JP2003306308A - Steam reforming and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus with a simple structure and a small size capable of producing a reformed gas which contains a reduced amount of carbon monoxide and is rich in hydrogen. <P>SOLUTION: A gas introducing part 22 always supplies a methane gas from a channel end 22a and steam from a channel end 22b. Thereby, a reforming device 24 is divided into a methane-introducing part 24at0 into which a methane gas is introduced and a steam-introducing part 24bt0 into which steam is introduced. At the methane-introducing part 24at0, a hydrogen gas and carbon are produced in the presence of a reforming catalyst by supplying only methane, and the carbon is adsorbed to the reforming catalyst. Almost no carbon monoxide is produced at this time. Then, the reforming device 24 is rotated, and steam is now introduced into the methane-introducing part 24at0. Thus, when steam is introduced, the adsorbed carbon reacts with the steam by the reforming catalyst to cause the desorption of carbon and regeneration of the catalyst. This is repeated with the rotation of the reforming device. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a reformer and a reforming method for producing a hydrogen-rich reformed gas by subjecting a hydrocarbon-based compound to steam reforming, and a fuel for generating electricity using this reformed gas. Regarding battery system.

[0002]

2. Description of the Related Art When a hydrocarbon compound is subjected to steam reforming through a reforming catalyst, a hydrogen-rich reformed gas containing hydrogen, carbon dioxide and water (steam) can be produced. This hydrogen-rich reformed gas is used as a fuel gas for a fuel cell that is supplied with a hydrogen-rich fuel gas and an oxygen-containing gas to generate electricity.

[0003]

However, in the conventional reformer, the following problems remain unsolved.

[0004] In the steam reforming reaction process, multistage reactions proceed in parallel by the reforming catalyst based on the mixed supply of steam and raw fuel gas. Since the reaction in each stage progresses in a complicated manner due to the presence of steam and raw fuel gas, carbon monoxide as a reaction intermediate product is contained in the reformed gas after the reforming reaction. The carbon monoxide is contained at a rate of several% to several tens of%, and the content thereof depends on various conditions such as the temperature condition during the reforming reaction and the supply condition of the raw fuel gas.

Since carbon monoxide is a poisonous substance that causes deterioration of catalyst performance in the fuel cell, it is necessary to incorporate a carbon monoxide reducing device (CO reducing device) downstream of the reforming device. For this reason, a CO reduction device is required, which leads to a complicated structure and an increase in size of the device. Moreover, control for increasing the CO reduction efficiency by the CO reduction device was also necessary.

The present invention has been made to solve the above-mentioned problems, and provides a reformer capable of producing a hydrogen-rich reformed gas in which the content of carbon monoxide is suppressed. The purpose is to eliminate the CO reduction device, simplify the structure, and downsize the device.

[0007]

Means for Solving the Problem and Its Action / Effect To solve at least a part of the problem, the first reformer of the present invention is a hydrogen-rich reformer through steam reforming of a hydrocarbon compound. A reformer for producing a high quality gas, the reformer having a reforming catalyst used for steam reforming, and an introduction part for introducing a raw material gas and steam into the reformer, Rotate relative to the flow direction.

In this case, in addition to rotating both the introduction section and the reformer in opposite directions, one of the introduction section and the reformer may be rotated. When rotating the introduction part, it is necessary to take measures for airtightness associated with rotation in the gas introduction mechanism, while rotating the reformer simplifies such measures for airtightness.
preferable. Also, the mechanism for rotating the reformer is
A rotation transmission mechanism or the like is sufficient, and the configuration is simple.

As described above, in the reforming apparatus of the present invention in which the introduction section and the reformer are relatively rotated, the introduction section has the first part.
Raw fuel gas containing a hydrocarbon compound is introduced into the reformer from the flow path, and steam is introduced into the reformer from the second flow path. As a result, the reformer is divided into a raw fuel gas introduction part that receives the raw fuel gas and a steam introduction part that receives the steam.

In the portion where the raw fuel gas is introduced, the reforming catalyst causes a reforming reaction under the condition that almost no steam exists, and causes a decomposition reaction of the hydrocarbon compound represented by the following formula.

2CnHm → 2nC + mH ₂ ...

Due to the progress of this equation, the raw fuel gas introduction portion of the reformer produces hydrogen gas and hardly produces carbon monoxide. Further, the generated carbon is adsorbed on the reforming catalyst. In this case, in order to make the equation proceed almost completely to the introduced raw fuel gas, the reformer temperature and other conditions on the reformer side, the amount of introduced raw fuel gas, and the mixture of steam are mixed. Should be suppressed. In this way, carbon monoxide production can be avoided more reliably.

The raw fuel gas introduction portion in which the hydrogen gas is generated and the carbon is adsorbed as described above is newly introduced with the steam due to the relative rotation. This water vapor is exposed to the reforming catalyst in a state where the raw fuel gas is scarcely present, so that the reforming catalyst reacts with the adsorbed carbon.
This reaction is represented by the following formula.

C + 2H ₂ O → CO ₂ + 2H ₂ ...

Hydrogen gas and carbon dioxide gas are produced by the progress of this equation, and these gases merge with the hydrogen gas produced by the above equation and flow downstream of the reformer. Then, due to the generation of carbon dioxide, the carbon adsorbed on the reforming catalyst is taken from the catalyst surface, and the catalyst surface is regenerated. As a result, when the raw fuel gas is newly introduced due to the above relative rotation, the reforming catalyst already regenerated
The above formula can be favorably progressed and the catalytic reaction efficiency can be maintained high. Even in this case, in order for the formula to proceed almost completely, the conditions such as the reformer temperature should be adjusted,
It is sufficient to suppress the mixture of raw fuel gas. This can ensure the regeneration of the catalyst surface of the reforming catalyst.

Such gas generation, that is, hydrogen gas generation in the raw fuel gas introduction portion and subsequent hydrogen gas / carbon dioxide gas generation by steam introduction is accompanied by relative rotation of the introduction portion and the reformer. These gases (reformed gas) merge and flow downstream of the reformer.
As a result, the reformed gas (combined gas) obtained from the reformer is not only rich in hydrogen but also stable in hydrogen concentration, and contains almost no carbon monoxide. In other words, according to the reforming apparatus of the present invention, a hydrogen-rich gas having an extremely low carbon monoxide content can be continuously produced at a stable hydrogen concentration. In addition, the regeneration of the reforming catalyst enables stable progress of the reaction and maintenance of the reaction efficiency, which also improves the hydrogen-rich gas production efficiency. Therefore, even when the generated hydrogen-rich gas is supplied to another device (for example, a fuel cell), it is not necessary to install a device for reducing carbon monoxide downstream of the reforming device. It is possible to simplify and downsize the device. In particular, in a vehicle using a fuel cell as a drive source, size restrictions on mounting a system including a reformer / fuel cell can be reduced, so that the degree of freedom of application to the vehicle can be increased.

Further, since it is not necessary to install a device for reducing carbon monoxide, starting control and drive control of these devices are unnecessary. Therefore, it is possible to improve the startability of the reformer and the system that uses the reformed gas (for example, the fuel cell system, the vehicle, etc.) and simplify the control.

Such hydrogen-rich reformed gas is produced by introducing the raw fuel gas containing the hydrocarbon compound and steam into a reformer having a reforming catalyst used for the steam reforming. Introducing the raw fuel gas into the reformer and introducing the steam into the reformer, introducing the steam into the introducing place where the raw fuel gas was introduced, and introducing the steam into the introducing place. It can be achieved by a method of repeating the steps of introducing the raw fuel gas into the.

The first reforming apparatus of the present invention having the above construction can also take the following modes. That is, when introducing water vapor from the second flow path, the oxygen-containing gas can be introduced together with the water vapor. By doing so, the oxidation reaction of the carbon adsorbed on the catalyst surface by the following formula can be caused by oxygen itself to generate heat. Therefore, it is possible to improve the regeneration efficiency of the catalyst surface and to provide heat to the reformer temperature rise / endothermic reaction (formula) by heat, which contributes to the improvement of the reforming efficiency.

C + O ₂ → CO ₂ ...

In this case, the second flow path may be configured to guide the cathode off gas of the fuel cell which is supplied with the hydrogen-rich reformed gas as the fuel gas to generate electric power. Since this cathode off gas contains water (steam) and oxygen which are power generation reaction products, a device for introducing an oxygen-containing gas is not required, and the device can be simplified.

Further, the introduction part has an oxygen introduction flow path for introducing the oxygen-containing gas, and the end of the oxygen introduction flow path is located between the end of the first flow path and the end of the second flow path. It is also possible to intervene. By doing this, it is possible to repeatedly cause new introduction of the oxygen-containing gas into the raw fuel gas introduction section and new introduction of the oxygen-containing gas into the steam introduction section with the relative rotation of the introduction section and the reformer. You can Therefore, it is possible to further advance the reforming efficiency by promoting the above equations in both the introducing portions and making sure the regeneration of the catalyst surface, the temperature rise of the reformer, and the heat donation, and the reforming efficiency.

Further, a second reforming apparatus of the present invention for achieving at least a part of the above-mentioned problems is a reforming apparatus for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound. Accordingly, the first and second reformers having the reforming catalyst used for the steam reforming, and the raw fuel gas containing the hydrocarbon compound and the steam are alternately introduced to the first reformer. A first introduction part and a second introduction part for alternately introducing the raw fuel gas and steam to the second reformer, and the reformed gas from the first and second reformers are combined. And a downstream flow path that guides the water vapor to the downstream side, and one of the first introduction section and the second introduction section guides the water vapor while the other guides the raw fuel gas.

Even in the reformer having this structure, the raw fuel gas and the steam are alternately introduced in the first and second reformers, respectively, and the above equations and equations are repeated. Then, on the downstream side of the reformer, the produced gas according to the formula in one reformer and the produced gas according to the formula in the other reformer join and are guided to the downstream side. As a result, similar to the above-described first reforming apparatus of the present invention, it is possible to produce an effect such that a hydrogen-rich gas having an extremely low carbon monoxide content can be continuously produced at a stable hydrogen concentration.

In this case, the first and second reformers may be separate bodies, and one reformer may be divided into the first and second reformers.

Further, a third reforming apparatus of the present invention for achieving at least a part of the above problems is a reforming apparatus for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound. Therefore, the reformer includes a reforming catalyst used for steam reforming and an adsorbent having a carbon dioxide adsorption function,
The reformer and the introduction part for guiding the gas to the reformer are relatively rotated around the flow direction of the gas in the reformer. Moreover, the introduction of gas from the introduction section guides the raw fuel gas containing the hydrocarbon compound and the water vapor from the first flow path of the introduction section, and the carbon dioxide release from the adsorbent from the second flow path. Guide possible purge gases.

In the reformer having such a structure, the reformer is divided into a raw fuel / steam introduction part for receiving the raw fuel gas and steam and a purge gas introduction part for introducing the purge gas.

In this raw fuel / steam introducing portion, the reforming catalyst causes a reforming reaction in the coexistence of the raw fuel / steam, so that the reforming reaction of the hydrocarbon compound represented by the following formula cause. For convenience of explanation, the raw fuel gas is assumed to be methane.

CH ₄ + H ₂ O → CO + 3H ₂ ... CO + H ₂ O → CO ₂ + H ₂ ... CO ₂ + H ₂ → CO + H ₂ O ...

This equation is commonly referred to as the shift reaction,
The equation is called the reverse shift reaction, where the opposite reaction occurs. Then, the reaction of · proceeds according to the production status of carbon monoxide, the supply status of water vapor, the production status of carbon dioxide, etc., and the reaction rate is restricted by the restriction of equilibrium.

By the progress of these equations, hydrogen, carbon dioxide, and carbon monoxide are produced in the raw fuel / steam introduction portion of the reformer. This carbon dioxide is adsorbed by the adsorbent of the reformer and taken out to the solid phase outside the system (outside the reforming catalytic reaction system). Therefore, due to the equilibrium relationship, the shift reaction of the formula proceeds at a rate-determining rate and suppresses the progress of the reverse shift reaction of the formula. As a result, the raw fuel / steam introducing portion of the reformer generates hydrogen gas and carbon dioxide, and hardly generates carbon monoxide.

The raw fuel / water vapor introduction portion in which hydrogen gas / carbon dioxide is produced and carbon dioxide is adsorbed is newly introduced with the purge gas due to the relative rotation. Since the purge gas is exposed to the adsorbent that has adsorbed carbon dioxide, the carbon dioxide adsorbed by the adsorbent is released (released) from the adsorbent, and the carbon dioxide adsorbing function of the adsorbent is regenerated. Therefore, carbon dioxide gas is generated from the raw fuel / steam introducing portion to which the purge gas is newly introduced due to the relative rotation. On this occasion,
Since the purge gas only acts on the adsorbent and does not participate in the reforming reaction in the reforming catalyst, carbon monoxide is hardly produced. The surplus purge gas flows downstream of the reformer together with the carbon dioxide generated by the regeneration of the carbon dioxide adsorption function.

When introducing the purge gas, the gas conditions may be determined in consideration of the adsorption function of the carbon dioxide adsorbent. In other words, if the adsorbent has a carbon dioxide adsorption function in a low temperature environment, introducing a high temperature purge gas,
Carbon dioxide can be released from the adsorbent. On the contrary, if the adsorbent has a carbon dioxide adsorption function in a high temperature environment, a low temperature purge gas can be introduced to release carbon dioxide.

Such gas generation, that is, generation of hydrogen / carbon dioxide in the raw fuel / steam introduction portion and subsequent generation / release of carbon dioxide by introduction of the purge gas is caused by relative rotation of the introduction portion and the reformer. Accordingly, the carbon monoxide can be made to be scarcely contained when hydrogen and carbon dioxide are produced in the raw fuel / water vapor introduction part. As a result, the reformed gas (produced gas in the raw fuel / steam introduction part) obtained from the reformer is not only rich in hydrogen, but also stable in hydrogen concentration and contains almost no carbon monoxide. It will not be included. Therefore, this reforming apparatus of the present invention also has the effect of continuously producing a hydrogen-rich gas having an extremely low carbon monoxide content at a stable hydrogen concentration, like the first reforming apparatus of the present invention. be able to.

Further, a fourth reforming apparatus of the present invention for achieving at least a part of the above problems is a reforming apparatus for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound. There is a reforming catalyst used for the steam reforming,
First and second reformers having an adsorbent having an adsorption function of carbon dioxide, a mixed gas of a raw fuel gas containing a hydrocarbon compound and steam, and carbon dioxide in the first reformer. First introducing section for alternately introducing a purge gas capable of causing carbon dioxide release from the adsorbent having adsorbed carbon dioxide, and a second introducing section for alternately introducing the mixed gas and the purge gas to the second reformer. The first introduction part and the second introduction part are characterized in that, while one guides the mixed gas, the other guides the purge gas.

Even in the reformer having this structure, the mixed gas of the raw fuel gas and the steam and the purge gas are alternately introduced into each of the first and second reformers, and the reaction of the above formula Repeat the adsorbent regeneration. Then, the gas (hydrogen gas and carbon dioxide gas) generated by the equation in one reformer and the carbon dioxide gas in the other reformer can be introduced downstream of the reformer. As a result, similar to the above-described third reforming apparatus of the present invention, it is possible to produce an effect such that a hydrogen-rich gas having an extremely low carbon monoxide content can be continuously produced at a stable hydrogen concentration.

The first and second reformers may be provided separately or separately, and one reformer may be divided into the first and second reformers.

Further, in the third and fourth reforming devices described above, the purge gas introduced may be the anode off gas of the fuel cell. This anode off gas is a gas after hydrogen consumption in the power generation reaction, but since it contains unreacted hydrogen, it can be easily heated to a predetermined temperature through this hydrogen oxidation reaction (combustion). Therefore, since it can be used as a purge gas for releasing carbon dioxide, a device for introducing the purge gas is not required, and the device can be simplified.

Such a reforming apparatus can be applied as a component using the reformed gas, for example, a fuel cell system, or a component of a vehicle equipped with the fuel cell system.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a reformer according to the present invention will be described based on an example of a fuel cell system having this reformer. FIG. 1 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of the present embodiment, FIG. 2 is an explanatory diagram illustrating a schematic configuration of a reformer 20 included in the fuel cell system 10, and FIG. 3-3 in FIG.
It is explanatory drawing which shows the schematic structure cross-sectioned along the line.

The fuel cell system 10 produces a hydrogen-rich reformed gas by a methane gas supply device 12 for supplying stored methane gas, a steam supply device 14 for supplying stored water as steam, and a reforming reaction of methane. The reformer 20 includes a fuel cell 40 that obtains electromotive force by an electrochemical reaction, and a blower 42 that compresses air and supplies the compressed air to the fuel cell 40.

The methane gas supply device 12 is provided with a valve (not shown) in the flow path 13, and the valve opening is adjusted based on a control signal from an electronic control device (not shown) to adjust the amount of methane gas supplied to the reformer 20. To do. The methane gas supply device 12 can be configured to store and supply purified methane gas, or can also be configured to store natural gas and remove the sulfur content from the natural gas to supply purified methane gas. it can.

The steam supply unit 14 sends the stored water to a heating / evaporating section (not shown) to convert it into steam,
This steam is supplied to the reformer 20 through the flow path 15.
In this steam supply device 14, a water pump (not shown) for supplying water to the heating / evaporating section and a valve (not shown) provided in the flow path 15 are drive-controlled based on a control signal from the electronic control device. Then, the amount of steam supplied to the reformer 20 is adjusted.

The heating of the steam supply device 14
The evaporator is equipped with a combustion catalyst, and the heat required for vaporizing water is generated by the combustion reaction. As the fuel used for this combustion reaction, methane gas stored in the methane gas supply device 12 and anode off gas discharged from the anode side of the fuel cell 40 are used.

As shown in FIG. 2, the reforming device 20 has a gas introducing portion 22 for receiving gas and a reformer 24 for causing a reforming reaction. The gas introduction part 22 is provided with upper and lower flow path end parts 22a and 22b partitioned by a partition wall 23, and the flow path 13 and the flow path 15 described above are provided at the respective flow path end parts.
Are in communication. That is, the gas introduction unit 22 connects the flow path end portion 22 a, which is the end of the methane flow path 13, and the flow path end portion 22 b, which is the end of the steam flow path 15, to the reformer 2.
Reformer 2 by separating methane and water vapor from each other.
Introduce to 4. In this case, the ends of the flow paths 13 and 15 are expanded to form the ends of the flow paths themselves.
It can also be 2a, 22b.

The reformer 24 is formed by forming a gas flow path in a so-called honeycomb shape. Therefore, the channel end 2
Methane from 2a passes through the honeycomb-shaped gas flow passage in the portion facing the flow passage end 22a, and reaches the downstream side of the reformer. Water vapor from the flow path end portion 22b passes through the honeycomb-shaped gas flow path in a portion facing the flow path end portion 22b,
Downstream of the reformer. That is, the reformer 24 is divided into a methane introduction part that receives the introduction of methane gas and a steam introduction part that receives the introduction of steam. Then, downstream of the reformer 24, the gas that has passed through the honeycomb-shaped gas flow passage in the portion facing the flow passage end 22a and the gas that has passed through the honeycomb-shaped gas flow passage in the portion facing the flow passage end 22b. And are combined and supplied to the fuel cell 40 downstream of the reformer.

In the honeycomb-shaped gas passage (methane introduction portion) of the reformer 24 facing the passage end 22a, methane gas passes through the honeycomb-shaped gas passage under the condition that water vapor is scarcely present. Therefore, the reformer 24
Is a reforming catalyst (for example, rhodium (Rh), which can cause a decomposition reaction represented by the following formula (1) when passing through this gas,
Ruthenium (Ru), Nickel (Ni), Platinum (P
t), palladium (Pd), cobalt (Co), and reforming catalysts such as alloys of these) are supported on each of the honeycomb-shaped gas flow paths.

CH ₄ → C + 2H ₂ (1)

On the other hand, water vapor passes through the honeycomb-shaped gas flow passage (methane introduction portion) in the portion facing the flow passage end portion 22b. In this example, the carbon deposited and adsorbed on the catalyst surface in the above formula (1) is caused to separate from the catalyst surface by this water vapor so as to cause a reaction represented by the following formula (2).

C + 2H ₂ O → CO ₂ + 2H ₂ (2)

Therefore, even in the honeycomb-shaped gas flow passage (water vapor introduction portion) in the portion facing the flow passage end portion 22b,
The same reforming catalyst as that in the honeycomb-shaped gas flow passage (methane introduction portion) in the portion facing the flow passage end portion 22a was supported. That is, the reformer 24 carries the above-mentioned reforming catalyst in each of the honeycomb-shaped gas passages thereof.

The reformer 20 includes the above-mentioned gas introduction section 22.
And the reformer 24 are airtightly connected to each other, and a drive device 26 that rotationally drives the reformer 24 is provided. The drive device 26 includes a motor (not shown) that rotates in response to a signal from the electronic control device, and a transmission mechanism (not shown) that transmits the motor rotation to the reformer 24. The reformer 24 is driven to rotate around the flow direction. As a result, the reformer 24 and the methane / steam gas introduction section 22 that cause the reactions of the above equations (1) and (2) rotate relatively around the gas flow direction in the reformer 24. Then, the steam is newly introduced into the methane introduction portion of the reformer 24, which has been receiving the introduction of methane gas until then. Methane gas is newly introduced into the steam introduction portion of the reformer 24, which has been receiving the introduction of steam until then. And to the fuel cell 40,
A mixed gas (reformed gas) obtained by mixing gases from the methane introduction part and the steam introduction part is supplied, and the fuel cell 40 causes an electrochemical reaction between hydrogen in this gas and oxygen in the air from the blower 42. ,Generate electricity.

Next, the properties of the reformed gas provided by the reformer 20 of the fuel cell system 10 having the above-mentioned structure will be described. FIG. 4 is an explanatory diagram for explaining the rotation operation of the reformer 24 of the reformer 20 and the reaction states of the equations (1) and (2) in association with each other.

The gas introducing portion 22 has a flow path end portion 22a.
To constantly supply the methane gas to the reformer 24, and constantly supply the steam to the reformer 24 from the flow path end portion 22b. Now, in parallel with such gas supply, the reformer 2 is driven by the drive unit 26.
Assume a certain time t0 when 4 is rotated. At this time t0, the reformer 24 has the partition wall 23 of the gas introduction unit 22.
Upper and lower introduction portions centering on a portion facing each other, that is, a methane introduction portion 24a for receiving methane gas from the flow path end portion 22a and a steam introduction portion 24b for receiving steam.
Divided into In addition, the part which divides the reformer 24 into such upper and lower introduction parts is made into a division line for convenience, and is shown like division lines 25t0 to 25t4 in correspondence with each time. The division line 25t0 at the time t0 is indicated by a thick line in the figure. Further, regarding the methane introduction part 24a and the steam introduction part 24b at each time,
In addition to the correspondence with the time, the solid line represents the introduction of methane and the wavy line represents the introduction of steam, and the solid line at time t0
The wavy line is left drawn.

At this time t0, the methane introduction portion 24a
In, the reaction of the above-mentioned formula (1) proceeds. As a result, the reformer 24 produces hydrogen gas and carbon from methane, causes hydrogen to flow downstream of the reformer, and adsorbs carbon to the reforming catalyst. As can be seen from the equation (1), carbon monoxide is scarcely generated during such hydrogen generation.

In this embodiment, since the supply amount of methane is adjusted based on the control signal from the electronic control unit, the formula (1) is made to proceed almost completely. Therefore, it is possible to surely generate the hydrogen gas and also to surely avoid the generation of carbon monoxide.

The methane introduction portion 24at0 in which hydrogen gas is generated and carbon is adsorbed in this manner gradually overlaps the flow passage end portion 22b of the gas introduction portion 22 as the reformer 24 itself rotates, and receives the introduction of water vapor. That is, the steam transition portion 26a where the methane introduction portion 24at0 overlaps the flow path end portion 22b and newly receives the introduction of steam gradually increases as shown in FIG. 4, and at the time t4, the methane introduction portion 24a.
All of t0 becomes the steam transition portion 26a. In the steam transition portion 26a, the steam is exposed to the reforming catalyst in a state where carbon is adsorbed on the catalyst surface by the introduction of methane up to that point. Therefore, this water vapor transition portion 26a
In the above, the reforming catalyst causes the adsorbed carbon and water vapor to cause the reaction of the above-described formula (2) to generate carbon dioxide and hydrogen, and to desorb carbon from the catalyst surface and regenerate the catalyst. And the hydrogen and carbon dioxide thus generated are
It flows downstream of the reformer, merges with the hydrogen generated in the methane introduction part 24a, and is supplied to the fuel cell 40. Even in the case of the reaction in the water vapor transition portion 26a, (2)
As can be seen, it produces almost no carbon monoxide.

On the other hand, the steam introducing portion 24bt0, which has been receiving the steam from the time t0, is
With the rotation of 4 itself, it gradually overlaps the flow path end 22a of the gas introduction part 22 and receives the introduction of methane. That is, the steam introduction portion 24bt0 overlaps the flow path end portion 22a, and the methane transition portion 26b newly receiving introduction of methane is
As shown in FIG. 4, it gradually increases, and at time t4, the entire steam introduction portion 24bt0 becomes the methane transition portion 26b. In the methane transition portion 26b, methane is exposed to the reforming catalyst in a state where carbon has been desorbed from the catalyst surface and catalyst has been regenerated by the introduction of water vapor until then. Therefore,
In the methane transition portion 26b, the regenerated reforming catalyst causes the reaction of the above-described equation (1) to generate hydrogen and adsorb carbon on the catalyst surface. Then, the hydrogen thus generated is used for the fuel cell 40 downstream of the reformer as described above.
Is supplied to.

As described above, in this embodiment, the hydrogen gas generation in the methane introduction part 24a and the methane transition part 26b,
The generation of hydrogen gas / carbon dioxide gas by the introduction of water vapor in the water vapor introduction portion 24b and the water vapor transition portion 26a is repeatedly and simultaneously advanced with the rotation of the reformer 24. Then, these gases (reforming gas) are combined downstream of the reformer 24 and supplied to the fuel cell 40. These gas generations are
Since it is based on the above formulas (1) and (2), it hardly generates carbon monoxide in the reaction process.
As a result, the reformed gas (the above confluent gas) supplied from the reformer 20 to the fuel cell 40 is not only rich in hydrogen but also stable in hydrogen concentration, and contains almost no carbon monoxide. Will be things. Therefore, according to the reforming apparatus 20 of the present embodiment, it is possible to continuously generate a hydrogen-rich gas having an extremely low carbon monoxide content at a stable hydrogen concentration and supply it to the fuel cell 40. In addition, the regeneration of the reforming catalyst enables stable progress of the reaction and maintenance of the reaction efficiency, which also improves the hydrogen-rich gas production efficiency. Therefore, between the reformer 20 and the fuel cell 40,
Since it is not necessary to install a device for reducing carbon monoxide, the structure can be simplified and the device can be downsized.
Therefore, the fuel cell system 10 of the present embodiment can be easily mounted even in a vehicle that is restricted in size by mounting the device, and the flexibility of applying the fuel cell system 10 to the vehicle can be increased. Specifically, the fuel cell system 10 can be mounted on a small vehicle.

Further, since it is not necessary to install a device for reducing carbon monoxide, starting control and drive control of these devices are unnecessary. Therefore, it is possible to improve the startability of the fuel cell system 10 as a whole and to simplify the control.

Further, in this embodiment, the reformer 24 was rotated and the gas introduction part 22 was fixed.
Therefore, when rotating the gas introduction part 22, methane
In contrast to the need for airtight measures when ventilating steam, this embodiment does not require such airtight measures, and the structure can be simplified accordingly. Further, for the rotation of the reformer 24, it suffices to prepare a motor as a drive source and a rotation transmission device such as a belt and a gear, so that a simple and inexpensive structure is required.
preferable.

It is also possible to rotate only the gas introduction part 22 or to rotate both the gas introduction part 22 and the reformer 24 forward and backward after taking measures against airtightness when venting methane and water vapor. it can.

Further, when the reformer 24 is rotated, the reformer 24 is constantly rotated at a predetermined rotation speed, and intermittent rotation is performed so that the reformer 24 is half-rotated for a predetermined time. You can also do it. More specifically, the reformer 24 is stopped for a predetermined time in the state of time t0 in FIG. 4, and then quickly reversed to the state of time t4.
After a lapse of a predetermined time in the state of time t4 after this inversion, the state is promptly inverted to the state of time t0 and this is repeated. In this way, the methane introduction part 24a receives steam next to methane in almost all areas thereof, and the steam introduction part 24b receives steam followed by methane in all cheek areas thereof. .

Here, a modification of the above embodiment will be described. FIG. 5 is an explanatory diagram showing a schematic configuration of the fuel cell system 10 of the modified example. As shown in the figure, in this modification, the raw fuel gas is a hydrocarbon-based compound represented by CnHm and having a carbon number of more than 6 to 7 (for example, benzene), and the methane gas supply Device 12
Instead of the above, a supply device 50 is provided, and a pre-reformer 51 is provided in the flow path 13 reaching the gas introduction part 22. This pre-reformer 51
A cracking catalyst (for example, zeolite, amorphous silica alumina, etc.) is filled in each. By doing so, after the heavy hydrocarbon compound such as benzene having a large number of carbon atoms is made to have a small number of carbon atoms by the above catalyst,
It can be supplied to the reformer 24 via the gas introduction part 22. As described above, the reforming reaction (formula (1)) of the hydrocarbon compound having a small number of carbons and the reaction of hydrogen / carbon dioxide production and catalyst regeneration (formula (2)) are modified. The hydrogen-rich reformed gas is generated in the same manner as in the above-described embodiment by performing the parallel operation in accordance with the rotation of the quality control device 24. Further, the carbon monoxide content in the reformed gas can be made extremely low.

In this modification, the range of application of hydrocarbon compounds used for reforming can be expanded to heavy ones, so that the degree of freedom in fuel selection is increased and the spread and application of the fuel cell system 10 is promoted. Can be promoted.

In addition to the provision of the pre-reformer 51 in the flow path 13 as described above, the following can be carried out. That is, in the gas introduction part 22, the flow channel end 22a into which the hydrocarbon compound flows can be a honeycomb gas flow channel, and the above catalyst such as zeolite can be carried in the flow channel. Further, the upstream side portion of the reformer 24 may be a catalyst supporting portion such as zeolite and the downstream thereof may be a reforming catalyst supporting portion. In this way, even in the catalyst supporting portion such as the zeolite or the like, steam is introduced as the reformer 24 rotates, so that the catalyst can be regenerated by the steam. Therefore, through the regeneration of the catalyst function that reduces the number of carbon atoms in heavy hydrocarbon compounds,
It is possible to bring about stabilization of the property of the reformed gas.

Further, it can be modified as follows.
FIG. 6 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of another modification. As shown in the figure, this modification includes a cathode-side exhaust passage 44 of the fuel cell 40 connected to the passage 15 via a valve 45. This way
When introducing the steam from the steam supply device 14, the steam and the cathode off gas can be mixed and introduced into the reformer 24. Since the cathode off-gas contains water (steam) as a power generation reaction product in the fuel cell 40 and oxygen, it is possible to introduce oxygen together with steam into the steam introducing portion 24b of the reformer 24. Therefore, when the methane introduction part 24a newly receives the introduction of steam due to the rotation of the reformer 24, it also receives the introduction of oxygen in addition to the steam. Therefore, the carbon adsorbed on the catalyst surface can be oxidized by oxygen as shown in the following formula (3) to generate heat. As a result, the efficiency of regeneration of the catalyst surface can be improved, and heat can be provided to the reformer temperature rise / endothermic reaction (equation (1)) by heat, which contributes to improvement of the reforming efficiency.

C + O ₂ → CO ₂ (3)

The valve 45 is controlled to be opened / closed by an electronic control unit to introduce / stop the cathode off gas. For example, when the temperature of the reformer 24 has not risen sufficiently just after the start-up, if cathode offgas is introduced to cause the exothermic reaction of the above formula (3), the temperature of the reformer rises,
This is preferable because it can activate the reforming reaction. In addition,
Since the production of carbon monoxide can be suppressed also by the formula (3), a reformed gas having an extremely low carbon monoxide content can be supplied to the downstream of the reformer 20, as in the above-described embodiment.
It is possible to achieve the effect of downsizing the device. The cathode offgas may be introduced in part or in total depending on the operating conditions.

Instead of introducing the cathode off gas, an oxygen-containing gas (for example, air) may be introduced. For example, a blower may be separately provided, and the flow path from this blower may be connected to the valve 45. When the cathode off gas is introduced as described above, such a blower is not required, which is advantageous in terms of downsizing of the device and simplification of the configuration.

Further, it can be modified as follows.
FIG. 7 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of another modified example, and FIG. 8 is an explanatory diagram for explaining how gas is introduced from the gas introducing unit 22 to the reformer 24.

As shown in the figure, this modification has a flow passage 56 from a blower 55 in the gas introduction part 22 of the reformer 20. As shown in FIG. 8, the gas introduction unit 22 has partition walls 23a and 23b provided therein so as to intersect each other, and partitions the interior of the introduction unit into four partition units 57a to 57d. And
The gas introduction part 22 connects the flow path 13, the flow path 15 and the flow path 56 to each partition part, and connects the partition part 57 a to the methane flow path 1.
3, the partition 57c is located at the end of the water vapor flow path 15, and the partition 57b and the partition 57d are located at the end of the air flow path 56 from the blower 55. That is, the gas introduction part 2
2, the air flow path end is interposed between the end of the methane flow path 13 and the end of the steam flow path 15, and methane, steam, and oxygen are individually supplied to the reformer 24 from each partition. Introduce.

Therefore, methane / steam /
When the reformer 24 is rotated while individually introducing oxygen,
Along with this rotation, air and steam can be introduced in this order to the reformer part that has been receiving methane. These can be introduced in the order of air and methane into the reformer part that has been receiving steam until then. These are repeated as the reformer 24 rotates.

In the reformer receiving the introduction of air, the reaction of the above-mentioned formula (3) (oxidation reaction of carbon) occurs, and the above-mentioned catalyst regeneration and the temperature rise of the reformer due to heat generation are brought about. Therefore, according to this modification as well, similar to the above-described embodiment, the reforming efficiency can be improved, and the effect of reducing the size of the device by reducing carbon monoxide can be obtained.

When the air is supplied in this way, it can be modified as follows. FIG. 9 is an explanatory diagram for explaining a modified example in which air introduction is also used. As shown in the figure, in this modified example, the gas introducing portion 22 has three dividing portions 57 formed by parallel dividing walls 23a and 23b.
a to 57c, and the partition 57a is divided into the methane flow path 13
, The partition 57c at the end of the water vapor flow path 15,
The partition 57 b is the end of the flow path 56 for the air from the blower 55. Even in this case, with the rotation of the reformer 24, air and steam are sequentially supplied to the reformer part that has been receiving methane, and air is supplied to the reformer part that has been receiving steam until then.・ These can be introduced in the order of methane. In the range shown by the dotted line in the figure, the reformer 24 is
It only receives air. However, this range is used for the rotary bearing of the reformer 24 and the like, and air aeration does not occur, so there is no problem.

Next, another embodiment will be described. This embodiment is characterized in that methane and steam are alternately introduced into different reformers, and the timing of this alternate introduction is different between the reformers. FIG. 10 is an explanatory diagram showing a schematic configuration of the fuel cell system 10A of the second embodiment, and FIG. 11 is an explanatory diagram explaining how methane and water vapor are introduced into the fuel cell system 10A.

The fuel cell system 10A of this embodiment is
The configuration of the reformer is different. That is, the reformer 20A of this embodiment has the gas distributor 60, the first reformer 61, and the second reformer 62. The gas distribution unit 60 has a built-in valve mechanism that switches the introduction destination of methane / steam from the methane gas supply device 12 and the steam supply device 14 to the first reformer 61 and the second reformer 62. Gas distribution to the reformer. Both the first reformer 61 and the second reformer 62 are
Similar to the previous example, a reforming catalyst (for example, a rhodium catalyst) capable of causing the decomposition reaction represented by the formula (1) is supported on the honeycomb gas flow channel.

The manner of gas distribution by the gas distributor 60 is as follows. As shown in FIG. 11, the gas distributor 60
Methane and steam are alternately introduced into the first reformer 61 and the second reformer 62, respectively. Therefore, each of the first reformer 61 and the second reformer 62 that receives the gas element introduction repeats the equations (1) and (2), as in the previous embodiment. Hydrogen / carbon dioxide production and carbon adsorption based on the reaction, and hydrogen production / carbon desorption (catalyst regeneration) based on the reaction of the formula (2) are repeated.

By the way, as is apparent from FIG. 11, while methane is being introduced into the first reformer 61, steam is introduced into the second reformer 62 and the first reformer 61 is introduced. While steam is being introduced, methane is being introduced to the second reformer 62. Therefore, while hydrogen / carbon dioxide production and carbon adsorption based on the reaction of equation (1) are being carried out in the first reformer 61, hydrogen production based on the reaction of equation (2) is carried out in the second reformer 62. -The carbon desorption (catalyst regeneration) is performed, and the fuel cell 40 downstream of the reformer merges with hydrogen / carbon dioxide based on the equation (1) and hydrogen based on the reaction of the equation (2) (reforming). Gas) is supplied. The same applies when the reaction of the formula (2) occurs in the first reformer 61 and the reaction of the formula (1) occurs in the second reformer 62. As a result, also in the fuel cell system 10A of this embodiment, as in the first embodiment,
It is possible to achieve various effects such that a hydrogen-rich gas having an extremely low carbon monoxide content can be continuously produced at a stable hydrogen concentration.

In this embodiment, the first reformer 61 and the second reformer 62 are separate bodies, but one reformer is the first reformer.
The reformer portion corresponding to the reformer 61 and the reformer portion corresponding to the second reformer 62 may be divided. Further, as shown in FIG. 6, it is possible to mix cathode offgas and air into the steam from the steam supply device 14.

In this embodiment, the introduction cycle of methane to the first reformer 61 and the introduction of methane to the second reformer 62 are shifted by a half cycle, and steam introduction is also the same. is there. For this reason, the hydrogen concentration of the combined gas is most stable downstream of the reformer, which is preferable. However, if the hydrogen concentration can be allowed to fluctuate to some extent, it is not always necessary that the deviation of the introduction period is a half period. Then, the phase difference of the introduction period can be adjusted according to the hydrogen concentration allowable width.

Next, a third embodiment will be described. This embodiment is characterized in that the reformer is rotated and the introduction of the reformer and the introduction of the purge gas for releasing carbon dioxide are carried out in the mixed state of methane and steam. FIG. 12 is an explanatory diagram showing a schematic configuration of the fuel cell system 10B of the third embodiment.

The fuel cell system 10B of this embodiment is
The reformer structure and the flow path structure for introducing gas are different. As shown in the figure, the reformer 20B rotates the reformer 24 via the drive device 26 similarly to the reformer 20 of the first embodiment, but introduces gas into both ends of the reformer 24. It has a section 22. The gas introduction portion 22L on the left side of the drawing is
The flow path end 22a is connected to the flow path 13 from the methane gas supply device 12 and the flow path 71 from the heat exchanger 70, and the flow path end 22b is connected to the exhaust flow path 72.

The heat exchanger 70 raises the temperature of the steam introduced from the steam supply device 14 to a predetermined temperature (for example, the carbon dioxide adsorption temperature of the carbon dioxide adsorbent described later). Exhaust gas passing through the exhaust passage 72 is used as the heat source.

The gas introducing unit 22L mixes methane from the flow path 13 and steam from the flow path 71 at the flow path end 22a, and then mixes this mixed gas (methane / steam mixed gas) with the reformer 24. To introduce.

On the other hand, the gas inlet 2 on the right side of the figure
2R supplies gas (reformed gas) to the anode of the fuel cell 40 from the flow path end 22a via the heat exchanger 73.
Further, the gas introduction unit 22R connects the anode off-gas passage 74 to the passage end portion 22b, and causes the anode off-gas to flow to the reformer 24.

That is, the left and right gas introducing portions 22R and 22L are
With respect to the reformer 24, the flow path end of the methane / steam mixed gas (flow path end 22a of the gas introduction part 22L) and the flow path end of the anode off gas (flow end 2 of the gas introduction part 22R).
2b) face each other.

The heat exchanger 73 uses the reformed gas from the reformer 24 as a heat source to raise the temperature of the anode off gas from the fuel cell 40, and then uses this anode off gas in the lower stage combustor 7.
Send to 5. The combustor 75 burns hydrogen in the anode off-gas while introducing air, and discharges the anode off-gas at a predetermined temperature (for example, the carbon dioxide release temperature of the carbon dioxide adsorbent described later) to the flow path end 22b of the gas introduction part 22R. To introduce.

In this case, the heat exchanger 73 lowers the temperature of the reformed gas to about 80 ° C. as the anode off-gas temperature rises and guides it to the fuel cell 40. If the reformed gas temperature cannot be lowered to about 80 degrees due to the heat balance of the anode off gas / reformed gas, another heat exchanger may be provided.

The reformer 24 is the same as that of the first embodiment in terms of its gas flow path configuration, and includes a reforming catalyst (for example, a rhodium catalyst) capable of causing steam reforming of methane, and a carbon dioxide adsorbing material. (For example, Li ₄ SiO ₄ , Li ₂ ZrO ₃ ,
(MgO, zeolite, etc.) is supported on the honeycomb-shaped gas flow channel. This carbon dioxide adsorbent has a property of exerting a function of adsorbing carbon dioxide under a predetermined temperature environment and releasing the adsorbed carbon dioxide when the temperature exceeds or falls below this temperature. Li used in this example
₄ SiO ₄ has a property of adsorbing carbon dioxide under a temperature environment of about 500 ° C. and releasing carbon dioxide under a temperature environment of about 600 ° C. Therefore, in this embodiment, the heat exchanger 70
Introduces the methane / steam mixed gas heated up to about 500 degrees into the reformer 20B, and the combustor 75 operates about 6
The reformer 2 uses the anode off-gas that has been heated up to about 00 degrees.
It is configured to be introduced at 0B.

In the fuel cell system 10B having the above structure,
While rotating the reformer 24 as in the first embodiment, the methane / steam mixed gas is introduced into the reformer 24 from the flow path end 22a of the gas introduction part 22L, and the flow path end part of the gas introduction part 22R is introduced. Anode off gas is introduced from 22b. Therefore,
Even in this embodiment, the reformer 24 receives the methane / steam mixture gas and receives the methane / steam mixed gas.
a mixed gas introduction part 24ab corresponding to a and the steam introduction part 24b of the first embodiment which receives the introduction of the anode off gas.
And a purge gas introduction portion 24bb corresponding to the above. And, the fuel cell system 10B has both of these introduction parts,
With the rotation of the reformer 24, the mixed gas and the purge gas are alternately introduced.

Therefore, in the mixed gas introducing portion 24ab,
Since it causes a reforming reaction in the coexistence of methane and steam,
It causes the methane reforming reaction represented by the above formulas. Moreover, the carried carbon dioxide adsorbent adsorbs the carbon dioxide produced by the reforming reaction to the carbon dioxide adsorbent (solid phase) and removes it from the reforming reaction system. Therefore, as described above, due to the equilibrium relationship, in the mixed gas introduction portion 24ab, the shift reaction of the formula is rate-controlled and the progress of the reverse shift reaction of the formula is suppressed. As a result, the hydrogen-rich reformed gas containing almost no carbon monoxide is supplied from the mixed gas introduction portion 24ab to the fuel cell 40.
Can be supplied to.

On the other hand, the mixed gas introduction portion 24ab which has undergone the reforming reaction and the carbon dioxide adsorption is newly introduced with the anode off gas from the combustor 75 as the reformer 24 rotates. Since this anode off-gas makes the gas passage portion (that is, the mixed gas introduction portion 24ab newly receiving the anode off-gas introduction) the temperature environment (about 600 degrees) at which the carbon dioxide adsorbent releases carbon dioxide, Causes the release of carbon dioxide from carbon adsorbents.
As a result, the carbon dioxide adsorbing function of the carbon dioxide adsorbing material is regenerated, so that the carbon dioxide adsorbing material reliably absorbs carbon dioxide at the next introduction of the methane / steam mixed gas. It should be noted that when carbon dioxide is released by the anode off gas, the reforming catalyst does not cause a reforming reaction of methane, and thus it is difficult to generate carbon monoxide.

As described above, in this embodiment, hydrogen / carbon dioxide production (reforming reaction) and carbon dioxide adsorption in the mixed gas introduction portion 24ab and function regeneration of the carbon dioxide adsorbent in the purge gas introduction portion 24bb are performed. , And simultaneously with the rotation of the reformer 24. Moreover, when the reforming reaction proceeds, the production of carbon monoxide is efficiently suppressed. As a result, in the present embodiment as well, as in the first embodiment, a hydrogen-rich gas having an extremely low carbon monoxide content can be continuously produced at a stable hydrogen concentration and supplied to the fuel cell 40, and the structure is simplified. It is possible to achieve such effects as downsizing and downsizing of the device.

Further, in this example, the anode off gas was used for releasing carbon dioxide. Therefore, it is not necessary to separately prepare a gas supply mechanism for releasing carbon dioxide, so that the structure can be simplified.

Further, in this embodiment, the shift reaction of the formula by taking out carbon dioxide to the outside of the system is controlled at a rate-determining rate, and a state in which the amount of carbon monoxide is small can be set in the catalytic reaction system. Therefore, there are the following advantages.

Usually, in the above-mentioned methane reforming process, the following reaction called a meteration reaction occurs.

CO + 3H ₂ → CH ₄ + H ₂ O

However, the CO involved in this reaction
Since the amount of (carbon monoxide) is low, the progress of these reactions can be suppressed. This meteration reaction is
Since the reaction system generates heat, the reformer 24 is not inadvertently heated by suppressing the reaction.

In the present embodiment, in consideration of the properties of the carbon dioxide adsorbent (Li ₄ SiO ₄ ) used, the temperature of the mixed gas is raised to about 500 ° C. at which adsorption can occur, and the amount of release can be increased. The anode off gas was heated to about 600 degrees. However, these temperatures may be appropriately determined according to the carbon dioxide adsorbent used. For example, when the carbon dioxide is released in a lower temperature environment than when carbon dioxide is adsorbed, the temperature rise of the anode off gas may be suppressed.

Further, in the present embodiment, the anode off gas is discharged from the heat exchanger 70 to the outside, but it may be circulated so as to be sent to the anode of the fuel cell 40. Since the anode off-gas is the exhaust of the hydrogen-rich gas sent from the reforming apparatus 20B in a state where the anode is almost free of carbon monoxide, the gas contains almost no carbon monoxide in the first place. In addition, since it does not contain a substance that participates in the reaction with the reforming catalyst, it is difficult for the situation where carbon monoxide is generated when it is introduced into the reformer 24. Therefore, even if the anode off-gas from the heat exchanger 70 is circulated to the fuel cell 40 as described above, a problem such as deterioration of cell performance does not occur.

Also in the present embodiment, the oxygen-containing gas may be mixed with the mixed gas of methane and steam. For example, air may be introduced into the heat exchanger 70 from a blower, or cathode off gas may be introduced. If oxygen is introduced in this manner, carbon monoxide can be converted to carbon dioxide by the introduced oxygen and can be adsorbed, so that the production of carbon monoxide can be suppressed more reliably.

Next, another embodiment will be described. In this embodiment, the mixed gas of methane / steam and the anode off gas are alternately introduced into different reformers, and the timing of this alternate introduction and the switching of the gas discharge from the reformers are different between the reformers. It is characterized in that it was made. FIG.
Is an explanatory view showing a schematic configuration of a fuel cell system 10C of the fourth embodiment, and FIG. 14 is an explanatory view explaining a state of alternate gas introduction and gas discharge in the fuel cell system 10C.

Even in the fuel cell system 10C of this embodiment, the structure of the reformer and the structure of the flow path for introducing gas are different. As shown in the figure, the reformer 20C has a first reformer 61 and a second reformer 62, as well as the reformer 20A of the second embodiment. It has a distributor 60 and a mixer 77. The mixer 77 includes the methane from the methane gas supply device 12 and the steam supply device 14
The steam from is received through heat exchange in the heat exchanger 70, the two are mixed, and introduced from the flow path 71 to the gas distributor 60 on the upstream side.

The gas distributor 60 on the upstream and downstream sides of the reformer switches the gas distribution destination as in the second embodiment, and the gas distributor 60 on the upstream side mixes methane and steam from the mixer 77. Gas distribution of the gas and the anode off-gas from the combustor 75 is switched to either the first reformer 61 or the second reformer 62. The gas distributor 60 on the downstream side of the reformer has the first
The distribution of the gas from the reformer 61 and the gas from the second reformer 62 is switched between the fuel cell 40 passing through the heat exchanger 73 and the heat exchanger 70. Both the first reformer 61 and the second reformer 62 are reforming catalysts (e.g., rhodium) capable of causing the steam reforming reaction (-formula) of methane, like the reformer 24 in the third embodiment. A catalyst) and a carbon dioxide adsorbent are supported on the honeycomb-shaped gas flow channel.

The manner of gas distribution by the gas distributors 60 above and below the reformer is as follows. As shown in FIG. 14, the gas distributor 60 on the upstream side of the reformer includes, in each of the first reformer 61 and the second reformer 62, the mixed gas of methane and steam from the mixer 77 and the combustion. Predetermined temperature (approx. 600
Of the anode off gas is alternately introduced. In this case, the mixed gas is brought to the above-mentioned temperature of about 500 degrees by the temperature rise of steam in the heat exchanger 70. Therefore,
Each of the first reformer 61 and the second reformer 62 that receives such gas introduction is similar to the third embodiment in that the steam reforming reaction of formula (1) to carbon dioxide release by the anode off gas (carbon dioxide adsorbing material). Repeat) and. Even in this case, since carbon dioxide is adsorbed similarly to the third embodiment, the reformed gas resulting from the steam reforming reaction of the formulas is hydrogen-rich and contains almost no carbon monoxide. Becomes

The gas distributor 60 on the downstream side of the reformer is
While the first reformer 61 receives the mixed gas, the reformed gas passes through the heat exchanger 73 and the fuel cell 40.
Of the passing gas (that is, carbon dioxide released by the above-mentioned anode off-gas) while the first reformer 61 is receiving the anode off-gas.
Are introduced into the heat exchanger 70. Further, the gas distributor 60 on the downstream side supplies the reformed gas to the anode of the fuel cell 40 via the heat exchanger 73 while the second reformer 62 receives the mixed gas. Introduce this second reformer 62
While the anode off gas is being introduced, the passing gas (that is, the carbon dioxide released by the anode off gas described above) is introduced into the heat exchanger 70.

By the way, as is apparent from FIG. 14, while the mixed gas is being introduced into the first reformer 61, the second reformer 61
While the anode off gas is introduced into the reformer 62 and the anode off gas is introduced into the first reformer 61, the mixed gas is introduced into the second reformer 62. Therefore,
While the first reformer 61 is producing hydrogen and carbon dioxide based on the above-mentioned steam reforming reaction and adsorbing carbon dioxide, the second reformer 62 releases carbon dioxide from the anode offgas (carbon dioxide adsorbing material). (Regeneration), and while the second reformer 62 is performing hydrogen / carbon dioxide production and carbon dioxide adsorption based on the above-mentioned steam reforming reaction, the first reformer 61 causes carbon dioxide produced by the anode offgas. Release (regeneration of carbon dioxide adsorbent) is performed. Then, the reformed gas rich in hydrogen and containing almost no carbon monoxide from both reformers is subjected to gas distribution by the gas distributor 60 on the downstream side of the reformer and supplied to the fuel cell 40 on the downstream side of the reformer. To be done.
As a result, the hydrogen-rich reformed gas is alternately supplied to the fuel cell 40 from both the first reformer 61 and the second reformer 62, and the hydrogen-rich gas is continuously supplied as a whole.
Also in the heat exchanger 70, the released carbon dioxide is alternately supplied from both the first reformer 61 and the second reformer 62, and this gas is used as a heat source to continuously raise steam. Warm.

As described above, according to the fuel cell system 10C of the fourth embodiment, as in the above-described embodiments, the hydrogen-rich gas containing extremely low carbon monoxide is added,
Various effects such as continuous production with a stable hydrogen concentration can be achieved.

In this embodiment as well, the first reformer 61 and the second reformer 62 are separate bodies, but one reformer corresponds to the first reformer 61. It may be divided into a pouch part and a reformer part corresponding to the second reformer 62. Further, as shown in FIG. 6, it is possible to mix cathode offgas and air into the steam from the steam supply device 14.

Further, in this embodiment, regarding the introduction of the mixed gas into the first reformer 61, the introduction of the mixed gas into the second reformer 62, and the introduction of the anode off gas, the phase difference between the introduction cycles is half a cycle. If so, the hydrogen concentration can be made the most stable as in the previous embodiment, which is preferable. However, the phase difference of the introduction period may be adjusted according to the hydrogen concentration allowable range.

The embodiments of the present invention have been described above.
The present invention is not limited to the above examples and embodiments, and it goes without saying that the present invention can be implemented in various modes without departing from the gist of the present invention.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of this embodiment.

FIG. 2 is a reformer 2 included in the fuel cell system 10.
It is explanatory drawing explaining the schematic structure of 0.

FIG. 3 is an explanatory diagram showing a schematic configuration of the reforming device 20 in a sectional view taken along line 3-3 in FIG.

FIG. 4 is a rotation operation of a reformer 24 of a reformer 20 and (1)
It is explanatory drawing which links | relates and demonstrates the mode of reaction of Formula and (2) Formula.

FIG. 5 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of a modified example.

FIG. 6 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of another modification.

FIG. 7 is an explanatory diagram showing a schematic configuration of a fuel cell system 10 of another modification.

FIG. 8 is an explanatory diagram for explaining how gas is introduced from the gas introduction unit 22 into the reformer 24.

FIG. 9 is an explanatory diagram for describing a modified example when air is also used.

FIG. 10 is an explanatory diagram showing a schematic configuration of a fuel cell system 10A of a second embodiment.

FIG. 11 is an explanatory diagram for explaining how methane and water vapor are introduced into the fuel cell system 10A.

FIG. 12 is an explanatory diagram showing a schematic configuration of a fuel cell system 10B according to a third embodiment.

FIG. 13 is an explanatory diagram showing a schematic configuration of a fuel cell system 10C according to a fourth embodiment.

FIG. 14 is an explanatory diagram illustrating the manner of alternate gas introduction and gas discharge in the fuel cell system 10C.

[Explanation of symbols]

10 to 10 C ... Fuel cell system 12 ... Methane gas supply device 13 ... Flow path 14 ... Steam supply device 15 ... Flow path 20-20C ... Reforming device 22 ... Gas introduction section 22L, 22R ... Gas introduction section 22a ... Channel end 22b ... Channel end 23 ... Partition wall 23a, 23b ... Partition walls 24 ... Reformer 24a ... Methane introduction part 24b ... Water vapor introduction part 24ab ... Mixed gas introduction part 24bb ... Purge gas introduction part 25t0 ... marking line 26 ... Drive device 26a ... Water vapor transition part 26b ... Methane transition part 40 ... Fuel cell 42 ... Blower 44 ... Exhaust flow path on cathode side 45 ... Valve 50 ... Supply device 51 ... Preliminary reformer 55 ... Blower 56 ... Channel 57a ... division 57a-57d ... Compartment 60 ... Gas distribution unit 61 ... First reformer 62 ... Second reformer 70 ... Heat exchanger 71 ... Channel 72 ... Exhaust flow path 73 ... Heat exchanger 74 ... Flow path 75 ... Combustor 77 ... Mixer

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4G140 EA03 EA06 EA07 EB03 EB04                       EB12 EB18 EB27 EB41 EB42                 5H027 AA02 BA01 BA10 BA16

Claims (11)

[Claims] 1. A reformer for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound, the reformer having a reforming catalyst used for the steam reforming, and the hydrocarbon. It has a first flow path for introducing a raw fuel gas containing a system compound and a second flow path for introducing steam, and the ends of the first and second flow paths are opposed to the reformer and the raw material gas is provided. An introduction unit for introducing the steam into the reformer, and a rotation operation unit for relatively rotating the introduction unit and the reformer around a gas flow direction in the reformer. A reformer characterized by: 2. The reformer according to claim 1, wherein the reformer rotates around the flow direction. 3. The reformer according to claim 1, wherein the second flow path introduces an oxygen-containing gas together with the steam. 4. The reforming apparatus according to claim 3, wherein the second flow path is a cathode offgas of a fuel cell that is supplied with hydrogen-rich reformed gas as fuel gas from the reformer to generate electricity. Leading reformer. 5. The reforming apparatus according to claim 1, wherein the introduction part has an oxygen introduction flow path for introducing an oxygen-containing gas, and an end of the oxygen introduction flow path is connected to the first flow path. A reformer interposed between an end and an end of the second flow path. 6. A reformer for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound, the first and second reformers having a reforming catalyst used for the steam reforming. And a first introducing portion for alternately introducing a raw fuel gas containing a hydrocarbon compound and steam to the first reformer, and a raw fuel gas and steam to the second reformer. And a downstream flow path for introducing the reformed gas from the first and second reformers together and guiding the combined gas to the downstream side. Is a reformer characterized in that while one guides the raw fuel gas, the other guides the steam. 7. A reformer for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound, the reforming catalyst being used for the steam reforming, and an adsorption having a carbon dioxide adsorption function. A reformer having a material, a first flow path for introducing a raw fuel gas containing the hydrocarbon compound and steam, and a purge gas for introducing a carbon dioxide adsorbed carbon dioxide from the adsorbent. An introduction part having two flow paths, the ends of the first and second flow paths facing the reformer and introducing the mixed gas of the raw material gas and the steam and the purge gas into the reformer. And a rotation actuating means for relatively rotating the introduction part and the reformer around a gas flow direction in the reformer. 8. A reformer for producing a hydrogen-rich reformed gas through steam reforming of a hydrocarbon compound, the reforming catalyst being used for the steam reforming, and an adsorption having a carbon dioxide adsorption function. A first and a second reformer having a material, and a mixed gas of a raw fuel gas containing a hydrocarbon-based compound and steam, and carbon dioxide adsorbed from the adsorbent to the first reformer. A first introducing part for alternately introducing a purge gas capable of causing carbon dioxide release; and a second introducing part for alternately introducing the mixed gas and the purge gas to the second reformer, the first introducing part The reformer, wherein one of the section and the second introduction section guides the purge gas while the other guides the mixed gas. 9. The reforming apparatus according to claim 7, wherein the purge gas is an anode offgas of a fuel cell that is supplied with hydrogen-rich reformed gas from the reformer as fuel gas to generate electric power. It is said that the reformer. 10. A fuel cell system comprising a fuel cell which receives supply of a hydrogen-rich fuel gas and an oxygen-containing gas, and which promotes an electrochemical reaction of hydrogen and oxygen to generate electric power. 9. A fuel cell system, comprising the reformer according to any one of 9 to 10 and supplying the hydrogen-rich reformed gas produced by the reformer as the fuel gas to the fuel cell. 11. A method for producing a hydrogen-rich reformed gas by subjecting a hydrocarbon-based compound to steam reforming, wherein the hydrocarbon-based compound is added to a reformer having a reforming catalyst used for the steam reforming. In introducing the raw fuel gas and steam containing, the reformer is divided into an introduction point of the raw fuel gas and an introduction point of the steam to the reformer, and the introduction point where the raw fuel gas was introduced A method for reforming, characterized by repeating the steps of introducing the water vapor into the steam and introducing the raw fuel gas into the introduction location where the water vapor was introduced.