JP2003229149A - Fuel cell generating system and fuel cell generating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell generating system and a generating method in which a purge process of an atmosphere in the fuel gas passage can be realized without using nitrogen before the generation start or after the generation stop, and inflow of high concentration carbon monoxide into the fuel cell can be prevented at the time of the starting of the system operation. <P>SOLUTION: The generating system comprises a fuel gas generating means for generating a fuel gas rich in hydrogen from a raw material made mainly of a compound containing carbon and hydrogen, a raw material supply source for supplying the raw material to the fuel gas generating means, a fuel gas supply means for supplying the fuel gas from the fuel gas generating means to the fuel gas passage that includes a fuel pole of the fuel cell, and a bypass means for injecting the raw material from the raw material supply source into the fuel gas passage of the fuel cell by bypassing the fuel gas generating means. The raw material is injected into the fuel gas passage of the fuel cell through the above bypass means as a substitution gas at least either before the generation start or after generation stop of the fuel cell. <P>COPYRIGHT: (C)2003,JPO

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 generation system and a power generation method for generating power using a fuel cell.

[0002]

2. Description of the Related Art A conventional fuel cell power generation system or power generation method has a configuration as shown in FIG. 20 as disclosed in Japanese Patent Laid-Open No. 3-257762. That is, a fuel cell 1, a desulfurizer 3 that removes a sulfur component from a raw material gas such as natural gas, a reaction portion 2a of a fuel gas generation portion 2 that generates a hydrogen-rich gas from the desulfurized raw material gas,
A burner 2b as a heating means for heating the reaction part 2a,
A nitrogen facility 5 connected by a nitrogen supply pipe 7 having a shutoff valve 6 is provided upstream of the fuel gas generation unit 2, and the fuel generated in the fuel gas generation unit 2 is supplied to a fuel cell through a reformed gas supply pipe 8. The fuel was supplied to the fuel electrode 1a of No. 1 and the remaining fuel was supplied to the burner 2b via the exhaust hydrogen connecting pipe 9. Air is supplied to the oxidizer electrode of the fuel cell 1 by the blower 4.

In a general fuel cell power generation system or power generation method, when the power generation operation is stopped, the supply of the raw material gas is first stopped. The phenomenon that occurs at this time will be described with reference to FIG. 20. In the flow path from the fuel gas generation unit 2 to the reformed gas supply pipe 8 and the fuel cell 1 to the exhaust hydrogen connecting pipe 9, especially from the fuel electrode 1a to drain water. The hydrogen-rich gas will stay in the flow path to the element connecting pipe 9. Therefore, when air flows into the hydrogen-rich gas passage from the burner 2b released to the atmosphere by natural convection, hydrogen may explode.

Therefore, in the fuel cell power generation system or power generation method disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-257762 and shown in FIG.
And a nitrogen gas as an inert gas from the nitrogen equipment 5 through the nitrogen supply pipe 7, and a flow path from the fuel gas generation unit 2 to the reformed gas supply pipe 8 and the fuel cell 1 to the exhaust hydrogen connecting pipe 9. In particular, the hydrogen rich gas is injected into the fuel gas flow passage from the fuel electrode 1a to the exhaust hydrogen connecting pipe 9, and the hydrogen rich gas is discharged from the fuel gas flow passage by the nitrogen gas, that is, purged, and the purged hydrogen rich gas is burned. It was designed to burn in 2b. As described above, in the conventional fuel cell power generation system, hydrogen is prevented from exploding in the purging process of the hydrogen-rich gas by the nitrogen gas from the fuel gas passage, and safety is ensured.

[0005]

[Patent Document 1] JP-A-3-257762

[0006]

In the conventional fuel cell power generation system or power generation method, it is necessary to provide nitrogen equipment such as a nitrogen cylinder for the above-mentioned nitrogen gas purging step. When used as a power source for an electric vehicle, there is a problem that it requires a large space and further requires an initial cost. Also, it is necessary to regularly replace and refill the nitrogen cylinder,
There is a problem that running costs are high.

Further, at the time of starting the fuel gas producing section, the produced fuel gas contains a high concentration of carbon monoxide. If the fuel cell is a solid polymer electrolyte fuel cell, it poisons the catalyst at the anode of the fuel cell. However, in the conventional fuel cell power generation system or power generation method, the fuel gas containing a high concentration of carbon monoxide at the time of startup is supplied to the fuel cell, which causes performance deterioration due to catalyst poisoning of the fuel cell fuel electrode. .

The present invention takes into consideration the problems of the conventional fuel cell power generation system or power generation method as described above,
An object of the present invention is to provide a fuel cell power generation system and a power generation method capable of purging hydrogen-rich gas from a fuel gas passage without using nitrogen before the start of power generation and after the end of power generation. Another object of the present invention is to provide a fuel cell power generation system and a power generation method capable of preventing a high concentration of carbon monoxide from flowing into a fuel cell at the time of starting the system operation.

[0009]

A fuel cell power generation system based on the first method of the present invention includes a fuel cell having a fuel electrode and an oxidant electrode, and a fuel gas flow path of the fuel cell including the fuel electrode. Fuel gas supply means for supplying fuel gas,
An oxidant gas supply means for supplying an oxidant gas to an oxidant gas flow path of the fuel cell including the oxidant electrode, and a replacement gas containing a compound containing carbon and hydrogen as a main component to the fuel gas flow path. Of the fuel gas flow path by injecting the replacement gas into the fuel gas flow by the replacement gas supply means before and / or after power generation of the fuel cell is started. The atmosphere is replaced by the replacement gas.

The fuel cell power generation system according to the first method of the present invention further comprises air supply means for supplying air to the fuel gas passage to replace the atmosphere in the fuel gas passage with air. After the power generation is completed, the replacement gas supply unit injects the replacement gas into the fuel gas flow path to replace the atmosphere in the fuel gas flow path with the replacement gas, and then the air supply unit supplies the fuel gas flow. It is preferable to inject the air into the passage to replace the atmosphere in the fuel gas passage with the air.

In the fuel cell power generation method based on the first method of the present invention, a fuel gas is provided in the fuel gas passage of a fuel cell having a fuel gas passage including a fuel electrode and an oxidant gas passage including an oxidant electrode. In a fuel gas supply step for supplying the fuel gas and in at least one of before and after the power generation of the fuel cell, the fuel gas flow channel is filled with a replacement gas containing a compound containing carbon and hydrogen as a main component, and the fuel is supplied. A first replacement step of replacing the atmosphere in the gas flow path with the replacement gas. A fuel cell power generation method based on the first method of the present invention comprises:
The method may further include a second replacing step of performing the first replacing step after the power generation is completed and then injecting air into the fuel gas passage to replace the atmosphere in the fuel gas passage with the air. preferable.

A fuel cell power generation system based on the second method of the present invention produces a hydrogen-rich fuel gas from a fuel cell having a fuel electrode and an oxidizer electrode and a raw material containing a compound containing carbon and hydrogen as main components. Fuel gas generating means, a raw material supply source for supplying the raw material to the fuel gas generating means, and a fuel for supplying the fuel gas from the fuel gas generating means to the fuel gas flow path of the fuel cell including the fuel electrode. A gas supply means and a bypass means for bypassing the fuel gas generation means from the raw material supply source and injecting the raw material into the fuel gas passage as a raw material gas, before starting power generation of the fuel cell and ending power generation. In at least one of the latter, the raw material gas is injected into the fuel gas passage through the bypass means to replace the atmosphere of the fuel gas passage with the raw material gas. Configured so that.

The second method of the present invention further comprises air supply means for supplying air to the fuel gas passage to replace the atmosphere in the fuel gas passage with the air, and after the power generation is completed. Injecting the raw material gas into the fuel gas passage by the bypass means to replace the atmosphere in the fuel gas passage with the raw material gas, and then injecting the air into the fuel gas passage by the air supply means do it,
It is preferable that the atmosphere of the fuel gas channel is replaced with the air.

In the fuel cell power generation method based on the second method of the present invention, a fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and a fuel containing a fuel electrode A fuel gas supply step of supplying the fuel gas to the fuel gas flow path of a fuel cell having a gas flow path and an oxidant gas flow path including an oxidant electrode; A first replacement step of supplying the material gas to replace the atmosphere of the fuel gas flow path, wherein the first replacement step is performed before and / or after power generation of the fuel cell is started. . In the power generation method of the second method of the present invention, after performing the first replacement step after the power generation is completed,
It is preferable to include a second replacement step of injecting air into the fuel gas passage to replace the atmosphere in the fuel gas passage with the air.

A fuel cell power generation system based on the third method of the present invention produces a hydrogen-rich fuel gas from a fuel cell having a fuel electrode and an oxidizer electrode and a raw material containing a compound containing carbon and hydrogen as main components. Fuel gas generating means, a raw material supply source for supplying the raw material to the fuel gas generating means, and a fuel for supplying the fuel gas from the fuel gas generating means to the fuel gas flow path of the fuel cell including the fuel electrode. A gas supply unit; and a replacement gas supply unit for injecting a replacement gas containing a compound containing carbon and hydrogen as a main component into the fuel gas passage to replace the atmosphere of the fuel gas passage with the replacement gas. A fuel cell power generation system,
Arbitrary time period from the start of the fuel cell power generation system to the start of power generation, the substitution gas supply unit injects the substitution gas into the fuel gas passage to create the atmosphere of the fuel gas passage. It is replaced with the replacement gas.

In the fuel cell power generation method based on the third method of the present invention, a fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and a fuel containing a fuel electrode A fuel gas supplying step of supplying the fuel gas to the fuel gas channel of a fuel cell having an oxidant gas channel including a gas channel and an oxidant electrode; and a compound containing carbon and hydrogen in the fuel gas channel. A first replacement step of injecting a replacement gas as a main component to replace the atmosphere of the fuel gas flow path with the replacement gas, any time between after the start of the fuel cell and before the start of power generation. During the time period, the first replacement step is performed.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A fuel cell power generation system based on the first mode of the present invention is a fuel cell having a fuel electrode and an oxidant electrode, and a fuel gas is provided in a fuel gas flow path of the fuel cell including the fuel electrode. A fuel gas supply means for supplying an oxidant gas to the oxidant gas flow path of the fuel cell including the oxidant electrode, and a compound containing carbon and hydrogen in the fuel gas flow path. A replacement gas supply means for supplying a replacement gas containing as a main component, the replacement gas supply means for supplying the replacement gas to the fuel gas flow path before and / or after completion of power generation of the fuel cell. And the atmosphere of the fuel gas passage is replaced with the replacement gas.

Similarly, in the fuel cell power generation method based on the first method of the present invention, the fuel gas flow path of the fuel cell has a fuel gas flow path including a fuel electrode and an oxidant gas flow path including an oxidant electrode. A fuel gas supply step of supplying a fuel gas to the fuel cell and at least one of before and after power generation of the fuel cell is started, and a replacement gas containing a compound containing carbon and hydrogen as a main component is injected into the fuel gas flow path. And a first replacement step of replacing the atmosphere of the fuel gas passage with the replacement gas. In these power generation systems and power generation methods, the atmosphere of the fuel gas flow path including the fuel electrode of the fuel cell is purged with a replacement gas before and / or after the power generation of the fuel cell is finished, so that the fuel cell remains inside the fuel cell. There is no danger of the fuel gas coming into contact with the air, and there is no risk of the fuel gas exploding inside the fuel cell.

In a preferred aspect of the power generation system of the first system of the present invention, air supply means for supplying air to the fuel gas passage to replace the atmosphere in the fuel gas passage with air is further provided. After the power generation is completed, the replacement gas supply unit injects the replacement gas into the fuel gas flow path to replace the atmosphere in the fuel gas flow path with the replacement gas, and then the air supply unit supplies the fuel gas. The air is injected into the flow passage to replace the atmosphere in the fuel gas flow passage with the air.

Similarly, in a preferred mode of the power generation method of the first method of the present invention, after the first replacement step is carried out after the power generation is completed, air is injected into the fuel gas flow path to carry out the fuel injection. A second replacement step of replacing the atmosphere in the gas flow path with the air is included. In these aspects of the power generation system and the power generation method, after the atmosphere of the fuel gas flow path including the fuel electrode is purged with the replacement gas, the replacement gas is further purged with air. Can be held in a safe state. Further, since the fuel gas and the air do not come into contact with each other, there is no possibility of explosion inside the fuel cell.

In another preferred aspect of the power generation system of the first mode of the present invention, the fuel gas supply means is a fuel for producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components. The fuel gas generation unit includes a gas generation unit and a raw material supply source that supplies the raw material to the fuel gas generation unit, until the substitution gas supply unit completes the injection of the substitution gas into the fuel gas flow path. Means perform the fuel gas production.

Similarly, in another preferred embodiment of the power generation method of the first method of the present invention, the fuel gas supply step comprises producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components. A fuel gas generation step of generating the fuel gas, and the fuel gas is generated in the fuel gas generation step until the injection of the substitution gas into the fuel gas flow path in the first substitution step is completed. According to these aspects of the power generation system and the power generation method, stable combustion in the burner that heats the reaction part in the fuel gas generation means, that is, until the replacement of the atmosphere of the fuel gas flow path including the fuel electrode with the replacement gas is completed, that is, A stable fuel gas production process can be realized.

In still another preferred embodiment of the power generation system or the power generation method of the first mode of the present invention, a fuel generating means for generating hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components is provided. A steam supply means for replacing with steam or a replacement step with steam (third replacement step) is provided. After the power generation of the fuel cell is completed, the replacement gas is injected into the fuel gas flow path including the fuel electrode of the fuel cell by the replacement gas supply means to replace the fuel gas flow path with the replacement gas, and then the fuel gas generation means The fuel gas generation is stopped and the water vapor supply means injects water vapor into the fuel gas generation means. Alternatively, after the power generation of the fuel cell is finished, the fuel gas generation of the fuel gas generation means is stopped, the steam is injected into the fuel gas generation means by the steam supply means, and the replacement gas is supplied to the fuel gas by the replacement gas supply means. Inject into the fuel gas flow path. That is, the fuel gas generation is stopped, and the third replacement step and the first replacement step are performed.

According to these power generation systems or power generation methods, the atmosphere inside the fuel gas generating means is purged with water vapor, so that the combustible gas hardly remains in the fuel gas passage. By injecting water vapor into the fuel gas generation means, cooling of the fuel gas generation means is promoted, and the time until the end of operation can be shortened. The time for replacement can be shortened by independently injecting water vapor into the fuel gas generating means and injecting replacement gas into the fuel gas flow path including the fuel electrode of the fuel cell.

In another preferred embodiment of the first mode of the present invention, air is supplied to the fuel gas flow passage including the fuel electrode of the fuel cell and the fuel gas generating means, and the atmosphere of the fuel gas flow passage and the atmosphere An air supply unit for replacing the atmosphere inside the fuel gas generation unit with air is provided, and the replacement gas is supplied to the fuel gas flow channel of the fuel gas generation unit and steam is injected into the fuel gas generation unit. Air is injected into both the inside of the gas generating means by the air supply means. This makes it possible to replace the atmosphere in both the fuel gas passage and the inside of the fuel gas generation means with air.

Here, the air injection by the air supply means is performed in series from the fuel gas generation means to the fuel gas passage of the fuel cell. Alternatively, the air injection by the air supply means is performed in parallel with the fuel gas generation means and the fuel gas flow path of the fuel cell. According to the former, the air can be replaced from the upstream side of the fuel gas flow path to the downstream side along the flow path. Also, according to the latter, the entire fuel gas flow path can be replaced with air in a short time.

Further, in another aspect of the first system of the present invention, the fuel gas generating means includes a shift section provided with a shift catalyst body containing at least a noble metal and a metal oxide as constituent materials, and the shift section. A hydrogen gas supply unit for supplying hydrogen gas containing at least carbon monoxide and water vapor as secondary components is provided. As a result, the oxidation resistance inside the fuel gas generating means is enhanced, so that even if air is injected into the inside, the problem of the oxidation is unlikely to occur.

A fuel cell power generation system based on the second method of the present invention produces a hydrogen-rich fuel gas from a fuel cell having a fuel electrode and an oxidizer electrode, and a raw material containing a compound containing carbon and hydrogen as main components. Fuel gas generating means, a raw material supply source for supplying the raw material to the fuel gas generating means, and a fuel for supplying the fuel gas from the fuel gas generating means to the fuel gas flow path of the fuel cell including the fuel electrode. A gas supply means and a bypass means for bypassing the fuel gas generation means from the raw material supply source and injecting the raw material into the fuel gas passage as a raw material gas, before starting power generation of the fuel cell and ending power generation. In at least one of the latter, the raw material gas is injected into the fuel gas passage through the bypass means to replace the atmosphere of the fuel gas passage with the raw material gas. Configured so that.

Similarly, the fuel cell power generation method based on the second method of the present invention comprises a fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material whose main component is a compound containing carbon and hydrogen, and a fuel electrode. A fuel gas supply step of supplying the fuel gas to the fuel gas flow path of a fuel cell having a fuel gas flow path including an oxidant electrode and an oxidant electrode flow path including an oxidant electrode,
A first replacement step of supplying the raw material as a raw material gas directly to the fuel gas flow path to replace the atmosphere of the fuel gas flow path with the raw material gas, before starting power generation of the fuel cell and after ending power generation. In at least one of the above, the first replacement step is performed.

In these power generation systems and power generation methods, the atmosphere of the fuel gas flow path including the fuel electrode of the fuel cell is purged with the raw material gas before and / or after the power generation of the fuel cell is started, thereby purifying the fuel cell. There is no danger that the fuel gas remaining inside the fuel cell will come into contact with the air, and there is no risk that the fuel gas will explode inside the fuel cell. Further, since the gas for purging the atmosphere requiring purging is supplied from the same supply source as the raw material, a simple and efficient system can be obtained.

In a preferred aspect of the second type power generation system of the present invention, air supply means for supplying air to the fuel gas passage to replace the atmosphere in the fuel gas passage with the air is further provided. After the power generation, the bypass means injects the raw material gas into the fuel gas passage to replace the atmosphere in the fuel gas passage with the raw material gas, and then the air supply means supplies the fuel gas flow. The air is injected into the passage to replace the atmosphere in the fuel gas passage with the air.

Similarly, in a preferred mode of the fuel cell power generation method of the second method of the present invention, after the first replacement step is carried out after the power generation is completed, air is injected into the fuel gas flow path to carry out the above process. A second replacement step of replacing the atmosphere in the fuel gas passage with the air is included. According to these aspects of the power generation system or the power generation method, after the atmosphere of the fuel gas flow path including the fuel electrode is purged with the raw material gas, the raw material gas is further purged with air.
Fuel cells can be kept in a very safe condition. Further, since the fuel gas and the air do not come into contact with each other, there is no possibility of explosion inside the fuel cell.

In another preferred aspect of the power generation system of the second method of the present invention, until the injection of the raw material gas into the fuel gas flow path by the bypass means is completed,
The fuel gas generation means performs the fuel gas generation. Similarly, in another preferred aspect of the power generation method of the second method of the present invention, in the fuel gas production step, the injection of the raw material gas into the fuel gas flow path in the first replacement step is completed. Fuel gas is produced. According to these aspects of the power generation system or the power generation method, stable combustion in the burner that heats the reaction portion in the fuel gas generation means, that is, stable operation, until the replacement of the fuel gas passage including the fuel electrode with the replacement gas is completed. A fuel gas production process can be realized.

In still another preferred aspect of the power generation system of the second type of the present invention, steam supply means for supplying steam to the fuel gas generation means to replace the atmosphere inside the fuel gas generation means with the steam. Further comprising, after the power generation is completed, the bypass gas is used to inject the raw material gas into the fuel gas passage to replace the atmosphere in the fuel gas passage with the raw material gas. While stopping the production of the fuel gas,
The steam supply unit injects the steam into the fuel gas generation unit to replace the atmosphere inside the fuel gas generation unit with the steam.

Alternatively, it further comprises steam supply means for replacing the atmosphere inside the fuel gas generation means with steam, and after the power generation is completed, the fuel gas generation of the fuel gas generation means is stopped and the steam supply means is used to Water vapor is injected into the fuel gas generating means, and the raw material gas is injected into the fuel gas passage by the bypass means to replace the atmosphere in the fuel gas passage with the raw material gas.

Similarly, in still another preferred aspect of the power generation method of the second method of the present invention, the fuel gas generation in the fuel gas generation step is performed using a fuel gas generation means, and the fuel gas generation is performed. Further comprising a third replacing step of supplying water vapor to the means to replace the atmosphere inside the fuel gas producing means with the water vapor, and stopping the fuel gas producing step by the fuel gas producing means after the power generation is completed. The third replacement step and the first replacement step are performed.

According to these aspects of the power generation system or the power generation method, the combustible gas does not substantially remain in the fuel gas passage by purging the internal atmosphere of the fuel gas generation means with steam. By injecting water vapor into the fuel gas generating means, cooling of the fuel gas generating means is promoted and the time until the end of operation can be shortened.
By injecting water vapor into the fuel gas generating means and injecting the replacement gas into the fuel gas passage including the fuel electrode of the fuel cell independently, the time for replacement can be shortened.

[0038] In still another preferred aspect of the second system of the present invention, air is supplied to the fuel gas flow passage and the fuel gas generating means, and the atmosphere of the fuel gas flow passage and the fuel gas are supplied. Further comprising air supply means for replacing the atmosphere inside the generating means with the air, and supplying the source gas to the fuel gas passage to replace the atmosphere in the fuel gas passage with the source gas. Supplying the air to both the fuel gas flow path and the inside of the fuel gas generation means after injecting the water vapor into the fuel gas generation means and replacing the atmosphere inside the fuel gas generation means with the water vapor Means for injecting the air to replace the atmosphere in the fuel gas flow passage with the atmosphere in the fuel gas generating means.

As a result, the entire raw material and fuel gas passages in the system can be replaced with air. Here, in a preferred mode of injecting air by the air supply means, it is performed in series from the fuel gas generation means to the fuel gas flow path. Alternatively, in another preferable mode of injecting air by the air supply means, it is performed in parallel with the fuel gas generation means and the fuel gas flow path. According to the former, the air can be replaced from the upstream side of the fuel gas flow path to the downstream side along the flow path. Also, according to the latter, the entire fuel gas flow path can be replaced with air in a short time.

In another aspect of the second system of the present invention, the fuel gas generating means comprises a shift conversion section provided with a shift catalyst body containing at least a noble metal and a metal oxide as constituent materials,
The shift section is provided with a hydrogen gas supply section for supplying hydrogen gas containing at least carbon monoxide and water vapor as secondary components. As a result, the oxidation resistance inside the fuel gas generating means is enhanced, so that even if air is injected into the inside, the problem of the oxidation is unlikely to occur.

A fuel cell power generation system based on the third method of the present invention produces a hydrogen-rich fuel gas from a fuel cell having a fuel electrode and an oxidant electrode and a raw material containing a compound containing carbon and hydrogen as main components. Fuel gas generating means, a raw material supply source for supplying the raw material to the fuel gas generating means, and a fuel for supplying the fuel gas from the fuel gas generating means to the fuel gas flow path of the fuel cell including the fuel electrode. A gas supply unit; and a replacement gas supply unit for injecting a replacement gas containing a compound containing carbon and hydrogen as a main component into the fuel gas passage to replace the atmosphere of the fuel gas passage with the replacement gas. A fuel cell power generation system,
Arbitrary time period from the start of the fuel cell power generation system to the start of power generation, the substitution gas supply unit injects the substitution gas into the fuel gas passage to create the atmosphere of the fuel gas passage. It is replaced with the replacement gas.

Further, in a preferred aspect of the third system of the present invention, the replacement gas supply means bypasses the fuel gas generation means from the raw material supply source and replaces the raw material with the fuel gas flow path. It is a means of injecting as a gas. Similarly, in the fuel cell power generation method based on the third method of the present invention, a fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and a fuel containing a fuel electrode A fuel gas supplying step of supplying the fuel gas to the fuel gas channel of a fuel cell having an oxidant gas channel including a gas channel and an oxidant electrode; and a compound containing carbon and hydrogen in the fuel gas channel. A first replacement step of injecting a replacement gas as a main component to replace the atmosphere of the fuel gas flow path with the replacement gas, any time between after the start of the fuel cell and before the start of power generation. During the time period, the first replacement step is performed.

These power generation systems or their modes,
Alternatively, according to the power generation method, there is no danger that the fuel gas remaining inside the fuel cell will come into contact with air, and there is no risk that the fuel gas will explode inside the fuel cell. It is possible to prevent the problem that the fuel gas containing a high concentration of carbon monoxide flows into the fuel gas flow path including the fuel electrode due to diffusion and the fuel electrode is poisoned at the initial stage of the operation of the fuel gas generation means.

According to a further aspect of each system and each aspect of the present invention described above, a carbon monoxide concentration detecting means for detecting the carbon monoxide concentration contained in the fuel gas produced in the fuel gas producing means is further provided. Then, the replacement gas or the source gas as the replacement gas is injected into the fuel gas flow path including the fuel electrode until the detection value detected by the carbon monoxide concentration detection means falls below a predetermined value. Thus, it is possible to prevent the problem that the fuel gas containing a high concentration of carbon monoxide flows into the fuel gas flow path by diffusion and poisons the fuel electrode at the initial operation of the fuel gas generation means.

Further, in each system and each embodiment of the present invention, the preferred replacement gas does not contain a sulfur component. As a result, poisoning of the fuel electrode catalyst can be prevented. Further, in each mode and each aspect of the present invention, a preferable raw material supplied from the raw material supply source is a gas obtained by removing the sulfur component contained in the city gas. This allows
The raw material can be easily used, and the poisoning of the fuel electrode catalyst can be prevented. Embodiments of the present invention will be described below with reference to the drawings.

<< Embodiment 1 >> FIG. 1 shows the configuration of a fuel cell power generation system according to Embodiment 1 of the present invention. The fuel cell power generation system according to the present embodiment includes a fuel cell 11,
A fuel supply unit for supplying a fuel gas to the fuel electrode 11a of the fuel cell, an oxidant gas supply unit for supplying an oxidant gas to the oxidant electrode of the fuel cell, and a desulfurization gas obtained by removing sulfur components from city gas as a replacement gas. A desulfurization gas supply pipe 12 for supplying the fuel gas supply pipe 10 is provided. The replacement gas contains a compound containing carbon and hydrogen such as hydrocarbon as a main component.

Further, the desulfurization gas supply pipe 12 is provided with a desulfurizer 13 for removing a sulfur component from a raw material of a replacement gas containing a sulfur component such as city gas, and an opening / closing valve 14 for supplying / shutting off the desulfurization gas. . In the present embodiment, city gas containing a compound containing carbon and hydrogen as a main component is used as a raw material. A typical city gas is mostly methane and partly contains butane.

The operation of the fuel cell power generation system in this embodiment will be described. When generating power, first open / close valve 14
Is opened, and the desulfurized gas obtained by removing the sulfur component of the city gas by the desulfurizer 13 is supplied from the desulfurized gas supply pipe 12 to the fuel gas supply pipe 10
Is injected into the fuel electrode 11a of the fuel cell 11 through. As a result, the gas remaining in the fuel electrode of the fuel cell and its vicinity is discharged to the outside of the fuel cell 11, and the atmosphere of the fuel gas flow path inside the fuel cell including the fuel electrode 11a is purged with desulfurization gas. In this specification, purging means discharging, and in other words, replacing existing substances such as gas existing in a certain space with substances such as purging gas. .

When the purging of the internal atmosphere of the fuel gas passage including the fuel electrode 11a with the desulfurization gas is completed, the on-off valve 14 is closed to stop the supply of the desulfurization gas and supply the fuel gas and the oxidant gas to the fuel cell 11. Generate electricity. When stopping the power generation, first, the supply of the fuel gas and the oxidant gas to the fuel cell 11 is stopped. Then, the on-off valve 14 is opened and the unreacted fuel gas is injected into the fuel cell 1 by injecting desulfurization gas into the fuel electrode 11a of the fuel cell 11 as before power generation.
1, and the internal atmosphere of the fuel gas passage of the fuel cell including the fuel electrode 11a is purged with desulfurization gas.

The fuel gas supplied to the fuel electrode 11a of the fuel cell 11 is a hydrogen-rich gas and may explode if it comes into direct contact with air. When the power generation of the fuel cell 11 is stopped for a while, external air flows into the fuel electrode 11a of the fuel cell 11 from a pipe or the like. However, with the configuration of the fuel cell power generation system shown in this embodiment, the atmosphere of the fuel gas flow path including the fuel electrode 11a of the fuel cell 11 is first purged with desulfurization gas before the power generation is started, and then the fuel gas is removed. After supplying power to the fuel electrode 11a of the fuel cell 11 and stopping the supply of fuel gas to the fuel electrode 11a of the fuel cell 11 at the end of power generation, the desulfurization gas is used to control the fuel gas flow path including the fuel electrode 11a of the fuel cell 11. Purge atmosphere.

Therefore, there is no danger that the fuel gas remaining inside the fuel cell 11 will come into contact with the air, and there is no risk that the fuel gas will explode inside the fuel cell 11. That is, according to the configuration of the fuel cell power generation system shown in the present embodiment, it is possible to safely start and stop the power generation of the fuel cell without supplying nitrogen. Generally, in a mixed gas of hydrogen gas and air, the hydrogen gas content is 4 to 75% by volume.
It is known that the range of is a flammable range. In some cases, even if it is in the flammable range, it may not burn or explode, but it should be avoided that the flammable range state occurs. Therefore, it is necessary to take care so that the hydrogen gas does not fall into the flammable range during the purging process described above or during the purging process of the following embodiments.

Here, the purging process for purging the atmosphere of the fuel gas passage including the fuel electrode of the fuel cell with desulfurization gas both before and after the start of power generation has been described. However, for the purging only before the start of power generation, the same purging effect before the start of power generation shown in the above operation description, and for the purging only after the end of power generation, the same purging effect after the end of power generation shown in the above operation description, Obtained independently.

<< Embodiment 2 >> FIG. 2 is a configuration diagram showing a fuel cell power generation system according to Embodiment 2 of the present invention.
The fuel cell power generation system according to the present embodiment first includes a fuel cell 11 that generates power using a fuel gas and an oxidant gas,
A desulfurizer 16 is provided which has a compound containing carbon and hydrogen such as hydrocarbon represented by city gas as a main component and which removes a sulfur component from a gas as a raw material containing a sulfur component.

In this embodiment, city gas is used as the source gas. The fuel cell power generation system according to the present embodiment further includes a reaction section 15a for steam-reforming desulfurized city gas to generate hydrogen-rich fuel gas, and a burner 15b as a heating means for carrying out the reforming reaction. The fuel gas generator 15, the fuel gas supply pipe 19 for supplying the fuel gas to the fuel cell 11, and the burner 15b for the residual fuel gas.
The residual fuel gas pipe 20 for supplying to the fuel cell 11
1, a blower 17 for supplying air as an oxidant gas, and a desulfurization gas supply pipe 12 for supplying a desulfurization gas obtained by removing sulfur components from city gas to a fuel gas supply pipe 19.
Further, the desulfurization gas supply pipe 12 is provided with a desulfurizer 13 for removing sulfur components from city gas, and an opening / closing valve 14 for supplying / shutting off the desulfurization gas.

Further, a fuel cell bypass pipe 21 from the fuel gas supply pipe 19 to the residual fuel gas pipe 20 is provided, and the fuel gas from the fuel gas generator 15 is supplied to the fuel cell 11 by the passage switching valve 18. Alternatively, exhaust is performed from the fuel cell bypass pipe 21. Further, an opening / closing valve 22 is provided upstream of the confluence portion of the residual fuel gas pipe 20 with the fuel cell bypass pipe 21. Further, if necessary, carbon monoxide concentration detecting means 32 for detecting the carbon monoxide concentration in the fuel gas generated by the fuel gas generating section 15, and the carbon monoxide concentration detecting means 32.
And a control unit 33 for controlling the opening / closing of the on-off valve 14 based on the detection value detected by.

The fuel cell power generation system according to this embodiment shown in FIG. 2 and the flow chart of the first example of the start-up method including the specific purging step using desulfurized gas according to this embodiment shown in FIG. An example of the starting operation of the fuel cell power generation system in the embodiment will be described. Before the power generation of the fuel cell power generation system is started, the flow passage switching valve 18 first switches the flow passage so that the fuel gas flows through the fuel cell bypass pipe 21.
Next, the opening / closing valves 14 and 22 are opened, and the desulfurization gas from which the sulfur component has been removed from the city gas by the desulfurizer 13 is injected from the desulfurization gas supply pipe 12 into the fuel gas supply pipe 19, whereby the fuel electrode of the fuel cell 11 is discharged. 11a and flow path switching valve 1
The internal atmosphere of the fuel gas supply pipe 19 downstream of 8 and the internal atmosphere of the residual fuel gas pipe 20 upstream of the on-off valve 22 are purged with desulfurization gas.

When the purging with the desulfurization gas is completed, the on-off valves 14 and 22 are closed. After that, the desulfurization gas from which the sulfur component has been removed by the desulfurizer 16 is supplied to the fuel gas generation unit 15, and after the fuel gas component is in a state where the fuel cell 11 can generate electricity, the on-off valve 22 is opened and the flow is changed. The fuel gas flow path is connected to the fuel cell 11 by the path switching valve 18,
Fuel gas is supplied to the first fuel electrode 11a. At the same time, power is generated by supplying air to the air electrode of the fuel cell 11 by the blower 17.

The fuel gas supplied to the fuel electrode 11a of the fuel cell 11 is a hydrogen-rich gas and may explode if it comes into direct contact with air. However, if the purging step in the present embodiment is performed, the atmosphere of the fuel gas flow passage between the flow passage switching valve 18 and the opening / closing valve 22 is purged with desulfurization gas before the start of power generation, and then the fuel gas is fueled during power generation. It is supplied to the fuel electrode 11a of the battery 11 to generate electricity.

Therefore, even if air is contained in the gas remaining in the fuel electrode 11a of the fuel cell 11 before the start of operation, that is, before the purging step, there is no danger of contact between the air and the fuel gas, and the fuel gas There is no risk of explosion inside the fuel cell 11. That is, according to the configuration of the fuel cell power generation system according to the present embodiment and the specific purging process of the atmosphere of the fuel gas flow path with the desulfurization gas according to the present embodiment, in the operation of the fuel cell power generation system, safe starting is performed by supplying nitrogen. Can be realized without.

Next, referring to the flow chart of the operation stopping method including the fuel cell power generation system having the structure shown in FIG. 2 and the purging step with desulfurization gas of this embodiment shown in FIG. 4, the fuel cell power generation in this embodiment 2 will be described. An example of the operation stop operation of the system will be described. At the end of power generation of the fuel cell power generation system,
First, the flow passage switching valve 18 connects the fuel gas flow passage to the fuel cell bypass pipe 21 to stop the supply of the raw material gas, city gas. Then, the on-off valve 14 is opened, the desulfurization gas is injected into the fuel gas supply pipe 19, and the atmosphere of the flow passage between the flow passage switching valve 18 and the on-off valve 22 is purged with the desulfurization gas.

When this purging process is completed, the on-off valve 14
The on-off valve 22 is closed and the operation is completed. The fuel gas supplied to the fuel electrode 11a of the fuel cell 11 is a hydrogen-rich gas and may explode if it comes into direct contact with air. However, when the purging step in this embodiment is performed, after the power generation is finished, the supply of the fuel gas to the fuel electrode 11a of the fuel cell 11 is stopped, and then the flow path switching valve 18 to the on-off valve 22 is desulfurized. Since the flow path atmosphere is purged, the fuel gas hardly remains at the fuel electrode 11a of the fuel cell 11.

Therefore, even if air flows into the fuel electrode 11a of the fuel cell 11, no fuel gas remains, so there is no risk of explosion inside the fuel cell 11. That is, according to the configuration of the fuel cell according to the present embodiment and the specific purging process according to the present embodiment, it is possible to realize a safe operation stop of the fuel cell power generation system without supplying nitrogen. In the present purging process, the on-off valve 22 is closed when the purging is completed, but the operation may be ended particularly when the on-off valve 22 is opened.

Next, referring to the flow chart of the second example of the starting method including the fuel cell power generation system of the present embodiment shown in FIG. 2 and the specific purging process using desulfurized gas of the present embodiment shown in FIG. Another example of the starting operation of the fuel cell power generation system in the present embodiment will be described. The on-off valve 22 is not always necessary in this fuel cell power generation system. However, in the description of the operation, the configuration in which the on-off valve 22 is always opened and installed will be described.

Before the power generation of the fuel cell power generation system is started, the flow passage switching valve 18 first switches the flow passage so that the fuel gas flows through the fuel cell bypass pipe 21. Next, the on-off valve 14 is opened, and the desulfurization gas from which the sulfur component has been removed from the city gas by the desulfurizer 13 is injected into the fuel gas supply pipe 19 from the desulfurization gas supply pipe 12 so that the fuel electrode 11a of the fuel cell 11 is connected. Fuel gas supply pipe 1 downstream of the flow path switching valve 18
The internal atmosphere of 9 and the internal atmosphere of the residual fuel gas pipe 20 upstream of the on-off valve 22 are purged with desulfurization gas.

When the purging process with the desulfurization gas is completed, the desulfurization gas from which the sulfur component has been removed by the desulfurization unit 16 is supplied to the fuel gas generation section 15, and the fuel gas component is in a state where the fuel cell 11 can generate electricity. After that, the supply of the desulfurization gas is stopped by closing the opening / closing valve 14. Next, the flow path switching valve 1
Fuel gas is supplied to the fuel cell 11 by 8 and air is simultaneously supplied to the fuel cell 11 by the blower 17 to generate power.

When the starting method described based on the flow chart of the second example is performed, the following effects can be obtained in addition to the effect described in the electromotive method shown in the flow chart of the first example of FIG. . That is, when the fuel cell power generation system is started, the fuel gas generated in the fuel gas generation unit 15 contains a high concentration of carbon monoxide. Therefore, if this gas flows into the fuel electrode, the fuel electrode will be poisoned. become. However, as described above, since the desulfurization gas is injected into the fuel gas supply pipe 19 at the time of start-up, the fuel gas containing high concentration of carbon monoxide is released from the fuel cell bypass pipe 21 through the open / close valve 22 and the fuel electrode. It is possible to prevent the diffuse inflow to the.

Therefore, according to the start-up method of the specific example of the present embodiment, safe start-up can be realized in the operation of the fuel cell power generation system without supplying nitrogen, and
It is possible to prevent carbon monoxide poisoning of the fuel electrode 11a of the fuel cell 11 at startup. In the fuel cell power generation system described above, a carbon monoxide concentration detecting means 32 for detecting the carbon monoxide concentration in the fuel gas generated by the fuel gas generation unit 15, and the carbon monoxide concentration detection, as necessary. A control unit 33 for controlling opening / closing of the opening / closing valve 14 based on the detection value detected by the means 32 is further provided.

The open / close valve 14 is opened to inject desulfurizing gas into the fuel electrode 11a until the detection value detected by the carbon monoxide concentration detecting means 32 falls below a predetermined value, and after the detection amount falls below the predetermined value, the opening / closing is performed. By setting the control unit 33 to close the valve 14 and stop the injection of the desulfurization gas, it is possible to prevent carbon monoxide from diffusing into the fuel cell 11.
The amount of desulfurization gas used can be appropriately controlled. In the above description of the operation, the on-off valve 22 is always open, but the same effect can be obtained with a configuration in which the on-off valve 22 is removed, and cost reduction can be realized by reducing the number of parts.

<< Embodiment 3 >> FIG. 6 is a block diagram showing a fuel cell power generation system according to Embodiment 3 of the present invention.
The same components as those in FIG. 2 showing the second embodiment are designated by the same reference numerals, and the description thereof will be omitted. Reference numeral 23 designates a desulfurization gas obtained by removing a sulfur component from a gas as a raw material containing a sulfur component as a main component of a compound of carbon and hydrogen such as hydrocarbon represented by city gas by a desulfurizer 16 in a fuel gas generating section 15. It is a fuel gas generation part bypass pipe for bypassing and supplying directly to the fuel cell 11. In this embodiment,
City gas is used as a raw material gas.

The fuel gas generator bypass pipe 23 is provided with an on-off valve 24. Further, the pipe for supplying the desulfurization gas as the raw material gas to the fuel gas generation unit 15 has a raw material gas supply valve 25 for supplying / stopping the raw material gas. Further, if necessary, the carbon monoxide concentration detecting means 32 for detecting the carbon monoxide concentration in the fuel gas generated by the fuel gas generating section 15 and the detection value detected by the carbon monoxide concentration detecting means 32 are used. A control unit 34 for controlling the opening / closing of the opening / closing valve 24 is provided.

Referring to the flow chart of the fuel cell power generation system shown in FIG. 6 and the first example of the specific electromotive method shown in FIG. 7,
An example of the electromotive operation of the fuel cell power generation system in Embodiment 3 will be described. Before the power generation of the fuel cell power generation system is started, the flow passage switching valve 18 first switches the flow passage so that the fuel gas flows through the fuel cell bypass pipe 21. Then,
The open / close valve 24 and the open / close valve 22 are opened, the raw material gas supply valve 25 is closed, and the desulfurization gas from which the sulfur component has been removed from the gas as the raw material such as city gas by the desulfurizer 16 is fed from the fuel gas generation bypass pipe 23 to the fuel. By injecting into the gas supply pipe 19, the fuel electrode 11a of the fuel cell 11 and the flow path switching valve 1
The internal atmosphere of the fuel gas supply pipe 19 downstream of 8 and the internal atmosphere of the residual fuel gas pipe 20 upstream of the on-off valve 22 are purged with desulfurization gas.

When the purging process with the desulfurization gas is completed, the on-off valve 24 and the on-off valve 22 are closed, and then the raw material gas supply valve 25 is opened to supply the raw material gas to the fuel gas generating section 15. Then, after the components of the fuel gas are in a state in which the fuel cell 11 can generate electricity, the on-off valve 22 is opened and the flow path switching valve 1
Fuel gas is supplied to the fuel cell 11 by 8 and air is simultaneously supplied to the fuel cell 11 by the blower 17 to generate power.

When the purging step with the desulfurization gas is performed, the atmosphere of the fuel gas passage between the passage switching valve 18 and the opening / closing valve 22 is purged with the desulfurization gas before the power generation is started, and then the fuel gas is generated during the power generation. Is supplied to the fuel electrode 11a of the fuel cell 11 to generate electric power, so that the gas remaining in the fuel gas passage including the fuel electrode 11a of the fuel cell 11 before the start of operation, that is, before the purging step contains air. However, there is no danger of the air and fuel gas coming into contact with each other, and there is no risk of the fuel gas exploding inside the fuel cell 11.

Furthermore, by using the desulfurization gas for purging the atmosphere requiring purging from the same source as the source gas, a simpler and more effective system can be realized. That is, according to the configuration of the fuel cell power generation system shown in the present embodiment and the specific purging process of the present embodiment, in the operation of the fuel cell power generation system, a more effective system and a safe start are realized without supplying nitrogen. be able to.

Next, referring to the flow chart of the fuel cell power generation system of the present embodiment shown in FIG. 6 and the first example of the specific shutdown method of the present embodiment shown in FIG. 8, the fuel in the present embodiment will be described. An example of the operation stop operation of the battery power generation system will be described. At the end of power generation of the fuel cell power generation system, first, the flow path switching valve 18 connects the fuel gas flow path to the fuel cell bypass pipe 21, and the raw material gas supply valve 25 is closed to stop the supply of the raw material gas. Next, the on-off valve 24 is opened, and the desulfurization gas desulfurized by the desulfurizer 16 is injected from the fuel gas generation part bypass pipe 23 into the fuel gas supply pipe 19.
The atmosphere of the fuel gas passage between the passage switching valve 18 and the opening / closing valve 22 is purged with desulfurization gas.

When this purging process is completed, the on-off valve 24
The on-off valve 22 is closed and the operation is completed. The fuel gas supplied to the fuel electrode 11a of the fuel cell 11 is a hydrogen-rich gas and may explode if it comes into direct contact with air. However, when the above-described purging process is performed, after the power generation is completed, the supply of the fuel gas to the fuel electrode 11a of the fuel cell 11 is stopped, and then the desulfurization gas is applied to the portion between the flow path switching valve 18 and the on-off valve 22. Since the atmosphere of the fuel gas flow path is purged, almost no fuel gas remains on the fuel electrode 11a of the fuel cell 11. Therefore, even if air flows into the fuel electrode 11a of the fuel cell 11, no fuel gas remains, so there is no risk of explosion inside the fuel cell 11.

That is, according to the configuration of the fuel cell shown in the present embodiment and the specific purging process, it is possible to safely stop the operation of the fuel cell power generation system without supplying nitrogen. In this purging process, the on-off valve 22 is closed when the purging is completed.
The operation may be ended in the state where 2 is opened.

Next, referring to the flow chart of the fuel cell power generation system of the present embodiment shown in FIG. 6 and the second example of the specific shutdown method of the present embodiment shown in FIG. 9, the fuel in the present embodiment will be described. Another example of the operation stop operation of the battery power generation system will be described. When the power generation of the fuel cell power generation system is finished, first, the fuel gas flow passage is connected to the fuel cell bypass pipe 21 by the flow passage switching valve 18, and the raw material gas supply valve 25 is kept open to continue the supply of the raw material gas. Generate. Then, the on-off valve 24 is opened, and the desulfurized gas desulfurized by the desulfurizer 16 is fed from the fuel gas generator bypass pipe 23 to the fuel gas supply pipe 19
And the atmosphere of the fuel gas passage between the passage switching valve 18 and the opening / closing valve 22 is purged with desulfurization gas.

When this purging process is completed, the raw material gas supply valve 25 is closed, the supply of the raw material gas is stopped, and the open / close valve 24 is opened.
The on-off valve 22 is closed and the operation is completed. The fuel gas supplied to the fuel electrode 11a of the fuel cell 11 is a hydrogen-rich gas and may explode if it comes into direct contact with air. However, when the purging step in this embodiment is performed, after the power generation is finished, the supply of the fuel gas to the fuel electrode 11a of the fuel cell 11 is stopped, and then the flow path switching valve 18 to the on-off valve 22 is desulfurized. Since the flow path atmosphere is purged, the fuel gas hardly remains at the fuel electrode 11a of the fuel cell 11.

Therefore, even if air flows into the fuel electrode 11a of the fuel cell 11, no fuel gas remains, so there is no risk of explosion inside the fuel cell 11. Further, since both the desulfurization gas and the raw material gas return to the burner 15b, the burner 15b can realize stable combustion without causing misfire. That is, according to the configuration of the fuel cell shown in the present embodiment and the specific purging process of the present embodiment, in the operation of the fuel cell power generation system, a safe shutdown can be realized without supplying nitrogen, and a stable burner at the end can be achieved. Combustion can be realized. In this purging process, the on-off valve 22 is closed when the purging is completed.
The operation may be ended in the state where 2 is opened.

Next, referring to the flow chart of the fuel cell power generation system of the third embodiment shown in FIG. 6 and the second example of the concrete electromotive method of the present embodiment shown in FIG. 10, the present embodiment will be described. Another example of the electromotive operation of the fuel cell power generation system will be described.
The on-off valve 22 is not required in this fuel cell power generation system. However, in the description of the operation, the configuration in which the on-off valve 22 is always opened and installed will be described.

Before the power generation of the fuel cell power generation system is started, the flow passage switching valve 18 first switches the flow passage so that the fuel gas flows through the fuel cell bypass pipe 21. Then, the on-off valve 24 is opened, the raw material gas supply valve 25 is closed, and the desulfurization gas from which the sulfur component has been removed from the city gas by the desulfurizer 16 is injected into the fuel gas supply pipe 19 from the fuel gas generation bypass pipe 23. The internal atmosphere of the fuel gas supply pipe 19 downstream of the fuel cell 11 and the flow path switching valve 18 and the opening / closing valve 22.
The internal atmosphere of the residual fuel gas pipe 20 on the upstream side is purged with desulfurization gas.

When the purging process with the desulfurization gas is completed, the raw material gas supply valve 25 is opened thereafter, and the desulfurized gas from which sulfur components have been removed from the gas as the raw material such as city gas by the desulfurizer 16 is supplied to the fuel gas generating section 15 Supply to. In this embodiment, city gas is used as the source gas. After the components of the fuel gas generated by the fuel gas generation unit 15 are in a state where the fuel cell 11 can generate electricity, the supply of desulfurized gas to the fuel gas supply pipe 19 is stopped by closing the opening / closing valve 24. On the other hand, the flow path switching valve 18 is switched to supply the fuel gas from the fuel gas generator 15 to the fuel cell 11, and at the same time, the blower 1
Electric power is generated by supplying air to the fuel cell 11 through 7.

When the activation method of another example based on the flow chart of the second example in the present embodiment is performed, the following effects are obtained in addition to the effect explained in the electromotive method whose flow chart of the first example is shown in FIG. can get. That is, when the fuel cell system is activated, the fuel gas generated in the fuel gas generation unit 15 contains a high concentration of carbon monoxide, but the desulfurization gas, which is a specific operation of the present invention, is supplied to the fuel gas supply pipe. By injecting into the fuel cell 19, it is possible to prevent the fuel gas from diffusingly flowing into the fuel electrode 11a of the fuel cell 11.

Therefore, the specific electromotive method of the present embodiment based on the above-mentioned another example can realize safe start-up without supplying nitrogen in the operation of the fuel cell power generation system, and the fuel cell at the time of start-up. 11 fuel electrode 11a
It is possible to realize the prevention of carbon monoxide poisoning.
In the fuel cell power generation system described above, a carbon monoxide concentration detection means 32 for detecting the carbon monoxide concentration in the fuel gas generated by the fuel gas generation unit 15 is further provided as necessary.
And a control unit 34 for controlling the opening and closing of the on-off valve 24 based on the detection value detected by the carbon monoxide concentration detection means 32.

The open / close valve 24 is opened to inject desulfurization gas into the fuel electrode 11a until the detection value detected by the carbon monoxide concentration detection means 32 falls below a predetermined value, and after the detection amount falls below the predetermined value, the opening / closing is performed. By setting the control unit 34 to close the valve 24 and stop the injection of the desulfurization gas, it is possible to prevent carbon monoxide from diffusing into the fuel cell 11.
The amount of desulfurization gas used can be appropriately controlled. In the above description of the operation, the on-off valve 22 is always open, but the same effect can be obtained with a configuration in which the on-off valve 22 is removed, and cost reduction can be realized by reducing the number of parts.

<< Embodiment 4 >> FIG. 11 is a block diagram showing a fuel cell power generation system according to Embodiment 4 of the present invention. The same components as those in FIG. 2 showing the second embodiment are designated by the same reference numerals, and the description thereof will be omitted. In the present embodiment, a blower 26 for supplying air to the desulfurization gas supply pipe 12 downstream of the on-off valve 14 and an on-off valve 27 for shutting off the air supply passage are further provided.

The fuel cell power generation system shown in FIG. 11 and FIG.
The operation stop operation of the fuel cell power generation system in the present embodiment will be described with reference to the flow chart of the specific operation stop method shown in FIG. However, since the operation in the present embodiment is the operation performed after the operation of the system based on the operation stop method shown in the flow chart in FIG. 4 in the second embodiment, the operation of the fuel gas passage including the fuel electrode 11a of the fuel cell 11 is performed. A description will be given after the atmosphere is purged with desulfurization gas.

Upon completion of the desulfurization gas purging step,
The on-off valve 14 is closed, the on-off valve 27 is opened, and air is injected into the fuel gas supply pipe 19 from the desulfurization gas supply pipe 12 by the blower 26, so that the fuel gas flow between the flow path switching valve 18 and the on-off valve 22 is increased. Purge the atmosphere of the tract with air. When the air purging is completed, the blower 26 is stopped, the opening / closing valve 27 is closed, and the system operation is finished.

When the purging step in this embodiment is performed, the atmosphere of the fuel gas passage between the passage switching valve 18 and the opening / closing valve 22 is first purged with desulfurization gas, and then the desulfurization gas atmosphere in the same section is purged with air. Therefore, the fuel cell 11 can be maintained in a very safe state at the end of the operation. Further, since the fuel gas and the air do not come into contact with each other, there is no possibility of explosion inside the fuel cell 11. That is, the configuration of the fuel cell power generation system shown in the present embodiment and the specific purging step of the present embodiment realize a safe shutdown in the operation of the fuel cell power generation system without supplying nitrogen,
Moreover, the safe holding of the fuel cell 11 when the operation is stopped can be realized.

<< Fifth Embodiment >> FIG. 13 is a configuration diagram showing a fuel cell power generation system according to a fifth embodiment of the present invention. The same components as those in FIG. 6 showing the third embodiment are designated by the same reference numerals, and the description thereof will be omitted. The present embodiment further includes a steam generator 28 that is a means for purging the internal atmosphere of the fuel gas generator 15 with steam.

The fuel cell power generation system shown in FIG. 13 and FIG.
An example of the operation stop operation of the fuel cell power generation system according to the present embodiment will be described with reference to the flowchart of the first example of the specific operation stop method shown in FIG. However, the operation stop operation described in this specific example is an operation performed after the purge step described in the operation stop method whose flow chart is shown in FIG. 9 in the third embodiment. Therefore, the fuel electrode 1 of the fuel cell 11
A description will be given after the step of purging the atmosphere of the fuel gas passage containing 1a with the desulfurization gas.

When the purging process of the fuel gas flow path with the desulfurization gas is completed, the raw material gas supply valve 25 is closed, and then the open / close valve 24 and the open / close valve 22 are closed. Then, the steam generator 28
More steam is supplied to the fuel gas generation unit 15, and the internal atmosphere thereof is purged with steam. When the steam purging process is completed, the steam generator 28 is stopped and the operation is terminated. By performing the purging step in this embodiment, the following effects can be obtained in addition to the effects described in the third embodiment whose flow chart is shown in FIG.

First, since the internal atmosphere of the fuel gas generator 15 is purged with water vapor, almost no combustible gas remains in the fuel gas passage. Further, by injecting water vapor into the fuel gas generation unit 15, cooling of the fuel gas generation unit 15 is promoted, and the time until the end of operation can be shortened. That is, the configuration of the fuel cell power generation system shown in the present embodiment and the specific purging process of the present embodiment realizes a safe shutdown without supplying nitrogen in the operation of the fuel cell power generation system and stabilizes at the end. It is possible to realize burner combustion and to remove combustible gas in the fuel gas passage. Furthermore, the time until the end of operation can be shortened. In this purging process, the opening / closing valve 22 is closed at the end of the operation, but the operation may be ended particularly with the opening / closing valve 22 opened.

Next, referring to the flow chart of the fuel cell power generation system shown in FIG. 13 and the second example of the specific operation stop method shown in FIG. 15, the operation of the fuel cell power generation system in this embodiment will be stopped. Another example will be described. At the end of power generation of the fuel cell power generation system, first, the fuel gas flow passage is connected to the fuel cell bypass pipe 21 by the flow passage switching valve 18, the raw material gas supply valve 25 is closed, and the supply of raw material gas is stopped. Then, the steam is generated from the steam generator 28 and the fuel gas generating unit 15
And purge the internal atmosphere with steam.

On the other hand, for the fuel cell 11, the open / close valve 24 is opened at the end of power generation, and the desulfurized gas desulfurized by the desulfurizer 16 is injected from the fuel gas generator bypass pipe 23 into the fuel gas supply pipe 19 to switch the flow path. The flow path atmosphere from the valve 18 to the on-off valve 22 is purged with desulfurization gas. When the purging of the flow path from the fuel gas generating unit 15 to the fuel cell bypass pipe 21 with the steam is completed, the steam generator 28 is stopped and the purging with the steam is completed. Further, when the purging of the flow passage atmosphere between the flow passage switching valve 18 and the opening / closing valve 22 with desulfurization gas is completed, the raw material gas supply valve 25 is closed to stop the supply of the raw material gas, city gas, and the opening / closing valve 24. Then, the on-off valve 22 is closed to complete the purging with the desulfurization gas.

By performing the purging step in this embodiment, the following effects can be obtained in addition to the effects described in the third embodiment. First, since the internal atmosphere of the fuel gas generator 15 is purged with water vapor, almost no combustible gas remains in the fuel gas passage. Further, by injecting water vapor into the fuel gas generation unit 15, cooling of the fuel gas generation unit 15 is promoted, and the time until the end of operation can be shortened. Moreover, since the internal atmospheres of the two reaction parts, the fuel gas generation part 15 and the fuel cell 11, can be simultaneously and independently purged, the time until the end of the operation can be further shortened.

That is, the configuration of the fuel cell power generation system shown in this embodiment and the specific purging process of this embodiment are as follows.
In the operation of the fuel cell power generation system, it is possible to realize a safe shutdown without supplying nitrogen and to remove the combustible gas in the fuel gas passage. Further, since the internal atmospheres of the two reaction parts are simultaneously and independently purged, the time until the end of the operation can be shortened. In the present purging process, the on-off valve 22 is closed when the purging process using desulfurization gas is completed, but the operation may be terminated particularly when the on-off valve 22 is opened.

<< Sixth Embodiment >> FIG. 16 is a configuration diagram showing a fuel cell power generation system according to a sixth embodiment of the present invention. The same components as those in FIG. 13 showing the fifth embodiment are designated by the same reference numerals, and the description thereof will be omitted. The present embodiment further includes a desulfurization gas supply valve 29 that supplies and stops the desulfurization gas, a blower 30 that supplies air upstream of the fuel gas generation unit 15, and an opening / closing valve 31 that shuts off the air supply passage.

The operation of the fuel cell power generation system in this embodiment will be described with reference to the fuel cell power generation system shown in FIG. However, the feature of the operation in this embodiment is that
In the fifth embodiment, the operation is performed after the purging step using desulfurization gas and steam described with reference to the flowchart of FIG. 14 or 15. Therefore, a description will be given later of the purging process of the internal atmosphere of the fuel gas generation unit 15 with water vapor and the purging process of the fuel gas passage atmosphere including the fuel electrode 11a of the fuel cell 11 with the desulfurization gas.

When the purging process with steam is completed, the desulfurization gas supply valve 29 is closed. After that, the blower 30 is operated and the opening / closing valve 31 is opened, so that the fuel gas generator 15
By supplying air to the fuel gas generator 15, the water vapor remaining inside the fuel gas generator 15 is removed to the fuel gas supply pipe 19. Air is also supplied to the fuel electrode 11a of the fuel cell 11 using the blower 30. As a result, the desulfurization gas supply valve 29
It is possible to safely purge the atmosphere of the fuel gas flow path on the further downstream side with air, and further, it is possible to realize safe holding of the fuel cell 11 when the operation is stopped. Further, since the air is purged, the fuel gas passage downstream of the raw material gas supply valve 29 can be opened to the atmosphere, and even if the fuel gas generation unit 15 causes a pressure decrease due to a temperature decrease,
It is relieved by inhaling air from the atmosphere.

Next, as a more effective air purging step, the present embodiment will be described with reference to the flow chart of the first example of the fuel cell power generation system shown in FIG. 16 and the concrete operation stopping method shown in FIG. An example of operation stop operation of the fuel cell power generation system in FIG. When the purging of the internal atmosphere of the fuel gas generation unit 15 with water vapor and the purging of the fuel gas flow path atmosphere including the fuel electrode 11a of the fuel cell 11 with desulfurization gas are completed, the desulfurization gas supply valve 29 is closed. Then, the opening / closing valves 31 and 22 are opened, and the flow passage is connected to the fuel cell 11 by the flow passage switching valve 18. After that, the blower 30 is operated, and the air is purged from the fuel gas generation unit 15 to the burner 15b through the fuel electrode 11a of the fuel cell 11 to purge the atmosphere of the entire fuel gas flow path.

After the completion of this purging process, the blower 30 is stopped and the opening / closing valve 31 is closed to end the operation. In this purging process, the air for purging the atmosphere requiring purging is supplied from the upstream side of the fuel gas generation unit 15,
Do not branch the flow path. Therefore, the atmosphere can be purged by air from the upstream side of the fuel gas flow path to the downstream side along the flow path. That is, the configuration of the fuel cell power generation system according to the present embodiment and the purging process of this specific example have the same effects as those of the fuel cell power generation system described at the beginning of the sixth embodiment, and the flow channels are sequentially passed from the upstream of the fuel gas flow channel. There is also an effect that it is possible to realize purging of the atmosphere by air along the downstream.

Next, as another effective method of the air purging step, referring to the flow chart of the second example of the fuel cell power generation system shown in FIG. 16 and the concrete operation stop method shown in FIG. Another example of the operation stop operation of the fuel cell power generation system in the embodiment will be described. When the purging of the internal atmosphere of the fuel gas generation unit 15 with water vapor and the purging of the fuel gas flow path atmosphere including the fuel electrode 11a of the fuel cell 11 with the desulfurization gas are completed, the desulfurization gas supply valve 29 is closed.

Then, the on-off valves 31, 24, 22 and the raw material gas supply valve 25 are opened. Furthermore, the flow passage switching valve 18 connects the flow passage to the fuel cell bypass pipe 21. After that, the blower 30 is operated to move air from the fuel gas generation unit 15 to the burner 15b through the fuel cell bypass pipe 21, and further from the fuel gas generation unit bypass pipe 23 to the fuel electrode 11 of the fuel cell 11.
The atmosphere of the entire fuel gas flow path is purged with air by flowing it to the burner 15b via a.

After the completion of this purging process, the blower 30 is stopped and the opening / closing valve 31 is closed to end the operation. In this purging step, the internal atmosphere of the fuel gas generator 15 and the atmosphere of the fuel gas flow path including the fuel electrode 11a of the fuel cell 11 are simultaneously purged, so that the purging can be performed in a short time. That is, the configuration of the fuel cell power generation system shown in the present embodiment and the purging process of this specific example are the same as those in the sixth embodiment.
In addition to the effect similar to that of the fuel cell power generation system described in the first paragraph, there is also an effect that the purging process with air can be completed in a short time.

By the way, the fuel gas generator 15 of the fuel cell power generation system in Embodiments 4 and 6 above.
In the reaction section 15a, air may or may flow into the reaction section 15a during the process of purging with air. Therefore, the reaction section 15a of the fuel gas generation section 15
As shown in FIG. 19, a shift portion 15d provided with a shift catalyst body containing at least a noble metal and a metal oxide as constituent materials.
It is more effective to provide the reforming unit 15c which is a hydrogen gas supply unit for supplying hydrogen gas containing at least carbon monoxide and water vapor as sub-components to the shift conversion unit.

That is, in FIG. 19, the raw material gas or the desulfurization gas is supplied to the reformer 15c, and the reformer 15c is supplied.
The reforming reaction of the raw material gas or the desulfurization gas is caused at a high temperature where steam exists in c. Carbon monoxide as a by-product in the reforming reaction is reacted with steam in the next shift conversion section 15d to generate hydrogen and carbon dioxide.
The burner 15b has a role of raising the temperature of the reformer 15c.

According to this structure, since the shift catalyst body has resistance to oxygen poisoning, even if air is allowed to flow into the reaction section 15a for the purging step, it is possible to prevent performance deterioration due to air. To be In the first to sixth embodiments, the example in which the city gas is used as the purging gas or the raw material gas has been shown. City gas does not need a cylinder like nitrogen because it is built as a social infrastructure. Therefore, from the viewpoint that a simpler configuration can be realized, the desulfurization gas obtained by removing the sulfur component from the city gas was used as a more effective purging gas.

However, the same effect can be obtained by using, as the purging gas, a gas containing as a main component a compound containing at least carbon and hydrogen, such as a hydrocarbon containing no sulfur component. At this time,
No desulfurizer is required, and the same raw material for generating hydrogen can be used as the purging gas. Other than these city gas or methane gas, natural gas,
Propane gas, dimethyl ether gas and the like can also be used as the raw material gas or the purging gas.

[0111]

As described above, according to the fuel cell power generation system or the fuel cell power generation method of the present invention, the replacement gas, at least one of before the start of power generation and after the end of power generation,
Particularly, in a fuel cell provided with a fuel gas generating means, a raw material containing a compound containing carbon and hydrogen as a main component is injected as a replacement gas into a fuel gas flow path including a fuel electrode, similarly to the gas supplied to the fuel gas generating means. By doing so, the gas remaining in the fuel gas passage can be removed and the atmosphere in the fuel gas passage can be replaced with the replacement gas.

Further, in the fuel cell power generation system or the fuel cell power generation method provided with the air supply means, after the atmosphere of the fuel gas passage including the fuel electrode of the fuel cell is replaced with the replacement gas, the air is supplied by the air supply means. By injecting into the fuel gas channel, the atmosphere of the gas channel can be replaced with air. Further, the fuel gas generation system generates the fuel gas until the injection of the replacement gas into the fuel gas flow path including the fuel electrode of the fuel cell is completed, so that stable combustion in the burner can be realized until the replacement is completed. Alternatively, a fuel cell power generation method can be provided.

Further, by providing the steam supply means, the fuel gas generation means stops the fuel gas generation after the replacement gas injection into the fuel gas passage including the fuel electrode of the fuel cell is completed, and By injecting water vapor into the fuel gas generation means, the fuel gas remaining in the fuel gas generation means can be removed and the atmosphere inside the fuel gas generation means can be replaced with water vapor.

After the power generation of the fuel cell power generation system or power generation method is completed, the fuel gas generation of the fuel gas generation means is stopped, the steam is injected into the fuel gas generation means by the steam supply means, and the replacement gas is used as the fuel. By injecting into the fuel gas flow path including the fuel electrode of the cell, the fuel gas remaining in the fuel gas generation means is removed, the atmosphere inside the fuel gas generation means is replaced with water vapor, and The remaining fuel gas can be removed, and the atmosphere of the fuel gas passage can be replaced with the replacement gas. Moreover, the replacement time can be shortened because the replacement is performed independently at the same time.

Further, after the replacement gas is injected into the fuel gas passage including the fuel electrode of the fuel cell and the steam is injected into the inside of the fuel gas generating means to replace the respective atmospheres,
By injecting air into both the fuel gas flow path and the fuel gas generation means of the fuel cell by the air supply means, the atmosphere of the raw material inside the system and the entire flow path of the fuel can be replaced with air. Further, the fuel gas generating means is provided with the shift conversion portion provided with the shift catalyst body composed of the noble metal and the metal oxide, so that the shift catalyst body can be formed even if air enters the inside of the fuel gas generating means due to the air displacement. The performance deterioration of can be prevented.

By continuously injecting the replacement gas into the fuel gas flow path including the fuel electrode of the fuel cell for an arbitrary time period from the start of operation of the fuel cell power generation system or the power generation method to the start of power generation, It is possible to remove the gas remaining in the gas flow passage and replace it with a replacement gas, and at the same time, prevent the fuel gas from diffusing into the fuel gas flow passage. Further, the fuel containing the fuel electrode of the fuel cell is passed through the bypass means for bypassing the fuel gas generation means for an arbitrary time period from the start of operation of the fuel cell power generation system or the power generation method to the start of power generation. By continuing to inject into the gas flow path, the gas remaining in the fuel gas flow path is removed, the atmosphere in the fuel gas flow path is replaced with the raw material as the replacement gas, and the fuel gas diffuses It can be prevented from flowing into the flow path.

Further, by continuously injecting the replacement gas or the raw material into the fuel gas passage including the fuel electrode until the detection value detected by the carbon monoxide concentration detecting means falls below a predetermined value, the fuel gas diffuses the fuel. It is possible to prevent the gas from flowing into the gas flow passage, and to appropriately manage the amount of the replacement gas or the raw material injected into the fuel gas flow passage. The replacement gas is a fuel gas that does not contain a sulfur component and contains a compound containing at least carbon and hydrogen such as hydrocarbon as a main component, so that the same replacement gas as the raw material can be used. A power generation system or a power generation method can be provided.

[0118] Further, by using a sulfur component removing means for removing the sulfur component contained in the raw material or the replacement gas, and by using either or both of the raw material and the replacement gas as the city gas which is maintained as a social foundation, It is possible to provide a fuel cell power generation system or power generation method having a simpler configuration without the need for a cylinder.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 1 of the present invention.

FIG. 2 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 2 of the present invention.

FIG. 3 is a flowchart showing an example of an electromotive method for a fuel cell power generation system according to Embodiment 2 of the present invention.

FIG. 4 is a flowchart showing an example of a method for stopping the operation of the fuel cell power generation system according to Embodiment 2 of the present invention.

FIG. 5 is a flowchart showing another example of the electromotive method of the fuel cell power generation system according to the second embodiment of the present invention.

FIG. 6 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 3 of the present invention.

FIG. 7 is a flowchart showing an example of an electromotive method for a fuel cell power generation system according to Embodiment 3 of the present invention.

FIG. 8 is a flowchart showing an example of a method for stopping the operation of the fuel cell power generation system according to Embodiment 3 of the present invention.

FIG. 9 is a flowchart showing another example of the method for stopping the operation of the fuel cell power generation system according to the third embodiment of the present invention.

FIG. 10 is a flowchart showing another example of the electromotive method of the fuel cell power generation system according to Embodiment 3 of the present invention.

FIG. 11 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 4 of the present invention.

FIG. 12 is a flowchart showing an example of an operation stop method for a fuel cell power generation system according to Embodiment 4 of the present invention.

FIG. 13 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 5 of the present invention.

FIG. 14 is a flowchart showing an example of a method for stopping the operation of the fuel cell power generation system according to Embodiment 5 of the present invention.

FIG. 15 is a flowchart showing another example of the method for stopping the operation of the fuel cell power generation system according to the fifth embodiment of the present invention.

FIG. 16 is a diagram schematically showing a configuration of a fuel cell power generation system according to Embodiment 6 of the present invention.

FIG. 17 is a flowchart showing an example of a method for stopping the operation of the fuel cell power generation system according to Embodiment 6 of the present invention.

FIG. 18 is a flowchart showing another example of the operation stopping method for the fuel cell power generation system according to the sixth embodiment of the present invention.

FIG. 19 is a diagram schematically showing a configuration of an example of a fuel gas generation unit that can be used in each embodiment of the present invention.

FIG. 20 is a diagram schematically showing a configuration of a conventional fuel cell power generation system.

[Explanation of symbols]

11 Fuel cell 11a Fuel electrode 15 Fuel gas generator 15a Reaction part 15b burner 13, 16 desulfurizer 17, 26, 30 Blower 12 Desulfurization gas supply pipe 14, 22, 24, 27, 31 Open / close valve 18 Flow path switching valve 19 Fuel gas supply pipe 20 Residual fuel gas pipe 21 Fuel cell bypass pipe 23 Fuel gas generator bypass pipe 25 Raw material gas supply valve 28 Steam generator 29 Desulfurization gas supply valve

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinji Miyauchi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Tomonori Aso             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 5H027 AA02 BA01 BA20 BC20 MM04                       MM09 MM12

Claims (34)

[Claims] 1. A fuel cell having a fuel electrode and an oxidant electrode, fuel gas supply means for supplying a fuel gas to a fuel gas flow path of the fuel cell including the fuel electrode, and the fuel including the oxidant electrode. An oxidant gas supply means for supplying an oxidant gas to the oxidant gas flow path of the battery, and a replacement gas supply means for supplying a replacement gas mainly containing a compound containing carbon and hydrogen to the fuel gas flow path are provided. Then, at least one of before and after power generation of the fuel cell is started, the replacement gas is injected into the fuel gas flow path by the replacement gas supply means to replace the atmosphere of the fuel gas flow path with the replacement gas. A fuel cell power generation system characterized in that 2. An air supply means for supplying air to the fuel gas flow path to replace the atmosphere in the fuel gas flow path with air, the replacement gas supply means for replacing the atmosphere after the power generation is completed. After injecting a gas into the fuel gas passage to replace the atmosphere in the fuel gas passage with the replacement gas, the air is injected into the fuel gas passage by the air supply means to inject the fuel gas passage. The fuel cell power generation system according to claim 1, wherein the atmosphere is replaced with the air. 3. The fuel gas supply means supplies a fuel gas generating means for generating a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and the raw material to the fuel gas generating means. 2. The fuel gas generating means includes the raw material supply source, and the fuel gas generating means continues to generate the fuel gas until the replacement gas supplying means completes the injection of the replacement gas into the fuel gas flow path. The fuel cell power generation system described. 4. A steam supply means for supplying steam to the fuel gas generation means to replace the atmosphere inside the fuel gas generation means with steam, further comprising:
After injecting the replacement gas into the fuel gas flow path by the replacement gas supply means to replace the atmosphere in the fuel gas flow path with the replacement gas, the fuel gas generation by the fuel gas generation means is stopped. 4. The fuel cell power generation system according to claim 3, wherein the steam supply unit injects the steam into the fuel gas generation unit to replace the atmosphere inside the fuel gas generation unit with the steam. 5. The fuel gas supply means supplies a fuel gas generating means for generating a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and supplies the raw material to the fuel gas generating means. A raw material supply source, and further comprising steam supply means for supplying steam to the fuel gas generation means to replace the atmosphere inside the fuel gas generation means with the steam, the fuel gas generation means after completion of the power generation. Stopping the generation of the fuel gas, injecting the steam into the fuel gas generating means by the steam supplying means to replace the atmosphere inside the fuel gas generating means with the steam, and supplying the replacement gas. A means for injecting the replacement gas into the fuel gas passage to replace the atmosphere in the fuel gas passage with the replacement gas. Item 2. The fuel cell power generation system according to Item 1. 6. Air for supplying air to the fuel gas flow passage and the fuel gas generating means to replace the atmosphere in the fuel gas flow passage and the atmosphere inside the fuel gas generating means with the air. Further comprising a supply means for injecting the replacement gas into the fuel gas flow path to replace the atmosphere in the fuel gas flow path with the replacement gas, and injecting the water vapor into the fuel gas generation means. After replacing the atmosphere inside the fuel gas generating means with the water vapor,
The air is injected by the air supply means into both the fuel gas flow path and the inside of the fuel gas generation means, so that the atmosphere in the fuel gas flow path and the atmosphere in the fuel gas generation means are the air. 6. The fuel cell power generation system according to claim 4, wherein the fuel cell power generation system is replaced with. 7. The fuel cell power generation system according to claim 6, wherein the air injection by the air supply means is performed in series from the fuel gas generation means to the fuel gas passage. 8. The fuel cell power generation system according to claim 6, wherein the air injection by the air supply means is performed in parallel with the fuel gas generation means and the fuel gas flow path. 9. The shift section in which the fuel gas generating means is provided with a shift catalyst body containing at least a noble metal and a metal oxide as constituent materials, and a hydrogen gas containing at least carbon monoxide and water vapor as auxiliary components in the shift section. The fuel cell power generation system according to any one of claims 6 to 8, further comprising a hydrogen gas supply unit that supplies hydrogen. 10. The fuel cell power generation system according to claim 1, wherein the replacement gas does not contain a sulfur component. 11. A fuel cell having a fuel electrode and an oxidant electrode, a fuel gas generating means for generating a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and the fuel gas generating means. A raw material supply source for supplying the raw material, a fuel gas supply means for supplying the fuel gas from the fuel gas generating means to a fuel gas flow path of the fuel cell including the fuel electrode, and the fuel gas from the raw material supply source. Bypass means for bypassing the generating means and injecting the raw material into the fuel gas flow path as a raw material gas, at least one of before and after power generation of the fuel cell is started via the bypass means. A fuel cell power generation system configured to inject the raw material gas into the fuel gas passage to replace the atmosphere of the fuel gas passage with the raw material gas. 12. The apparatus further comprises air supply means for supplying air to the fuel gas flow path to replace the atmosphere in the fuel gas flow path with the air, and the raw material gas is supplied by the bypass means after completion of the power generation. Is injected into the fuel gas flow passage to replace the atmosphere in the fuel gas flow passage with the raw material gas, and then the air is injected into the fuel gas flow passage by the air supply means to generate the fuel gas flow passage. 12. The fuel cell power generation system according to claim 11, wherein the atmosphere is replaced by the air. 13. The fuel cell according to claim 11, wherein the fuel gas generation means continues to generate the fuel gas until the injection of the raw material gas into the fuel gas passage by the bypass means is completed. Power generation system. 14. The apparatus further comprises steam supply means for supplying steam to the fuel gas generating means to replace the atmosphere inside the fuel gas generating means with the steam, and the raw material gas is supplied by the bypass means after completion of the power generation. Is injected into the fuel gas flow path to replace the atmosphere in the fuel gas flow path with the source gas, and then the fuel gas generation of the fuel gas generation means is stopped, and the fuel gas is supplied by the water vapor supply means. 14. The fuel cell power generation system according to claim 13, wherein the steam is injected into the interior of the generating means to replace the atmosphere inside the fuel gas generating means with the steam. 15. The apparatus further comprises steam supply means for supplying water vapor to the fuel gas generation means to replace the atmosphere inside the fuel gas generation means with the water vapor, and after the power generation is completed, the fuel gas generation means includes While stopping the fuel gas generation, the steam supply unit injects the steam into the fuel gas generation unit to replace the atmosphere inside the fuel gas generation unit with the steam, and
The fuel cell power generation system according to claim 11, wherein the bypass means injects the raw material gas into the fuel gas passage to replace the atmosphere in the fuel gas passage with the raw material gas. 16. Air that supplies air to the fuel gas flow path and the fuel gas generation means to replace the atmosphere in the fuel gas flow path and the atmosphere inside the fuel gas generation means with the air. Further comprising a supply means for injecting the raw material gas into the fuel gas flow passage to replace the atmosphere in the fuel gas flow passage with the raw material gas, and injecting the water vapor into the fuel gas generating means. After replacing the atmosphere inside the fuel gas generation means with the water vapor, the air is injected into the fuel gas flow path and the inside of the fuel gas generation means by the air supply means, and the fuel gas flow path is formed. 16. The fuel cell power generation system according to claim 14, wherein the atmosphere is replaced with the atmosphere inside the fuel gas generation means. 17. The fuel cell power generation system according to claim 16, wherein the air injection by the air supply means is performed in series from the fuel gas generation means to the fuel gas passage. 18. The fuel cell power generation system according to claim 16, wherein the air injection by the air supply unit is performed in parallel with the fuel gas generation unit and the fuel gas flow path. 19. The shift section in which the fuel gas generating means is provided with a shift catalyst body having at least a noble metal and a metal oxide as constituent materials, and a hydrogen gas containing at least carbon monoxide and water vapor as auxiliary components in the shift section. The fuel cell power generation system according to any one of claims 16 to 18, further comprising a hydrogen gas supply unit that supplies hydrogen. 20. The fuel cell power generation system according to claim 11, wherein the raw material supplied from the raw material supply source is a gas obtained by removing sulfur components from city gas. 21. A fuel cell having a fuel electrode and an oxidant electrode, a fuel gas generating means for generating a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and the fuel gas generating means. A raw material supply source for supplying the raw material, a fuel gas supply means for supplying the fuel gas from the fuel gas generating means to a fuel gas flow path of the fuel cell including the fuel electrode, and carbon for the fuel gas flow path. A fuel cell power generation system comprising: a replacement gas supply unit configured to supply a replacement gas containing a compound containing hydrogen as a main component to replace the atmosphere of the fuel gas channel with the replacement gas,
Arbitrary time period from the start of the fuel cell power generation system to the start of power generation, the substitution gas supply unit injects the substitution gas into the fuel gas passage to create the atmosphere of the fuel gas passage. A fuel cell power generation system, wherein the fuel gas is replaced with the replacement gas. 22. The fuel according to claim 21, wherein the replacement gas supply means is a means for bypassing the fuel gas generation means from the raw material supply source and injecting the raw material into the fuel gas passage as the replacement gas. Battery power generation system. 23. A detection value detected by the carbon monoxide concentration detection means, further comprising carbon monoxide concentration detection means for detecting the carbon monoxide concentration contained in the fuel gas generated by the fuel gas generation means. 23. The fuel cell power generation system according to claim 21 or 22, wherein the replacement gas is injected into the fuel gas flow path until the value is below a predetermined value. 24. The fuel cell power generation system according to claim 21, wherein the replacement gas does not contain a sulfur component. 25. The fuel cell power generation system according to claim 21, wherein the raw material supplied from the raw material supply source is a gas obtained by removing sulfur components from city gas. 26. A fuel gas supply step of supplying a fuel gas to the fuel gas flow path of a fuel cell having a fuel gas flow path including a fuel electrode and an oxidant gas flow path including an oxidant electrode; Before at least one of the start of power generation and after the end of power generation, a replacement gas containing a compound containing carbon and hydrogen as a main component is injected into the fuel gas channel to replace the atmosphere of the fuel gas channel with the replacement gas. 1. A fuel cell power generation method comprising a replacement step. 27. A second replacing step of performing the first replacing step after completion of the power generation and then injecting air into the fuel gas passage to replace the atmosphere in the fuel gas passage with the air. The fuel cell power generation method according to claim 26. 28. The fuel gas supply step comprises a fuel gas production step of producing a hydrogen-rich fuel gas as the fuel gas from a raw material containing a compound containing carbon and hydrogen as a main component, and the fuel gas production step in the first substitution step is performed. 27. The fuel cell power generation method according to claim 26, wherein the fuel gas is generated in the fuel gas generating step until the injection of the replacement gas into the fuel gas passage is completed. 29. The fuel gas supplying step includes a fuel gas generating step of generating a hydrogen-rich fuel gas as the fuel gas by a fuel gas generating means from a raw material containing a compound containing carbon and hydrogen as main components. The method further comprises a third replacement step of supplying steam to the gas generating means to replace the atmosphere inside the fuel gas generating means with the steam.
27. The fuel cell power generation method according to claim 26, wherein after the power generation is finished, the fuel gas generation step by the fuel gas generation means is stopped and the third replacement step and the first replacement step are performed. 30. A fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and a fuel gas flow passage including a fuel electrode and an oxidant gas flow including an oxidant electrode. A fuel gas supply step of supplying the fuel gas to the fuel gas passage of a fuel cell having a passage,
A first replacement step of supplying the raw material as a raw material gas directly to the fuel gas flow path to replace the atmosphere of the fuel gas flow path with the raw material gas, before starting power generation of the fuel cell and after ending power generation. A fuel cell power generation method, wherein the first replacement step is performed in at least one of the above. 31. A second replacing step of performing the first replacing step after completion of the power generation, and then injecting air into the fuel gas passage to replace the atmosphere in the fuel gas passage with the air. 31. The fuel cell power generation method according to claim 30. 32. The fuel cell power generation method according to claim 30, wherein the fuel gas is generated in the fuel gas generation step until the injection of the raw material gas into the fuel gas passage in the first replacement step is completed. 33. The fuel gas generation in the fuel gas generation step is performed using a fuel gas generation means, and steam is supplied to the fuel gas generation means to replace the atmosphere inside the fuel gas generation means with the steam. 31. A third replacement step is further provided, wherein after the power generation is completed, the fuel gas generation step by the fuel gas generation means is stopped, and the third replacement step and the first replacement step are performed. The fuel cell power generation method described. 34. A fuel gas producing step of producing a hydrogen-rich fuel gas from a raw material containing a compound containing carbon and hydrogen as main components, and a fuel gas flow passage including a fuel electrode and an oxidant gas flow including an oxidant electrode. A fuel gas supply step of supplying the fuel gas to the fuel gas passage of a fuel cell having a passage,
A first replacement step of injecting a replacement gas containing a compound containing carbon and hydrogen as a main component into the fuel gas flow path to replace the atmosphere of the fuel gas flow path with the replacement gas; A fuel cell power generation method in which the first replacement step is performed for an arbitrary time period from the start of startup to the start of power generation.