JPH09245825A - Fuel cell power generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell power generating device capable of shortening the time required to temperature rising of each reactor of a reforming device, and quickly, efficiently performing starting operation. SOLUTION: A reforming device for reforming raw fuel to reformed gas for supplying to a fuel electrode 1a of a fuel cell main body 1 has a desulfurization reactor 2, a reformer 3, a carbon monoxide reformer 4, and a nitrogen gas circulation circuit 12 in which a nitrogen gas supply circuit 11 and a circulation blower 5 are assembled for rising temperature. A temperature keeping heater 7 is arranged in the desulfurization reactor 2 and a temperature keeping heater 8 is arranged in the carbon monoxide reformer 4, and during stopping of power generating operation, the device is heated to the specified temperature and that temperature is kept.

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 structure of a reformer used in a fuel cell power generator that is frequently started and stopped.

[0002]

2. Description of the Related Art In a fuel cell power generator installed in an urban area or in the suburbs of the city, depending on its power demand,
It may be started and stopped frequently. In order to restart the fuel cell power generator in the stopped state, it is necessary to set each device constituting the device to a predetermined operating condition, and the raw fuel used to obtain the reformed gas to be supplied to the fuel cell main body is Also in the reformer, it is necessary to make each reactor a predetermined temperature condition.

FIG. 3 is a schematic diagram showing the basic construction of an example of a reformer equipped with a temperature raising means of a conventional fuel cell power generator. In the figure, 1 is a schematically shown fuel cell main body, 1a is a fuel electrode to which reformed gas is supplied, and 1b is an air electrode to which reaction air is supplied. The reforming device for reforming the introduced raw fuel into reformed gas includes a desulfurization reactor 2 for desulfurizing organic sulfur compounds contained in raw fuel by hydrogenation reaction and desulfurization reaction at 200 to 300 ° C, and a desulfurized raw material. 600 to 7 fuel
The reformer 3 that reforms the steam with a high hydrogen concentration by steam reforming at 50 ° C.
The reformer 3 includes a carbon monoxide shift converter 4 that reduces the carbon monoxide concentration at 0 to 300 ° C., and a burner 6 that is heated by combustion is incorporated in the reformer 3. Also,
A nitrogen gas supply circuit 11 and a nitrogen gas circulation circuit 12 incorporating the circulation blower 5 are incorporated for raising the temperature of the reformer. At the time of starting the apparatus, nitrogen gas is sent from the nitrogen gas supply circuit 11 to the reformer 3, and the nitrogen gas heated by the burner 6 to a high temperature is circulated by the circulation blower 5 via the nitrogen gas circulation circuit 12, By circulating and flowing through the desulfurization reactor 2, the reformer 3, and the carbon monoxide shift converter 4, each reactor is heated to a predetermined temperature.

FIG. 4 is a schematic diagram showing the basic structure of another example of the reformer equipped with the temperature raising means of the conventional fuel cell power generator. In the configuration shown in the figure, the desulfurization reactor 2 and the carbon monoxide shift converter 4 each have a built-in heater 10 for raising the temperature.
a and 10b are provided, the reformer 3 is heated by the combustion of the raw fuel in the burner 6, and the desulfurization reactor 2 and the carbon monoxide shift converter 4 have respective built-in heaters 10a, 10a, 10b. The temperature is raised to a predetermined temperature by 10b.

[0005]

As described above, in the conventional fuel cell power generator, a circulation circuit is installed to allow heated nitrogen gas to flow through each reactor, or a heater for heating is built in the reactor. As a result, the temperature of the reforming device is raised when the device is started. However, in the method in which the heated nitrogen gas is circulated in the circulation circuit to flow through each reactor to raise the temperature, the temperature of each reactor is sequentially raised to a predetermined temperature, so the temperature rise is completed. It takes a considerable amount of time to do so. Also, if a heater for heating is built into the reactor, each reactor can be heated individually, so the heating time is shortened, but it takes some time to heat the reactor that has become low temperature to a predetermined temperature. Is required, which impedes quick startup of the fuel cell power generator. Further, in a device such as a fuel cell power generation device arranged in an urban area or a suburb of the city, which is frequently started and stopped, there is a problem that a large amount of energy is required for heating.

The object of the present invention is to reduce the time required for the temperature raising operation of each reactor of the reforming apparatus, and further, in an apparatus in which starting and stopping are frequently performed, the amount of energy required for the temperature raising operation of each reactor. It is intended to provide a fuel cell power generation device in which the fuel consumption is reduced and a quick and efficient starting operation is possible.

[0007]

In order to achieve the above object, in the present invention, in a fuel cell power generator equipped with a reformer for reforming raw fuel and supplying it to the fuel cell body, Of the desulfurization reactor, reformer, and carbon monoxide shift converter that the system has as reactors, at least the desulfurization reactor and carbon monoxide shift converter are warmed and held while the generator is stopped A heat-retaining means is provided, and for example, a heater is wound around the outer periphery of the reaction vessel of these reactors.

According to the above, at least the desulfurization reactor and the carbon monoxide shifter are heated by the heat retaining means, for example, the heater wound around the outer periphery of the reaction vessel even when the power generation operation of the power generator is stopped. Since it is maintained at the predetermined temperature, it can be started immediately. Therefore, when the reformer is not provided with a heat retaining means, the reformer is heated by the combustion of the raw fuel, and for example, by circulating high temperature nitrogen gas to raise the temperature, the reformer can be operated in a short time. It can be moved to the startup state. Further, if the reformer is also provided with the heat retaining means, the reformer can be activated in an extremely short period of time.

Further, the heating amount per unit time required to maintain the temperature at a predetermined temperature is equivalent to the heating amount per unit time required for raising the temperature at the temperature. Since only a small amount is required, it is possible to reduce the total heating amount required when starting and stopping frequently.

[0010]

1 is a schematic diagram showing the basic structure of a reformer showing a first embodiment of a fuel cell power generator of the present invention. The feature of this configuration is that the nitrogen gas supply circuit 11 and the nitrogen gas circulation circuit 12 incorporating the circulation blower 5 are incorporated for raising the temperature as in the conventional example shown in FIG. In the carbon oxide transformer 4,
The heat-retaining heater 7 and the heat-retaining heater 8 for heating and holding the reactor while the power generation operation of the power generator is stopped are respectively wound around the outer circumference of the reaction vessel.

Therefore, the desulfurization reactor 2 and the carbon monoxide shift converter 4 are maintained at a predetermined temperature by the wound heat-retaining heaters 7 and 8 even during the stop of the power generation operation of the power generator, so that the reformer 3 By circulating the high temperature nitrogen gas heated by the combustion of the raw fuel in the burner 6 to raise the temperature, the reforming device can be brought into the starting state in a short time.

For a large-capacity fuel cell power generator in which a cycle of 5 days of operation and 2 days of suspension is repeated, a desulfurization reactor 2
And a device for raising the temperature of the carbon monoxide transformer 4 each time it is started, and a device for holding the carbon monoxide transformer 4 at a predetermined temperature by the heat insulation heaters 7 and 8 even when the operation is stopped as in the embodiment shown in FIG. Comparing and comparing the required energy associated with, the heat capacity required to raise the desulfurization reactor 2 and the carbon monoxide shift converter 4 from the stop temperature to a predetermined operating temperature is about 770 [kWh] in total. Therefore, the conventional device requires about 770 [kWh] of energy for each startup, and thus about 770 [kWh] of energy every week.

On the other hand, the heat flow rate required to maintain the desulfurization reactor 2 and the carbon monoxide shift converter 4 at a predetermined operating temperature is about 4.6 [kW]. Therefore, the energy for heat insulation required when the operation is stopped for 2 days (48 h) as above is about 220 [kWh], which is about 70% less energy than the conventional device. Will be done.

FIG. 2 shows a second embodiment of the fuel cell power generator according to the present invention.
It is a schematic diagram which shows the basic composition of the reforming apparatus which shows embodiment of this. The feature of this configuration is that not only the desulfurization reactor 2 and the carbon monoxide shift converter 4 but also the reformer 3 is provided with a heat-retaining heater 9 that heats and holds the reactor while the power generation operation of the power generator is stopped. It is wrapped around the outer circumference of the container. In this configuration,
Since the desulfurization reactor 2, the reformer 3, and the carbon monoxide shift converter 4 constituting the reformer are all heated and maintained at a predetermined operating temperature even during the stop of the power generation operation of the power generator. When starting the power generator, the reformer can be operated in an extremely short time, which is particularly effective for shortening the time required to start the power generator.

[0015]

As described above, according to the present invention, in a fuel cell power generator equipped with a reformer for reforming raw fuel and supplying it to the fuel cell body, desulfurization provided as a reactor in the reformer. Of the reactor, the reformer, and the carbon monoxide shift converter, at least the desulfurization reactor and the carbon monoxide shift converter should be equipped with heat retaining means for heating and holding the reactor while the power generation system is stopped. And, for example, since it was decided to wind a heater around the outer periphery of the reaction vessel of these reactors, the time required for the temperature raising operation of each reactor of the reformer is shortened, and further, the start and stop are frequently performed. In the device to be performed, the amount of energy required for the temperature raising operation of each reactor is reduced, and it is possible to obtain a fuel cell power generation device capable of quick and efficient start-up operation.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a basic configuration of a reformer showing a first embodiment of a fuel cell power generator of the present invention.

FIG. 2 is a schematic diagram showing a basic configuration of a reformer showing a second embodiment of a fuel cell power generator of the present invention.

FIG. 3 is a schematic diagram showing a basic configuration of an example of a reformer equipped with a temperature raising means of a conventional fuel cell power generator.

FIG. 4 is a schematic diagram showing the basic configuration of another example of a reformer equipped with a temperature raising means of a conventional fuel cell power generator.

[Explanation of symbols]

 1 Fuel Cell Main Body 1a Fuel Electrode 1b Air Electrode 2 Desulfurization Reactor 3 Reformer 4 Carbon Monoxide Shifter 5 Circulation Blower 6 Burner 7 Insulated Heater 8 Insulated Heater 9 Insulated Heater 10a Built-in Heater 10b Built-in Heater 11 Nitrogen Gas Supply Circuit 12 Nitrogen gas circulation circuit

Claims (2)

[Claims] 1. A fuel cell power generator including a reformer for reforming raw fuel and supplying the reformed raw fuel to a fuel cell main body. A desulfurization reactor, a reformer, and carbon monoxide shift converter provided as reactors in the reformer. Among the reactors, at least the desulfurization reactor and the carbon monoxide shift converter are provided with a heat-retaining means for heating and holding the reactor while power generation operation of the power generator is stopped, . 2. The fuel cell power generator according to claim 1, wherein the heat retaining means is a heater wound around an outer periphery of a reaction vessel of the reactor.