JP2003300702A - Method for operating hydrogen-containing gas producing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen-containing gas producing apparatus which can be smoothly operated by improving the activity of a carbon monoxide removing catalyst. <P>SOLUTION: In the method for operating the hydrogen-containing gas producing apparatus provided with at least a reformer 3 for producing the hydrogen- containing gas containing hydrogen by reforming raw materials and fuel, a transformer 4 for transforming carbon monoxide contained in the hydrogen- containing gas to carbon dioxide with a carbon monoxide transforming catalyst, and a carbon monoxide remover 5 for decreasing the concentration of carbon monoxide contained in the hydrogen-containing gas supplied from the transformer 4 after being transformed to equal to or below a prescribed value by using a carbon monoxide removing catalyst 6, a catalyst drying process for drying the carbon monoxide removing catalyst 6 before the transformed hydrogen-containing gas is supplied from the transformer 4 to the carbon monoxide remover 5 in the start-up of the hydrogen-containing gas producing apparatus is included. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating a hydrogen-containing gas generator for generating a hydrogen-containing gas supplied to a fuel cell, and more particularly to a hydrogen-containing gas generator for stopping the generation of the hydrogen-containing gas. The present invention relates to a driving method when starting the vehicle.

[0002]

Fuel cells generate electricity from hydrogen and oxygen, which oxygen can usually be obtained from air and hydrogen can be obtained from gases containing alcohols and hydrocarbons. Here, when hydrogen is obtained from a gas containing hydrocarbon, it is necessary to reform the hydrocarbon into hydrogen using a hydrogen-containing gas generator.

In a typical hydrogen-containing gas generator, a raw fuel supply section for supplying the raw fuel and desulfurization of the raw fuel are provided in a gas path from the supply of the raw fuel containing hydrocarbon to the generation of the hydrogen-containing gas. Desulfurizer for performing desulfurization, reformer for producing hydrogen-containing gas by reacting raw fuel after desulfurization with water, carbon monoxide contained in hydrogen-containing gas is converted to carbon dioxide using a carbon monoxide shift catalyst. By selectively oxidizing carbon monoxide which is present in a small amount in the hydrogen-containing gas that has passed through the transformer and the carbon monoxide transformer (carbon monoxide transformer),
A carbon monoxide remover is provided for further reducing the concentration of carbon monoxide contained in the hydrogen-containing gas.

Here, from the raw fuel supply section, methane (CH
_When city gas containing ₄ ) as the main component is supplied as raw fuel gas, the reforming reaction performed in the reformer is represented by the following chemical reaction formula.

[0005]

[Chemical formula 1] CH ₄ + H ₂ O → 3H ₂ + CO

Specifically, the reforming catalyst provided in the reformer is heated to a temperature at which the reforming reaction is activated, and the raw fuel gas and steam are reacted on the surface of the reforming catalyst. The process is performed. After that, the copper on the transformer
Using a zinc-based or iron-chromium-based carbon monoxide shift catalyst,
A conversion treatment for converting carbon monoxide into carbon dioxide is performed.

Further, in the polymer electrolyte fuel cell,
It is known that the presence of carbon monoxide poisons the electrocatalyst of a fuel cell.To avoid this, the concentration of carbon monoxide contained in the generated hydrogen-containing gas in a trace amount should be specified. A carbon monoxide remover for reducing the concentration to below the concentration has been provided after the transformer.

Specifically, the carbon monoxide remover contains a catalyst layer having a carbon monoxide removing catalyst in which a precious metal such as ruthenium, rhodium, platinum or palladium is carried on a carrier such as alumina. When the hydrogen-containing gas and oxygen (air) are supplied to the catalyst layer to activate the reaction shown in the chemical reaction formula below, carbon monoxide contained in the hydrogen-containing gas is converted into the chemical reaction formula below. As shown in (3), the concentration of carbon monoxide contained in the hydrogen-containing gas is selectively reduced to 10 ppm or less.

[0009]

[Chemical formula 2] 2CO + O ₂ → 2CO ₂

Here, in a fuel cell system comprising a fuel cell and a hydrogen-containing gas generator for generating a hydrogen-containing gas supplied to the fuel cell, when stopping the power generation in the fuel cell, The production of the hydrogen-containing gas performed in the hydrogen-containing gas generator is also stopped. Then, when the operation of the fuel cell is restarted, the operation method is also performed such that the hydrogen-containing gas generation device is simultaneously started. Further, while the operation of the hydrogen-containing gas generator is stopped, the inside of the hydrogen-containing gas generator is replaced with steam.

[0011]

However, since the carbon monoxide removal catalyst provided in the carbon monoxide remover adsorbs water during the steam replacement performed when the hydrogen-containing gas generator is stopped, the above chemical reaction formula is used. There has been a problem that the carbon monoxide removing catalyst does not work effectively in the carbon monoxide removing reaction as shown. Therefore, the fuel cell cannot be operated for several minutes to several tens of minutes until the concentration of carbon monoxide contained in the gas discharged from the carbon monoxide remover falls below a predetermined value. There is a problem that the entire battery system cannot be operated smoothly.

The present invention has been made in view of the above problems, and an object thereof is to increase the activity of a carbon monoxide removing catalyst, thereby producing a hydrogen-containing gas that enables a smooth operation of a fuel cell system. The point is to provide a method of operating the device.

[0013]

The first characteristic configuration of the method for operating a hydrogen-containing gas generator according to the present invention for solving the above-mentioned problems is as set forth in claim 1 of the scope of claims. A reformer for reforming raw fuel to generate hydrogen-containing gas containing hydrogen, and monoxide for converting carbon monoxide contained in the hydrogen-containing gas into carbon dioxide by a carbon monoxide shift catalyst A carbon shift converter and a carbon monoxide remover for reducing the concentration of carbon monoxide contained in the hydrogen-containing gas after the shift treatment supplied from the carbon monoxide shift converter to a predetermined value or less by the carbon monoxide removal catalyst. In a hydrogen-containing gas generation apparatus comprising at least the hydrogen-containing gas after the shift treatment is supplied from the carbon monoxide shift converter to the carbon monoxide remover at the time of starting the hydrogen-containing gas generation apparatus. To In that it includes a catalyst drying step of drying the carbon monoxide removing catalyst.

The second characteristic configuration of the operating method of the hydrogen-containing gas generator according to the present invention for solving the above-mentioned problems is the above-mentioned first characteristic as described in claim 2 of the scope of claims. In addition to the configuration, the carbon monoxide remover is provided with temperature adjusting means capable of adjusting the temperature of the carbon monoxide removing catalyst, and in the catalyst drying step, the carbon monoxide is removed by using the temperature adjusting means. The point is to heat and dry the removed catalyst.

The third characteristic configuration of the operating method of the hydrogen-containing gas generator according to the present invention for solving the above-mentioned problems is the second characteristic as described in claim 3 of the scope of claims. In addition to the configuration, the hydrogen-containing gas generation device comprises at least a nitrogen supplier for supplying nitrogen to the carbon monoxide remover, and in the catalyst drying step, the carbon monoxide remove catalyst is changed to nitrogen. It is exposed and dried.

The fourth characteristic configuration of the operating method of the hydrogen-containing gas generator according to the present invention for solving the above-mentioned problems is to supply raw fuel as described in claim 4 of the scope of claims. A raw fuel supply unit for performing, a steam generator for supplying steam, and a reformer for reforming a mixed gas containing the raw fuel and the steam to generate a hydrogen-containing gas containing hydrogen, Included in the carbon monoxide shift converter for transforming carbon monoxide contained in the hydrogen-containing gas into carbon dioxide by the carbon monoxide shift catalyst, and the hydrogen-containing gas after the shift treatment supplied from the carbon monoxide shift converter. A hydrogen-containing gas generator comprising at least a carbon monoxide remover for reducing the concentration of carbon monoxide to a predetermined value or less by a carbon monoxide remove catalyst, wherein When partially replacing the inside of the hydrogen-containing gas generator, the valve provided in the flow path of the hydrogen-containing gas after the shift treatment between the carbon monoxide shift converter and the carbon monoxide remover is closed. The point is to prevent water vapor from entering the inside of the carbon monoxide remover.

The operation and effect will be described below. According to the first characteristic configuration of the operating method of the hydrogen-containing gas generation device according to the present invention, the hydrogen content after the shift treatment from the carbon monoxide shift converter to the carbon monoxide remover at the time of starting the hydrogen-containing gas generation device. By including a catalyst drying step of drying the carbon monoxide removal catalyst before the gas is supplied, the water adhering to the carbon monoxide removal catalyst is forcibly removed, and the activity as the catalyst is improved. Can be increased. As a result, the selective oxidation of carbon monoxide is promoted, and the time required to reduce the concentration of carbon monoxide can be shortened.

According to the second characteristic configuration of the method for operating the hydrogen-containing gas generating apparatus according to the present invention, the carbon monoxide removing catalyst is heated and dried in the catalyst drying step, whereby the water content from the carbon monoxide removing catalyst is increased. Can be effectively removed.

According to the third characteristic configuration of the method for operating the hydrogen-containing gas generator according to the present invention, the carbon monoxide removing catalyst is exposed to the nitrogen atmosphere in the catalyst drying step by heating (the humidity is very low. Since it is exposed to the atmosphere), it is possible to more effectively remove water from the carbon monoxide removal catalyst.

According to the fourth characteristic configuration of the method for operating the hydrogen-containing gas generator according to the present invention, when the inside of the hydrogen-containing gas generator is partially replaced by steam, the carbon monoxide shift converter and the carbon monoxide shift converter are used. By closing the valve provided between the carbon monoxide remover and the carbon monoxide remover, it is possible to prevent water vapor from entering the carbon monoxide remover. It is possible to avoid the problem.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of a hydrogen-containing gas generator will be described below with reference to the drawings. The hydrogen-containing gas generation device illustrated in FIG. 1 is a device that receives the supply of raw fuel to generate a hydrogen-containing gas and supplies the hydrogen-containing gas to a fuel cell. Therefore, the hydrogen-containing gas generation device reacts the desulfurizer 1 that desulfurizes the raw fuel containing hydrocarbons, the steam generator 2 that vaporizes water to generate steam, and the desulfurized raw fuel gas and steam. Reformer 3 for generating a hydrogen-containing gas, a converter (carbon monoxide converter) 4 for converting carbon monoxide contained in the hydrogen-containing gas into carbon dioxide, and a hydrogen-containing gas passed through the converter 4. And a carbon monoxide remover 5 for selectively oxidizing a small amount of carbon monoxide present therein to further reduce the carbon monoxide concentration contained in the hydrogen-containing gas.

The desulfurizer 1 first desulfurizes the raw fuel gas when city gas containing methane gas (CH ₄ ) as a main component and a sulfur compound added as an odorant is used as the raw fuel gas. Is used to remove the sulfur compound. In this desulfurization treatment, a desulfurization method is used in which hydrogen is added to the raw fuel gas and a hydride obtained by reacting the two with a catalyst is adsorbed on zinc oxide or the like. Hydrogen added to the raw fuel gas for desulfurization may be directly supplied from a separately provided hydrogen tank or may be used by returning the hydrogen-containing gas generated in the reformer 3 to the desulfurizer 1. . The raw fuel gas is not limited to the city gas containing methane as a main component, and gas containing various hydrocarbons such as propane and butane can be used.

The reformer 3 reacts the desulfurized raw fuel gas (methane gas) with the steam supplied from the steam generator 2 by the catalytic action of the reforming catalyst to produce hydrogen containing hydrogen and carbon monoxide. This is a device for generating a contained gas. During this reaction, the reforming catalyst is maintained at a temperature of, for example, 650 ° C. to 750 ° C., and methane gas and steam are reformed according to the following chemical reaction formula to generate a hydrogen-containing gas.

[0024]

[Chemical formula 3] CH ₄ + H ₂ O → 3H ₂ + CO

The shift converter 4 is a device for transforming carbon monoxide contained in the hydrogen-containing gas supplied from the reformer 3 into carbon dioxide. The conversion of carbon monoxide to carbon dioxide is
This is to prevent the deterioration of the electrode that occurs when carbon monoxide is supplied to the fuel cell. At this time, the carbon monoxide shift catalyst for transforming carbon monoxide into carbon dioxide is about 200 ° C.
The carbon monoxide and water vapor are metamorphized by the catalytic action of the carbon monoxide shift catalyst according to the following chemical reaction formula.

[0026]

[Chemical formula 4] CO + H ₂ O → CO ₂ + H ₂

The carbon monoxide remover 5 is a device that selectively oxidizes unreacted carbon monoxide in the shift converter 4 into carbon dioxide, and is thereby included in the hydrogen-containing gas supplied to the fuel cell. The concentration of carbon monoxide generated can be made extremely low. Specifically, the carbon monoxide remover 5 is
A carbon monoxide removing catalyst 6 in which a noble metal such as ruthenium, rhodium, platinum or palladium is supported on a carrier such as alumina, and a temperature adjusting means 7 capable of adjusting the temperature of the carbon monoxide removing catalyst 6. It becomes. Thereby,
The temperature of the carbon monoxide removal catalyst 6 can be adjusted to a temperature at which the selective oxidation reaction of carbon monoxide, which can be represented by the following chemical reaction formula, is activated, and the carbon monoxide contained in the hydrogen-containing gas can be adjusted. Is reduced to less than ten ppm. In addition, the oxygen used for the selective oxidation of carbon monoxide,
Oxygen in the air is used.

[0028]

[Chemical formula 5] 2CO + O ₂ → 2CO ₂

The configuration of the hydrogen-containing gas generator and the method of generating the hydrogen-containing gas have been described above. The operation method of the hydrogen-containing gas generator at startup will be described below.

(First Embodiment) Before the hydrogen-containing gas generator shown in FIG. 1 is started, the valves V1, V2, V3 and V4 are used.
Is closed, and the inside of the hydrogen-containing gas generator is replaced with water vapor, but when the hydrogen-containing gas generator is started, the valve V3 is opened to remove the carbon monoxide remover 5 as described later. A catalyst drying step for drying the carbon monoxide removing catalyst 6 is performed to remove the water adhering to the carbon monoxide removing catalyst 6. Next, the valve V
It is possible to raise the temperature of the reforming catalyst (not shown) of the reformer 3 to a predetermined temperature using a heater (not shown) or the like while opening 2 to allow steam to flow into the hydrogen-containing gas generator. Done. After that, the valve V1 is opened to flow the raw fuel, and the reforming reaction represented by the chemical reaction formula 3 is performed in the reformer 3. After that, carbon monoxide contained in the gas after the reforming treatment is converted into carbon dioxide by the shift converter 4. still,
The opening / closing timing of each valve is described as an example, and the operation of the hydrogen-containing gas generator and the catalyst drying step may be performed at other opening / closing timings.

Next, in the carbon monoxide remover 5 which has been subjected to the catalyst drying step in advance, by selectively oxidizing carbon monoxide contained in the gas after the shift treatment, the carbon monoxide remover 5 is removed. The concentration of carbon monoxide contained in the discharged gas can be reduced to a predetermined value or less.

The above catalyst drying step will be described below. As shown in FIG. 1, the carbon monoxide remover 5 comprises a carbon monoxide removing catalyst 6 and a temperature adjusting means 7 such as an electric heater capable of adjusting the temperature of the carbon monoxide removing catalyst 6. Therefore, by carrying out the step of heating and drying the carbon monoxide removing catalyst 6 as the catalyst drying step, the water adhering to the surface of the carbon monoxide removing catalyst 6 can be removed. The temperature for heating the carbon monoxide removing catalyst 6 is preferably a temperature (100 ° C.) or higher at which water adhering to the surface of the carbon monoxide removing catalyst 6 vaporizes.
However, when the water attached to the carbon monoxide removal catalyst 6 contains impurities, or when the pressure inside the carbon monoxide remover 5 is different from normal pressure, the temperature at which water vaporizes also changes. In order to obtain the carbon monoxide removing catalyst 6 by the temperature adjusting means 7.
The heating temperature of may be adjusted to other values. Furthermore, when the water attached to the surface of the carbon monoxide removal catalyst 6 does not need to be vaporized immediately, the temperature may be 100 ° C. or lower.

Further, in the catalyst drying step, the valve V1,
When V2 is closed and valves V3 and V4 are opened,
After replacing the inside of the carbon monoxide remover 5 with nitrogen and expelling water from the periphery of the carbon monoxide remove catalyst 6 (after exposing the carbon monoxide remove catalyst 6 to an atmosphere having a very low humidity),
The carbon monoxide removing catalyst 6 can be heated and dried to remove the water adhering to its surface.

(Second Embodiment) The hydrogen-containing gas generating apparatus shown in FIG. 2 is different from the hydrogen-containing gas generating apparatus shown in FIG. 1 in the structure of valves and pipes. Therefore, the open / closed state (state of steam substitution) of the valve before starting can be made different from that of the first embodiment.

The state of the steam replacement before starting the hydrogen-containing gas generator shown in FIG. 2 is at least the valves V1 and V.
It is formed by closing four valves of V2, V5 and V6. That is, the interiors of the desulfurizer 1, the reformer 3, and the shift converter 4 are in a state of being replaced with steam. As a result, since the carbon monoxide removal catalyst 6 of the carbon monoxide remover 5 is not arranged in the steam atmosphere, moisture may be attached to the surface of the carbon monoxide removal catalyst 6 while the hydrogen-containing gas generator is stopped. Nothing. The inside of the carbon monoxide remover 5 before the activation of the hydrogen-containing gas generator is closed with valves V3, V5, and V7 and replaced with raw fuel gas or nitrogen gas.

After that, when the hydrogen-containing gas generator is started, first, the valves V2, V3, and V5 are opened to allow the steam to flow into the hydrogen-containing gas generator, and the reforming catalyst of the reformer 3 (not shown). No.) is raised to a predetermined temperature. After that, open the valve V1 and let the raw fuel flow,
In the reformer 3, the reforming reaction represented by the chemical reaction formula 3 is performed. Then, the carbon monoxide contained in the gas after the reforming treatment is converted into carbon dioxide by the converter 4.

Next, in the carbon monoxide remover 5 which was not replaced with steam while the hydrogen-containing gas generator was stopped, carbon monoxide contained in the gas after the shift conversion treatment was selectively oxidized to remove carbon monoxide. The concentration of carbon monoxide contained in the gas discharged from the carbon oxide remover 5 can be reduced to a predetermined value or less. At this time, carbon monoxide remover 5
Since the inside of the carbon monoxide was not replaced with steam, the decrease in the catalytic action due to the water adhering to the surface of the carbon monoxide removal catalyst 6 is not significantly observed.

As in the case described in the first embodiment, the carbon monoxide remover 5 has a temperature of a carbon monoxide removing catalyst 6 and an electric heater capable of adjusting the temperature of the carbon monoxide removing catalyst 6. And adjusting means 7. Therefore, before the start of the hydrogen-containing gas generator, before the hydrogen-containing gas after the conversion treatment is supplied from the shift converter 4 to the carbon monoxide remover 5, the same catalyst drying step as in the first embodiment is performed. By carrying out, the carbon monoxide removal catalyst 6 can be heated and dried to remove the water adhering to the surface thereof.

For example, before starting the hydrogen-containing gas generator,
Close the valves V1, V2, V7, and open the valves V3, V5, V
6 open, or valves V1, V2, V5, V
6 is closed and the valves V3 and V7 are opened, the inside of the carbon monoxide remover 5 is replaced with nitrogen to form a state in which moisture does not exist around the carbon monoxide remove catalyst 6, and The carbon oxide removal catalyst 6 can be heated and dried to remove the moisture adhering to the surface thereof. Further, the carbon monoxide removing catalyst 6 is not replaced with nitrogen inside the carbon monoxide removing device 5.
It suffices to only perform the catalyst drying step by heating.

(Examples) The carbon monoxide concentration contained in the gas discharged from the carbon monoxide remover 5 will be described below with respect to an example in which the catalyst drying step was carried out and a comparative example in which the catalyst drying step was not carried out. The measurement result will be described with reference to FIG.

In the catalyst drying step, which will be described as an example, at least the carbon monoxide removing catalyst 5 is heated by using the temperature control means 7 while flowing nitrogen into the carbon monoxide removing device 5 to perform nitrogen substitution. This is an example when dried. Specifically, the nitrogen flow rate is 4.2 liters (Normal)
In this example, the carbon monoxide removal catalyst 6 is held at about 105 ° C. to dry the catalyst. After carrying out this catalyst drying step, first, as described above, the valve V2
Is opened to allow steam to flow into the hydrogen-containing gas generator, the reforming catalyst of the reformer 3 is heated to a predetermined temperature, and then the valve V1 is opened to flow the raw fuel gas into the reformer 3. By doing so, the reforming reaction is started.

As shown by the solid line in FIG. 3, the carbon monoxide concentration at the outlet of the carbon monoxide remover 5 starts to rise after the reforming reaction is started. Immediately after the start of the reforming reaction, the amount of carbon monoxide flowing into the carbon monoxide remover 5 and the amount of oxygen used in the selective oxidation reaction with carbon monoxide are not set to an appropriate ratio. The carbon monoxide concentration at the outlet of the carbon monoxide remover 5 temporarily becomes a high value, but as the reforming reaction stabilizes, the carbon monoxide concentration at the outlet of the carbon monoxide remover 5 becomes 10 (ppm). It can be seen that the concentration is reduced to the following.

On the other hand, in the comparative example shown by the broken line in FIG. 3, the nitrogen flow rate is 4.2 liters (Norm) before the start of the reforming reaction.
al) / min and the carbon monoxide removal catalyst 6 is maintained at a low temperature of about 65 ° C., and the procedure from the start of the reforming reaction is the same as that of the above-mentioned embodiment. Also in this case, for the same reason as in the example, after the reforming reaction is started, the carbon monoxide concentration at the outlet of the carbon monoxide remover 5 starts to increase. However, the removal of water adhering to the surface of the carbon monoxide removing catalyst 6 (drying of the catalyst) was incomplete, so that the carbon monoxide concentration at the outlet of the carbon monoxide removing device 5 was 10%.
The time required to reach (ppm) or less is long. Since the hydrogen-containing gas cannot be supplied to the fuel cell until the carbon monoxide concentration falls below a predetermined value, it takes a long time to start the fuel cell if the catalyst drying step is not performed. It can be said that

[Brief description of drawings]

FIG. 1 is a configuration diagram of a hydrogen-containing gas generation device.

FIG. 2 is another configuration diagram of the hydrogen-containing gas generation device.

FIG. 3 is a graph showing the change over time in the carbon monoxide concentration at the outlet of the carbon monoxide remover.

[Explanation of symbols]

1 desulfurizer 2 Steam generator 3 reformer 4 Transformer (Carbon monoxide transformer) 5 Carbon monoxide remover (CO remover) 6 Carbon monoxide removal catalyst (CO removal catalyst) 7 Temperature control means

Claims (4)

[Claims] 1. A reformer that reforms a raw fuel to produce a hydrogen-containing gas containing hydrogen, and carbon monoxide contained in the hydrogen-containing gas is converted into carbon dioxide by a carbon monoxide conversion catalyst. A carbon monoxide shift converter to be treated, and carbon monoxide for reducing the concentration of carbon monoxide contained in the hydrogen-containing gas after the shift treatment supplied from the carbon monoxide shift converter to a predetermined value or less by the carbon monoxide removal catalyst. In a hydrogen-containing gas generator comprising at least a scavenger, supply of the hydrogen-containing gas after the shift treatment from the carbon monoxide shift converter to the carbon monoxide scavenger when the hydrogen-containing gas generator is started up. The method for operating a hydrogen-containing gas generation device, comprising a catalyst drying step of drying the carbon monoxide removal catalyst before the above step. 2. The carbon monoxide remover comprises temperature adjusting means capable of adjusting the temperature of the carbon monoxide removing catalyst, and the carbon monoxide is removed by using the temperature adjusting means in the catalyst drying step. The method for operating a hydrogen-containing gas generator according to claim 1, wherein the removal catalyst is dried by heating. 3. The hydrogen-containing gas generation device comprises at least a nitrogen supplier for supplying nitrogen to the carbon monoxide remover, and in the catalyst drying step, the carbon monoxide remove catalyst is changed to nitrogen. The method for operating a hydrogen-containing gas generation apparatus according to claim 2, wherein the method is performed by exposing and drying. 4. A hydrogen-containing hydrogen by carrying out a reforming process of a mixed gas containing the raw fuel and the steam, a raw fuel supply section for supplying the raw fuel, a steam generator for supplying the steam. A reformer that generates a contained gas, a carbon monoxide shifter that shifts carbon monoxide contained in the hydrogen-containing gas into carbon dioxide by a carbon monoxide shift catalyst, and a carbon monoxide shifter are supplied. In the hydrogen-containing gas generator comprising at least a carbon monoxide remover for reducing the concentration of carbon monoxide contained in the hydrogen-containing gas after the shift conversion treatment to a predetermined value or less by the carbon monoxide removing catalyst, the steam generator In the case of partially replacing the inside of the hydrogen-containing gas generation device with water vapor supplied from the hydrogen-containing gas after the shift treatment between the carbon monoxide shift converter and the carbon monoxide remover. Of closing the valve provided in the flow path, the method operation of hydrogen-containing gas generator for preventing the carbon monoxide remover inside the steam entering.