JP3263936B2 - Fuel cell generator - 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 power generator, and more particularly, to a fuel cell power generator using a molten carbonate fuel cell.

[0002]

2. Description of the Related Art Molten carbonate fuel cells have features that are not found in conventional power generation devices, such as high efficiency and little impact on the environment, and have attracted attention as power generation systems following hydro, thermal and nuclear power. Are being researched and developed in various countries around the world. In particular, in a power generation facility using a molten carbonate fuel cell using natural gas as a fuel, as shown in FIG. 2, a reformer 10 for reforming a fuel gas 1 such as natural gas into an anode gas 2 containing hydrogen, The fuel cell 20 generally includes a fuel cell 20 that generates electricity from the anode gas 2 and the cathode gas 3 containing oxygen. The anode gas produced by the reformer is supplied to the fuel cell, and most of the anode gas is generated in the fuel cell. After consuming 80%, for example, the combustion chamber C of the reformer 10 is used as the anode exhaust gas 4.
o. The fuel gas 1 is preheated by the fuel preheater 11 and enters the reforming chamber Re of the reformer. In the reformer, combustible components (hydrogen, carbon monoxide, methane, etc.) in the anode exhaust gas are burned in the combustion chamber, and the reforming chamber Re is heated by the high-temperature combustion gas to reform the fuel flowing inside. The combustion exhaust gas 5 that has exited the reforming chamber is heat-recovered by the air preheater 32, water is removed by the condenser 33 and the steam separator 34, and the air is pressurized by the turbine compressor (power recovery device 40). The mixed gas is heated by the air preheater 32 and merges with the cathode gas 3. As a result, carbon dioxide generated on the anode side of the battery enters the cathode gas 3 for the fuel cell via the combustion exhaust gas 5 and supplies carbon dioxide required for the cathode reaction of the fuel cell to the cathode side C. A part of the cathode gas 3 reacts in the fuel cell to become a cathode exhaust gas 7,
A part thereof is recirculated to the cathode inlet side, a part is supplied to the combustion chamber Co of the reformer 10 to burn the anode exhaust gas 4, and the remaining part is supplied to the power recovery device 40 to be recovered in pressure, and Is discharged. In the drawing, reference numeral 22 denotes a storage container of the fuel cell, and reference numeral 8 denotes a purge gas supplied to the storage container.

[0003]

In the fuel cell 20, a large amount of heat is generated by the reaction. Therefore, the conventional fuel cell power generator has a cathode gas circulation line 26 provided with a high-temperature blower 24 and a gas cooler (not shown), and cools a part of the cathode exhaust gas 7 and mixes it with the cathode gas 3. The temperature of the fuel cell 20 was maintained.

However, in such a conventional cooling means, since the calorific value of the fuel cell is large, the amount of the cathode exhaust gas 7 mixed into the cathode gas 3 becomes extremely large (for example, 10 times or more of the cathode gas required for the reaction). ), The pipe diameter of the cathode gas circulation line 26 becomes large,
However, there is a problem that the size becomes large and large power is required. On the other hand, the fuel gas 1 is preheated by the fuel preheater 11 and supplied to the reformer. However, the fuel preheater 11 also has a problem that it is large.

The present invention has been made to solve the above-mentioned problems. That is, the object of the present invention is:
An object of the present invention is to provide a fuel cell power generation device that can reduce the flow rate of cathode exhaust gas mixed into the cathode gas, thereby reducing the diameter of the piping of the cathode gas circulation line, reducing the size of the high-temperature blower, and reducing the power of the high-temperature blower. .

[0006]

According to Means for Solving the Problems] The present invention, cathode gas containing oxygen and anode gas (2) containing hydrogen
(3) a fuel cell (20) for generating electricity from a, the fuel cell
The anode exhaust gas (4) leaving (20) is converted to the cathode exhaust gas.
(7) is burned in some reformer for reforming fuel gas (1) by the heat in the anode gas (2) and (10), storage container for storing the fuel cell (20) (22) If, in order to indirectly heat the fuel <br/> material gas (1), wherein the fuel cell (2
0), the fuel cell is sandwiched between a plurality of cells constituting the fuel cell.
If a fuel gas flow path independent of (20) is provided,
The fuel preheating stored in the storage container (22)
, A fuel cell power generator comprising:

[0007]

According to the configuration of the present invention, the fuel preheater (2)
8) has an independent flow path and is the same as the fuel cell (20)
Since the storage is stored in the container (22), the reaction heat of the fuel cell (20), a fuel gas (1) can be indirectly heated. For this reason, the fuel preheater (2
8) is no longer required, the heat insulation and the number of pipes are reduced, and the whole can be made compact (compact). A part of the heat value of the fuel cell (20) is fuel gas.
Since it is removed by (1) , the amount of the cathode exhaust gas (7) mixed into the cathode gas (3) is reduced, whereby the pipe diameter of the cathode gas circulation line (26) is reduced, and the high-temperature blower (24) is removed. It is possible to reduce the size and power of the high-temperature blower (24) .

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. The same parts as those in FIG. 2 are denoted by the same reference numerals. FIG. 1 is an overall configuration diagram of a fuel cell power generator according to the present invention. Referring to FIG. 1, a fuel cell power generator according to the present invention includes a reformer 10 for reforming a fuel gas 1 into an anode gas 2 containing hydrogen and a fuel cell 20 for generating electricity from the anode gas 2 and the cathode gas 3 containing oxygen.
And an air preheater 32 that recovers heat from the combustion exhaust gas 5 that has exited the reformer 10. The reformer 10 includes the fuel cell 2
The anode gas (that is, the anode exhaust gas 4) that has exited 0 is burned by a part of the cathode gas (that is, the cathode exhaust gas 7) that has exited the fuel cell 20, and the heat is used to reform the fuel gas 1 into the anode gas 2. ing. Further, the fuel cell power generation device converts the combustion exhaust gas 5 exiting the reformer 10 into the fuel cell 2
Exhaust gas circulation line 3 for supplying cathode gas 3 entering 0
0, and a power recovery device 40 for compressing air in the remainder of the cathode exhaust gas 7 exiting the fuel cell 20 and supplying the compressed air to the exhaust gas circulation line 30.

The fuel cell 20 is stored in a storage container 22. Further, the fuel cell 20 according to the present invention has a built-in fuel preheater 28 for indirectly heating the fuel gas 1. The fuel preheater 28 is preferably sandwiched between a plurality of cells (not shown) constituting the fuel cell 20 and has a fuel gas flow path separate from the fuel cell 20. That is, although the fuel preheater 28 has an independent flow path, it is preferable that the fuel preheater 28 be substantially integrally formed, stored in the same storage container 22, and be kept warm.

With this configuration, the fuel gas can be indirectly heated by the reaction heat of the fuel cell. For this reason,
There is no need to provide a separate fuel preheater, the number of heat retention and piping is reduced, and the whole can be made compact (compact).

[0011]

As described above, the fuel cell power generator according to the present invention can indirectly heat the fuel gas by the reaction heat of the fuel cell, so that it is not necessary to provide a separate fuel preheater, and the heat retention can be maintained. And the number of pipes are reduced, so that the whole can be made small (compact). In addition, since a part of the calorific value of the fuel cell is removed by the fuel gas, the amount of the cathode exhaust gas mixed into the cathode gas decreases, This has excellent effects such as reducing the diameter of the piping of the cathode gas circulation line, reducing the size of the high-temperature blower, and reducing the power of the high-temperature blower.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a fuel cell power generator according to the present invention.

FIG. 2 is an overall configuration diagram of a conventional fuel cell power generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel gas 2 Anode gas 3 Cathode gas 4 Anode exhaust gas 5 Combustion exhaust gas 6 Air 7 Cathode exhaust gas 8 Purge gas 10 Reformer 11 Fuel preheater 20 Fuel cell 22 Container 24 High temperature blower 26 Cathode gas circulation line 28 Fuel preheater 30 Exhaust gas Circulation line 32 Air preheater 33 Condenser 34 Steam separator 40 Power recovery device Re Reforming chamber Co Combustion chamber A Anode side C Cathode side

Claims (1)

(57) [Claims] A fuel cell (2 ) that generates power from an anode gas (2) containing hydrogen and a cathode gas (3) containing oxygen.
0), is burned anode exhaust gas exiting the fuel cell (20) and (4) a part of the cathode exhaust gas (7), the fuel gas in the heat
Reformer (10) for reforming (1) to anode gas (2 )
When the fuel cell (20) storage container storing (22), in order to indirectly heat the fuel gas (1), is sandwiched between a plurality of cells of the fuel cell (20), said Burning
A fuel gas flow path independent of the fuel cell (20)
And the fuel stored in the storage container (22).
And a fuel pre-heater (28) .