JP2023118143A - hydrogen generator - Google Patents

Abstract

To provide a hydrogen generator equipped with a reformer and an evaporation section, which can shorten its overall length and reduce material cost while suppressing deterioration of a reforming catalyst caused by infiltration of liquid water into the reformer even if quantity of liquid water supplied to the evaporation section is large.SOLUTION: A hydrogen generator according to the present disclosure is equipped with a structure in which a convex part and a concave part are formed on inner and outer surfaces of an inner cylinder in a top-reverse integrated manner over the entire circumference, the convex part of the outer surface of the inner cylinder is in close contact with inner and outer surfaces of an outer cylinder over the entire circumference, and a lower part of the evaporation section is blocked.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to hydrogen generators.

Patent Document 1 describes a water trap for trapping liquid water discharged from the evaporator in a hydrogen generator with a multi-cylindrical structure, in which an evaporator for evaporating water is arranged above a reformer surrounding a heating unit. It is disclosed that the possibility of deterioration of the reforming catalyst due to splashing of liquid water on the reforming catalyst packed in the reformer can be reduced by further providing the part.

This hydrogen generator has a bottomed cylindrical shape with a vertical center axis, an inner cylinder whose inner peripheral surface is heated by combustion exhaust gas from a heating unit, and a cylindrical shape with a vertical center axis and an outer periphery of the inner cylinder. and an outer cylinder surrounding the .

The evaporator is formed by arranging a helically bent bar in the upper part between the inner cylinder and the outer cylinder to form a helical flow path, and the reformer is composed of the inner cylinder and the outer cylinder. The water trap part is formed by filling the lower part of the gap with the reforming catalyst, and the water trap part has an L-shaped cross section at a place above the reformer and below the evaporator on the outer peripheral surface of the inner cylinder A shaped and annular member is attached.

JP 2008-19159 A

The present disclosure is a multi-cylindrical hydrogen generator in which an evaporator is arranged above the reformer, and the overall length is shortened while suppressing the deterioration of the reforming catalyst due to the infiltration of liquid water into the reformer. and provide a hydrogen generator capable of reducing material costs.

The hydrogen generator according to the present disclosure includes a heating unit, a combustion cylinder, an inner cylinder, an outer cylinder, a heating unit storage cylinder, a first partition, a flue gas flow path, an evaporator, a reformer, and a communication port.

The heating unit is configured to burn the combustible gas and discharge flue gas. The combustion cylinder has a central axis in the vertical direction and is configured to surround the outer circumference of the heating section. The inner cylinder has a cylindrical shape with a central axis in the vertical direction, and is configured to surround the outer circumference of the combustion cylinder. The outer cylinder has a cylindrical shape with a central axis in the vertical direction, and is configured to surround the outer circumference of the inner cylinder.

The heating unit housing cylinder is a bottomed cylinder having a vertical central axis, houses the combustion cylinder, and is configured such that the upper end is joined to the lower end of the inner cylinder or the lower end of the outer cylinder. . The first partition wall has a bottomed cylindrical shape with a central axis in the vertical direction, and is configured to accommodate the inner cylinder, the outer cylinder, and the heating unit housing cylinder. The combustion exhaust gas flow path is formed between the cylinder composed of the inner cylinder and the heating unit storage cylinder and the combustion cylinder, and is configured to flow the combustion exhaust gas upward.

The evaporator is formed between the inner cylinder and the outer cylinder, heats the raw material gas and water with heat transmitted through the inner cylinder, evaporates the water, and unevaporated liquid water stays in the lower part. is configured to

The reformer is formed by filling a reforming catalyst under the evaporator, and the heat transmitted through the heating unit storage cylinder converts the mixed gas of the raw material gas and water vapor into carbon monoxide through a reforming reaction. A primary hydrogen-containing gas is configured to be generated.

A plurality of communication ports are formed in the circumferential direction of the outer cylinder at a position higher than the water level of the liquid water remaining in the lower part of the evaporator without evaporating, so that the raw material gas and water vapor flow out from the evaporator to the reformer. It is configured to allow

In the vicinity of the lower end of the inner cylinder, the inner cylinder is formed so that an annular concave portion recessed in the outer peripheral direction is formed on the entire inner peripheral surface, and an annular convex portion protruding in the outer peripheral direction is formed on the outer peripheral surface along the entire peripheral surface. The wall of the cylinder is bent in the outer peripheral direction over the entire circumference, and the protrusions on the outer peripheral surface of the inner cylinder are in close contact with the inner peripheral surface of the outer cylinder over the entire circumference so that unevaporated liquid water stays at the bottom of the evaporator. are doing.

In the hydrogen generator according to the present disclosure, the liquid water remaining in the lower part of the evaporating part is inclined with respect to the vertical direction in addition to the side wall part adjacent to the inner peripheral side of the liquid water parallel to the vertical direction in the inner cylinder. By adopting a structure adjacent to the combustion exhaust gas flow path through the convex portion adjacent to the lower side of the water, compared with the conventional configuration in which an annular member having an L-shaped cross section is provided on the outer peripheral surface of the inner cylinder. Since the heat transfer area from the high-temperature flue gas to the liquid water is wider than the liquid water retention amount, the evaporation of the liquid water is promoted more than before, and the total length of the evaporator is shorter than before. However, the liquid water can be sufficiently evaporated.

As a result, it is possible to reduce the total length of the hydrogen generator in the vertical direction while suppressing the deterioration of the reforming catalyst caused by the intrusion of liquid water into the reformer. Further, when the overall length of the hydrogen generator is shortened, the heat insulating material covering the outer peripheral surface of the hydrogen generator and the housing for housing the hydrogen generator become smaller, so the material cost of the hydrogen generator can be reduced.

Schematic diagram of the hydrogen generator in Embodiment 1 Schematic configuration diagram of a hydrogen generator in Embodiment 2 Schematic configuration diagram of a hydrogen generator in another embodiment

(Knowledge, etc. on which this disclosure is based)
At the time when the inventors came up with the present disclosure, hydrogen was generated by a steam reforming reaction from a hydrocarbon source gas such as city gas, and impurities such as carbon monoxide (CO) produced as a by-product were removed. There is a technique for generating hydrogen-rich, hydrogen-containing gas that can be applied to the fuel gas of a fuel cell power generator, etc., by doing so.

This technology for generating hydrogen-rich hydrogen-containing gas is a reformer that has a multi-cylindrical overall shape, a heating unit equipped with a burner at the center, and a reforming catalyst that fills the periphery of the heating unit. is provided, and above the reformer, a hydrogen generator is provided in which an evaporating section for heating the source gas and water by heat transfer from the heating section is provided.

If the water supplied to the evaporator does not completely evaporate into steam in the course of passing through the evaporator, the liquid water discharged from the evaporator enters the reformer and splashes on the reforming catalyst. There was a problem that the

Therefore, in the industry, in order to solve this problem, a space in which the liquid water stays in the lower part of the evaporator and a communication port in the upper part of the space in which the liquid water stays are provided. was retained, and only the raw material gas and water vapor were allowed to flow out from the communication port, thereby suppressing the intrusion of liquid water into the reformer.

Therefore, in consideration of fluctuations in the level of the stagnant liquid water, it has been common practice to increase the height of the cylinder part that constitutes the evaporator, in order to provide a margin.

Under such circumstances, the inventors have found that shortening the overall length of the hydrogen generator in the height direction reduces the material cost and makes it possible to manufacture the hydrogen generator at low cost. The idea was to shorten the length of the hydrogen generator by shortening the evaporator, which was conventionally designed to have a sufficiently long height relative to the level of the remaining liquid water.

In order to realize the idea, the inventors have found that the amount of raw material gas and water fluctuates, and when a large amount of raw material gas and water are supplied, the amount of heating of the stagnant liquid water is insufficient. Therefore, we discovered that there is a problem that the level of the stagnant liquid water rises, and part of the liquid water flows out from the communication port and enters the reformer. I have come up with a topic.

Therefore, according to the present disclosure, the lower part of the inner cylinder, which forms the evaporating part together with the outer cylinder, is integrally formed with convex parts and concave parts over the entire circumference so that unevaporated liquid water stays in the lower part of the evaporating part. The liquid water remaining in the lower part of the evaporator is also heated from the protrusions by forming the protrusions on the outer peripheral surface of the inner cylinder in close contact with the inner peripheral surface of the outer cylinder over the entire circumference. By increasing the heat transfer area to the liquid water with respect to the amount of retention in the reformer and promoting evaporation, it is possible to reduce the overall length while suppressing the deterioration of the reforming catalyst caused by the intrusion of liquid water into the reformer. , to provide a hydrogen generator capable of reducing material costs.

Hereinafter, embodiments will be described in detail with reference to the drawings. However, more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters or redundant descriptions of substantially the same configurations may be omitted.

It should be noted that the accompanying drawings and the following description are provided to allow those skilled in the art to fully understand the present disclosure and are not intended to limit the claimed subject matter thereby.

(Embodiment 1)
Embodiment 1 will be described below with reference to FIG.

[1-1. composition]
As shown in FIG. 1, the hydrogen generator 100 includes a heating unit 120, an evaporating unit 121, a reformer 122, a CO reducer 123, a combustion cylinder 130, an inner cylinder 131, an outer cylinder 132, It has a heating unit storage cylinder 133 , a first partition 134 , a second partition 135 , a hydrogen-containing gas discharge pipe 136 , a flue gas channel 140 , a return channel 141 , and a communication port 150 .

The heating unit 120 is arranged on the inner peripheral side of a combustion cylinder 130 having a central axis in the vertical direction, and includes a burner that burns combustible gas mixed with combustion air and discharges combustion exhaust gas, and a combustible gas in the burner. and a combustion air supply pipe for supplying combustion air to the burner. The burners of heating section 120 are configured to produce downward flames.

Raw material gas (city gas or LP gas) can be used as the combustible gas. A fuel gas (anode off-gas) discharged from the fuel cell power generation device can be used.

Combustion cylinder 130 has a central axis in the vertical direction, has a cylindrical shape surrounding the outer periphery of heating section 120 , and is arranged coaxially with heating section 120 . The combustion cylinder 130 allows the combustion exhaust gas to flow downward in the vertical direction on the inner peripheral side of the combustion cylinder 130, 130 is a member for causing the flue gas to flow upward in the vertical direction.

The lower end of the combustion cylinder 130 is positioned at substantially the same height as the lower end of the reformer 122 or vertically below the lower end of the reformer 122 . The lower end of the combustion cylinder 130 is positioned vertically above the bottom of a bottomed cylindrical heating unit storage cylinder 133 that surrounds the combustion cylinder 130 and is arranged coaxially with the combustion cylinder 130 .

In the hydrogen generator 100, after the flue gas generated by the combustion of the burner of the heating unit 120 flows downward along the inner peripheral surface of the combustion tube 130 along the inner peripheral side of the combustion tube 130, it enters the heating unit storage tube 133. It passes through the gap between the bottom and the lower end of the combustion tube 130, exits to the outer peripheral side of the combustion tube 130, folds upward, and heats while exchanging heat with the reforming catalyst of the reformer 122 via the heating unit storage tube 133. After flowing upward through the flue gas flow path 140 between the heating unit housing cylinder 133 and the combustion cylinder 130 along the inner peripheral surface of the heating unit housing cylinder 133, the water and raw material gas in the evaporating unit 121 pass through the inner cylinder 131. While exchanging heat with It is configured to be discharged to the outside of the hydrogen generator 100 from a combustion exhaust gas outlet pipe provided in the.

The inner cylinder 131 is a substantially cylindrical metal member having a central axis in the vertical direction. placed in

The inner cylinder 131 and the outer cylinder 132 form a helical flow path for helically flowing the raw material gas containing hydrocarbons and water.

In the portion where the spiral flow path is formed in the inner cylinder 131, the outer peripheral surface of the inner cylinder 131 contacts the inner peripheral surface of the outer cylinder 132, and the outer peripheral surface of the inner cylinder 131 contacts the inner peripheral surface of the outer cylinder 132. The cross section of the cylinder wall of the inner cylinder 131 in the axial direction is wavy so that the surface and the non-contact portion are alternately repeated in the axial direction of the inner cylinder 131 .

In the portion of the inner cylinder 131 where the helical flow path is formed, the cylinder wall is formed to have a corrugated cross-section in the axial direction of the inner cylinder 131, and the helical unevenness in the axial direction is formed on the cylinder wall. is formed in

The inner cylinder 131 forms a flue gas flow path 140 with the combustion cylinder 130 . A heating unit storage tube 133 is joined to the lower end of the inner tube 131 so as to extend the flue gas flow path 140 below the inner tube 131 .

The heating unit housing cylinder 133 is a bottomed cylindrical metal member having a vertical central axis, and is configured to house the combustion cylinder 130 with its upper end joined to the lower end of the inner cylinder 131 . The heating unit storage cylinder 133 has an inner diameter larger than the outer diameter of the combustion cylinder 130 , and is arranged so as to surround the outer peripheral surface of the combustion cylinder 130 and be coaxial with the combustion cylinder 130 below the inner cylinder 131 in the vertical direction.

There is a gap between the bottom portion of the heating unit housing tube 133 and the lower end portion of the combustion tube 130 through which the combustion exhaust gas that has flowed along the inner peripheral side of the combustion tube 130 flows to the outer peripheral side of the combustion tube 130 .

The outer cylinder 132 is a cylindrical metal member having a central axis in the vertical direction, and is arranged so as to surround the outer peripheral surface of the inner cylinder 131 and be coaxial with the inner cylinder 131 . In the portion where the spiral flow path is formed in the outer cylinder 132 , the inner peripheral surface of the outer cylinder 132 contacts the outer peripheral surface of the inner cylinder 131 and the inner peripheral surface of the outer cylinder 132 contacts the outer peripheral surface of the inner cylinder 131 . The surface and the non-contact portion are alternately repeated in the axial direction of the outer cylinder 132 .

The second partition wall 135 has a cylindrical side surface that has an inner diameter larger than the outer diameter of the outer cylinder 132 and is arranged coaxially with the outer cylinder 132 to surround the outer cylinder 132. and a donut disk-shaped upper surface portion that is connected and whose inner peripheral end is joined to the outer peripheral surface of the outer cylinder 132 .

The second partition wall 135 has a lower end portion of the side surface portion positioned substantially at the same height as the lower end portion of the combustion cylinder 130 or vertically lower than the lower end portion of the reformer 122, and has a doughnut-shaped upper surface. is located above the communication port 150 in the vertical direction and below the lower end of the CO reducer 123 in the vertical direction.

A reforming catalyst that generates a primary hydrogen-containing gas (a hydrogen-containing gas containing carbon monoxide) by a reforming reaction from a mixed gas of raw material gas and water vapor is filled between the heating unit housing cylinder 133 and the second partition wall 135. It is

Between the inner cylinder 131 and the outer cylinder 132, the portion where the helical flow path is formed is heated by the heat transmitted from the high-temperature flue gas through the inner cylinder 131 to the raw material gas containing hydrocarbons and water. A portion filled with a reforming catalyst below the evaporator 121 serves as a reformer 122 .

The spiral flow path of the evaporating section 121 is formed so that the inner and outer peripheral surfaces of the inner cylinder 131 are integrally formed with spiral protrusions and recesses extending in the axial direction (vertical direction). In the outer peripheral direction of the unevenness of the outer peripheral surface The projecting convex portion is formed so as to be in close contact with the inner peripheral surface of the outer cylinder 132 .

In the lower part of the evaporating part 121 , an annular groove (recess) recessed in the outer peripheral direction is formed on the inner peripheral surface of the inner cylinder 131 by expanding the portion near the lower end of the inner cylinder 131 . An annular protrusion projecting in the outer peripheral direction is formed over the entire circumference in a portion of the outer peripheral surface corresponding to the annular groove (recess) on the inner peripheral surface, and the annular protrusion on the outer peripheral surface of the inner cylinder 131 extends outward. It is in close contact with the inner peripheral surface of the cylinder 132 over the entire circumference to close the lower portion of the evaporating section 121 .

The annular groove (recess) on the inner peripheral surface of the portion near the lower end of the inner cylinder 131 has the deepest portion at the center in the vertical direction of the groove, and the width of the groove in the vertical direction increases toward the deepest portion of the groove. is narrowed.

In the annular groove (recess) on the inner peripheral surface of the portion near the lower end of the inner cylinder 131, the inner diameter of the inner cylinder 131 decreases upward from the deepest part of the groove, and the inner cylinder 131 decreases downward from the deepest part of the groove. It is a shape with a smaller inner diameter.

The annular protrusion on the outer peripheral surface of the portion near the lower end of the inner cylinder 131 has an outer diameter that decreases upward from a portion that is in close contact with the inner peripheral surface of the outer cylinder 132 over the entire circumference. The inner cylinder 131 has a shape in which the outer diameter of the inner cylinder 131 decreases as it goes downward from the part that is in close contact with the inner peripheral surface over the entire circumference.

The lower part of the evaporating part 121 is processed so that the inner peripheral surface and the outer peripheral surface of the inner cylinder 131 are integrally formed with a convex portion and a concave portion over the entire circumference, and the convex portion protruding in the outer peripheral direction of the unevenness. is closed so as to be in close contact with the inner peripheral surface of the outer cylinder 132 over the entire circumference, the unevaporated liquid water stays in the lower part of the evaporating part 121 .

A portion near the lower end of the inner cylinder 131 is formed with an annular recess that is recessed in the outer peripheral direction along the entire circumference of the inner peripheral surface, and an annular convex portion that protrudes in the outer peripheral direction is formed on the outer peripheral surface along the entire circumference. A cylinder wall of the cylinder 131 is bent in the outer peripheral direction over the entire circumference.

A plurality of communication ports 150 are formed in the circumferential direction of the outer cylinder 132 at positions higher than the water level of the liquid water staying in the lower part of the evaporator 121 in order to allow the source gas and water vapor to flow out from the evaporator 121 to the reformer 122 . is provided.

The position where the communication port is provided is the position where the convex portion of the outer peripheral surface of the inner cylinder 131 is in close contact with the inner peripheral surface of the outer cylinder 132 over the entire circumference and closes the lower part of the evaporating section 121, considering the level of the liquid water that remains. 5 mm above the vertical direction. A convex portion on the outer peripheral surface of the inner cylinder 131 is in close contact with the inner peripheral surface of the outer cylinder 132 over the entire circumference, and the part where the lower part of the evaporating section 121 is blocked is airtightly joined.

The spiral flow path of the evaporating section 121 may be formed by arranging a spiral round bar instead of processing the inner cylinder 131 to provide it. As the spiral round bar, for example, a round bar bent into a spiral shape such as a coiled spring (coil spring) may be used. By installing a round bar bent in a helical shape like a coil spring (coil spring) so as to be in close contact with the outer peripheral surface of the inner cylinder 131 and the inner peripheral surface of the outer cylinder 132, the helical shape of the evaporating part 121 is formed. A channel can be formed.

The reformer 122 is formed by filling a reforming catalyst between the heating unit housing cylinder 133 and the second partition wall 135, and the heat transmitted through the heating unit housing cylinder 133 converts the mixed gas of the raw material gas and steam into a mixed gas. from the reforming reaction to produce a primary hydrogen-containing gas containing carbon monoxide. The reforming catalyst filled in the reformer 122 is a granular platinum-based catalyst with a diameter of 2 to 3 mm.

In the present embodiment, a platinum-based catalyst is used as the reforming catalyst, but the reforming catalyst is not limited to a platinum-based catalyst. A nickel-based catalyst may also be used.

Directly below the portion filled with the reforming catalyst, a vent hole with a diameter of 1 mm, which is smaller than the particle size of the reforming catalyst that supports the reforming catalyst from below, is formed so that the reforming catalyst does not fall. A doughnut board-shaped plate having a ventilation structure is disposed between the heating unit storage cylinder 133 and the second partition wall 135 .

Immediately above the portion filled with the reforming catalyst, even if the hydrogen generator 100 is turned upside down during manufacture (the direction of gravity when the hydrogen generator 100 is used is reversed) In order to prevent the reforming catalyst from moving toward the evaporating part 121, the reforming catalyst is covered from above with a donut disk structure in which a vent hole having a diameter of 1 mm smaller than the particle diameter of the reforming catalyst is formed. A shaped plate is arranged between the heating unit storage cylinder 133 and the second partition 135 .

A supply pipe for supplying raw material gas and water to the evaporator 121 is connected to a portion of the outer cylinder 132 above the location where the spiral flow path is arranged.

The first partition 134 has an inner diameter larger than the outer diameter of the second partition 135, is arranged coaxially with the outer cylinder 132 and the second partition 135, and surrounds the outer peripheral surfaces of the outer cylinder 132 and the second partition 135. It is a metal member having a bottomed cylindrical side surface and a doughnut-shaped upper surface whose outer peripheral end is connected to the upper end of the side surface and whose inner peripheral end is joined to the outer peripheral surface of the outer cylinder 132 .

The first partition 134 forms a return flow path 141 with the second partition 135, and the CO reduction filled with a carbon monoxide reduction catalyst between the outer cylinder 132 positioned above the second partition 135. A device 123 is constructed. Between the bottom of the first partition 134 and the lower end of the second partition 135 there is a gap through which the primary hydrogen-containing gas flows.

The bottom of the first partition 134 is larger than the bottom of the heating unit storage cylinder 133 , and the first partition 134 is configured to accommodate the outer cylinder 132 , the second partition 135 and the heating unit storage cylinder 133 .

The portion adjacent to the outer peripheral side of the evaporating section 121 between the first partition 134 and the outer cylinder 132 reduces the concentration of carbon monoxide contained in the primary hydrogen-containing gas flowing out of the reformer 122 by a chemical reaction. The CO reducer 123 is filled with a carbon monoxide reduction catalyst that generates secondary hydrogen-containing gas.

The carbon monoxide reduction catalyst filled in the CO reducer 123 is a granular Cu—Zn catalyst with a diameter of 2 to 3 mm. In the present embodiment, a Cu—Zn-based catalyst is used as the carbon monoxide reduction catalyst, but the carbon monoxide reduction catalyst is not limited to the Cu—Zn-based catalyst. A Ru-based catalyst may be used as the reducing catalyst.

Immediately below the portion filled with the carbon monoxide reduction catalyst, a particle size smaller than the carbon monoxide reduction catalyst that supports the carbon monoxide reduction catalyst from below so that the filled carbon monoxide reduction catalyst does not fall. A donut disk-shaped plate having a ventilation structure with a 1 mm diameter ventilation hole is disposed between the outer cylinder 132 and the first partition 134 .

Immediately above the portion filled with the carbon monoxide reduction catalyst, even if the hydrogen generator 100 is turned upside down during manufacture (vertical direction of gravity when the hydrogen generator 100 is used) In order to prevent the carbon monoxide reduction catalyst from flowing out even if the carbon monoxide reduction catalyst is turned upside down, a ventilation structure in which a vent hole having a diameter of 1 mm smaller than the particle diameter of the carbon monoxide reduction catalyst covering the carbon monoxide reduction catalyst is formed. A doughnut-shaped plate is arranged between the outer cylinder 132 and the first partition 134 .

The return channel 141 is formed between the first partition 134 and the second partition 135 and below the CO reducer 123 in the vertical direction so that the primary hydrogen-containing gas that has flowed out of the reformer 122 flows upward. is configured to

The hydrogen-containing gas discharge pipe 136 is provided vertically above the CO reducer 123 on the side surface of the first partition 134, and configured to discharge the secondary hydrogen-containing gas that has flowed out of the CO reducer 123 to the outside. It is

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

The heating unit 120 burns the combustible gas and discharges flue gas. Heat from the combustible gas is transferred to the reformer 122 by the heating unit 120 burning the combustible gas. Thereby, the reformer 122 can be raised to a desired temperature.

Raw material gas such as city gas and liquid water are supplied to the evaporating part 121, and in the process of passing through the spiral flow path, the water is evaporated by the heat transmitted through the inner cylinder 131, and the raw material gas and water vapor are produced. It becomes a mixed gas.

At this time, since the amount of raw material gas and the amount of water supplied to the evaporator 121 are larger than the amount of water evaporated in the spiral flow path, even if unevaporated liquid water remains, Since the liquid water stays in the lower part of the evaporator 121 and only the source gas and water vapor flow out of the evaporator 121 through the communication port 150, the liquid water is prevented from entering the reformer 122. FIG.

In addition, the liquid water remaining in the lower part of the evaporating part 121 is adjacent to the flue gas flow path through the convex part located vertically below in addition to the inner cylinder 131 on the side of the liquid water, so that the high temperature flue gas It is possible to increase the heat transfer area from the to the liquid water, sufficiently evaporate the remaining liquid water, and lower the level of the remaining liquid water.

As a result, even if the total length of the evaporating section 121 is short, the level of the stagnant liquid water does not rise to the height of the communication port 150, and the outflow of the liquid water from the communication port 150 is suppressed.

In the present embodiment, city gas containing desulfurized methane as a main component is used as the raw material gas. Also, the amount of water supplied to the evaporator 121 is set so that the amount of oxygen molecules that is three times the amount of carbon atoms in the average composition of the raw material gas is included.

In the present embodiment, since city gas containing methane as a main component is used as the raw material gas, the amount of water required for the presence of 3 moles of water vapor per 1 mole of methane to be supplied is 121. That is, the amount of water that makes the steam carbon ratio (S/C ratio) 3 is supplied to the evaporator 121 .

Since the hydrogen generator 100 has a multi-cylindrical structure, the reformer 122 also has a substantially donut shape (cylindrical shape with a hole in the center), and the raw material gas and steam flow from the entire top surface of the reformer 122 . The mixed gas flows into reformer 122 .

The mixed gas of the raw material gas and steam that has flowed into the reformer 122 is heated to 600° C. by the heat of the heating unit 120 and reformed into a primary hydrogen-containing gas containing carbon monoxide by the reforming catalyst. At this time, a reaction to produce hydrogen and carbon dioxide from methane and water as shown in (Chem. 1) and a reaction to produce hydrogen and carbon monoxide from methane and water as shown in (Chem. 2) are taking place. .

ただし、６００℃は典型的な温度であって、反応による改質器１２２内の温度は、改質器１２２の構造や材質、大きさにも依存して変わる。例えば、４００℃～６５０℃の範囲で変動し得る。

However, 600.degree. For example, it can range from 400°C to 650°C.

The primary hydrogen-containing gas flows from reformer 122 into return channel 141 . The return channel 141 has a donut shape, and the primary hydrogen-containing gas flows upward in the axial direction along the entire circumference of the return channel 141 and is supplied to the CO reducer 123 . The CO reducer 123 also has a doughnut-like shape, and the primary hydrogen-containing gas flows into the CO reducer 123 from the entire circumference of the lower surface thereof.

The CO reducer 123 reduces carbon monoxide contained in the primary hydrogen-containing gas and discharges it as a secondary hydrogen-containing gas. Specifically, the carbon monoxide and water vapor contained in the primary hydrogen-containing gas are reacted with each other to produce carbon dioxide and hydrogen by the transformation reaction shown in (Chemical 3) occurring in the carbon monoxide reduction catalyst, and the concentration of carbon monoxide is carbon monoxide is reduced to about 0.1 to 0.2%.

At this time, part of the heat generated by the transformation reaction is transferred to the evaporator 121 via the outer cylinder 132, so that the CO reducer 123 is maintained at 250° C., which is suitable for chemical reaction.

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 from 200°C to 300°C.

ＣＯ低減器１２３から排出された二次水素含有ガスは、水素含有ガス排出管１３６から水素生成装置１００の外部に排出された後に、燃料電池発電装置などの水素利用機器に供給される。

The secondary hydrogen-containing gas discharged from the CO reducer 123 is discharged from the hydrogen-containing gas discharge pipe 136 to the outside of the hydrogen generator 100, and then supplied to a hydrogen utilization device such as a fuel cell power generator.

The combustion exhaust gas generated by the combustion of the burner of the heating unit 120 flows downward along the inner peripheral surface of the combustion tube 130 and then flows downward along the inner peripheral side of the combustion tube 130, and then passes through the bottom of the heating unit storage tube 133 and the combustion tube 130. After coming out to the outer peripheral side of the combustion cylinder 130 through the gap with the lower end, it is folded back upward and flows through the combustion exhaust gas flow path 140 between the combustion cylinder 130 and the heating unit storage cylinder 133. When reforming 122, and then heat-exchanged with the evaporator 121 when passing through the flue gas flow path 140 between the combustion cylinder 130 and the inner cylinder 131, and is provided in the upper part of the inner cylinder 131. It is discharged to the outside of the hydrogen generator 100 from the combustion exhaust gas outlet pipe.

[1-3. effect]
As described above, the hydrogen generator 100 according to the present embodiment includes the heating unit 120, the evaporating unit 121, the reformer 122, the combustion cylinder 130, the inner cylinder 131, the outer cylinder 132, and the heating unit housing. It has a cylinder 133 , a first partition 134 , a flue gas flow path 140 and a communication port 150 .

The heating unit 120 is configured to burn combustible gas and discharge flue gas. Combustion cylinder 130 has a central axis in the vertical direction and is configured to surround the outer circumference of heating section 120 . The inner cylinder 131 has a cylindrical shape with a central axis in the vertical direction, and is configured to surround the outer circumference of the combustion cylinder 130 . The outer cylinder 132 has a cylindrical shape with a central axis in the vertical direction, and is configured to surround the outer circumference of the inner cylinder 131 .

The heating unit housing cylinder 133 is a bottomed cylinder having a vertical center axis, and is configured to house the combustion cylinder 130 by joining the upper end to the lower end of the inner cylinder 131 . The first partition 134 has a bottomed cylindrical shape with a central axis in the vertical direction, and is configured to accommodate the inner cylinder 131 , the outer cylinder 132 , and the heating unit housing cylinder 133 .

The combustion exhaust gas flow path 140 is formed between the cylinder composed of the inner cylinder 131 and the heating unit storage cylinder 133 and the combustion cylinder 130, and is configured to flow the combustion exhaust gas upward.

The evaporator 121 is formed between the inner cylinder 131 and the outer cylinder 132, heats the source gas and water with heat transmitted through the inner cylinder 131, evaporates the water, and converts the unevaporated liquid water into is configured to stay at the bottom.

The reformer 122 is formed by filling a reforming catalyst below the evaporator 121, and the heat transmitted through the heating unit housing cylinder 133 converts the mixed gas of the raw material gas and steam into monoxide through a reforming reaction. It is configured to produce a primary hydrogen-containing gas containing carbon.

A plurality of communication ports 150 are formed in the circumferential direction of the outer cylinder 132 at a position higher than the water level of the liquid water remaining in the lower portion of the evaporating section 121 without evaporating. It is configured to flow out to the reformer 122 .

A portion near the lower end of the inner cylinder 131 is formed with an annular recess that is recessed in the outer peripheral direction along the entire circumference of the inner peripheral surface, and an annular convex portion that protrudes in the outer peripheral direction is formed on the outer peripheral surface along the entire circumference. The cylinder wall of the cylinder 131 is bent in the outer peripheral direction over the entire circumference, and the protrusions on the outer peripheral surface of the inner cylinder 131 are curved on the inner peripheral surface of the outer cylinder 132 so that the unevaporated liquid water stays in the lower part of the evaporating part 121 . and adheres all around.

In the above configuration, the liquid water remaining in the lower part of the evaporating part 121 is not only on the side wall part adjacent to the inner peripheral side of the liquid water parallel to the vertical direction in the inner cylinder 131, but also on the side wall part that is inclined with respect to the vertical direction. By adopting a structure adjacent to the combustion exhaust gas flow path 140 via the convex portion adjacent to the lower side, compared to the conventional configuration in which an annular member having an L-shaped cross section is provided on the outer peripheral surface of the inner cylinder Since the heat transfer area from the high-temperature flue gas to the liquid water is larger than the liquid water retention amount, the evaporation of the liquid water is promoted more than before, and the total length (vertical length) of the evaporator 121 is increased. ) can be made shorter than before, the liquid water can be sufficiently evaporated.

As a result, it is possible to reduce the overall length of the hydrogen generator 100 in the vertical direction while suppressing the deterioration of the reforming catalyst caused by the infiltration of liquid water into the reformer 122 . If the overall length of the hydrogen generator 100 is shortened, the heat insulating material that covers the outer peripheral surface of the hydrogen generator 100 and the housing that houses the hydrogen generator 100 become smaller, so the material cost of the hydrogen generator 100 can be reduced.

As in the present embodiment, the evaporator 121 in the hydrogen generator 100 is formed in the inner and outer peripheral surfaces of the inner cylinder 131 vertically above the communication port 150 in a spiral shape toward the axial direction. The protrusions and recesses of the inner cylinder 131 are formed integrally with each other, and the protrusions on the outer peripheral surface of the inner cylinder 131 are brought into close contact with the inner peripheral surface of the outer cylinder 132 to prevent water from flowing between the inner cylinder 131 and the outer cylinder 132. A spiral channel may be formed for vaporization.

As a result, a spiral flow path for evaporating water is easily formed by bulging (hydroforming) or the like in the evaporating section 121 above the communication port 150 in the vertical direction without increasing the number of parts. can.

Furthermore, the inner periphery of the outer cylinder 132 is vertically below the communication port 150 so that the evaporating part 121 has a spiral flow path and the unevaporated liquid water stays in the lower part of the evaporating part 121. The formation of the annular protrusion on the outer peripheral surface of the inner cylinder 131 that is in close contact with the surface can be simultaneously formed by one bulging process. Therefore, the evaporating section 121 can be manufactured easily, and the manufacturing cost can be reduced.

In addition, in the present embodiment, hydrogen generator 100 may include CO reducer 123 , second partition 135 , hydrogen-containing gas discharge pipe 136 , and return channel 141 .

The CO reducer 123 is formed by filling a portion adjacent to the outer peripheral side of the evaporating section 121 with a carbon monoxide reducing catalyst between the first partition 134 and the outer cylinder 132 . It is configured to reduce the concentration of carbon monoxide contained in the hydrogen-containing gas through a chemical reaction and discharge it as a secondary hydrogen-containing gas.

The second partition wall 135 has a donut-shaped side portion having an inner diameter larger than the outer diameter of the outer cylinder 132 , an outer peripheral end connected to the upper end of the side portion, and an inner peripheral end joined to the outer peripheral surface of the outer cylinder 132 . The reformer 122 is formed by filling a reforming catalyst between the heating unit housing tube 133 and the second partition wall 135 .

The return flow path 141 is formed between the first partition 134 and the second partition 135 and configured to flow the primary hydrogen-containing gas that has flowed out of the reformer 122 upward (to the CO reducer 123). .

The hydrogen-containing gas discharge pipe 136 is provided in the first partition wall 134 and configured to discharge the secondary hydrogen-containing gas to the outside.

As a result, the reformer 122 can receive heat uniformly from the heating section 120 in the circumferential direction, and the reforming reaction can be efficiently performed. Furthermore, the concentration of carbon monoxide contained in the primary hydrogen-containing gas produced in the reformer 122 can be reduced by a chemical reaction (transformation reaction) in the CO reducer 123 .

Therefore, when the hydrogen generator 100 supplies fuel gas to the fuel cell power generation device, the hydrogen-containing gas whose carbon monoxide concentration is reduced by the CO reducer 123 can be supplied to the fuel cell power generation device as the fuel gas. It is possible to suppress deterioration in the performance of the fuel cell power generation device due to carbon oxide.

In addition, without increasing the total length of the vertical direction of the hydrogen generator 100, the reforming catalyst of the reformer 122 is set to a temperature suitable for the reforming catalyst, and the carbon monoxide reduction catalyst of the CO reducer 123 is chemically reacted. It becomes possible to set the temperature suitable for (modification reaction).

In addition, in the present embodiment, the hydrogen generator 100 is configured so that the protrusions on the outer peripheral surface of the inner cylinder 131 are completely aligned with the inner peripheral surface of the outer cylinder 132 so that the unevaporated liquid water stays in the lower part of the evaporating part 121 . You may join the location which adhere|attaches over the circumference|pipe airtightly.

As a result, the liquid water remaining in the lower portion of the evaporator 121 passes through the portion where the convex portion on the outer peripheral surface of the inner cylinder 131 and the inner peripheral surface of the outer cylinder 132 are in close contact over the entire circumference, and enters the reformer 122. can be suppressed. Therefore, deterioration of the reforming catalyst caused by intrusion of liquid water into the reformer 122 can be suppressed.

Further, in the present embodiment, the hydrogen generator 100 may be configured by integrating the inner cylinder 131 and the heating unit storage cylinder 133 .

As a result, the portion where the convex portion on the outer peripheral surface of the inner cylinder 131 is in close contact with the inner peripheral surface of the outer cylinder 132 over the entire circumference is airtight so that the non-evaporated liquid water stays in the lower portion of the evaporating portion 121. A structure can be employed in which the joining work can be performed from the outer peripheral direction of the outer cylinder 132 . Therefore, the manufacturing of the hydrogen generator 100 can be simplified.

(Embodiment 2)
Embodiment 2 will be described below with reference to FIG.

[2-1. composition]
As shown in FIG. 2, the hydrogen generator 200 includes a heating unit 220, an evaporating unit 221, a reformer 222, a CO reducer 223, a combustion cylinder 230, an inner cylinder 231, an outer cylinder 232, It has a heating unit storage tube 233 , a first partition 234 , a second partition 235 , a hydrogen-containing gas discharge pipe 236 , a flue gas flow path 240 , a return flow path 241 , and a communication port 250 .

The heating unit 220 is arranged on the inner peripheral side of a combustion cylinder 230 having a central axis in the vertical direction, and includes a burner that burns combustible gas mixed with combustion air and discharges combustion exhaust gas, and a combustible gas in the burner. and a combustion air supply pipe for supplying combustion air to the burner. The burners of heating section 220 are configured to produce downward flames.

Raw material gas (city gas or LP gas) can be used as the combustible gas. A fuel gas (anode off-gas) discharged from the fuel cell power generation device can be used.

Combustion cylinder 230 has a central axis in the vertical direction, is cylindrical and surrounds the outer circumference of heating section 220 , and is arranged coaxially with heating section 220 . The combustion cylinder 230 allows the combustion exhaust gas to flow downward in the vertical direction on the inner peripheral side of the combustion cylinder 230, 230 is a member for causing the flue gas to flow upward in the vertical direction.

The lower end of the combustion cylinder 230 is positioned at substantially the same height as the lower end of the reformer 222 or vertically below the lower end of the reformer 222 . The lower end of the combustion cylinder 230 is positioned vertically above the bottom of a bottomed cylindrical heating unit storage cylinder 233 that surrounds the combustion cylinder 230 and is arranged coaxially with the combustion cylinder 230 .

In the hydrogen generator 200, the flue gas generated by the combustion of the burner of the heating unit 220 flows downward along the inner peripheral surface of the combustion tube 230, and then flows into the heating unit housing tube 233. It goes out to the outer peripheral side of the combustion tube 230 through the gap between the bottom part and the lower end part of the combustion tube 230 and folds upward, and heats while exchanging heat with the reforming catalyst of the reformer 222 via the heating unit storage tube 233 . After flowing upward through the flue gas flow path 240 between the heating unit housing cylinder 233 and the combustion cylinder 230 along the inner peripheral surface of the heating unit housing cylinder 233, the water and raw material gas in the evaporating unit 221 pass through the inner cylinder 231. While exchanging heat with It is configured to be discharged to the outside of the hydrogen generator 200 from a combustion exhaust gas outlet pipe provided in the.

The inner cylinder 231 is a substantially cylindrical metal member having a central axis in the vertical direction. placed in

Between the inner cylinder 231 and the outer cylinder 232, a spirally bent round bar like a coil spring is arranged in order to spirally flow the raw material gas containing hydrocarbons and water. ing.

The place where the spiral round bar is arranged between the inner cylinder 231 and the combustion cylinder 230 serves as an evaporator 221 through which the raw material gas containing hydrocarbons and water pass while being heated by the heat transferred from the inner cylinder 231 . ing.

The inner cylinder 231 forms a flue gas flow path 240 with the combustion cylinder 230 . In the vicinity of the lower end of the inner cylinder 231 , the portion where the outer peripheral surface is inclined so that the diameter of the inner cylinder 231 decreases as it goes downward extends the combustion exhaust gas flow path 240 below the inner cylinder 231 . In the vicinity of the upper end of the heating unit storage cylinder 233, the inner peripheral surface is in close contact with the inclined portion so that the diameter of the heating unit storage cylinder 233 increases upward.

The heating unit storage cylinder 233 has an inner diameter larger than the outer diameter of the combustion cylinder 230, and its upper end is joined to the lower end of the outer cylinder 232, and surrounds the outer peripheral surface of the combustion cylinder 230 below the outer cylinder 232 in the vertical direction, It is arranged so as to be coaxial with the combustion tube 230 and configured to accommodate the combustion tube 230 .

The heating unit housing cylinder 233 is a bottomed cylindrical metal member that has a central axis in the vertical direction and is integrally formed with the outer cylinder 232. is connected to the upper end of the side portion and the outer peripheral end is joined to the lower end of the outer cylinder 232, and the bottom portion is connected to the lower end of the side portion.

Between the bottom portion of the heating unit housing tube 233 and the lower end portion of the combustion tube 230, there is a gap through which the combustion exhaust gas that has flowed downward on the inner peripheral side of the combustion tube 230 flows to the outer peripheral side of the combustion tube 230. .

The outer cylinder 232 is a cylindrical metal member having a central axis in the vertical direction, and is arranged so as to surround the outer peripheral surface of the inner cylinder 231 and be coaxial with the inner cylinder 231 . A spiral flow path is formed between the outer cylinder 232 and the inner cylinder 231 .

The second partition wall 235 has a cylindrical side surface that has an inner diameter larger than the outer diameter of the outer cylinder 232 and is arranged coaxially with the outer cylinder 232 to surround the outer cylinder 232. and a donut disk-shaped upper surface portion that is connected and whose inner peripheral end is joined to the outer peripheral surface of the outer cylinder 232 .

The second partition wall 235 has a lower end portion of the side surface portion positioned substantially at the same height as the lower end portion of the combustion cylinder 230 or vertically lower than the lower end portion of the reformer 222, and has a doughnut-shaped upper surface. is located above the communication port 250 in the vertical direction and below the lower end of the CO reducer 223 in the vertical direction.

A reforming catalyst that generates a primary hydrogen-containing gas (a hydrogen-containing gas containing carbon monoxide) by a reforming reaction from a mixed gas of raw material gas and steam is filled between the heating unit housing cylinder 233 and the second partition wall 235. It is

Between the inner cylinder 231 and the outer cylinder 232, the portion where the helical flow path is formed is heated by the heat transmitted from the high-temperature combustion exhaust gas through the inner cylinder 231 to the raw material gas containing hydrocarbons and water. It is an evaporator 221 through which the light passes through.

A primary hydrogen-containing gas (a hydrogen-containing gas containing carbon monoxide) is produced by a reforming reaction from a mixed gas of raw material gas and water vapor below the evaporating unit 221 and between the heating unit storage cylinder 233 and the second partition wall 235 . A reformer 222 is filled with the reforming catalyst to be produced.

The helical flow path of the evaporating section 221 is formed by arranging a helical round bar between the inner cylinder 231 and the outer cylinder 232 . As the spiral round bar, for example, a round bar bent into a spiral shape such as a coiled spring (coil spring) may be used. By installing a round bar bent in a helical shape like a coil spring (coil spring) so as to be in close contact with the outer peripheral surface of the inner cylinder 231 and the inner peripheral surface of the outer cylinder 232, the helical shape of the evaporating part 221 is formed. A channel can be formed.

In the lower part of the evaporating part 221 , an annular groove (recess) recessed in the outer peripheral direction is formed on the inner peripheral surface of the inner cylinder 231 over the entire circumference by expanding the portion near the lower end of the inner cylinder 231 . An annular protrusion projecting in the outer peripheral direction is formed over the entire circumference in a portion of the outer peripheral surface corresponding to the annular groove (recess) on the inner peripheral surface, and the annular protrusion on the outer peripheral surface of the inner cylinder 231 extends outward. It is in close contact with the inner peripheral surface of the cylinder 232 over the entire circumference to close the lower portion of the evaporating section 221 .

The annular groove (recess) on the inner peripheral surface of the portion near the lower end of the inner cylinder 231 has the deepest portion at the center in the vertical direction of the groove, and the width of the groove in the vertical direction increases toward the deepest portion of the groove. is narrowed.

In the annular groove (recess) on the inner peripheral surface of the inner cylinder 231 near the lower end, the inner diameter of the inner cylinder 231 decreases upward from the deepest part of the groove, and the inner cylinder 231 decreases downward from the deepest part of the groove. It is a shape with a smaller inner diameter.

The annular convex portion on the outer peripheral surface of the portion near the lower end of the inner cylinder 231 has an outer diameter of the inner cylinder 231 that decreases upward from a portion that is in close contact with the inner peripheral surface of the outer cylinder 232 over the entire circumference. The inner cylinder 231 has a shape in which the outer diameter of the inner cylinder 231 decreases as it goes downward from the part that is in close contact with the inner peripheral surface over the entire circumference.

The lower part of the evaporating part 221 is processed so that the inner peripheral surface and the outer peripheral surface of the inner cylinder 231 are integrally formed with a convex part and a concave part over the entire circumference, and the convex part protrudes in the outer peripheral direction of the unevenness. is closed so as to be in close contact with the entire circumference of the inner peripheral surface of the outer cylinder 232 , unevaporated liquid water stays in the lower part of the evaporating section 221 .

A portion near the lower end of the inner cylinder 231 is formed with an annular recess that is recessed in the outer peripheral direction along the entire circumference of the inner peripheral surface, and an annular convex portion that protrudes in the outer peripheral direction is formed on the outer peripheral surface along the entire circumference. A cylinder wall of the cylinder 231 is bent in the outer peripheral direction over the entire circumference.

In order to allow the raw material gas and steam to flow out from the evaporator 221 to the reformer 222, a plurality of communication ports 250 are formed in the circumferential direction of the outer cylinder 232 at positions higher than the water level of the liquid water staying in the lower part of the evaporator 221. is provided.

The position where the communication port is provided is the position where the convex portion on the outer peripheral surface of the inner cylinder 231 is in close contact with the inner peripheral surface of the outer cylinder 232 over the entire circumference and closes the lower portion of the evaporating section 221 in consideration of the level of the liquid water that remains. 5 mm above the vertical direction. A convex portion on the outer peripheral surface of the inner cylinder 231 is in close contact with the inner peripheral surface of the outer cylinder 232 over the entire circumference, and the portion where the lower portion of the evaporating section 221 is blocked is airtightly joined.

Instead of arranging a spiral round bar between the inner cylinder 231 and the outer cylinder 232, the spiral flow path of the evaporating part 221 is arranged such that the inner and outer peripheral surfaces of the inner cylinder 231 are arranged in the axial direction ( In the vertical direction), the inner cylinder 231 is processed so that a spiral convex portion and a concave portion are integrally formed (the outer peripheral surface of the inner cylinder 231 is formed with unevenness like a male screw, and the inner cylinder 231 is The helical shape of the evaporating section 221 is formed by forming protrusions and recesses such as female threads on the peripheral surface so that the protrusions protruding in the outer peripheral direction of the protrusions and recesses on the outer peripheral surface are in close contact with the inner peripheral surface of the outer cylinder 232 . can be formed.

The reformer 222 is formed by filling a reforming catalyst between the heating unit housing cylinder 233 and the second partition wall 235, and the heat transmitted through the heating unit housing cylinder 233 converts the mixed gas of the raw material gas and steam into a mixed gas. from the reforming reaction to produce a primary hydrogen-containing gas containing carbon monoxide. The reforming catalyst filled in the reformer 222 is a granular platinum-based catalyst with a diameter of 2 to 3 mm.

In the present embodiment, a platinum-based catalyst is used as the reforming catalyst, but the reforming catalyst is not limited to a platinum-based catalyst. A nickel-based catalyst may also be used.

Directly below the portion filled with the reforming catalyst, a vent hole with a diameter of 1 mm, which is smaller than the particle size of the reforming catalyst that supports the reforming catalyst from below, is formed so that the reforming catalyst does not fall. A doughnut board-shaped plate having an air-permeable structure is arranged between the heating unit storage cylinder 233 and the second partition wall 235 .

Immediately above the portion filled with the reforming catalyst, even if the hydrogen generator 200 is turned upside down during manufacture (the direction of gravity when the hydrogen generator 200 is used is reversed) In order to prevent the reforming catalyst from moving toward the evaporating part 221, the reforming catalyst is covered from above with a donut disk structure in which a vent hole having a diameter of 1 mm, which is smaller than the particle diameter of the reforming catalyst, is formed. A shaped plate is arranged between the heating unit storage cylinder 233 and the second partition wall 235 .

A supply pipe for supplying the raw material gas and water to the evaporator 221 is connected to a portion of the outer cylinder 232 above the location where the spiral flow path is arranged.

The first partition 234 has an inner diameter larger than the outer diameter of the second partition 235, is arranged coaxially with the outer cylinder 232 and the second partition 235, and surrounds the outer peripheral surfaces of the outer cylinder 232 and the second partition 235. It is a metal member having a bottomed cylindrical side surface and a doughnut-shaped upper surface whose outer peripheral end is connected to the upper end of the side surface and whose inner peripheral end is joined to the outer peripheral surface of the outer cylinder 232 .

The first partition 234 forms a return flow path 241 with the second partition 235, and between the outer cylinder 232 positioned above the second partition 235 is a CO reduction filled with a carbon monoxide reduction catalyst. A device 223 is constructed. Between the bottom of the first partition 234 and the lower end of the second partition 235 there is a gap through which the primary hydrogen-containing gas flows.

The bottom of the first partition 234 is larger than the bottom of the heating unit storage tube 233 , and the first partition 234 is configured to accommodate the outer tube 232 , the second partition 235 and the heating unit storage tube 233 .

The portion adjacent to the outer peripheral side of the evaporating section 221 between the first partition 234 and the outer cylinder 232 reduces the concentration of carbon monoxide contained in the primary hydrogen-containing gas flowing out of the reformer 222 by a chemical reaction. The CO reducer 223 is filled with a carbon monoxide reduction catalyst that generates secondary hydrogen-containing gas.

The carbon monoxide reduction catalyst filled in the CO reducer 223 is a granular Cu—Zn catalyst with a diameter of 2 to 3 mm. In the present embodiment, a Cu—Zn-based catalyst is used as the carbon monoxide reduction catalyst, but the carbon monoxide reduction catalyst is not limited to the Cu—Zn-based catalyst. A Ru-based catalyst may be used as the reducing catalyst.

Immediately below the portion filled with the carbon monoxide reduction catalyst, a particle size smaller than the carbon monoxide reduction catalyst that supports the carbon monoxide reduction catalyst from below so that the filled carbon monoxide reduction catalyst does not fall. A donut disk-shaped plate having a ventilation structure with a 1 mm diameter ventilation hole is disposed between the outer cylinder 232 and the first partition wall 234 .

Immediately above the portion filled with the carbon monoxide reduction catalyst, even if the hydrogen generator 200 is turned upside down during manufacture (up and down in the direction of gravity when the hydrogen generator 200 is in use) In order to prevent the carbon monoxide reduction catalyst from flowing out even if the carbon monoxide reduction catalyst is turned upside down, a ventilation structure in which a vent hole having a diameter of 1 mm smaller than the particle diameter of the carbon monoxide reduction catalyst covering the carbon monoxide reduction catalyst is formed. A doughnut-shaped plate is arranged between the outer cylinder 232 and the first partition wall 234 .

The return channel 241 is formed between the first partition 234 and the second partition 235 and below the CO reducer 223 in the vertical direction so that the primary hydrogen-containing gas that has flowed out of the reformer 222 flows upward. is configured to

The hydrogen-containing gas discharge pipe 236 is provided vertically above the CO reducer 223 on the side surface of the first partition 234, and is configured to discharge the secondary hydrogen-containing gas that has flowed out of the CO reducer 223 to the outside. It is

[2-2. motion]
The operation and function of the hydrogen generator 200 configured as described above will be described below.

The heating unit 220 burns the combustible gas and discharges flue gas. Heat is transferred to the reformer 222 by burning the combustible gas in the heating unit 220 . Thereby, the reformer 222 can be raised to a desired temperature.

Raw material gas such as city gas and liquid water are supplied to the evaporating part 221, and in the process of passing through the spiral flow path, the water is evaporated by the heat transmitted through the inner cylinder 231, and the raw material gas and water vapor are produced. It becomes a mixed gas.

At this time, since the amount of raw material gas and the amount of water supplied to the evaporator 221 are larger than the amount of water evaporated in the spiral flow path, even if unevaporated liquid water remains, Since the liquid water stays in the lower part of the evaporator 221 and only the source gas and water vapor flow out of the evaporator 221 through the communication port 250, the liquid water is prevented from entering the reformer 222. FIG.

In addition to the inner cylinder 231 on the side of the liquid water, the liquid water remaining in the lower part of the evaporating part 221 is adjacent to the combustion exhaust gas flow path via the convex part located vertically below, so that the high temperature combustion exhaust gas It is possible to increase the heat transfer area from the to the liquid water, sufficiently evaporate the remaining liquid water, and lower the level of the remaining liquid water.

As a result, even if the total length of the evaporating section 221 is short, the level of the stagnant liquid water does not rise to the height of the communication port 250, and the outflow of the liquid water from the communication port 250 is suppressed.

In the present embodiment, city gas containing desulfurized methane as a main component is used as the raw material gas. Also, the amount of water supplied to the evaporator 221 is set so that the amount of oxygen molecules that is three times the amount of carbon atoms in the average composition of the source gas is included.

In the present embodiment, since city gas containing methane as a main component is used as the raw material gas, the amount of water required for the presence of 3 moles of water vapor per 1 mole of methane to be supplied is 221. That is, the amount of water that makes the steam carbon ratio (S/C ratio) 3 is supplied to the evaporator 221 .

Since the hydrogen generator 200 has a multi-cylindrical structure, the reformer 222 also has a substantially donut shape (cylindrical shape with a hole in the center), and the raw material gas and water vapor are mixed from the entire upper surface of the reformer 222 . The mixed gas flows into reformer 222 .

The mixed gas of the raw material gas and steam that has flowed into the reformer 222 is heated to 600° C. by the heat of the heating unit 220 and reformed into a primary hydrogen-containing gas containing carbon monoxide by the reforming catalyst. At this time, a reaction to produce hydrogen and carbon dioxide from methane and water as shown in (Chem. 1) and a reaction to produce hydrogen and carbon monoxide from methane and water as shown in (Chem. 2) are taking place. .

However, 600.degree. For example, it can range from 400°C to 650°C.

The primary hydrogen-containing gas flows from reformer 222 into return channel 241 . The return channel 241 has a donut shape, and the primary hydrogen-containing gas flows upward in the axial direction along the entire circumference of the return channel 241 and is supplied to the CO reducer 223 . The CO reducer 223 also has a donut shape, and the primary hydrogen-containing gas flows into the CO reducer 223 from the entire circumference of the lower surface.

The CO reducer 223 reduces carbon monoxide contained in the primary hydrogen-containing gas and discharges it as a secondary hydrogen-containing gas. Specifically, the carbon monoxide and water vapor contained in the primary hydrogen-containing gas are reacted with each other to produce carbon dioxide and hydrogen by the transformation reaction shown in (Chemical 3) occurring in the carbon monoxide reduction catalyst, and the concentration of carbon monoxide is carbon monoxide is reduced to about 0.1 to 0.2%.

At this time, part of the heat generated by the shift reaction is transferred to the evaporator 221 via the outer cylinder 232, so that the CO reducer 223 is maintained at 250° C., which is suitable for chemical reaction.

However, 250° C. is a typical temperature, and the temperature inside the CO reducer 223 due to the reaction varies depending on the structure, material, and size of the CO reducer 223 . For example, it can vary from 200°C to 300°C.

The secondary hydrogen-containing gas discharged from the CO reducer 223 is discharged from the hydrogen-containing gas discharge pipe 236 to the outside of the hydrogen generator 200, and then supplied to a hydrogen utilization device such as a fuel cell power generator.

The combustion exhaust gas generated by the combustion of the burner of the heating unit 220 flows downward along the inner peripheral surface of the combustion tube 230, and then flows downward along the inner peripheral side of the combustion tube 230, and then reaches the bottom of the heating unit storage tube 233 and the combustion tube 230. After coming out to the outer peripheral side of the combustion cylinder 230 through the gap with the lower end, it is folded back upward and flows through the combustion exhaust gas flow path 240 between the combustion cylinder 230 and the heating unit storage cylinder 233. 222, and then heat-exchanged with the evaporator 221 when passing through the flue gas flow path 240 between the combustion cylinder 230 and the inner cylinder 231. It is discharged to the outside of the hydrogen generator 200 from the combustion exhaust gas outlet pipe.

[2-3. effect]
As described above, the hydrogen generator 200 according to the present embodiment includes the heating unit 220, the evaporating unit 221, the reformer 222, the combustion cylinder 230, the inner cylinder 231, the outer cylinder 232, and the heating unit housing. It has a cylinder 233 , a first partition 234 , a flue gas flow path 240 and a communication port 250 .

The heating unit 220 is configured to burn combustible gas and discharge flue gas. Combustion cylinder 230 has a central axis in the vertical direction and is configured to surround the outer circumference of heating section 220 . The inner cylinder 231 has a cylindrical shape with a central axis in the vertical direction, and is configured to surround the outer circumference of the combustion cylinder 230 . The outer cylinder 232 has a cylindrical shape having a central axis in the vertical direction, and is configured to surround the outer circumference of the inner cylinder 231 .

The heating unit housing cylinder 233 has a bottomed cylindrical shape with a vertical center axis, and is configured such that the upper end is joined to the lower end of the outer cylinder 232 and the combustion cylinder 230 is housed therein. The first partition wall 234 has a bottomed cylindrical shape with a central axis in the vertical direction, and is configured to accommodate the inner cylinder 231 , the outer cylinder 232 , and the heating unit housing cylinder 233 .

The combustion exhaust gas flow path 240 is formed between the combustion cylinder 230 and the cylinder composed of the inner cylinder 231 and the heating unit housing cylinder 233, and is configured to flow the combustion exhaust gas upward.

The evaporator 221 is formed between the inner cylinder 231 and the outer cylinder 232, heats the raw material gas and water with heat transmitted through the inner cylinder 231, evaporates the water, and converts the unevaporated liquid water into is configured to stay at the bottom.

The reformer 222 is formed by filling a reforming catalyst below the evaporator 221, and the heat transmitted through the heating unit storage cylinder 233 converts the mixed gas of the raw material gas and water vapor into monoxide through a reforming reaction. It is configured to produce a primary hydrogen-containing gas containing carbon.

A plurality of communication ports 250 are formed in the circumferential direction of the outer cylinder 232 at a position higher than the water level of the liquid water remaining in the lower portion of the evaporating section 221 without evaporating. It is configured to flow out to the reformer 222 .

A portion near the lower end of the inner cylinder 231 is formed with an annular recess that is recessed in the outer peripheral direction along the entire circumference of the inner peripheral surface, and an annular convex portion that protrudes in the outer peripheral direction is formed on the outer peripheral surface along the entire circumference. The cylinder wall of the cylinder 231 is bent in the outer peripheral direction over the entire circumference, and the protrusions on the outer peripheral surface of the inner cylinder 231 are curved on the inner peripheral surface of the outer cylinder 232 so that the unevaporated liquid water stays in the lower part of the evaporating part 221 . and adheres all around.

In the above configuration, the liquid water remaining in the lower part of the evaporating part 221 is distributed to the side wall part adjacent to the inner peripheral side of the liquid water parallel to the vertical direction in the inner cylinder 231, and to the liquid water inclined with respect to the vertical direction. By adopting a structure adjacent to the combustion exhaust gas flow path 240 via the convex portion adjacent to the lower side, compared to the conventional configuration in which an annular member having an L-shaped cross section is provided on the outer peripheral surface of the inner cylinder Since the heat transfer area from the high-temperature flue gas to the liquid water is larger than the liquid water retention amount, the evaporation of the liquid water is promoted more than before, and the total length (length in the vertical direction) of the evaporator 221 is increased. ) can be made shorter than before, the liquid water can be sufficiently evaporated.

As a result, deterioration of the reforming catalyst caused by liquid water entering the reformer 222 can be suppressed, and the overall length of the hydrogen generator 200 in the vertical direction can be shortened. If the overall length of the hydrogen generator 200 is shortened, the heat insulating material that covers the outer peripheral surface of the hydrogen generator 200 and the housing that houses the hydrogen generator 200 become smaller, so the material cost of the hydrogen generator 200 can be reduced.

In addition, in the present embodiment, hydrogen generator 200 may include CO reducer 223 , second partition 235 , hydrogen-containing gas discharge pipe 236 , and return channel 241 .

The CO reducer 223 is formed by filling a portion adjacent to the outer peripheral side of the evaporating section 221 with a carbon monoxide reducing catalyst between the first partition 234 and the outer cylinder 232 . It is configured to reduce the concentration of carbon monoxide contained in the hydrogen-containing gas through a chemical reaction and discharge it as a secondary hydrogen-containing gas.

The second partition wall 235 has a donut-shaped side portion having an inner diameter larger than the outer diameter of the outer cylinder 232 , an outer peripheral end connected to the upper end of the side portion, and an inner peripheral end joined to the outer peripheral surface of the outer cylinder 232 . The reformer 222 is formed by filling a reforming catalyst between the heating unit storage cylinder 233 and the second partition wall 235 .

The return flow path 241 is formed between the first partition 234 and the second partition 235, and configured to flow the primary hydrogen-containing gas that has flowed out of the reformer 222 upward (to the CO reducer 223). .

The hydrogen-containing gas discharge pipe 236 is provided in the first partition wall 234 and configured to discharge the secondary hydrogen-containing gas to the outside.

As a result, the reformer 222 can receive heat from the heating unit 220 uniformly in the circumferential direction, and the reforming reaction can be efficiently performed. Furthermore, the concentration of carbon monoxide contained in the primary hydrogen-containing gas generated in the reformer 222 can be reduced by a chemical reaction (transformation reaction) in the CO reducer 223 .

Therefore, when the hydrogen generator 200 supplies fuel gas to the fuel cell power generation device, the hydrogen-containing gas whose carbon monoxide concentration is reduced by the CO reducer 223 can be supplied to the fuel cell power generation device as the fuel gas. It is possible to suppress deterioration in the performance of the fuel cell power generation device due to carbon oxide.

In addition, without increasing the total length of the vertical direction of the hydrogen generator 200, the reforming catalyst of the reformer 222 is set to a temperature suitable for the reforming catalyst, and the carbon monoxide reduction catalyst of the CO reducer 223 is chemically reacted. It becomes possible to set the temperature suitable for (modification reaction).

Further, in the present embodiment, the hydrogen generator 200 may be configured by integrating the outer cylinder 232 and the heating unit storage cylinder 233 .

As a result, the liquid water remaining in the lower portion of the evaporating portion 221 passes through the portion where the convex portion of the outer peripheral surface of the inner cylinder 231 and the inner peripheral surface of the outer cylinder 232 are in close contact over the entire circumference, and flows out of the evaporating portion 221. However, the amount of liquid water that passes through the contact portion is small compared to the amount of liquid water that evaporates after staying in the lower portion of the evaporator 221, and the liquid water that passes through the contact portion is the combustion exhaust gas. It enters the channel 240 and evaporates.

Therefore, the liquid water remaining in the lower portion of the evaporating section 221 passes through the portion where the convex portion on the outer peripheral surface of the inner cylinder 231 and the inner peripheral surface of the outer cylinder 232 are in close contact over the entire circumference, and enters the reformer 222. can be suppressed. Therefore, deterioration of the reforming catalyst caused by liquid water entering the reformer 222 can be suppressed.

(Other embodiments)
As described above, Embodiment 1 and Embodiment 2 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to embodiments with modifications, replacements, additions, omissions, and the like. Also, it is possible to combine the components described in the first and second embodiments to form a new embodiment.

Therefore, another embodiment will be illustrated below with reference to FIG.

In Embodiments 1 and 2, a configuration including CO reducers 123 and 223 has been described as an example of means for reducing the concentration of carbon monoxide.

As shown in FIG. 3, the hydrogen generator 300 includes a CO remover 360, an air mixing cylinder 362, an air supply pipe 363, a partition member 364, and a second A first flow path 365, a second flow path 366, a header flow path 367, a second flow path inlet 368, a blowout hole 369, and a hydrogen-containing gas discharge pipe 336 may be provided.

The CO remover 360 is formed between the first partition 134 and the outer cylinder 132 and above the CO reducer 123 by filling a carbon monoxide removal catalyst, which contains secondary hydrogen flowing out of the CO reducer 123. It is configured to further reduce the concentration of carbon monoxide contained in the gas through a chemical reaction and discharge it as a tertiary hydrogen-containing gas.

The carbon monoxide removing catalyst packed in the CO remover 360 is a granular Ru-based catalyst with a diameter of 2 to 3 mm.

Immediately below the portion filled with the carbon monoxide reduction catalyst, a particle size smaller than that of the carbon monoxide removal catalyst that supports the carbon monoxide removal catalyst from below so that the filled carbon monoxide removal catalyst does not fall. A donut disk-shaped plate having a ventilation structure with a 1 mm diameter ventilation hole is disposed between the outer cylinder 132 and the first partition 134 .

Immediately above the portion filled with the carbon monoxide removal catalyst, even if the hydrogen generator 300 is turned upside down during manufacture (up and down in the direction of gravity when the hydrogen generator 300 is in use) In order to prevent the carbon monoxide removal catalyst from flowing out even if the carbon monoxide removal catalyst is turned upside down, the carbon monoxide removal catalyst is covered from above. A doughnut-shaped plate is arranged between the outer cylinder 132 and the first partition 134 .

The air mixing cylinder 362 is a metal member having a side portion, an upper surface portion, and a lower surface portion. It is configured to be divided into a second flow path 366, which is a side space, and an outer peripheral space.

The side portion of the air mixing cylinder 362 is cylindrical, has an inner diameter larger than the outer diameter of the outer cylinder 132 and an outer diameter smaller than the inner diameter of the first partition 134, and is arranged coaxially with the outer cylinder 132. It is configured to surround the tube 132 .

The upper surface of the air mixing cylinder 362 has an inclined doughnut-like shape, the outer peripheral end of which is connected to the upper end of the side surface, and the inner peripheral end of which is joined to the outer peripheral surface of the outer cylinder 132 . The lower surface of the air mixing cylinder 362 has a donut board shape, and is configured such that the outer peripheral end is connected to the lower end of the side surface and the inner peripheral end is joined to the outer peripheral surface of the outer cylinder 132 .

The partitioning member 364 is a doughnut-shaped metal member whose inner peripheral side end is joined to the side surface of the air mixing cylinder 362 and whose outer peripheral side end is joined to the first partition wall 134. It is configured to be divided into a header channel 367 that is an upper space and a first channel 365 that is an outer peripheral side lower space.

The air supply pipe 363 is provided vertically above the CO reducer 123 and below the CO remover 360 on the side surface of the first partition 134, and supplies air to the first flow path 365. is configured as

The secondary hydrogen-containing gas mixed with the air in the first flow path 365 is supplied from the second flow path inlet 368 at a position facing the tip of the air supply pipe 363 with the combustion tube 130 interposed in the side surface of the air mixing tube 362 . It is configured to flow into the second flow path 366 .

A plurality of blowout holes 369 are provided in the upper surface of the air mixing tube 362 in the circumferential direction, and are configured to allow the secondary hydrogen-containing gas mixed with the air in the second flow path 366 to flow out to the header flow path 367. .

The hydrogen-containing gas discharge pipe 336 is provided vertically above the CO remover 360 on the side surface of the first partition 134, and is configured to discharge the tertiary hydrogen-containing gas that has flowed out of the CO remover 360 to the outside. ing.

The secondary hydrogen-containing gas discharged from the CO reducer 123 flows into the first flow path 365 . The first flow path 365 has a doughnut-like shape, and the air injected through the air supply pipe 363 and the secondary hydrogen-containing gas are flowed and mixed in the circumferential direction of the first flow path 365 .

The secondary hydrogen-containing gas mixed with air enters second flow path 366 via second flow path inlet 368 .

The second flow path 366 also has a donut shape, and the secondary hydrogen-containing gas mixed with air flows in the circumferential direction of the second flow path 366 . After that, it is discharged from the second flow path 366 to the header flow path 367 through the blowing holes 369 .

Both the header channel 367 and the CO remover 360 have a donut shape, and the secondary hydrogen-containing gas mixed with air flows into the CO remover 360 from the entire periphery of the header channel 367 .

The CO remover 360 further reduces carbon monoxide contained in the secondary hydrogen-containing gas and discharges it as a tertiary hydrogen-containing gas. Specifically, the selective oxidation reaction shown in Chemical Formula 4 occurring in the carbon monoxide removal catalyst produces carbon dioxide from carbon monoxide and oxygen, and water is produced from hydrogen and oxygen as shown in Chemical Formula 5. The concentration of carbon is reduced to about several ppm.

At this time, part of the heat generated by the reactions shown in (Chem. 4) and (Chem. 5) is transferred to the evaporator 121 through the outer cylinder 132, and the CO remover 360 reaches a temperature suitable for the chemical reaction. is maintained at 150°C.

However, 150° C. is a typical temperature, and the temperature inside the CO remover 360 due to the reaction varies depending on the structure, material, and size of the CO remover 360 . For example, it can vary from 100°C to 180°C.

ＣＯ除去器３６０から排出された三次水素含有ガスは、水素含有ガス排出管３３６から水素生成装置３００の外部に排出された後に、燃料電池発電装置などの水素利用機器に供
給される。

The tertiary hydrogen-containing gas discharged from the CO remover 360 is discharged from the hydrogen-containing gas discharge pipe 336 to the outside of the hydrogen generator 300, and then supplied to a hydrogen utilization device such as a fuel cell power generator.

As a result, CO remover 360 can further reduce the concentration of carbon monoxide contained in the tertiary hydrogen-containing gas supplied from hydrogen generator 300 compared to hydrogen generator 100 of the first embodiment. Therefore, the deterioration of the performance of the fuel cell power generation device due to carbon monoxide can be suppressed, and the highly reliable hydrogen generation device 300 can be provided.

In Embodiments 1 and 2, as an example of means for suppressing liquid water from entering the reformers 122 and 222, the configuration including the evaporators 121 and 222 whose lower portions are closed has been described.

As shown in FIG. 3 , the hydrogen generator 300 may be provided with a water receiving tube 361 as an example of means for suppressing liquid water from entering the reformers 122 and 222 .

The water receiving cylinder 361 has an inner diameter larger than the outer diameter of the outer cylinder 132 and an outer diameter smaller than the inner diameter of the second partition wall 135 , and is arranged coaxially with the outer cylinder 132 to surround the outer cylinder 132 . The side surface portion and the outer peripheral end are connected to the lower end portion of the side surface portion, and the inner peripheral end closes the lower portion of the evaporating section 121 by closely contacting the convex portion on the outer peripheral surface of the inner cylinder 131 and the inner peripheral surface of the outer cylinder 132 over the entire surface. and a slanted doughnut-shaped lower surface portion that is airtightly joined to the portion where the metal member is formed.

The upper end of the side portion of the water receiving tube 361 is configured to be positioned vertically below the upper surface of the second partition 135 and above the communication port 150 in the vertical direction. There is a gap between the upper end of the water receiving cylinder 361 and the mixed gas of the raw material gas and water vapor.

Since the amount of raw material gas and the amount of water supplied to the evaporator 121 are larger than the amount of water evaporated in the evaporator 121, the water level of the liquid water remaining in the lower part of the evaporator 121 is lower than that of the communication port. 150 and the liquid water flows out from the communication port 150, the liquid water remains in the space surrounded by the side surface of the water receiving tube 361, the lower surface of the water receiving tube 361, and the side surface of the outer cylinder 132. Stay.

The mixed gas of the raw material gas and water vapor that has flowed out from the communication port 150 flows upward along the inner peripheral surface of the side surface of the water receiving tube 361, and then flows upward from the upper surface of the second partition wall 135 and the upper end of the water receiving tube 361. , and flows between the second partition wall 135 and the water receiving tube 361 to flow into the reformer 122 .

As a result, since the amount of raw material gas and the amount of water supplied to the evaporator 121 are larger than the amount of water evaporated in the evaporator 121 , liquid water flows out of the evaporator 121 from the communication port 150 . , the liquid water flowing out of the evaporating section 121 from the communication port 150 will enter the space surrounded by the side surface of the water receiving tube 361, the lower surface of the water receiving tube 361, and the side surface of the outer tube 132. Since the liquid water stays, the intrusion of the liquid water into the reformer 122 is suppressed. Therefore, deterioration of the reforming catalyst caused by intrusion of liquid water into the reformer 122 can be suppressed.

In addition, after the mixed gas of the raw material gas and water vapor flows out from the communication port 150 , the path to flow into the reformer 122 can be made longer than in the hydrogen generator 100 . Therefore, in the course of the mixed gas passing through the path, mixing due to concentration diffusion is promoted, and the raw material gas and water vapor are uniformly mixed and flow into the reformer 122, so that the reforming reaction can be efficiently carried out. can.

In addition, a process in which the convex portion of the outer peripheral surface of the inner cylinder 131 and the inner peripheral surface of the outer cylinder 132 are in close contact with each other over the entire surface to close the lower portion of the evaporating portion 121 and join airtightly; can be performed in the same manner as the process of airtightly joining the water receiving tube 361, the joining of the water receiving cylinder 361 can be easily performed, and the manufacturing cost can be reduced.

In Embodiments 1 and 2, the heating units 120, 220 and the combustion cylinders 130, 230 have cylindrical shapes. The shape of 130, 230 is not limited to cylindrical. However, if the heating units 120, 220 and the combustion cylinders 130, 230 are cylindrical in shape, the heat can be distributed evenly to the cylindrical reformers 122, 222 provided outside the circumference thereof.

Note that the above-described embodiment is for illustrating the technology in the present disclosure, and various changes, replacements, additions, omissions, etc. can be made within the scope of the claims or equivalents thereof.

The present disclosure is applicable to vessels in which only gas is supplied to the catalyst and liquid infiltration needs to be suppressed. Specifically, it can be applied to a hydrogen generator that generates a hydrogen-containing gas with a low carbon monoxide concentration, a fuel cell power generator that supplies hydrogen gas after removing impurities, a hydrogen refining system, and the like.

Reference Signs List 100,200,300 hydrogen generator 120,220 heating unit 121,221 evaporating unit 122,222 reformer 123,223 CO reducer 130,230 combustion tube 131,231 inner tube 132,232 outer tube 133,233 heating unit Storage tube 134, 234 First partition 135, 235 Second partition 136, 236, 336 Hydrogen-containing gas discharge pipe 140, 240 Flue gas channel 141, 241 Return channel 150, 250 Communication port 360 CO remover 361 Water receiver 362 Air mixing tube 363 Air supply pipe 365 First channel 366 Second channel 367 Header channel 368 Second channel inlet 369 Blowout hole

Claims (6)

a heating unit that burns combustible gas and discharges combustion exhaust gas;
a combustion cylinder having a central axis in the vertical direction and surrounding the outer periphery of the heating part;
an inner cylinder having a cylindrical shape with a center axis in a vertical direction and surrounding the outer periphery of the combustion cylinder;
an outer cylinder surrounding the outer circumference of the inner cylinder in a cylindrical shape having a central axis in the vertical direction;
a heating unit storage cylinder having a bottomed cylinder shape having a central axis in a vertical direction and containing the combustion cylinder, the upper end of which is joined to the lower end of the inner cylinder or the lower end of the outer cylinder;
a first partition having a bottomed cylindrical shape having a central axis in a vertical direction and accommodating the inner cylinder, the outer cylinder, and the heating unit housing cylinder;
a combustion exhaust gas flow path formed between a cylinder composed of the inner cylinder and the heating unit housing cylinder, and the combustion cylinder, for upwardly flowing the combustion exhaust gas;
Formed between the inner cylinder and the outer cylinder, the raw material gas and water are heated by the heat transmitted through the inner cylinder, the water is evaporated, and the unevaporated liquid water stays at the bottom. an evaporator configured to:
Formed by filling a reforming catalyst below the evaporator, the mixed gas of the raw material gas and water vapor is reformed by the heat transmitted through the heating unit storage cylinder to contain primary hydrogen containing carbon monoxide. a reformer that produces gas;
A plurality of vaporizers are formed in the circumferential direction of the outer cylinder at a position higher than the water level of the liquid water remaining without being evaporated in the lower part of the evaporator, and the source gas and the steam flow out from the evaporator to the reformer. a communication port for
A hydrogen generator having
In the portion near the lower end of the inner cylinder, an annular concave portion recessed in the outer peripheral direction is formed on the entire inner peripheral surface, and an annular convex portion protruding in the outer peripheral direction is formed on the outer peripheral surface along the entire peripheral surface. The cylindrical wall of the inner cylinder is bent in the outer peripheral direction over the entire circumference, and the convex portion on the outer peripheral surface of the inner cylinder is aligned with the inner circumference of the outer cylinder so that unevaporated liquid water stays in the lower part of the evaporating portion. A hydrogen generator characterized in that the surface and the entire circumference are in close contact with each other. On the inner peripheral surface and the outer peripheral surface of the inner cylinder, a convex portion and a recessed portion that are helical in the axial direction are integrally formed on the upper side of the communication port in the vertical direction. The convex portion of the outer peripheral surface is brought into close contact with the inner peripheral surface of the outer cylinder, and a spiral flow path for evaporating the water is formed between the inner cylinder and the outer cylinder. 2. The hydrogen generator according to 1. a side surface portion having an inner diameter larger than the outer diameter of the outer cylinder; and a doughnut-shaped upper surface portion having an outer peripheral end connected to an upper end portion of the side surface portion and an inner peripheral end joined to the outer peripheral surface of the outer cylinder. a second partition having
a return passage formed between the first partition and the second partition for upwardly flowing the primary hydrogen-containing gas that has flowed out of the reformer;
Between the first partition wall and the outer cylinder, a portion adjacent to the outer peripheral side of the evaporating section is filled with a carbon monoxide reducing catalyst, and is contained in the primary hydrogen-containing gas that has flowed out of the reformer. a CO reducer that reduces the concentration of carbon monoxide generated by a chemical reaction and discharges it as a secondary hydrogen-containing gas;
a hydrogen-containing gas discharge pipe provided in the first partition for discharging the secondary hydrogen-containing gas to the outside;
with
3. The hydrogen generator according to claim 1, wherein the reformer is formed between the heating unit housing tube and the second partition. A portion where the convex portion on the outer peripheral surface of the inner cylinder is in close contact with the inner peripheral surface of the outer cylinder over the entire circumference is airtightly joined so that the unevaporated liquid water stays in the lower portion of the evaporating portion. The hydrogen generator according to any one of claims 1 to 3, characterized in that 5. The hydrogen generator according to claim 4, wherein the heating unit housing cylinder and the inner cylinder are integrally formed. 5. The hydrogen generator according to any one of claims 1 to 4, wherein the heating unit housing cylinder and the outer cylinder are integrally formed.

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