JP2003272691A - Fuel cell generating device and operating method of fuel cell generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell generating device that suppresses poisoning by sulfur or the like even if a petroleum liquid fuel is used as a fuel and enables to continue generating operation for a long life cycle, and an operating method of the fuel cell generating device. <P>SOLUTION: The fuel cell generating device comprises a fuel treating system 3 and a fuel cell unit 4, and after reforming the fuel into hydrogen by a reformer of the fuel treating system 3 and reforming carbon monoxide contained in the reformed hydrogen into carbon dioxide by a CO remover 10, carries out generation operation by the fuel cell unit 4. The reformer comprises a petroleum liquid-fuel supply system 1 for supplying the petroleum liquid-fuel and a hydrocarbon fuel-gas supply system 2 for supplying hydrocarbon fuel-gas. <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 generator using a petroleum liquid fuel such as kerosene as a raw fuel and a method for operating the fuel cell power generator.

[0002]

2. Description of the Related Art In recent years, fuel cell power generators have been attracting attention as energy conversion devices for converting fuel into electric power.

Several types of this fuel cell power generator are in operation or under research and development. Among them, a solid polymer fuel cell using a solid polymer membrane as an electrolyte has a compact structure and high output. Since it has a high density and can be operated by a simple system, it is in the spotlight as a power source for not only stationary distributed power sources but also a wide range of industrial fields such as space, vehicles, and households.

Further, the fuel cell power generator is being developed for application to a so-called cogeneration field, which makes good use of heat generated during an electrochemical reaction.

As described above, the fuel cell power generators, which have a high degree of expectation for social life, are roughly divided into a structure including a fuel cell body and a fuel processing system.

The fuel cell main body comprises a membrane electrode assembly in which a proton conductive solid polymer membrane is sandwiched between gas diffusion electrodes covering a catalyst, and gas permeation grooves provided on both outer sides thereof with gas supply grooves as current collectors. A battery stack is configured by alternately arranging separators made of a material having low property in a laminated shape.

Further, the gas diffusion electrode has a fuel electrode on one side and an air electrode (oxidant electrode) on the other side, and the reformed gas containing hydrogen as a main component and air form the gas supply groove of the separator. They are separately supplied via

On the other hand, the fuel processing system is equipped with a desulfurizer, a reformer, a shift reactor, a carbon monoxide remover, etc., using city gas, natural gas, methanol, etc. as a raw fuel, and sulfur contained in the fuel. After being removed by using a desulfurizer, a hydrocarbon fuel is steam-reformed into a reformed gas containing hydrogen as a main component by a chemical reaction using a catalyst in a reformer to add, for example, steam.

The reformed gas steam reformed by the reformer includes
Since it contains a large amount of carbon monoxide (CO), it poisons the catalyst of the fuel cell main body and the like, which is a cause of performance deterioration or accident occurrence.

Therefore, in the fuel processing system, carbon monoxide in the reformed gas subjected to steam reforming is converted into carbon dioxide by the catalysts of the shift reactor and the carbon monoxide remover and supplied to the fuel cell main body. , And electrochemically reacted here, and the direct current power generated at that time was taken out.

As described above, the fuel cell power generation device skillfully uses clean energy and generates electric power by an electrochemical reaction, so that further development is expected as a power generation device without environmental pollution. ing.

[0012]

Fuel cell power generators for stationary distributed power sources, which have been recently developed, generate electric power by using hydrogen as a raw fuel for steam reforming from a gaseous fuel such as city gas or propane gas. There are many cases where

As the raw fuel for automobiles, pure hydrogen to be filled in a cylinder or the like is used in addition to liquid fuel such as gasoline and methanol.

However, gas fuels such as city gas and liquid fuels such as gasoline cause unit price per calorific value, solidification of facilities such as measures for safety and storability, and cost increase due to safety. Recently, application of petroleum-based liquid fuel such as kerosene has been studied as raw fuel in consideration of cost reduction.

In order to supply the raw fuel to the fuel cell, a desulfurization device for removing sulfur contained in the raw fuel is required.

This desulfurization apparatus has an adsorption desulfurization system and a hydrodesulfurization system, but since kerosene as a raw fuel contains 30 to 50 ppm or more of sulfur, which is larger than that of gaseous fuel, it is an adsorption system. The desulfurization method has some concerns when considering the desulfurization efficiency, cost and life cycle. Therefore, the hydrodesulfurization method is suitable for a kerosene desulfurization device, but since the hydrodesulfurization method requires hydrogen, if the supply of hydrogen to the desulfurization device inlet is cut off at startup, Can not be. For this reason, there is a problem that the catalysts incorporated in various devices of the fuel cell are poisoned and the power generation operation is disturbed.

The present invention has been made under such circumstances, and even if a petroleum-based liquid fuel such as kerosene is used, poisoning due to sulfur of a catalyst or the like incorporated in each device is suppressed and life is reduced. An object of the present invention is to provide a fuel cell power generation device that enables long-cycle operation and a method for operating the fuel cell power generation device.

[0018]

In order to achieve the above-mentioned object, a fuel cell power generator according to the present invention is provided with a fuel processing system and a fuel cell main body as described in claim 1. Fuel cell power generation in which the fuel is reformed into hydrogen by the system reformer, carbon monoxide contained in the reformed hydrogen is converted into carbon dioxide by the CO remover, and then the fuel cell main body performs power generation operation In the apparatus, the reformer includes a petroleum-based liquid fuel supply system for supplying a petroleum-based liquid fuel and a hydrocarbon-based gas fuel supply system for supplying a hydrocarbon-based gas fuel.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above object, as described in claim 2, the petroleum-based liquid fuel supply system includes an evaporator and a hydrodesulfurizer.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above-mentioned object, as described in claim 3, the hydrodesulfurizer is a feedback system for returning the reformed gas from either the CO shifter outlet or the CO remover outlet of the fuel processing system. It is equipped with.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above-mentioned object, as described in claim 4, the hydrocarbon-based gas fuel supply system includes an adsorption desulfurizer.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above-mentioned object, as described in claim 5, the petroleum-based liquid fuel supply system is connected to a hydrocarbon-based gas fuel supply system from the middle, and the hydrodesulfurization is connected in series to the downstream side thereof. It is equipped with a vessel and an adsorption type desulfurizer.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above-mentioned object, as described in claim 6, the reformer is a steam reformer.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above-mentioned object, as described in claim 7, the reformer is an autothermal reformer.

Further, the fuel cell power generator according to the present invention is
In order to achieve the above object, as described in claim 8, the reformer is a partial oxidation reformer.

Further, in order to achieve the above-mentioned object, the method for operating a fuel cell power generator according to the present invention, as set forth in claim 9, is characterized in that during start-up operation, carbonization from a hydrocarbon gas fuel supply system is performed. Hydrogen-based gas fuel is supplied to the reformer of the fuel processing system, and part of the hydrogen obtained in the fuel processing system is recycled and supplied to the inlet of the hydrodesulfurizer, and the hydrogen concentration in the inlet gas of the hydrodesulfurizer and When the temperature of the packed bed of desulfurization agent reaches the range where it can function sufficiently, the petroleum-based liquid fuel supply system is switched to the petroleum-based liquid fuel, and after desulfurization of the petroleum-based liquid fuel, the petroleum-based liquid fuel is reformed to hydrogen. This is an operating method in which the fuel cell main body is operated to generate electric power using the reformed hydrogen.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a fuel cell power generator and an operating method of the fuel cell power generator according to the present invention will be described with reference to the drawings and the reference numerals attached to the drawings.

FIG. 1 is a schematic system diagram showing a first embodiment of a fuel cell power generator according to the present invention.

The fuel cell power generator according to this embodiment is supplied from one of a petroleum-based liquid fuel supply system 1 such as kerosene, a hydrocarbon-based gas fuel supply system 2, and each of the systems 1 and 2. Generated from the fuel processing system 3 that processes the generated carbon monoxide and the reformed gas from the fuel processing system 3 by adding oxygen in the air to cause a chemical reaction. And a fuel cell main body 4 for extracting direct current power.

The petroleum liquid fuel supply system 1 is provided with an evaporator 5 and a hydrodesulfurizer 6, and a raw fuel OL such as kerosene is evaporated by the evaporator 5 into a gas, and the gas is supplied to the hydrodesulfurizer 6. The catalyst and hydrogen from the feedback system 8 are reacted with hydrogen sulfide,
The sulfur contained in the raw fuel OL is removed.

Further, the hydrocarbon-based gas fuel supply system 2 is provided with an adsorption type desulfurizer 7 and is equipped with a gas fuel GFUL such as hydrocarbon-based hydrogen.
The sulfur is adsorbed by an adsorbent of the adsorption desulfurizer 7, for example, activated carbon.

On the other hand, the fuel processing system 3 includes a steam reformer 9,
CO transformer 10, CO remover 11, feedback system 8
And adding water vapor to the fuel gas supplied from one of the petroleum-based liquid fuel supply system 1 and the hydrocarbon-based gas fuel supply system 2 to, for example, about 600 ° C. to 700 ° C.
It is reformed into hydrogen gas or the like by the steam reformer 9 maintained at a temperature of around ℃.

The reformed gas reformed by the steam reformer 9 is
The CO concentration is suppressed to a low level by the CO shift converter 10, and CO is further reacted with oxygen in the atmosphere by the CO remover 11, thereby C
It is converted into O ₂ and becomes a reformed gas with a lower CO concentration. Part of this reformed gas is supplied to the hydrodesulfurizer 6 via the feedback system 8 and the rest is supplied to the fuel cell main body 4.
The reformed gas fed back to the hydrodesulfurizer 6 may be the outlet gas of the CO remover 11 or the outlet gas of the CO shift converter 10 as shown in FIG.

The fuel cell body 4 contains hydrogen gas contained in the reformed gas supplied from the fuel processing system 3 to a fuel electrode (not shown),
Oxygen gas contained in the air supplied from the outside to the oxidizer electrode (not shown) is chemically reacted, and the DC power generated at that time is taken out, while unreacted reformed gas is recovered in the fuel recovery system. It is recovered by the steam reformer 9 via 12 and utilized as an endothermic heating source for steam reforming.

A method of operating the fuel cell power generator having such a configuration will be described.

In the operating method of the fuel cell power generator according to the present embodiment, during the start-up operation, the fuel gas GFUL from the hydrocarbon-based gas fuel supply system 2 is operated, and a part of the hydrogen obtained in the fuel processing system is When it is recycled and supplied to the inlet of the hydrodesulfurizer, and when the hydrogen concentration in the inlet gas of the hydrodesulfurizer and the temperature of the desulfurizing agent packed bed are in a temperature range in which the hydrogen desulfurizer sufficiently functions, the petroleum-based liquid fuel supply system 1 is switched to, The fuel cell main body 4 is caused to perform a power generation operation with the raw fuel OL from the petroleum-based liquid fuel supply system 1.

Now, a method of operating the fuel cell power generator according to this embodiment will be described in more detail with reference to FIG.

In the fuel cell power generation plant, when an operation command is input (STEP 1), the temperature of each device is raised by the combustion burner or the electric heater provided in the fuel processing system 3 (STE).
P2).

When the steam reformer 9 reaches a temperature range in which the steam reforming operation can be performed (STEP 3), the fuel cell power plant supplies the gas fuel GFUL such as a hydrocarbon system to the adsorption desulfurizer 7 (STEP 4). Here, for example, after adsorbing sulfur to activated carbon or the like, steam is added, the raw fuel OL is steam-reformed by the steam reformer 9, and carbon monoxide is converted into carbon dioxide by the CO shift converter 10 and the CO remover 11. Then, the fuel cell main body 4 performs power generation operation (STEP 5).

During the power generation operation, unreacted hydrogen gas and the like emitted from the fuel cell main body 4 is recovered as combustion fuel in the steam reformer 9 through the fuel recovery system 12.

During the power generation operation, part of the reformed gas GFUL emitted from the CO remover 11 is supplied (recycled) to the hydrodesulfurizer 6 via the feedback system 8 (STE).
P5).

When the condition for the hydrodesulfurizer 6 to function sufficiently is satisfied (STEP 6), the fuel cell power plant supplies the raw fuel OL from the petroleum-based liquid fuel supply system 1 to the hydrodesulfurizer 6 (STEP 7). ), The recycled hydrogen from the feedback system 8 and the catalyst are reacted with hydrogen sulfide to remove sulfur, steam is added to the raw fuel OL and steam reformed by the steam reformer 9, and the CO shift converter 10 and The carbon monoxide in the raw fuel OL steam-reformed by the CO remover 11 is converted into carbon dioxide, and the fuel cell main body 4 is caused to perform power generation operation (STEP 9).

At this time, the gas fuel GFUL supplied from the hydrocarbon-based gas fuel supply system 2 to the steam reformer 9 via the adsorption desulfurizer 7 while securing the amount of hydrogen gas required for power generation is It is cut (STEP8).

When the fuel cell power generation plant stops the power generation of the fuel cell main body 4 (STEP 11), the fuel supply to the steam reformer 9 is cut off.

During the power generation operation, the fuel cell power generation plant receives a fuel switching command (STEP 10) from the petroleum-based liquid fuel to the hydrocarbon-based gas fuel, the steam reformer from the hydrocarbon-based gas fuel supply system 2 Gas fuel GFUL is supplied to 9, and power generation operation is performed with this gas fuel GFUL (STEP 5, STEP 9).

As described above, the present embodiment is
Steam reformer 9 using hydrocarbon gas fuel GFUL
Steam reforming, and supplying a part of the reformed gas GFUL after steam reforming to the hydrodesulfurizer 6 and satisfying the condition that the hydrodesulfurizer 6 sufficiently functions, a petroleum liquid fuel such as kerosene. After the sulfur is removed by the hydrodesulfurizer 6, the fuel cell main body 4 performs the power generation operation, so that it is possible to perform the low-cost power generation operation without poisoning the catalyst and the like, and the power generation with a long life cycle. You can drive.

In this embodiment, when the power generation operation is performed,
Switching from hydrocarbon gas fuel GFUL to petroleum liquid fuel OL such as kerosene, and further hydrocarbon gas fuel G
The sulfur contained in FUL is treated by the adsorption desulfurizer 7, the sulfur contained in the petroleum liquid fuel OL is treated by the hydrodesulfurizer 6, and the adsorption desulfurizer 7 and the hydrodesulfurizer 6 are separately arranged. However, not limited to this example, for example, as shown in FIG.
Hydrocarbon-based gas fuel supply system 2 is connected in the middle of petroleum-based liquid fuel supply system 1, and hydrodesulfurizer 6 for connecting the hydrodesulfurization agent connected in series to the downstream side thereof and adsorption for adsorbing the desulfurization agent The desulfurizer 7 may be connected in series and provided.

Further, in the present embodiment, the steam reformer 9 is applied when reforming the fuel, but the present invention is not limited to this example, and for example, as shown in FIG. The thermal reformer 13 or, as shown in FIG. 5, a partial oxidation reformer 14 may be applied to reform the fuel. The autothermal reformer 13 does not require fuel for the reforming burner, and the partial oxidation reformer 14 has a compact structure, which is effective.

[0049]

As described above, the fuel cell power generator and the method of operating the fuel cell power generator according to the present invention are configured such that, at the time of start-up operation, a hydrocarbon-based gas fuel is used to reform hydrogen and hydrogenate it. When the desulfurizer 6 satisfies the condition of sufficiently functioning, it is switched to petroleum-based liquid fuel, sulfur is removed, reformed to hydrogen, and power generation operation is performed in the fuel cell main body. It is possible to perform stable operation that does not exist, and to perform power generation operation with a long life cycle.

[Brief description of drawings]

FIG. 1 is a schematic system diagram showing a first embodiment of a fuel cell power generator according to the present invention.

FIG. 2 is a flow diagram used to explain a method of operating a fuel cell power generator according to the present invention.

FIG. 3 is a schematic system diagram showing a second embodiment of a fuel cell power generator according to the present invention.

FIG. 4 is a schematic system diagram showing a third embodiment of a fuel cell power generator according to the present invention.

FIG. 5 is a schematic system diagram showing a fourth embodiment of a fuel cell power generator according to the present invention.

[Explanation of symbols]

1 Petroleum liquid fuel supply system 2 Hydrocarbon gas fuel supply system 3 Fuel processing system 4 Fuel cell body 5 evaporator 6 Hydrodesulfurizer 7 Adsorption desulfurizer 8 Feedback system 9 Steam reformer 10 CO transformer 11 CO remover 12 Fuel recovery system 13 Auto thermal reformer 14 Partial oxidation reformer

Continued front page    F-term (reference) 4G140 EA03 EA06 EA07 EB01 EB03                       EB31 EB32 EB35 EB42 EB43                 5H026 AA06                 5H027 AA06 BA01 BA16 BA17 KK31                       KK41 MM12

Claims (9)

[Claims] 1. A fuel treatment system and a fuel cell main body, wherein a fuel is reformed into hydrogen by a reformer of the fuel treatment system, and carbon monoxide contained in the reformed hydrogen is removed by a CO shift converter and CO. In the fuel cell power generation device that performs power generation operation in the fuel cell main body after converting into carbon dioxide in the reactor, the reformer is a petroleum-based liquid fuel supply system that supplies petroleum-based liquid fuel,
A fuel cell power generation device comprising: a hydrocarbon gas fuel supply system for supplying a hydrocarbon gas fuel. 2. The fuel cell power generator according to claim 1, wherein the petroleum liquid fuel supply system includes an evaporator and a hydrodesulfurizer. 3. The hydrodesulfurizer is provided with a feedback system for returning the reformed gas from either the CO shifter outlet or the CO remover outlet of the fuel processing system. Fuel cell power generator. 4. The fuel cell power generator according to claim 1, wherein the hydrocarbon-based gas fuel supply system includes an adsorption desulfurizer. 5. The petroleum-based liquid fuel supply system is provided with a hydrodesulfurizer and an adsorptive desulfurizer connected in series with a hydrocarbon-based gas fuel supply system and connected in series downstream thereof. The fuel cell power generator according to claim 1. 6. The fuel cell power generator according to claim 1, wherein the reformer is a steam reformer. 7. The fuel cell power generator according to claim 1, wherein the reformer is an autothermal reformer. 8. The fuel cell power generator according to claim 1, wherein the reformer is a partial oxidation reformer. 9. During start-up operation, a hydrocarbon-based gas fuel from a hydrocarbon-based gas fuel supply system is supplied to a reformer of a fuel processing system, and a part of hydrogen obtained in the fuel processing system is hydrodesulfurized. When the hydrogen concentration in the inlet gas of the hydrodesulfurizer and the temperature of the desulfurizing agent packed bed are within the temperature range where the hydrogen gas is recycled and supplied to the inlet of the hydrodesulfurizer, the petroleum-based liquid fuel from the petroleum-based liquid fuel supply system is used. A method for operating a fuel cell power generator, comprising switching and desulfurizing a petroleum-based liquid fuel, reforming the petroleum-based liquid fuel into hydrogen, and operating the fuel cell main body to generate electricity with the reformed hydrogen.