JP3490877B2 - Starting method of reformer for fuel cell - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a partial oxidation reforming reformer for a fuel cell, and more particularly to improvement of a starting method thereof.

[0002]

2. Description of the Related Art In recent years, in the field of a fuel gas reformer for supplying hydrogen to a fuel cell (hereinafter simply referred to as a reformer), hydrocarbon-based raw fuels such as natural gas, city gas and naphtha are used. A so-called steam reforming method is adopted, in which it is mixed with high-temperature steam and reformed into a hydrogen-rich gas by a reforming catalyst. This steam reforming reaction is represented by the reaction formula of the following chemical formula 1 using methane as an example. Since the steam reforming reaction is an endothermic reaction, the reforming catalyst is usually burned at 600 ° C to 800 ° C with a burner.
The reaction proceeds while maintaining a high temperature.

[0003]

[Chemical 1]

As can be seen from the reaction formula, the reformed gas produced in the reaction contains carbon monoxide CO of about ten and several percents. As for fuel cells, this carbon monoxide C
Since O becomes a factor that lowers the catalytic activity of the electrode, actually the generated reformed gas is passed through a CO shifter equipped with a shift catalyst, and carbon monoxide CO in the reformed gas is converted into carbon dioxide C
In many cases, the gas is supplied to the fuel cell after the shift reaction to O ₂ , and there is also a CO selective oxidizer provided downstream of the CO shift converter in order to further reduce the CO concentration.

In contrast to such a steam reforming system, in recent years, a partial oxidation reforming for obtaining a hydrogen-rich reformed gas by partially oxidizing a fuel gas with air and causing a steam reforming reaction with a reforming catalyst A method is known (Japanese Patent Laid-Open No. 7-215702)
Issue). The partial oxidation reaction is represented by the reaction formula of Chemical formula 2 using methane as an example.

[0006]

[Chemical 2]

In this partial oxidation reforming system, the basic structure and operation method of the steam reformer including the steam reforming catalyst can be used as they are. In addition,
Since the reforming catalyst can be heated by the heat generated by the partial oxidation reaction, there is an advantage that the operation can be performed without heating the catalyst layer by the burner unlike the steam reforming method.

[0008]

By the way, in the steam reforming system and the partial oxidation reforming system as described above, at the time of start-up, the reforming catalyst is heated to a high operating temperature, and C
It is necessary to raise the temperature of the O shift converter and the CO selective oxidizer to a predetermined operating temperature. Therefore, in the conventional steam reforming system, the above-mentioned burner was used to heat the reforming catalyst layer at the time of startup, but in the initial stage of startup, the fuel gas was not sent to the catalyst layer, and it was simply boiled or steamed. The reforming catalyst is heated while being fed with an inert gas to raise the temperature of the reforming catalyst, and after the temperature of the reforming catalyst is raised to a certain degree (for example, 500 ° C.), the fuel gas and steam are fed to the reforming catalyst to carry out the reforming reaction. It had a startup method of starting. This is because when the fuel gas is fed into the reforming catalyst layer while being boiled, the hydrocarbons in the gas undergo a decomposition reaction when the catalyst layer reaches a high temperature (400 to 500 ° C.), whereby carbon becomes the reforming catalyst. It is thought that this is due to the fact that it is precipitated.

The starting method of such a steam reforming system is as follows.
Although it is applied to the partial oxidation reforming method as it is, from the viewpoint of simplifying the device configuration as much as possible and achieving efficient temperature rise of the entire device, the above startup method is It is considered that there is room for improvement as a method of starting the reforming method. The present invention has been made based on such a background, and in a partial oxidation reforming type reformer for a fuel cell, it is possible to quickly and effectively raise the temperature of the reforming apparatus as a whole at the time of startup. The purpose is to present a possible startup method.

[0010]

In order to solve the above-mentioned problems, the present invention provides a method for starting a reforming apparatus for a fuel cell of a partial oxidation reforming system, wherein in a first starting step, reforming is performed immediately after starting the starting. Fuel gas is supplied to the catalyst layer of the gas generator,
The fuel gas that has flowed through the catalyst layer and the CO reduction reactor is burned by a burner that heats the catalyst layer, and then in a second starting step, the reformed gas generator is set to a predetermined temperature in the first starting step. After the temperature was raised to the temperature, fuel gas and air were supplied to the catalyst layer of the reformed gas generator, and the gas that had been subjected to the oxidation reaction in the catalyst layer was made to flow to the CO reduction reactor. According to this start-up method, in the first start-up step, the catalyst layer of the reformed gas generator is heated by the heating of the burner, and the CO reduction reactor is also efficiently heated by the fuel gas heated in the catalyst layer. The temperature is raised by heating. In the second start-up step, the temperature of the catalyst layer of the reformed gas generator is raised by the oxidation reaction in the catalyst layer, and the CO reduction reactor is also efficiently heated and raised by the gas heated in the catalyst layer. To be done.
In the first startup step, the catalyst layer does not react, so it can be executed even when the temperature of the catalyst layer is low.
If it continues until it becomes, carbon precipitation will occur. While the second
In the start-up step of, since the reaction is performed in the catalyst layer, low temperature (3
Although it cannot be performed at 00 ° C., carbon precipitation is unlikely to occur even at high temperatures (400 ° C. or higher). Therefore, the first startup step is executed in the initial stage of startup when the temperature of the catalyst layer is low, and the second startup step is performed so that the temperature of the catalyst layer does not become high (400 ° C. or higher). It is possible to prevent the deposition of carbon and efficiently raise the temperature of the catalyst layer and the CO reduction reactor.

Here, the predetermined temperature is a temperature higher than the lowest temperature at which a partial oxidation reaction can occur in the catalyst layer, and a range in which carbon deposition does not occur even if the fuel gas does not react and passes through the catalyst layer. It is set to (300 to 400 ° C.). Further, the present invention may further include at least a part of the reformed gas generator and the CO reduction reactor in a single case, and in the first starting step, both of them may be heated in the case. it can.

Further, the present invention can be characterized in that a burner is provided outside the case, and the air heated by the burner is supplied into the case in the first starting step.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) [Description of Overall Configuration of Fuel Cell System] First, the configuration of a fuel cell system, which is an application example of the present invention, will be described. Figure 1
FIG. 3 is a block diagram of a main configuration of a reformer for the present fuel cell. This fuel cell system uses a reformer to reform a fuel gas such as natural gas, city gas, or naphtha, which is supplied from a fuel gas supply source such as a fuel gas cylinder, into a hydrogen-rich reformed gas. The power generation is performed by the battery 150, and the reformer includes a pump e, a desulfurizer 140, a partial oxidation reformer 105, a CO shift converter 120, and a CO selector in the fuel supply pipe a in order from the source of the fuel gas. An oxidizer 130 and a fuel bypass valve c are sequentially inserted and configured. A start-up burner (hereinafter simply referred to as STB) 104 is installed immediately below the partial oxidation reformer 105, and the STB 104 starts from the fuel bypass valve c.
A fuel bypass pipe b leading to is provided. This is for burning the fuel gas in the STB 104 via the fuel bypass pipe b when the fuel cell system is started, and raising the temperature of the partial oxidation reformer 105 and the like by the combustion heat.

The desulfurizer 140 is for mainly removing organic sulfur compounds (R-SH) contained in fuel such as city gas, and has a cylindrical can structure filled with activated carbon. The fuel gas is desulfurized while flowing through the desulfurizer 140 at room temperature. The partial oxidation reformer 105 has a cylindrical can structure in which a partial oxidation catalyst is filled, and its axial direction is vertical. On the side surface of the cylindrical can, an inlet 109 for fuel gas is provided near the lower end, and an outlet 1 is provided near the upper end.
10 are provided respectively. As a catalyst for the partial oxidation reaction to be filled inside, a honeycomb-shaped alumina porous body on which a platinum-based catalyst such as platinum, palladium, ruthenium, or rhodium is supported, or these catalysts are tablet-shaped. Alternatively, a spherically shaped product is used. Further, a fan f for sending air to the partial oxidation reformer 105 is attached, and an air supply pipe 106 from the fan f is connected to an upstream side of an inlet 109 of the fuel supply pipe a.

The partial oxidation reformer 105 is contained in a case 100 which is slightly larger than this. Partial oxidation reformer 1
The cylindrical can and case 100 of No. 05 is a cylindrical container made of a heat-resistant metal suitable for a partial oxidation reaction and capable of withstanding a high temperature of 500 to 700 ° C., and has a double cylindrical structure. STB104
Is disposed on the bottom plate of the case 100, and the combustion gas thereof flows around the partial oxidation reformer 105 to heat it. At the bottom of the case 100, an inflow pipe 101 for flowing the fuel gas from the fuel bypass pipe b into the STB 104 and a combustion air supply pipe 102 for supplying air from the fan g to the STB 104 are provided, and at the top of the case 100, combustion is performed. An exhaust pipe 103 that discharges air to the outside is arranged.

The CO shift converter 120 has a cylindrical structure filled with a CO shift catalyst, and the reformed gas flows in and out from both end faces thereof. As the CO shift catalyst, specifically, a tablet-shaped copper-zinc catalyst is used. A steam supply pipe 107 for supplying steam is connected to the fuel supply pipe a upstream of the CO shift converter 120. This CO shift converter 120 reduces the CO concentration by transforming carbon monoxide CO contained in the reformed gas with steam, and also produces hydrogen H2 to reform the reformed gas into a more hydrogen-rich one. It has a function of causing it. The CO shift converter 120 is usually a partial oxidation reformer 10.
5, the partial oxidation reformer 10
It is designed so that the high temperature gas of 300 to 400 ° C. sent from No. 5 is diffused inside the CO shift converter 120, the CO shift reaction proceeds while cooling with a temperature gradient, and is sent out as a reformed gas of about 200 ° C. .

The CO selective oxidizer 130 has a structure in which a catalyst for selective oxidation is filled in a cylindrical can. As the selective oxidation catalyst, a catalyst that selectively oxidizes carbon monoxide CO at a temperature of about 100 to 200 ° C. (that is, a catalyst that easily oxidizes carbon monoxide CO and hardly oxidizes hydrogen H ₂ ) is used. It is said to be suitable. Examples thereof include a honeycomb-shaped alumina porous body and an alumina granular carrier, which carry a platinum-based catalyst or a ruthenium-based catalyst, or those which support these catalysts on granular zeolite. C in the fuel supply pipe a
The air suction pipe 10 is provided immediately upstream of the O selective oxidizer 130.
An ejector h for sucking outside air from 8 and mixing the reformed gas is arranged. In this ejector h, an amount of air suitable for the CO selective oxidation reaction (usually several% with respect to the reformed gas) is sucked.

The fuel bypass valve c is a CO selective oxidizer 13
Fuel gas (reformed gas) sent from the fuel cell 1
50 and the STB 104 side are switched and supplied. STB1
When the fuel gas is sent to the 04 side, the fuel gas is supplied to the STB 104 in the case 100 through the fuel bypass pipe b, is burned here, and is used for heating the partial oxidation reformer 105.

The fuel cell 150 is a known phosphoric acid having a structure in which a plurality of unit cells in which a fuel electrode and an air electrode are opposed to each other through an electrolyte matrix impregnated with phosphoric acid are laminated. Type fuel cell. This fuel cell 1
In 50, the hydrogen-rich reformed gas supplied from the fuel supply pipe a is circulated to the fuel electrode side, and the air from the fan (not shown) is circulated to the air electrode side to cause both electrochemical reactions. And generate electricity. The fuel cell 150 is provided with an exhaust pipe d for discharging unreacted reformed gas from the fuel electrode side.

With respect to the above-mentioned various configurations, temperature adjustment of each reactor 105, 120, 130 and fuel cell 150,
Each control such as ignition / extinction of STB, rotation of fans f and g, opening / closing of ejector h, switching of fuel bypass valve c,
This is appropriately performed by a control unit (not shown) provided in the present fuel cell system. [Explanation of Operation During Operation of This Fuel Cell System] FIG. 2
FIG. 3 is a temperature rise characteristic diagram of the fuel cell system in which the vertical axis represents temperature (° C.) and the horizontal axis represents elapsed time (min) from start, which relates to the present embodiment (present invention) and the conventional one. Examples and examples are also listed. In the figure, the solid curve I
To III represent the temperature rising characteristics of the partial oxidation reformer, the CO shift converter 120, and the CO selective oxidizer 130 in the present embodiment, respectively. Further, the dashed-dotted curves IV and V represent the temperature rising characteristics of the CO shifter, the CO selective oxidizer, etc. in the conventional example, respectively. In the figure, the temperature rising characteristics of the conventional partial oxidation reformer are almost the same as the curves of the embodiment, and are therefore omitted. In addition, the fuel cell system is assumed to be initially at room temperature.

At the time of start-up, the pump e is first driven and the fuel bypass valve c is set on the fuel bypass pipe b side under the instruction of the control unit of the present fuel cell system. As a result, the fuel gas is passed through the fuel supply pipe a,
After being treated by the desulfurizer 140, the partial oxidation reformer 105, the CO shift converter 120, and the CO selective oxidizer 1 in the case 100 are treated.
30 in sequence. Then, the fuel is delivered from the fuel bypass valve c to the fuel bypass pipe b, and the inflow pipe 10 of the case 100 is sent.
1 to reach the STB 104. Here, the fuel gas is mixed with the air supplied from the combustion air supply pipe 102 and burned, and the high temperature combustion gas passes through the periphery of the partial oxidation reformer 105 in the case 100 and is partially oxidized and reformed 105. Is heated and exhausted from the exhaust pipe 103 to the outside of the case 100. Thus, the heat of combustion in STB 104 is used to raise the temperature of partial oxidation reformer 105.

Further, the fuel gas continuously supplied to the fuel supply pipe a is heated by the STB 104 while passing through the inside of the partial oxidation reformer 105 where the temperature rises, and is arranged downstream thereof. After flowing through the CO shift converter 120 and the CO selective oxidizer 130, the CO gas passes through the fuel bypass pipe b and is used as STB fuel.
The shift converter 120 and the CO selective oxidizer 130 are also heated and heated.

As shown in the figure, the partial oxidation reformer 105
When the internal temperature of the reformer 105 reaches a predetermined temperature (curve I, after about 10 minutes have elapsed), the fan f is driven according to an instruction from the control unit. This predetermined temperature is set around the minimum temperature considered necessary for causing the partial oxidation reaction, and is about 400 ° C. in FIG. As a result, the supply of air from the air supply pipe 106 is started, and the partial oxidation reaction is started. When the partial oxidation reaction occurs, while the fuel gas mixed with air passes through the inside of the partial oxidation reformer 105, taking methane in the fuel gas as an example, the partial oxidation reaction represented by the reaction formula of the above chemical formula 2 Together with the above
The complete combustion reaction as shown in the reaction formula of (3) also occurs to some extent.

[0024]

[Chemical 3]

This partial oxidation reaction and complete combustion reaction are
Since both are exothermic reactions, the high temperature mixed gas in which hydrogen H ₂ , carbon monoxide CO, carbon dioxide CO ₂ , steam, etc. are mixed from the partial oxidation reformer 105, becomes a CO shift converter 12.
0, and is further sent to the CO selective oxidizer 130, where they are heated and raised in temperature. The steam is supplied from the steam supply pipe 107 at a predetermined temperature (2
When the temperature reaches (00 ° C), it is started according to the instruction of the control system. In the example of FIG. 2, the supply of steam is started almost at the same time as the driving of the fan f is started.

Air is supplied from the air suction pipe 108 at a predetermined temperature (13) at which the CO selective oxidizer 130 can react.
When it reaches 0 ° C.), it is started according to the instruction of the control system. In the example of FIG. 2, air supply is started from the air suction pipe 108 about 2 minutes after the start of steam supply. When air is supplied to the CO selective oxidizer 130 from the air suction pipe 108, the CO selective oxidation reaction is started.

When the temperature of the CO selective oxidizer 130 reaches a predetermined temperature (200 ° C. in FIG. 2), the control unit raises the temperature of the partial reformer 105, the CO shift converter 120, the CO selective oxidizer 130, and the like. Assuming that the reformed gas generation system is in place (hydrogen-rich reformed gas with low CO concentration is generated), the reformer is stopped, and the fuel bypass valve c is set to the fuel cell 150. Then, the reformed gas is supplied to the fuel cell 150.

In the state in which the reformed gas generation system is prepared in this way, the partial oxidation reformer 105 is at a high temperature of 500 ° C. or higher, and in the partial oxidation reformer 105, the partial oxidation reformer 105 is parallel to the partial oxidation reaction. Then, steam reforming reaction due to steam generated by complete combustion (formula 3 above) also occurs. Also CO
The mixed gas passing through the transformer 120 has a relatively high temperature (about 3
The equilibrium reaction shown in Chemical formula 4 is rapidly achieved on the inlet side (00 ° C), and on the outlet side at a relatively low temperature (about 200 ° C),
The equilibrium reaction of Chemical formula 4 moves to the right (Le Chatelier's law). By controlling the reaction applying such a temperature gradient,
The CO concentration in the reformed gas sent from the CO shift converter 120 is reduced to a constant level (about 10,000 ppm).

[0029]

[Chemical 4]

Further, in the CO selective oxidizer 130, the CO selective oxidation reaction shown in Chemical formula 5 mainly occurs, so that the CO concentration in the reformed gas is further reduced (to about 100 ppm).

[0031]

[Chemical 5]

When the supply of the reformed gas to the fuel cell 150 is started, the reformed gas is supplied to the fuel electrode (anode) not shown in the fuel cell 150. At the same time, according to an instruction from the control unit, air is supplied to an air electrode (cathode) not shown, and power generation is started. The remaining reformed gas used for power generation passes through the exhaust pipe d and is discharged to the outside.

The conventional reformer shown as an example in FIG. 2 has the same structure as the reformer in the first embodiment shown in FIG.
A fuel supply pipe for STB for directly supplying the fuel gas to B is provided. Then, at the time of startup, first, the fuel is circulated only through this STB fuel supply pipe and burned in the STB to raise the temperature of the partial oxidation reformer. After the partial oxidation reformer reaches a predetermined temperature (about 400 ° C.), the fuel gas is circulated from the fuel supply pipe a into the partial oxidation reformer, as in the case of the present embodiment. Air is supplied from the fan f to start the reforming reaction.

As shown in FIG. 2, in the conventional example, it took about 20 minutes to start the power generation of the fuel cell 150, but according to the present embodiment, about 12, 3
You can see that power generation can be started in minutes. Further, according to the method for starting the reforming apparatus of the present embodiment, since the partial oxidation reaction is started at the above-mentioned predetermined temperature (about 400 ° C.), the partial oxidation at a high temperature of 400 ° C. remains without the fuel gas reacting. Since it does not flow through the catalyst layer, it is possible to avoid carbon deposition in the partial oxidation catalyst layer.

Although not shown, including this embodiment,
In the following embodiments, the case 100, the CO shifter 120, the CO selective oxidizer 130, the fuel cell 150, etc. arranged outside the case 100 are connected to the fuel supply pipe a and the fuel bypass pipe b. It is assumed that they are connected by a coupler. This allows each coupler to be removed and carried separately. Further, by using, for example, a U-shaped pipe or an L-shaped pipe in combination as the pipes a and b, the arrangement of each reactor can be freely changed, and the shape of the system can be made compact according to the installation environment. .

(Second Embodiment) FIG. 3 is a block diagram showing the main configuration of a fuel cell reforming apparatus according to the present embodiment. In the figure, the same components as those in the first embodiment are designated by the same reference numerals, and common configurations are omitted. The reforming apparatus for a fuel cell according to the present embodiment has substantially the same configuration as that of the first embodiment, except that the partial oxidation reformer 105 and the CO shift converter 120 are arranged in the case 100. Is different.

According to this structure, the CO transformer is also kept warm by the air trapped in the case 100. Further, the starting method of the present system is the same as that of the first embodiment, but when the fuel gas flows through the fuel supply pipe a and the fuel bypass pipe b at the time of starting and is burned in the STB 104,
The combustion gas generated by the STB 104 is the partial oxidation reformer 1
It flows through the periphery of the CO shift converter 120 together with 05 to heat these from the outside. That is, the CO transformer 120 is
Since the gas heated in the partial oxidation reformer 105 is used as the heating medium from the inside as well as from the outside, the temperature is raised more rapidly. Therefore, by this, the timing of the start of the CO shift reaction can be advanced and the power generation preparation system can be promptly taken.

(Embodiment 3) FIG. 4 is a block diagram showing the main structure of a reformer for a fuel cell according to this embodiment. In the reformer for a fuel cell according to the third embodiment, as a modification of the above-described second embodiment, the CO selective oxidizer 130 is arranged inside the case 100 together with the partial oxidation reformer 105 and the CO shift converter 120. ing.

According to this structure, the fuel gas flows through the fuel supply pipe a and the fuel bypass pipe b at the time of startup and the STB1
When the combustion starts in 04, due to the heat retaining effect of the case 100 and the combustion heat of the fuel gas burned in the STB 104,
The CO selective oxidizer 130 can also be heated and heated from both inside and outside. That is, the partial oxidation reformer 105, C
It is possible to raise the temperature of the O shifter 120 and the CO selective oxidizer 130 in a well-balanced manner. As a result, the reformer can be started up quickly.

(Embodiment 4) FIG. 5 is a block diagram showing the main structure of a reformer for a fuel cell according to this embodiment. In the reformer for a fuel cell according to the present embodiment, the partial oxidation reformer 105 and the CO shifter 120 are arranged inside the case 100 as in the second embodiment, but the STB 160 is different from the case 100. Externally, it is provided inside the case 170 together with the coil pipe 180 for heat exchange. This coil pipe 180 is STB160
Of the coil pipe 180 is provided with a pipe for sending air from a fan (not shown) to the inlet side of the coil pipe 180, and a heat transfer supply pipe i is provided from the outlet side of the coil pipe 180 to the bottom of the case 100. .

According to this structure, the fuel gas passes through the fuel supply pipe a and the fuel bypass pipe b at the time of start-up to the STB.
It is fed to 160, where it is burned. Then, the combustion heat is transferred to the air flowing through the coil pipe 180 in the case 170, and the high-temperature air is circulated into the case 100 via the heat transfer air supply pipe i to be partially oxidized. Both the reformer 105 and the CO shifter 120 are heated. In this embodiment, the external STB 160 is the case 1
Since it is stored in a case 170 separate from 00,
The size of the case 100 can be made smaller than that in the second embodiment, and the partial oxidation reformer 105 and the S
It can be carried separately from the TB160. In the present embodiment, the exhaust pipe d is connected to the STB 160,
The unreacted reformed gas discharged from the fuel cell 150 is ST
It is designed to be burned at B160.

Further, in the above-described embodiment, the fuel bypass pipe b is shown in the block diagram (FIGS. 1, 3, 4, 5) showing the main configuration below the apparatus of the case 100 or the case 170, but it goes without saying. However, in order to prevent the position of the pipes from actually causing a problem when the device is installed, it is possible to arrange the pipes along the side surface of the case 100 so as to slightly change the positions of the respective pipes.

Furthermore, in the above embodiment,
Although the case where the fuel cell 150 is of the phosphoric acid type is shown, it can be similarly applied to the case of the solid polymer type.
Further, in the above embodiment, an example in which the reformer is equipped with the CO shift converter 120 and the CO selective oxidizer 130 as the CO reduction reactor is shown. However, in the case where only the CO shift converter is provided. Alternatively, the starting method of the present invention can be applied even when only the CO selective oxidizer is provided.
Has the same effect.

In addition, in the above embodiment, an example in which the partial oxidation reformer 105 is heated up to about 400 ° C. and then the air is mixed with the fuel gas to start the partial oxidation reaction has been described. Air is mixed with fuel gas before the reaction is started, and the partial oxidation reformer 10 is heated to about 300 ° C.
The partial oxidation reaction may naturally start when the temperature of 5 is raised.

[0045]

As is apparent from the above, the present invention is a method for starting a reforming apparatus for a fuel cell, in which a fuel gas is supplied to a catalyst layer of a reformed gas generator so that the catalyst layer and CO
A first starting step of burning the fuel gas flowing through the reducing reactor with the burner, and after the reformed gas generator is heated to a predetermined temperature in the first starting step,
A second starting step of supplying fuel gas and air to the catalyst layer of the reformed gas generator and causing the gas oxidized in the catalyst layer to flow to the CO reduction reactor is provided. It is possible to efficiently raise the temperature of the CO shift converter and the CO selective oxidizer, which are arranged on the downstream side together with the quality control device, and there is an effect that the start-up time is shortened as compared with the conventional case. In addition, it is not necessary to use a special heat medium such as a high temperature inert gas, and carbon deposition on the catalyst layer can be avoided. In addition, the number of piping for fuel supply to the start-up burner can be reduced as compared with the conventional one, and the piping configuration of the system can be simplified.

[Brief description of drawings]

FIG. 1 is a block diagram of a main configuration centering on a reformer for a fuel cell which is an application example of the present invention.

FIG. 2 is a temperature rise characteristic diagram of a reformer for a fuel cell.

FIG. 3 is a block diagram of a main configuration centering on a reformer for a fuel cell, which is an application example of the present invention.

FIG. 4 is a block diagram of a main configuration centering on a reformer for a fuel cell which is an application example of the present invention.

FIG. 5 is a block diagram of a main configuration centering on a reformer for a fuel cell that is an application example of the present invention.

[Explanation of symbols]

100 cases 104, 160 Startup burner 105 Partial oxidation reformer 106, 108 Air supply pipe 107 Steam supply pipe 120 CO transformer 130 CO selective oxidizer 140 desulfurizer 150 phosphoric acid fuel cell 170 heat exchanger a Fuel supply pipe b Fuel bypass pipe c Fuel bypass valve f, g fan h ejector

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01M 8/04-8/06

Claims (3)

(57) [Claims] 1. A reformed gas generator for producing a reformed gas containing hydrogen as a main component by mixing a fuel gas with air, passing through a catalyst layer to partially oxidize and steam reforming, and a reformed gas. A CO-reducing reactor that reduces the concentration of CO in the reformed gas generated by the generator, and a burner that heats the catalyst layer of the reformed gas generator, and a hydrogen-rich reformed gas for a fuel cell. A method of starting a reforming apparatus for a fuel cell, comprising supplying a fuel gas to the catalyst layer, and burning the fuel gas flowing through the catalyst layer and a CO reduction reactor in the burner. After the catalyst layer is heated to 300 to 400 ° C. in the starting step and the first starting step, fuel gas and air are supplied to the catalyst layer to cause an oxidation reaction and a steam reforming reaction in the catalyst layer. Low CO gas The circulating to use the reactor 2
The method for starting a reformer for a fuel cell, comprising: Includes a wherein said reformed gas generator, before Symbol a case for enclosing at least a portion of the CO reduction reactor, a burner provided inside of the case, wherein the first activation step in, the combustion of the burner, the reforming gas generator of the catalyst layer, prior SL CO reduction reactor at least a portion and is characterized by increasing the temperature according to claim 1 reformer according How to start the device. Comprising a wherein the reformed gas generator, before Symbol a case for enclosing at least a portion of the CO reduction reactor, a burner provided outside of the case, wherein the first activation step in, by supplying air heated by the burner within the case, wherein the catalyst layer of the reformed gas generator, that is heated and at least a portion of the pre-Symbol CO reduction reactor The method for starting the reformer for a fuel cell according to claim 1.