JP3369846B2 - Reactor for fuel cell - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell reactor such as a reformer, a CO shift converter, a desulfurizer, etc., and more particularly to a fuel cell reactor having a double cylinder tube structure provided around a high temperature body. Regarding

[0002]

2. Description of the Related Art In general, a fuel cell supplies hydrogen-rich gas and air to a cell provided with electrodes and causes them to react electrochemically to generate electricity. As a hydrogen-rich gas,
A reformed gas produced by mixing raw materials such as natural gas, methanol, and naphtha with steam and reacting them with a reforming catalyst is widely used. The reforming reaction here is represented by a reaction formula as shown in the following chemical formula 1, and is mainly performed at a high temperature of about 700 to 800 ° C.

[0003]

[Chemical 1] The reformed gas generated here contains a certain amount (tens of percent) of carbon monoxide, but carbon monoxide causes a decrease in the catalytic ability of the electrode. In many reforming systems, carbon monoxide in the reformed gas is converted into carbon dioxide by the reaction of the following chemical formula 2 through a CO shifter equipped with a catalyst and then supplied to the fuel cell. The CO shift converter is operated at a lower temperature (about 180 to 300 ° C.) than the reformer, but when the reaction of Chemical formula 2 reaches an equilibrium state, the lower temperature indicates that the carbon monoxide concentration is lower. This is because the equilibrium shifts so that

[0004]

[Chemical 2] In such a reforming system, as shown in FIG.
Appearance A CO reformer in which a conversion catalyst is filled in a double cylindrical tube is provided around a cylindrical reformer, and the heat of the reformer is used to heat the CO transformer. You can
It is excellent in reducing heat loss (for example, JP-A-6-
140068).

By the way, in the CO converter having the double cylindrical tube structure, an annular buffer tank 139 is provided along the inlet side of the catalyst layer 135, and a modified one introduced into the buffer tank 139 from the gas inlet 142. The quality gas is divided into two, is distributed to the catalyst layer 135 while swirling in the buffer tank 139 about a half turn, and is further converted while flowing in the catalyst layer 135 in the pipe axis direction.

[0006]

This CO transformer 104
Since the reformed gas flowing in the buffer tank 139 receives heat from the high-temperature reformer 103, the temperature rises as it is separated from the gas inlet 142, and the temperature of the gas on the side opposite to the gas inlet 142 is the highest. Becomes higher. That is, the catalyst layer 135
The temperature of the reformed gas distributed to the tank becomes uneven.

If the temperature of the reformed gas entering the catalyst layer 135 is non-uniform, the gas temperature is partially lowered and the conversion reaction becomes insufficient, or the gas temperature is partially raised and carbon monoxide is increased. There is a tendency that the concentration of is not sufficiently reduced. It should be noted that such a problem is not limited to the CO shifter, and is, for example, a desulfurizer having a double-cylindrical tube structure provided on the outer circumference of a pipe through which a high-temperature fluid flows and having a catalyst for desulfurization inside. In the same manner, the gas temperature entering the catalyst layer becomes non-uniform, which may cause an undesirable state for the desulfurization reaction.

In view of the above-mentioned problems, the present invention aims to make the temperature of the gas distributed to the catalyst layer uniform in a reactor for a fuel cell having a double cylinder tube structure provided around a high temperature body. Another object of the present invention is to provide a product capable of favorably carrying out a catalytic reaction.

[0009]

In order to achieve the above object, the present invention provides a preheating tank for absorbing heat transferred from a high temperature body to a buffer tank in a fuel cell reactor having such a double tube structure. A gas communication port from the preheating tank to the buffer tank was provided at a position that was provided adjacent to the buffer tank and was separated from the gas inlet of the preheating tank by approximately half a circumference in the annular space.

In the fuel cell reactor having such a structure, the gas flowing from the gas inlet is branched in the preheating layer and swirled in the preheating tank for about half a turn toward the gas communication port to join the gas. It flows from the connection port to the buffer tank. Then, it branches in the buffer tank and is distributed to the catalyst layer while turning about a half turn toward the gas inlet in the buffer tank. When the gas flows in the preheating tank, the temperature rises while absorbing the heat transmitted from the high temperature body to the buffer tank. On the other hand, when the gas flows in the buffer layer, it receives heat from the high temperature body and tries to rise in temperature, but the heat is absorbed by the gas in the preheating tank.

Therefore, when the gas flows in the preheating tank, the temperature is raised, and when the gas is flowing in the buffer tank, the heat received from the high temperature body and the heat absorbed in the preheating tank are balanced to suppress the temperature rise. Therefore, the temperature distribution of the gas distributed to the catalyst tank can be made uniform. Here, the preheating tank and the buffer tank may be partitioned by the first partition plate made of a heat conductive member, and the gas communication port may be opened in the first partition plate. In this case, CO
The structure of the transformer can be relatively simple.

Further, the preheating tank may be inserted between the buffer tank and the outer tube. In this case, the buffer tank is heated from the inside by the high temperature body and from the outside by the preheating tank. To be cooled. Therefore, it is easy to adjust the balance between heating and cooling when the gas flows through the buffer tank.
Alternatively, the first partition plate may be formed in a flat plate shape and its plate surface may be provided in a direction substantially perpendicular to the tube axis. In this case, the preheating tank also receives heat from the high temperature body, so that the temperature raising effect is large when the gas flows through the preheating tank. In addition, since the first partition plate has a flat plate shape, it is easy to manufacture and the position of the first partition plate in the space can be easily adjusted.

Further, it is also possible to use a heat conductive tube as the first partition plate and provide it in the buffer tank. In this case, the preheating tank and the buffer tank can be provided relatively easily. You can Also, the preheating tank may be inserted between the inner peripheral plate and the buffer tank. In this case, the heat transfer from the high temperature body to the buffer tank is blocked by the preheating layer, and the gas flowing through the preheating tank is blocked. Since this absorbs this heat, the temperature raising effect is large when the gas flows through the preheating tank.

Further, a second partition plate having a plurality of gas distribution holes may be inserted between the buffer tank and the catalyst layer. In this case, the gas distributed to the catalyst layer is the second partition plate. It is rectified by the partition plate and the gas is more uniformly distributed to the catalyst layer.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) (Explanation of overall configuration of reforming system) FIG. 1 is a schematic configuration diagram of a fuel gas reforming system including a CO transformer having a double cylindrical tube structure according to an embodiment of the present invention. is there.

This fuel gas reforming system includes a desulfurizer 1 for removing sulfur components from a fuel gas raw material (natural gas, city gas, etc.) and steam reforming of the fuel gas to produce a hydrogen-rich reformed gas. A columnar reformer 3, a CO shifter 4 for converting carbon monoxide in the reformed gas into carbon dioxide with a double cylindrical tube structure provided on the outer periphery of the reformer 3, and a CO shifter 4 are provided. A water pipe 5 for cooling, a steam separator 6 for separating and removing water in steam, a heat exchanger 7 for heating steam with the heat of the reformed gas from the reformer 3, and steam for fuel gas. It is composed of an ejector 8 and the like for mixing.

Further, a pipe A for sending fuel gas from the ejector 8 to the reformer 3 and a CO from the reformer 3 via the heat exchanger 7
A piping system such as a piping B for sending the reformed gas to the shift converter 4 and a piping C for sending the steam from the steam separator 6 to the ejector 8 via the heat exchanger 7 are also provided. The desulfurizer 1 has a cylindrical container filled with a desulfurization catalyst, and a heater 2 for keeping the desulfurizer 1 at an operating temperature (200 to 300 ° C.) is disposed around the catalyst. .

FIG. 2 is a sectional view of the reformer and CO transformer of the fuel gas reforming system shown in FIG. 1, and FIG. 3 is a perspective view of the CO transformer. The reformer 3 has a cylindrical outer container 11
A cylindrical combustion tube 12 inserted from the lower surface 11b side of the outer container 11 to the central portion, a burner 13 attached to the lower side of the combustion tube 12, and an upper surface 11a side of the outer container 11. And a reaction tank 20.

The burner 13 is used for the fuel gas raw material and the fuel cell 1.
The unreacted gas from No. 4 is mixed with air supplied from an external fan (not shown), burned in the combustion cylinder 12, and the high temperature combustion gas is discharged from the combustion cylinder 12. Reaction tank 20
Is a double cylindrical tubular container surrounded by a cylindrical inner peripheral plate 21 and an outer peripheral plate 22, a circular outer top plate 23 and an inner top plate 24, and an annular lower plate 25. Catalyst layer 2
6 is provided and configured. Inner peripheral plate 21 and outer peripheral plate 2
The gap 2 is divided into inner and outer gaps by a cylindrical partition plate 27, and the catalyst layer 26 has the reforming catalyst in the inner gap between the inner peripheral tube 21 and the partition plate 27. Filled and formed.

A gas inlet 28a is provided at the center of the outer top plate 23, and a gas outlet 28b is provided at the upper end of the outer peripheral plate 22. The fuel gas containing water vapor sent from the gas inlet 28a flows in the catalyst layer 27. As it descends, it is reformed into a hydrogen-rich reformed gas by a catalytic reaction, goes up the outer gap between the outer peripheral plate 22 and the partition plate 27, and flows into the pipe B from the gas outlet 28b.

A concave space surrounded by the inner pipe 21 and the inner top plate 24 is formed on the lower surface side of the reaction tank 20, and the combustion cylinder 12 is inserted in the concave space. The high-temperature combustion gas discharged from the upper end of the combustion cylinder 12 descends through the gap between the combustion cylinder 12 and the inner pipe 21 as shown by the solid arrow G in FIG.
1, and the gas is discharged from a combustion gas discharge port 29 attached near the upper end of the side surface of the outer container 11, and this combustion gas causes the catalyst layer 26 to have a temperature (7
It is designed to be heated to 100 to 800 ° C.

The CO converter 4 comprises a cylindrical catalyst layer in a double cylindrical tubular container 30 composed of a cylindrical inner peripheral plate 31 and an outer peripheral plate 32, and an annular upper plate 33 and a lower plate 34. 35 is provided and configured. The CO shift converter 4 is provided around the outer periphery of the reformer 3 via a heat insulating material 9 so as to be integrated, and the whole is covered with the heat insulating material 10. This structure makes the device compact and
The heat released from the reformer 3 is used to heat the CO shift converter 4, and the heat released to the outside is also reduced. In addition, CO
The detailed configuration of the transformer 4 will be described later.

(Description of Operation of Reforming System) The operation of the reforming system will be described with reference to FIG. The fuel gas raw material is supplied to the desulfurizer 1 heated by the heater 2 for desulfurization. Then, it is mixed with the steam from the steam separator 6 in the ejector 8, passes through the pipe A,
It is supplied to the reformer 3 heated to about 750 ° C. by the burner 13.

In the reformer 3, the fuel gas is steam-reformed by the reactions of the above chemical formulas 1 and 2, and a hydrogen-rich reformed gas is produced. ing. The reformed gas discharged from the reformer 3 to the pipe B has a high temperature (about 400 ° C.), but when passing through the heat exchanger 7, it is supplied from the steam separator 6 to the ejector 8 through the pipe C. In order to heat the generated steam, it is cooled to about 200 ° C. and sent to the CO shift converter 4.

The CO shift converter 4 is cooled by the water pipe 5 while being heated by the heat from the reformer 3 and kept at about 180 to 300 ° C. In the CO shift converter 4, carbon monoxide contained in the reformed gas from the reformer 3 is converted into carbon dioxide by the reaction of the above chemical formula 2, and the reformed gas having a low carbon monoxide concentration is used in the fuel cell. Is supplied. Water pipe 5 is CO transformer 4
Heat is generated to generate steam. The steam separator 6 separates steam supplied from an external boiler (not shown) and the water pipe 5 into steam.

(Description of Structure and Effect of CO Transformer 4) The detailed structure of the CO converter 4 will be described with reference to FIGS. An annular rectifying plate 36 is attached to the lower portion of the container 30, and the space inside the container 30 is vertically divided by the rectifying plate 36. The above-mentioned catalyst layer 35 is formed by filling the catalyst for the carbon monoxide conversion reaction on the catalyst supporting net plate 37 placed on the rectifying plate 36.

The annular space below the current plate 36 is partitioned by a cylindrical partition plate 38 into an inner space (buffer tank 39) and an outer space (preheating tank 40).
A plurality of distribution holes 51 (not shown in FIGS. 2 and 3; see FIG. 4) for sending the reformed gas from the buffer tank 39 to the catalyst layer 35 are provided in the current plate 36 in a circumferential shape at substantially equal intervals. There is. The partition plate 38 is formed of a heat conductive material such as metal, and heat is exchanged between the preheating tank 40 and the buffer tank 39.

In the container 30, an annular space 41 is formed above the catalyst layer 35, and the reformed gas after the conversion reaction is collected in this space 41. Perimeter plate 3
2, a gas inlet 42 for introducing the reformed gas into the preheating tank 40.
And a gas outlet 43 for discharging the reformed gas from the space 41 is provided. Further, the partition plate 38 has gas inlets 42 and 1
A window 38a is opened at a position on the opposite side of 80 °, and a preheating tank 40 is provided.
The reformed gas is supplied to the buffer layer 39 through the window 38a.

The above-mentioned water pipe 5 is spirally wound around the outer peripheral plate 32 of the CO shift converter 4. The water pipe 5 is arranged so that the lower part of the catalyst layer 35 can be controlled to a relatively high temperature (about 300 ° C.) and the upper part of the catalyst layer 35 can be controlled to a relatively low temperature (about 200 ° C.). This is because when the reformed gas flows in the catalyst layer 35, the reaction of Chemical formula 2 is first advanced to the equilibrium state, and then the reaction is controlled so as to move the equilibrium in the direction of lowering carbon monoxide.

The thickness W of the catalyst layer 35 is set based on the amount of catalyst required according to the amount of fuel gas to be processed.
Since the temperature difference between the inner side and the outer side of the catalyst layer 35 increases with increasing, it is desirable to set it so as not to increase so much. 4A and 4B are schematic cross-sectional views of the CO transformer 4 in the vertical direction and the horizontal direction. The function and effect of the CO transformer 4 will be described with reference to FIG.

The flow of the reformed gas is shown by a thick line arrow in the figure. The reformed gas sent from the gas inlet 42 branches in the preheating tank 40 toward the window 38a by about 180 °, respectively.
After circling at ℃, they merge and pass through the window 38a to form the buffer layer 3
It is sent to 9. Then, it branches in the buffer layer 39 and is distributed to the catalyst layer 35 through the distribution holes 51 while swirling about 180 ° C. toward the gas inlet 42. The distributed reformed gas undergoes a conversion reaction while rising in the catalyst layer 35, gathers in the space 41, and is sent to the fuel cell from the gas outlet 43.

The flow of heat with respect to the reformed gas is shown by an outline arrow in the figure. The reformed gas flowing through the preheating tank 40 is
Heat is received from the reformed gas flowing through the buffer tank 39 through the partition plate 38. On the other hand, the reformed gas flowing in the buffer tank 39 receives heat from the reformer 3, but the heat is absorbed by the reformed gas flowing in the preheating tank 40 via the partition plate 38. Therefore, when the reformed gas flows through the preheating tank 40, the temperature is raised, and when the reformed gas flows through the buffer layer 39, the transfer of heat can be balanced to reduce the change in temperature.

As a result, the catalyst tank 3 passes through the distribution hole 51.
Since the temperature of the reformed gas distributed to 5 is made uniform, it is possible to form an environment suitable for reducing the concentration of carbon monoxide in the reformed gas fed into the fuel cell. (Embodiment 2) The reforming system of this embodiment is the same as that of the first embodiment, but instead of the CO transformer 4, CO
A transformer 70 is used.

5A and 5B are schematic cross-sectional views of the CO transformer 70 in the vertical and horizontal directions. The CO transformer 70 has the same configuration as that of the CO transformer 4 of the first embodiment, but in the CO transformer 4, the annular space below the rectifying plate 36 is partitioned by the cylindrical partition plate 38. On the other hand,
In the CO shift converter 70, this space is vertically divided by a flat annular partition plate 71 (the plate surface of the partition plate 71 is perpendicular to the pipe axis direction) to form a buffer tank 72 and a preheating tank 73. Is different.

The partition plate 71 is made of a heat conductive material, as in the partition plate 38 of the first embodiment.
A window 71a is opened at a position opposite to 2 ° by 180 °. The function and effect of the CO transformer 70 will be described with reference to FIG. The flow of the reformed gas is indicated by a thick line arrow in the figure. The reformed gas sent from the gas inlet 42 is branched in the preheating tank 73 in the same manner as in the first embodiment, and is branched into the window 7.
After turning 180 ° each toward 1a, they merge and are fed into the buffer layer 72 through the window 71a. Then, it branches in the buffer layer 72 and is distributed to the catalyst layer 35 through the distribution holes 51 while swirling about 180 ° C. toward the gas inlet 42.

The flow of heat with respect to the reformed gas is shown by a white arrow in the figure. The reformed gas flowing through the preheating tank 73 receives heat from the reformed gas flowing through the buffer tank 72 via the partition plate 71, which is the same as in the first embodiment, and at the same time, the reformer 3 also receives heat. Heat is received via the peripheral plate 31. on the other hand,
The reformed gas flowing through the buffer tank 72 receives heat from the reformer 3 as in the first embodiment, but the heat is absorbed by the reformed gas flowing through the preheating tank 73 through the partition plate 71.

Therefore, as in the first embodiment, when the reformed gas flows through the preheating tank 73, the temperature rises, and when the reformed gas flows through the buffer tank 72, the heat transfer is balanced to reduce the temperature change. can do. In addition, the effect of raising the temperature of the reformed gas flowing through the preheating tank 73 is larger than that in the first embodiment. (Embodiment 3) The reforming system of this embodiment is the same as that of the first embodiment, except that instead of the CO transformer 4, CO
A transformer 80 is used.

6A and 6B are schematic sectional views of the CO transformer 80 in the vertical and horizontal directions. The CO transformer 80 of the present embodiment has the same configuration as the CO transformer 4 of the first embodiment, but in the CO transformer 4, the inside of the partition plate 38 is the buffer tank 39 and the outside thereof is the preheating tank 40. On the other hand, in the CO transformer 80, the outer space formed by partitioning the annular space below the flow regulating plate 36 with the cylindrical partition plate 81 is the buffer tank 82, and the outer space is the preheating tank 83.

Although the partition plate 38 of the first embodiment is made of a heat conductive material, the material of the partition plate 81 need not be a heat conductive material. Further, similar to the partition plate 38 of the first embodiment,
A window 81a is opened in the partition plate 81 at a position opposite to the gas inlet 42 by 180 °. The gas inlet 42 extends from the outer peripheral plate 32 through the buffer tank 82 and is connected to the preheating tank 83.

The function and effect of the CO transformer 80 will be described with reference to FIG. The flow of the reformed gas is shown by a thick arrow in the figure. The reformed gas sent from the gas inlet 42 is branched in the preheating tank 83 and swirled by about 180 ° C. toward the window 81a, and then merges into the buffer tank through the window 81a, as in the first embodiment. Sent to 82. And it branches in the buffer tank 82, and gas inlet 4
It is distributed to the catalyst layer 35 through the distribution hole 51 while swirling about 180 ° C. toward 2.

The flow of heat with respect to the reformed gas is shown by a white arrow in the figure. The reformed gas flowing through the preheating tank 83 is
Heat is received from the reformer 3 via the inner peripheral plate 31. On the other hand, since the preheating tank 83 is inserted between the reformer 3 and the buffer tank 82, the reformed gas flowing through the buffer tank 82 does not receive much heat from the reformer 3. Therefore, it is possible to raise the temperature when the reformed gas flows through the preheating tank 83 and reduce the temperature change when flowing through the buffer tank 82.

(Embodiment 4) The reforming system of this embodiment is the same as that of the first embodiment, but a CO transformer 90 is used instead of the CO transformer 4. Figure 7
(A), (b) is a schematic sectional drawing of the CO transformer 90 of the vertical direction and the horizontal direction.

The CO transformer 90 has the same structure as that of the CO transformer 4 of the first embodiment, except that a heat conductive tube is wound in a circular shape in the annular space below the flow regulating plate 36. A ring pipe 91 is installed, an outer space of the ring pipe 91 serves as a buffer tank 92, and an inner space thereof serves as a preheating tank 93. As with the partition plate 38 of the first embodiment, the ring tube 91 has a window 91a at a position 180 ° opposite to the gas inlet 42.

The gas inlet 42 penetrates the buffer tank 92 from the outer peripheral plate 32 and is connected to the preheating tank 93. In the figure, the flow of the reformed gas is indicated by a thick arrow, and the flow of heat to the reformed gas is indicated by a white arrow. The flow of the reformed gas and the heat flow to the reformed gas are the same as those in the first embodiment,
Therefore, the temperature of the gas distributed from the buffer tank 92 to the catalyst tank 35 through the distribution holes 51 is made uniform.

[0045]

【Example】

(Example) The reforming system of this example is based on the first embodiment. The reformer 3 is of the 3 kW class and has an outer diameter of about 150 mm and a height of about 500 mm.

The CO shifter 4 has a height of about 400 mm, the inner peripheral plate 31 has a diameter of about 200 mm when the thickness of the heat insulating material 9 is added to the outer diameter of the reformer 3 of 150 mm, and the outer peripheral plate 32 has a diameter of about 200 mm. Three
00 mm, the height of the catalyst layer 35 is about 300 mm, the catalyst layer 3
The thickness W of 5 is set to about 50 mm. The inner peripheral plate 31, the outer peripheral plate 32, the upper plate 33, the lower plate 34, the rectifying plate 36, and the partition plate 38 of the CO transformer 4 are all stainless steel plates.

(Conventional example) The reforming system of this conventional example is the same as the above-mentioned example, but C without a preheating tank is provided.
The difference is that the O-transformer 104 is used. 8A and 8B are schematic cross-sectional views of the CO transformer 104 in the vertical direction and the horizontal direction.

The CO transformer 104 has the same structure as that of the CO transformer 4 of the first embodiment, but the partition plate 38 is not provided, and the entire annular space below the flow regulating plate 36 is the buffer tank 139. Has become. In the CO shift converter 104, the reformed gas fed from the gas inlet 42 is branched in the buffer tank 139 to reach about 1 as indicated by a thick arrow in the figure.
It is distributed to the catalyst layer 35 through the distribution hole 51 while swirling at 80 ° C.

As indicated by the white arrow in the figure, the reformed gas flowing through the buffer tank 139 receives heat from the reformer 3, but absorbs heat in the preheating tank as in the case of the CO shift converter 4. The temperature rises because it cannot be done. Therefore, the temperature of the gas distributed to the catalyst tank 35 becomes non-uniform. (Experiment) Operation was performed using the reforming systems of the above Examples and Comparative Examples, and the temperature distribution in the catalyst layers of the CO shifters 4 and 104 was measured during steady operation.

As shown in FIGS. 4 (a) and 8 (a), the temperature is measured at the inlet and outlet positions E, the lower position L, the central position M, and the upper position H of the catalyst layer 35 in the vertical direction. Figure 4
(B), as shown in FIG. 8 (b), along the circumference of the CO transformer from the position of the gas inlet, 0 ° (position α), 90 ° (position β), 180 ° (position γ), 270 ° (position δ)
The measurement was performed for the horizontal position of turning.

9 (a) and 9 (b) show the measurement results of the CO transformer 4 of the embodiment and the CO transformer 104 of the comparative example.
FIG. 7 is a characteristic diagram showing the relationship between horizontal positions α, β, γ, δ and temperatures for L, M, and H. In both cases (a) and (b), the temperature is higher at the position L than at the position E, the temperature is decreased at the position M, and the temperature is decreased to about 200 ° C. at the position L in common.

However, comparing the graphs of the position E, the temperature variations among the horizontal positions α, β, γ, δ are
While it is large in (b), it is small in (a). That is, in the CO transformer 104 of the comparative example, the position α near the gas inlet is about 250 ° C., the positions β and γ are about 290 ° C., and the position δ is about 320 ° C., which is considerably when the gas flows through the buffer layer. It shows that the temperature is rising.

On the other hand, in the CO transformer 4 of the embodiment, all the positions α, β, γ and δ are about 280 ° C. This indicates that the temperature of the gas is raised in the preheating layer, and the temperature of the gas hardly rises when flowing through the buffer layer. As described above, in the CO shift converter 4 of the example, it is understood that the temperature of the reformed gas entering the catalyst layer is made uniform as compared with the CO shift converter 104 of the comparative example.

(Other Matters) In the above embodiment, the reformed gas flows from the bottom to the top in the catalyst layer of the CO shift converter. The same can be done in the transformer. Further, in the above-described embodiment, an example in which the rectifying plate is used below the catalyst layer of the CO shift converter has been shown, but the present invention can be implemented without providing the rectifying plate.

Further, in the above embodiment, an example of the CO transformer having a double cylindrical tube structure is shown, but the CO transformer is not limited to the double cylindrical tube, but the CO transformer having a double cylindrical tube structure of an elliptic shape or a polygonal shape. The same can be done in a container. Further, in the above embodiment, an example of the reforming system in which the CO shift converter is provided around the reformer has been shown, but the present invention is applied to a fuel cell reactor having a similar double cylinder tube structure. can do.
For example, a desulfurizer having a double cylinder tube structure, which is provided on the outer circumference of a pipe through which a high-temperature fluid flows and has a desulfurization catalyst, can be carried out in the same manner, and the gas temperature entering the catalyst layer can be made uniform and the desulfurization can be performed. It is believed that an environment suitable for the reaction can be formed.

[0056]

As described above, according to the present invention, in a fuel cell reactor having a double cylinder tube structure provided around a high temperature body, the fuel cell is transmitted from the high temperature body to the buffer tank adjacent to the buffer tank. By providing a preheating tank that absorbs heat, by providing a gas communication port from the preheating tank to the buffer tank at a position approximately half a circumference apart from the gas inlet of the preheating tank in the annular space,
The temperature of the gas distributed to the catalyst layer can be made uniform, whereby the catalytic reaction can be performed well.

Further, such a fuel cell reactor can be constructed relatively easily by using a partition plate. In particular, the present invention, when applied to a CO shift converter for a fuel cell, has a large practical effect in that it can contribute to good catalytic reaction and reduction of carbon monoxide in the reformed gas.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a fuel gas reforming system including a CO transformer having a double cylindrical pipe structure according to a first embodiment.

2 is a cross-sectional view of a reformer and a CO shifter of the fuel gas reforming system shown in FIG.

FIG. 3 is a perspective view of the CO transformer shown in FIG.

FIG. 4 is a schematic cross-sectional view of the CO transformer shown in FIG. 1 in the vertical direction and the horizontal direction.

FIG. 5 is a schematic vertical and horizontal cross-sectional view of a CO transformer according to a second embodiment.

FIG. 6 is a schematic vertical and horizontal cross-sectional view of a CO transformer according to a third embodiment.

FIG. 7 is a vertical and horizontal schematic cross-sectional view of a CO transformer according to a fourth embodiment.

FIG. 8 is a schematic cross-sectional view of a conventional CO transformer in vertical and horizontal directions.

FIG. 9 is a characteristic diagram showing the results of experiments on the CO transformer of the example and the CO transformer of the comparative example.

[Explanation of symbols]

3 reformer 4 CO transformer 12 Combustion cylinder 13 burners 14 Fuel cell 31 Inner peripheral plate 32 outer peripheral plate 35 catalyst tank 36 Rectifier 38 Partition board 38a window 39 buffer tank 40 preheating tank

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takamasa Matsubayashi 2-5-5 Keihan Hondori, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd. (72) Inventor Yasuo Miyake 2-5 Keihan Hondori, Moriguchi City, Osaka Prefecture No. 5 within Sanyo Electric Co., Ltd. (56) Reference JP-A-7-240224 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 8/04 H01M 8/06

Claims (7)

(57) [Claims] 1. A buffer tank having a double-cylindrical structure provided around a high-temperature body and temporarily storing a catalyst layer and a gas to be supplied to the catalyst layer in an annular space between an inner tube and an outer tube. Are arranged so as to form a layer in the tube axis direction, and the gas is distributed to the catalyst layer while flowing in the buffer tank and flows in the catalyst layer in the tube axis direction, in the annular space. A preheating tank for absorbing heat transmitted from the high-temperature body to the buffer tank is provided adjacent to the buffer tank, and the preheating tank is provided at a portion separated from the gas inlet of the preheating tank in the annular space by approximately a half circumference. A fuel cell reactor characterized in that a gas communication port from the tank to the buffer tank is provided. 2. The preheating tank and the buffer tank are partitioned by a first partition plate made of a heat conductive member, and the gas communication port is opened in the first partition plate. The reactor for a fuel cell according to claim 1. 3. The fuel cell reactor according to claim 2, wherein the preheating tank is inserted between the buffer tank and the outer tube. 4. The reactor for a fuel cell according to claim 2, wherein the first partition plate has a flat plate shape, and the plate surface is provided substantially perpendicular to the tube axis direction. 5. The fuel cell reactor according to claim 2, wherein the first partition plate is a tube provided in the buffer tank. 6. The fuel cell reactor according to claim 1, wherein the preheating tank is inserted between the inner tube and the buffer tank. 7. The fuel according to claim 1, wherein a second partition plate having a plurality of gas distribution holes is inserted between the catalyst layer and the buffer tank. Battery reactor.