JP2000281312A - Reforming device for fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reforming device for fuel cell capable of being miniaturized. SOLUTION: This reforming device 2 is provided with a cylindrical body 21 having a catalyst layer 37 packed with a reforming catalyst and a burner 22 for supplying the combustion gas to the cylindrical body 21 and the temp. of the catalyst layer 37 is elevated by the combustion gas from the burner 22, and fuel and steam are introduced into the catalyst layer 37 raised in the temp to generate hydrogen. In such a case, a steam generating chamber 42 for generating steam by heating water by the heat of the combustion gas is provided in the cylindrical body 21, and hydrogen is produced by introducing a mixture of fuel with water to the steam generating chamber 42, introducing the fuel and the steam out of the steam generating chamber 42 and introducing the mixture of the fuel and the steam to the catalyst layer 37.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reformer for a fuel cell which generates hydrogen by performing a steam reforming reaction of fuel and steam under a catalyst heated in a combustor.

[0002]

2. Description of the Related Art In general, there is known a fuel cell power generation system that generates hydrogen from a hydrocarbon fuel and generates power using the hydrogen and oxygen in the air. A reformer (reformer for a fuel cell) is used to convert fuel into hydrogen.

In FIG. 4, reference numeral 100 denotes a reformer of a conventional fuel cell system. The reformer 100 includes a reformer body 101 and a separate steam generator for supplying steam to the reformer body 101. Machine 102.

[0004] The reformer main body 101 has a cylindrical body 111,
At the end of the cylindrical body 111, a burner 112 is incorporated.
A blower 113 is provided on the cylindrical body 111. The combustion fuel gas pipe 116 and the fuel cell unreacted gas pipe 117 are connected to the burner 112, and the combustion fuel gas and the fuel cell unreacted gas are supplied to the burner 112 through each.

A heat exchange cylinder 114 having multiple partition walls is attached to the cylinder 111, and the heat exchange cylinder 114 has a quadruple cylinder wall structure. A reforming catalyst is provided between the second cylinder wall 122 and the third cylinder wall 123 and a catalyst layer 131 is provided between the second cylinder wall 122, the third cylinder wall 123, and the fourth cylinder wall 124. Is formed. Further, a flue gas pipe 125, a reformed gas pipe 126, and a mixed gas pipe 127 are connected to the heat exchange cylinder 114. The mixed gas pipe 127 is branched on the way into a fuel gas pipe 128 and a steam pipe 129, and the steam pipe 129 is connected to the steam generator 102. Reference numeral 130 denotes a water pipe that supplies water to the steam generator 102.

When the burner 112 is burning, the combustion gas generated by the combustion moves in the direction indicated by the dotted arrow. That is, the combustion gas moves inside the cylinder 111, between the cylinder 111 and the first cylinder wall 121, between the third cylinder wall 123 and the fourth cylinder wall 124, and inside the combustion exhaust gas pipe 125. The combustion gas is led to the outside.

A water pipe 130 is connected to the steam generator 102.
Is supplied to the steam pipe 129, and the steam is supplied to the steam pipe 129, and the steam and the fuel gas pipe 128 are supplied to the steam pipe 129.
From the fuel gas to form a mixed gas. The mixed gas of the fuel gas and the steam is supplied to the reformer 100 through the mixed gas pipe 127, and in the reformer 100, the mixed gas passes between the first cylinder wall 121 and the second cylinder wall 122. Here, the gas mixture is preheated by the combustion gas. When the preheated mixed gas passes through the catalyst layer 131, the mixed gas is heated to an appropriate reaction temperature (for example, 600 to 700 ° C.), steam reformed, and converted into a reformed gas containing hydrogen and carbon monoxide. Is done. Thereafter, the reformed gas is sent through a reformed gas pipe 126 to, for example, a carbon monoxide converter (not shown) that converts carbon monoxide into carbon dioxide.

[0008]

However, in the above-described reformer 100, a steam generator 102 separate from the reformer main body 101 is provided in order to supply steam to the reformer main body 101. Therefore, there is a problem that the reformer 100 becomes large.

An object of the present invention is to provide a fuel cell reforming apparatus which can solve the above-mentioned problems of the prior art and can be downsized.

[0010]

According to the first aspect of the present invention,
A cylinder having a catalyst layer filled with a reforming catalyst and a combustor for supplying combustion gas into the cylinder are provided, and the temperature of the catalyst layer is increased by the combustion gas from the combustor. In a reformer for a fuel cell for generating hydrogen by introducing fuel and steam to a catalyst layer, a steam generation chamber for generating steam by heating water by the heat of the combustion gas is provided in the cylinder. A mixture of fuel and water is led out of the steam generation chamber, and a mixture of the steam and fuel is led to the catalyst layer to generate hydrogen. It is a feature.

According to the present invention, since the steam generating chamber for heating the water by the heat of the combustion gas to generate the steam is provided in the cylinder, the fuel cell reforming apparatus can be reduced in size.

According to a second aspect of the present invention, there is provided a cylinder having a catalyst layer filled with a reforming catalyst, and a combustor for supplying a combustion gas into the cylinder, and the combustion gas from the combustor is used to generate the combustion gas. In a reformer for a fuel cell, which raises the temperature of a catalyst layer and guides fuel and water vapor to the heated catalyst layer to generate hydrogen, the heat of the combustion gas causes water to flow near a combustion gas supply section of the cylinder. Is provided with a steam generation chamber for generating steam by introducing the mixture of fuel and water into the steam generation chamber through an introduction pipe extending through the catalyst layer from the combustion gas discharge portion side of the cylindrical body. A mixture of fuel and steam is derived from the steam generation chamber, and the mixture of steam and fuel is guided to the catalyst layer to generate hydrogen.

According to the present invention, since the steam generating chamber for heating the water by the heat of the combustion gas to generate the steam is provided in the cylinder, the fuel cell reforming apparatus can be reduced in size.
Further, since the introduction pipe penetrates through the catalyst layer, the combustion gas and water in the introduction pipe are preheated, and the heat exchange rate is improved.

According to a third aspect of the present invention, in the second aspect of the present invention, a heat exchange chamber is formed at a combustion gas discharge portion of the cylindrical body, and the introduction pipe connects the catalyst layer through the heat exchange chamber. It is characterized by being penetrated.

According to the present invention, since the introduction pipe is passed through the heat exchange chamber of the combustion gas discharge section, the fuel gas and water in the introduction pipe are preheated, and the heat exchange rate between the combustion gas, the fuel gas and water is reduced. improves.

According to a fourth aspect of the present invention, in the second or third aspect of the present invention, a chamber partitioned by an upper partition and a lower partition is formed in the cylindrical body, and the catalyst layer and the steam generation are formed in this chamber. Providing a chamber, providing a plurality of tubes extending through the upper partition, the catalyst layer, and the lower partition, guiding the combustion gas supplied to the combustion gas supply unit to the combustion gas discharge unit through the plurality of tubes. It is characterized by the following.

According to the present invention, since the combustion gas is passed through the plurality of tubes penetrating the catalyst layer, the heat exchange rate between the combustion gas and the catalyst layer is improved, and the heat loss discharged to the outside is reduced. be able to.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a plurality of metal particles are provided in the steam generating chamber.

According to the present invention, the contact area between the metal particles and water is increased by the plurality of metal particles provided in the steam generation chamber, and the metal particles have a high thermal conductivity, so that the water is quickly raised. It can be heated and vaporized.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference symbol S indicates a fuel cell power generation system. In this fuel cell power generation system S, hydrogen is generated from a fuel gas such as natural gas, city gas, naphtha, etc. Is chemically reacted with oxygen to generate power. This fuel cell power generation system S
Desulfurization device 1 connected to pipe 91 to which fuel gas is supplied
A reformer (reformer for a fuel cell) 2 connected to the desulfurizer 1 via a pipe 92; and a carbon monoxide converter 3 connected to the reformer 2 via a pipe 93. A carbon monoxide removing device 4 connected to the carbon monoxide converting device 3 via a pipe 94; and a polymer electrolyte fuel cell main body 5 connected to the carbon monoxide removing device 4 via a pipe 95. And a water tank 6 connected to the fuel cell body 5 via a going water pipe 96a and a returning water pipe 96b.
The fuel cell body 5 includes a fuel electrode (anode) 5a, an air electrode (cathode) 5b, and a cooling unit 5c.

When the operation is started, the fuel gas is supplied to the pipe 91.
The sulfur component is removed from the fuel gas by the desulfurization device 1 through the desulfurization device 1. Water is mixed into the desulfurized fuel gas through a pipe 92 and sent to the reforming apparatus 2. In the reforming apparatus 2, the water mixed in the fuel gas is vaporized to generate steam. A reformed gas containing hydrogen and carbon monoxide is generated from the gas by a steam reforming reaction. The generated reformed gas is sent to the carbon monoxide shift device 3 through the pipe 93, and the carbon monoxide contained in the reformed gas is steam reformed in the carbon monoxide shift device 3 to be converted into carbon dioxide. The reformed gas has a carbon monoxide concentration of 1%
To a degree. Air is mixed into this reformed gas,
It is sent to the carbon monoxide removing device 4 through the pipe 94. In the carbon monoxide removing device 4, carbon monoxide contained in the reformed gas mixed with air is converted into carbon dioxide by a selective oxidation reaction, and the carbon monoxide concentration of the reformed gas is reduced to about 10 ppm. The reformed gas is sent to the fuel electrode 5a of the fuel cell body 5 through the pipe 95, and the hydrogen in the reformed gas introduced into the fuel electrode 5a and the air electrode 5b
An electrochemical reaction takes place between the oxygen introduced into the air and the oxygen in the air to generate electric power. Since the reaction in the fuel cell main body 5 is an exothermic reaction, the water in the water tank 6 goes to the cooling unit 5c through the water pipe 96a to cool the fuel cell main body 5,
The water heated by this cooling returns to the water tank 6 via the return water pipe 96b.

In FIG. 2, reference numeral 20 denotes a reformer main body of the above-described reforming apparatus 2. The reformer main body 20 has a cylindrical body 21, and a burner 22 is built in a lower end portion of the cylindrical body 21. Is done. The burner 22 is supplied with a combustion fuel gas pipe 23 for leading the combustion fuel gas to the burner 22 and a reformed gas (unreacted fuel cell gas) containing hydrogen not used in the fuel electrode 5 a of the fuel cell body 5. The unreacted gas pipe 24 to be guided is connected.

A combustion chamber 30a is provided below the cylindrical body 21.
Is formed at the upper part of the cylindrical body 21, and a combustion gas discharge part 31 having a heat exchange chamber 31a is formed between the combustion chamber 30a and the heat exchange chamber 31a. A cylindrical reaction chamber (chamber) 33 is formed, which is partitioned by 32a and the upper partition 32b. The reaction chamber 33 is provided with a plurality of tubes 34 extending from the lower partition 32a toward the upper partition 32b.
The internal space communicates with the combustion chamber 30a and the heat exchange chamber 31a. The outer space of the tube of the reaction chamber 33 is partitioned by a pair of lower porous partition plates (for example, punching metal) 35a having a plurality of holes and an upper porous partition plate 35b,
An introduction pipe 36a extending upward from the lower porous partition plate 35a penetrates the lower porous partition plate 35a and the upper partition 32b. The introduction tube 36a and the plurality of tubes 34 correspond to FIG.
As shown in the figure, they are juxtaposed at substantially equal intervals in the cylindrical body 21. Further, the lower perforated partition plate 35a and the upper perforated partition plate 3
The space between 5b is filled with the reforming catalyst to form the catalyst layer 37. A gas merging chamber 38 is formed between the upper porous partition plate 35b and the upper partition 32b, and this gas merging chamber 38 communicates with the catalyst layer 37 via a hole in the lower porous partition plate 35b. A steam generation chamber 42 containing a plurality of stainless steel grains (metal grains) 41 is formed between the lower porous partition plate 35a and the lower partition wall 32a, and the steam generation chamber 42 is formed on the catalyst layer 37 by the lower porous partition plate 35a. And the inside of the introduction pipe 36.

The introduction pipe 36 extends to a heat exchange chamber 31a formed in the combustion gas discharge section 31.
The introduction pipe 36b in 1a is spirally wound along the inner surface of the cylindrical body 21. The introduction pipe 36b is connected to the heat exchange chamber 3
1a is connected to the pipe 92 (FIG. 1) outside the reformer main body 21 through the cylindrical body 21.

At the time of operation of the fuel cell power generation system S, the combustion fuel gas is supplied to the burner 2 through the combustion fuel gas pipe 23.
2 and is burned by the burner 22. This combustion gas moves in the direction of the dotted arrow.

That is, the combustion gas is supplied to the combustion gas supply unit 3.
0 through the combustion chamber 30a and into the tube 34 of the reaction chamber 33, the steam generation chamber 42, and the steam generation chamber 42
After heating the plurality of stainless steel particles 41, the catalyst layer 37, the gas merging chamber 38, and the like in the inside, the heat is led to the heat exchange chamber 31a in the combustion gas discharge part 31, and the spiral inlet pipe 36b is heated to reform the reformer. It is guided outside the main body 20.

On the other hand, a mixture of fuel gas and water is introduced into the reformer main body 20 through the pipe 92 and moves in the direction of the solid arrow.

That is, the mixture of the fuel gas and water is guided into the spiral introduction pipe 36b, and the spiral introduction pipe 36b
b, preheated by the combustion gas flowing through the combustion chamber 31a,
The catalyst layer 37 heated by the combustion gas in the introduction pipe 36a of the reaction chamber 33 is further preheated. The preheated mixture is guided to the steam generation chamber 42, where the inner wall of the steam generation chamber 42 heated by the combustion gas and the steam generation chamber 4
The water contained in the mixture is vaporized by elevating the temperature by the stainless steel particles 41 stored in 2 to generate steam, and a mixed gas of the generated steam and fuel gas is heated (600 to 700 ° C.) by the combustion gas. Is introduced into the catalyst layer 37. A steam reforming reaction is performed under the catalyst of the catalyst layer 37, and is converted into a reformed gas containing hydrogen and carbon monoxide.
Since the mixed gas introduced into the catalyst layer 37 is sufficiently preheated, the temperature of the mixed gas inlet portion 37a of the catalyst layer 37 where the steam reforming reaction, which is an endothermic reaction, is actively performed is prevented, and the catalyst is cooled. A decrease in the steam reforming efficiency in the layer 37 can be prevented. Then, the reformed gas is guided to the pipe 93 through the gas merging chamber 38, and sent to the carbon monoxide converter 3 (FIG. 1) through the pipe 93.

According to the present embodiment, since the steam generation chamber 42 for generating water vapor by heating water by the heat of the combustion gas is provided in the cylinder 21, the size of the reformer 2 can be reduced. Further, since the introduction pipe 36a penetrates through the catalyst layer 37, the combustion gas and water in the introduction pipe 36a cause the high temperature catalyst layer 37
Thus, the heat exchange rate between the combustion gas, the fuel gas, and the water can be improved. Further, the spirally formed introduction pipe 36b is connected to the heat exchange chamber 31a of the combustion gas discharge section 31.
As a result, the fuel gas and water in the introduction pipe 36b are preheated, the heat exchange rate of the fuel gas and water with the combustion gas is improved, and the heat loss discharged to the outside can be reduced. Further, since the combustion gas is passed through the plurality of tubes 34 penetrating the catalyst layer 37, the heat exchange rate between the combustion gas and the catalyst layer 37 is improved, and the heat loss discharged to the outside can be reduced. Further, the stainless steel grains 41 provided in the steam generation chamber 42 are provided by the plurality of stainless steel grains 41.
The area of contact between water and water is increased and
Since water has a high thermal conductivity, water can be quickly heated and vaporized.

Although the present invention has been described based on the embodiments, it is apparent that the present invention is not limited to these embodiments. In the present embodiment, the plurality of stainless steel grains 41 are stored in the steam generation chamber 42.
For example, another metal protrusion group may be provided.

[0032]

According to the first aspect of the present invention, since the steam generating chamber for heating the water by the heat of the combustion gas to generate steam is provided in the cylinder, the fuel cell reforming apparatus can be downsized. It becomes possible.

According to the second aspect of the present invention, since the steam generating chamber for heating the water by the heat of the combustion gas to generate the steam is provided in the cylinder, the fuel cell reforming apparatus can be reduced in size. Become. Further, since the introduction pipe penetrates through the catalyst layer, the combustion gas and water in the introduction pipe are preheated by the high-temperature catalyst layer, and the heat exchange rate between the combustion gas, the fuel gas, and the water is improved.

According to the third aspect of the present invention, since the introduction pipe is passed through the heat exchange chamber of the combustion gas discharge section, the fuel gas and water in the introduction pipe are preheated, and the heat of the combustion gas, the fuel gas and the water is reduced. The exchange rate is improved.

According to the fourth aspect of the present invention, since the combustion gas is passed through the plurality of tubes penetrating the catalyst layer, the heat exchange rate between the combustion gas and the catalyst layer is improved, and the heat discharged to the outside is improved. Loss can be reduced.

According to the fifth aspect of the present invention, the contact area between the metal particles and water is increased by the plurality of metal particles provided in the steam generating chamber, and since the metal particles have a high thermal conductivity, water Can be quickly heated and vaporized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a fuel cell power generation system.

FIG. 2 is a sectional view showing the reforming apparatus according to the present embodiment.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view showing a conventional reformer.

[Explanation of symbols]

 S Fuel cell power generation system 2 Reformer (reformer for fuel cell) 20 Reformer main body 21 Cylindrical body (cylindrical body) 22 Burner (combustor) 30 Combustion gas supply unit 30a Combustion chamber 31 Combustion gas discharge unit 31a Heat Exchange chamber 32a Lower partition 32b Upper partition 34 Tube 37 Catalyst layer 42 Steam generation chamber

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Osamu Tajima 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Akira Fujio 2-5-5 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. F term (reference) 4G040 EA03 EA06 EB14 EB23 EB44 5H027 AA02 BA01 BA09 BA16 BA17

Claims (5)

[Claims] 1. A cylinder having a catalyst layer filled with a reforming catalyst, and a combustor for supplying combustion gas into the cylinder, wherein the temperature of the catalyst layer is increased by the combustion gas from the combustor. In the fuel cell reformer for generating hydrogen by introducing fuel and steam to the heated catalyst layer, a steam generation chamber is provided in the cylinder to heat water by heat of the combustion gas to generate steam. Guiding the mixture of the fuel and water to the steam generation chamber, deriving a mixture of the fuel and steam from the steam generation chamber, and guiding the mixture of the steam and the fuel to the catalyst layer to generate hydrogen. A reformer for a fuel cell, wherein the reformer has a configuration. 2. A cylinder having a catalyst layer filled with a reforming catalyst, and a combustor for supplying a combustion gas into the cylinder, wherein the temperature of the catalyst layer is raised by the combustion gas from the combustor. In a fuel cell reformer for generating hydrogen by introducing fuel and water vapor to the heated catalyst layer, the water is heated by the heat of the combustion gas to generate water vapor near the combustion gas supply section of the cylinder. A steam generation chamber to be generated is provided, and the mixture of the fuel and water is introduced into the steam generation chamber through an introduction pipe extending through the catalyst layer from the combustion gas discharge portion side of the cylindrical body. A reformer for a fuel cell, wherein a mixture of fuel and steam is derived, and the mixture of steam and fuel is guided to the catalyst layer to generate hydrogen. 3. The fuel cell according to claim 2, wherein a heat exchange chamber is formed in a combustion gas discharge portion of the cylindrical body, and the introduction pipe penetrates the catalyst layer through the heat exchange chamber. For reformer. 4. A chamber partitioned by an upper partition and a lower partition is formed in the cylindrical body, and the chamber is provided with the catalyst layer and the steam generation chamber, and penetrates the upper partition, the catalyst layer, and the lower partition. 4. A reformer for a fuel cell according to claim 2 or 3, wherein a plurality of tubes extending to the combustion gas supply section are provided, and the combustion gas supplied to the combustion gas supply section is guided to the combustion gas discharge section through the plurality of tubes. apparatus. 5. The reformer for a fuel cell according to claim 1, wherein a plurality of metal particles are provided in the steam generation chamber.