disposed on a first side in a predetermined direction as viewed from the CO reducer and downstream of the CO reducer in a flow direction of the hydrogen-containing gas; a relay flow path adjacent to the evaporator, the relay flow path guiding the hydrogen-containing gas from the CO reducer toward the first side; a header flow path that guides the hydrogen-containing gas from the relay flow path toward a second side in the predetermined direction and causes the hydrogen-containing gas to flow into the CO remover; A hydrogen generating device comprising:

[0083] According to this configuration, the hydrogen-containing gas discharged from the CO reducer flows through the relay flow path and is guided toward a first side (e.g., the upper side) in a predetermined direction as viewed from the CO reducer. At this time, the hydrogen-containing gas flowing through the relay flow path exchanges heat with the adjacent evaporator and is cooled. Thereafter, the hydrogen-containing gas is guided from the relay flow path toward a second side (e.g., the lower side) in the predetermined direction by the header flow path and flows into the CO remover. This allows, for example, the CO remover, which is usually located above the CO reducer, to be located lower than in the past, thereby reducing the height of the hydrogen generation apparatus. Furthermore, the cooling performance of the hydrogen-containing gas depends on the length of the relay flow path between the CO reducer and the CO remover. According to this configuration, the length of the relay flow path can be sufficiently ensured, so that the temperature of the hydrogen-containing gas that has passed through the CO reducer is adjusted to an appropriate temperature.

[0084] (Technology 2) The hydrogen generation device according to technology 1 further includes a partition wall surrounding the heating unit, an inner cylinder surrounding the partition wall, an outer cylinder surrounding the inner cylinder, and a relay cylinder disposed between the inner cylinder and the outer cylinder and extending in the predetermined direction, wherein the relay flow path is formed between an outer peripheral surface of the inner cylinder and an inner peripheral surface of the relay cylinder, and an inlet and an outlet of the relay flow path are provided in the relay cylinder. According to this configuration, the cooling performance of the hydrogen-containing gas can be defined by the distance (cooling distance) between the inlet and the outlet of the relay flow path provided in the relay cylinder.

[0085] (Technology 3) The hydrogen generation device according to Technology 1 or Technology 2, wherein the inlet of the relay flow path is provided in the relay tube on the second side in the predetermined direction, and the outlet of the relay flow path is provided in the relay tube on the first side in the predetermined direction. According to this configuration, for example, the height of the relay tube can be reduced while ensuring the distance (cooling distance) between the inlet and outlet in the vertical direction of the relay flow path, and therefore the height of the hydrogen generation device can be reduced.

[0086] (Technology 4) The hydrogen generation apparatus according to Technology 2 or Technology 3 further includes an intermediate partition wall disposed at a position facing the outlet of the relay flow path and extending in the predetermined direction, the header flow path is formed between the relay tube and the intermediate partition wall, and the CO remover is provided between the intermediate partition wall and the outer tube. According to this configuration, for example, the CO remover disposed above the CO reducer can be disposed lower than in the past.

[0087] (Technology 5) The hydrogen generation apparatus according to technique 4, wherein the shape of the header flow path is determined so that the flow direction of the hydrogen-containing gas is reversed at the position of the second end of the intermediate partition and flows into the CO remover. According to this configuration, for example, the CO remover, which is disposed above the CO reducer, can be disposed lower than in the past.

[0088] (Technology 6) The hydrogen generation device according to technique 3, wherein the outlet of the relay flow path is provided on a side surface of the relay tube. According to this configuration, the hydrogen-containing gas flowing out from the outlet provided on the side surface of the relay tube is blown onto the intermediate partition wall and guided to the second side (e.g., the lower side).

[0089] (Technology 7) The hydrogen generation device according to Technical Problem 3, wherein the outlet of the relay flow path is provided at the end of the first side of the relay tube. According to this configuration, the hydrogen-containing gas flowing out from the outlet provided at the end of the first side (e.g., upper side) of the relay tube is blown onto the intermediate partition wall and guided to the second side (e.g., lower side). In addition, the relay flow path is longer than in a configuration in which the outlet is provided on the side surface of the relay tube. [Industrial Applicability]

[0090] The technology of the present disclosure is useful for a hydrogen generation device equipped with a reformer, a CO reducer, and a CO remover. [Explanation of symbols]

[0091] 100, 100A, 100B, 100C Hydrogen Generator 120 Heating section 121 Evaporation section 122 Reformer 123 CO reducer 124 CO remover 125 Relay Channel 130 Combustion tube 131 Bulkhead 132 Inner cylinder 133 Outer cylinder 134 Relay Cylinder 135 Partition members 136 Air supply pipe 140 Combustion gas flow path 141 Return flow path 142 First Channel 150 Entrance 151 Exit 152 Absorption section 153 Intermediate wall 154 Header flow path 160 Supply pipe 162 Lower structure 165 Rod-shaped body 171, 172 space 200 Hydrogen generator

Claims

1. A heating unit; an evaporation unit that evaporates water using heat from the heating unit to generate water vapor; a reformer that generates a hydrogen-containing gas from the raw material gas and the steam; a CO reducer disposed downstream of the reformer in the flow direction of the hydrogen-containing gas; a CO remover disposed on a first side in a predetermined direction as viewed from the CO reducer and downstream of the CO reducer in a flow direction of the hydrogen-containing gas; a relay flow path adjacent to the evaporator, the relay flow path guiding the hydrogen-containing gas from the CO reducer toward the first side; a header flow path that guides the hydrogen-containing gas from the relay flow path toward a second side in the predetermined direction and causes the hydrogen-containing gas to flow into the CO remover; A hydrogen generating device comprising:

2. A partition wall surrounding the heating unit; an inner cylinder surrounding the partition wall; an outer cylinder surrounding the inner cylinder; a relay tube disposed between the inner tube and the outer tube and extending in the predetermined direction; Further provided with the relay flow path is formed between an outer peripheral surface of the inner cylinder and an inner peripheral surface of the relay cylinder, An inlet and an outlet of the relay flow path are provided in the relay tube. The hydrogen generation device according to claim 1 .

3. the inlet of the relay flow path is provided in the relay tube on the second side in the predetermined direction, the outlet of the relay flow path is provided in the relay tube on the first side in the predetermined direction; The hydrogen generation device according to claim 2 .

4. an intermediate partition wall disposed at a position facing the outlet of the relay flow path and extending in the predetermined direction; The header flow path is formed between the relay tube and the intermediate partition wall, The CO remover is provided between the intermediate partition and the outer cylinder. The hydrogen generation device according to claim 2 .

5. the shape of the header flow path is determined so that the flow direction of the hydrogen-containing gas is reversed at the position of the second end of the intermediate partition and flows into the CO remover. The hydrogen generation device according to claim 4 .

6. The outlet of the relay flow path is provided on a side surface of the relay tube. The hydrogen generator according to claim 3 .

7. The outlet of the relay flow path is provided at the first end of the relay tube. The hydrogen generator according to claim 3 .

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