JP2000063101A - Fuel reforming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact fuel reforming apparatus in which smooth starting is performed and has good heat efficiency. SOLUTION: This reformer 26 is equipped with first and second reforming catalyst layers 38 and 40 arranged in a reforming chamber 36 and a feeding mechanism 42 for simultaneously carrying out oxidation reaction and reforming reaction in the first and second reforming catalyst layers 38 and 40 by feeding steam and oxygen thereto. In these first and second reforming catalyst layers 38 and 40, the face direction is set in doughnut form which is perpendicular to flow direction of the reforming chamber 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel reformer for reforming a reforming fuel containing hydrocarbon to produce reformed gas containing hydrogen.

[0002]

2. Description of the Related Art For example, a fuel cell stack has been developed which is constructed by stacking a plurality of fuel battery cells in which an anode-side electrode and a cathode-side electrode are opposed to each other with a solid polymer electrolyte membrane sandwiched between them and a separator. And is being put to practical use for various purposes.

A fuel cell stack of this type is composed of hydrocarbons,
For example, by supplying a reformed gas (fuel gas) containing hydrogen generated by steam reforming of an aqueous methanol solution to the anode electrode and supplying an oxidant gas (air) to the cathode electrode, the hydrogen gas Are ionized and flow in the solid polymer electrolyte membrane, whereby electric energy is obtained outside the fuel cell.

As described above, the steam reforming reaction for reforming an aqueous methanol solution to produce a reformed gas containing hydrogen is carried out by C
It is an endothermic reaction represented by H ₃ OH + H ₂ O → CO ₂ + 3H ₂ . Therefore, in order to supply the amount of heat required for the reforming reaction, a complicated heat transfer structure is usually incorporated in the reformer, which complicates the structure.

Therefore, for example, Japanese Patent Laid-Open No. 9-315801
As disclosed in Japanese Patent Application Laid-Open No. 7-315801 and Japanese Patent Application Laid-Open No. 7-315801, oxygen is supplied to a raw fuel gas containing hydrocarbon to cause an oxidation reaction which is an exothermic reaction, and the amount of heat released by this oxidation reaction. There is known a method in which the reforming reaction of the raw fuel gas, which is an endothermic reaction, is carried out by utilizing. This allows
The advantage is that the structure can be simplified.

[0006]

By the way, since the oxidation reaction rate is generally higher than the reforming reaction rate, the temperature on the inlet side of the reforming catalyst rises while the reforming catalyst, which is important in the reforming reaction, increases. The temperature on the outlet side of the is likely to drop. However,
In the above-mentioned conventional technique, since the reforming catalyst (pellets) is configured to be long in the gas flow direction, the temperature difference in the gas flow direction of the reforming catalyst becomes large, and the desired reforming is performed over the entire catalyst layer. It has been pointed out that the quality reaction cannot be realized. Moreover, pellets are inferior in compactness, and it is extremely difficult to equalize the temperatures of the reforming catalyst.

Further, as the reforming catalyst, a structure in which plate type reforming catalyst layers and catalytic combustion chambers are alternately laminated is usually employed (see, for example, Japanese Patent Application Laid-Open No. 8-253301). However, this type of reforming catalyst layer is generally set in a rectangular plate shape, and the entire case forming the reformer has a rectangular shape. Therefore, there is a problem that stress concentration is likely to be caused in the case, and the case becomes thick, so that the reformer cannot be downsized as a whole.

On the other hand, when starting the steam reforming of the aqueous methanol solution, it is necessary to raise the temperature of the reforming catalyst to a predetermined temperature. Therefore, heat such as steam is usually supplied to the reformer from a device arranged outside the reformer. However, in a fuel cell stack used for vehicles, a highly efficient and compact reformer is required, and the above structure cannot be adopted.

The present invention solves this kind of problem, and provides a fuel reformer capable of smoothly performing a desired reforming reaction with a simple structure and easily reducing the size of the entire device. The purpose is to provide.

It is another object of the present invention to provide a compact fuel reformer which has a smooth start-up, a high thermal efficiency and a compact size.

[0011]

The fuel reforming apparatus according to the present invention
In the installation, the reforming fuel is placed in the reforming chamber where the reforming catalyst layer is arranged,
Water vapor and oxygen are supplied, so-called autotherma
In this reforming catalyst layer, oxidation reaction and fuel reforming reaction
Response is performed at the same time. Specifically, CH₃OH + 3 /
2O₂→ CO₂+ 2H₂O (exothermic reaction) and CH₃OH
+ H₂O → CO ₂+ 3H₂(Endothermic reaction) and simultaneous
This eliminates the need for a complicated heat transfer structure inside the reformer,
The body structure is simplified.

Further, since the reforming catalyst layer has a donut shape whose surface direction is orthogonal to the gas flow direction in the reforming chamber, the reforming catalyst layer can be made thin, and the reforming catalyst layer can be made thin. The temperature at the outlet side of the layer can be secured at the temperature required for the reforming reaction. Moreover, it becomes possible to equalize the temperature of the entire reforming catalyst layer and reduce the pressure loss of the reforming catalyst layer. In addition, since the reforming catalyst layer is doughnut-shaped, the reformer itself is formed into a cylindrical shape, which prevents stress concentration from occurring and allows the case to be made thinner. This allows
A reformed gas containing hydrogen can be efficiently generated with a simple and compact structure.

Further, a plurality of reforming catalyst layers are arranged in parallel in the gas flow direction, and a gas flow path between the reforming catalyst layers passes through the reforming catalyst layer and bypasses the other reforming catalyst layers. Forming means are arranged. Therefore, the entire reformer can be effectively downsized, and the gas can be uniformly supplied to each reforming catalyst layer.

Furthermore, since the flow path member is provided which forms a conical gas supply flow path whose diameter increases toward the reforming catalyst layer, the gas is uniformly supplied in the radial direction of the reforming catalyst layer. be able to. Moreover, by allowing the gas to flow along the outer peripheral portion of the reforming catalyst layer, it is possible to prevent the heat radiation from the outer peripheral portion of the reforming catalyst layer, so that the temperature distribution in the radial direction of the reforming catalyst layer is uniform. Be converted.

Further, a conical cover member is attached to the central hollow portion of the reforming catalyst layer arranged on the most downstream side in the gas flow direction. Therefore, the gas can be smoothly and reliably supplied to the entire surface of the most downstream reforming catalyst layer.

Further, in the present invention, the starting combustion mechanism is arranged on the upstream side of the reforming catalyst layer, and the combustion gas for heating is directly supplied to the reforming catalyst layer at the time of starting. Thereby, the warm-up time of the reforming catalyst layer can be shortened all at once, and the reformed gas can be efficiently obtained. Moreover, the water generated by the starting combustion mechanism can be used for the reforming reaction, and the water supply structure can be simplified.

Furthermore, the surface direction of the donut-shaped reforming catalyst layer is set to a shape orthogonal to the gas flow direction in the reforming chamber. Therefore, the thickness of the reforming catalyst layer can be reduced, and the temperature distribution of the reforming catalyst layer can be equalized. Further, the case itself in which the reforming catalyst layer is arranged can also be set in a cylindrical shape, and it becomes possible to avoid stress concentration and to considerably thin the case itself.

Further, since the reforming catalyst layer and the starting combustion mechanism are concentrically arranged, the gas can flow from the center to the outside of the reforming catalyst layer, and the reforming catalyst layers are multi-staged. It is possible to stack them. Moreover, the doughnut-shaped reforming catalyst layer can be uniformly warmed as a whole by the combustion gas.

Further, the starting combustion mechanism is provided with an injector for supplying fuel. Therefore, the fuel supply amount can be set accurately, and in particular, ignition, flame holding, and temperature control can be easily performed. Moreover, the fuel can be supplied with good responsiveness by increasing the reforming raw material hydrocarbon from the injector for start-up in response to a sudden increase in load, such as an increase in the amount of produced hydrogen gas.

Further, an air nozzle for deriving air from the periphery of the injector is arranged. Therefore, by supplying air during steady operation, it is possible to effectively prevent the generation of deposits on the injector. Moreover, due to the cooling action of the air injected from the air nozzle, there is no need to use an expensive and highly heat-resistant injector, and an inexpensive injector can be used, which is extremely economical. Furthermore, by giving a swirling flow to the air, it becomes possible to mix the fuel and air evenly,
Reaction unevenness in the reforming catalyst layer is reliably avoided.

Furthermore, the supply mechanism is provided with a supply port for the reforming fuel, steam and oxygen-containing air which is arranged downstream of the injector and upstream of the reforming catalyst layer. Therefore, the temperature of the combustion gas can be effectively controlled by mixing air with the reforming fuel and steam at the time of starting.

[0022]

1 is a schematic configuration diagram of a fuel cell system 12 incorporating a fuel reforming apparatus 10 according to an embodiment of the present invention. The fuel cell system 12 includes a fuel reforming apparatus 10 according to the present embodiment that produces hydrogen gas by reforming a reforming fuel containing hydrocarbons, and reforming gas is supplied from the fuel reforming apparatus 10. In addition, air is supplied as an oxidant gas, and the fuel cell stack 14 is configured to generate electricity by hydrogen gas in the reformed gas and oxygen in the air. As the hydrocarbon, methanol, natural gas, methane or the like can be used.

The fuel reformer 10 may be a hydrocarbon, such as
A methanol tank 16 for storing methanol, a water tank 18 for storing produced water or the like discharged from the fuel cell system 12, a predetermined amount of methanol and water are supplied from the methanol tank 16 and the water tank 18, respectively, and methanol is supplied. A mixer 20 for mixing the aqueous solutions, an evaporator 22 for evaporating the aqueous methanol solution supplied from the mixer 20, a catalytic combustor 24 for supplying heat of evaporation to the evaporator 22, and an evaporator 22. A reformer 26 that reforms an introduced vaporized methanol aqueous solution (hereinafter referred to as reforming fuel) to generate a reformed gas containing hydrogen gas, and a reformed gas derived from the reformer 26. CO remover 28 for removing carbon monoxide therein.

The catalytic combustor 24 and the CO remover 28 include
Air is supplied from the air supplier 30, and a heat exchanger 32 for lowering the temperature of the reformed gas is arranged between the reformer 26 and the CO remover 28. Evaporator 22, reformer 26, heat exchanger 32, CO
The remover 28 and the catalytic combustor 24 are connected via a pipe 34 to form a circulation flow path (see FIG. 2).

As shown in FIG. 3, the reformer 26 includes first and second reforming catalyst layers 38 and 40 arranged in a reforming chamber 36.
In order to supply an aqueous methanol solution, steam and an oxygen-containing gas such as air to the reforming chamber 36 to cause the first and second reforming catalyst layers 38 and 40 to simultaneously perform the oxidation reaction and the reforming reaction. Is provided upstream of the supply mechanism 42 and the first and second reforming catalyst layers 38, 40, and directly supplies the combustion gas for heating to the first and second reforming catalyst layers 38, 40 at the time of starting. And a combustion mechanism 44 for starting.

As shown in FIGS. 2 and 3, the combustion mechanism 4
Reference numeral 4 corresponds to the upstream side of the reformer 26 in the gas flow direction (direction of arrow A) and the first and second reforming catalyst layers 38, 40.
The combustion mechanism 44 is provided concentrically with the above, and the combustion mechanism 44 includes an injector 48 for supplying fuel, for example, methanol to the combustion chamber 46, and a glow plug 49 as an ignition plug.
With. The injector 48 is connected to the methanol tank 16 via a fuel path 50 (see FIG. 1).

Around the tip end side of the injector 48, as shown in FIG.
As shown in FIG. 5, an air nozzle 52 is mounted, and the air nozzle 52 is provided with four air outlets 54a to 54d that open toward the combustion chamber 46. As shown in FIG. 4, the respective air outlets 54a to 54d are set with respective injection directions and angles so as to generate a vortex in the combustion chamber 46. The air nozzle 52 has a first air path 56.
Is connected to the air supply device 58 or the air supply device 30 (see FIG. 1).

As shown in FIGS. 2 and 3, the supply mechanism 42 is arranged on the downstream side of the combustion mechanism 44 and is located downstream of the injector 48 and upstream of the first reforming catalyst layer 38. A supply port 60 is provided through which the quality fuel and the fuel gas, which is steam, and the oxidizing and diluting air are mixed or independently supplied. The supply port 60 is connected to the evaporator 22 through a path 34a, and also the path 34a.
The joint portion 62 provided on the way to the above is in communication with the air supplier 30 via the second air path 64, for example.
The supply port 60 communicates with the dilution chamber 66 from the plurality of introduction ports 60b through the opening 60a in the double wall.

The reformer 26 has a diffuser portion (flow passage member) which forms a conical gas supply flow passage 68 whose diameter increases from the dilution chamber 66 communicating with the combustion chamber 46 toward the first reforming catalyst layer 38. 70 is provided. A substantially cylindrical case 72 is screwed to the end of the diffuser portion 70 where the diameter increases,
In the case 72, the first and second reforming catalyst layers 38, 4 are provided.
0 is installed.

The first and second reforming catalyst layers 38, 40 are
It is composed of a copper or zinc-based catalyst and has a donut-shaped honeycomb structure. The plane direction of each honeycomb catalyst is the flow direction of the gas in the reforming chamber 36 (arrow A
Direction) and are parallel to each other. First and second straightening vanes 74a, 74b are fixed to the upstream sides of the first and second reforming catalyst layers 38, 40 in the gas flow direction. The first and second straightening vanes 74a, 74b have an appropriate pressure loss, equalize the flow of gas to the first and second reforming catalyst layers 38, 40, and in each catalyst layer plane. Equalize the flow.

Between the first and second reforming catalyst layers 38 and 40, a gas flow path forming means 76 is arranged so that the reforming fuel gas passes through only one of them. The gas flow path forming means 76 is made of, for example, a SUS plate material, and has a tubular portion 78 inserted into the central cavity portion 38a of the first reforming catalyst layer 38, and an end portion of the tubular portion 78. And a conical portion 80 that increases in diameter in the direction of gas flow from the
And a ring portion 82 that is integrally provided at the end of the second reforming catalyst layer 40 and covers the outer periphery of the second reforming catalyst layer 40. The tip of the tubular portion 78 is
A throttle-shaped portion 84 whose diameter is reduced in the direction opposite to the gas flow direction is integrally formed. By appropriately selecting the shape of the narrowed portion 84, the distribution state of the gas flowing into the first and second reforming catalyst layers 38, 40 can be adjusted. A conical cover member 86 is attached to the central hollow portion 40a of the second reforming catalyst layer 40.

As shown in FIG. 2, a three-way valve 90 is provided at the joint portion 88 of the paths 34b and 34c which constitute the pipe 34 and are connected to the catalytic combustor 24 and the CO remover 28, respectively.
Is provided, and the three-way valve 90 is
And a position where the fuel cell stack 14 communicates with the path 3
It is possible to switch to a position where 4b and the path 34c communicate with each other. An introduction port 92 for introducing a gas such as unreacted hydrogen gas in the exhaust component discharged from the fuel cell stack 14 is arranged in the path 34c.

The operation of the fuel reforming apparatus 10 thus constructed will be described below.

First, when the fuel reforming apparatus 10 is started, the paths 34b and 34c of the pipe 34 are in a disconnected state from the fuel cell stack 14 in the starting warm-up mode. Therefore, from the first air path 56 that constitutes the combustion mechanism 44 to the air nozzle 52
Air is supplied to the combustion chamber 46 via the
A vortex is formed inside. In this state, the glow plug 49
Is driven and the temperature of the glow plug 49 reaches a predetermined temperature, the methanol tank 16 is moved to the injector 4
Methanol is supplied to 8.

Methanol is sprayed into the combustion chamber 46 through the injector 48, and the vortex flow of air acts on the methanol to atomize and diffuse the methanol. Therefore, in the combustion chamber 46,
Methanol burns under the heating action of the glow plug 49,
Flame holding is performed only in the combustion chamber 46.

Next, the diluting air is introduced into the diluting chamber 66 from the second air passage 64 through the plural inlets 60b. Therefore, the high temperature combustion gas generated in the combustion chamber 46 is mixed with air, and the fuel gas is arranged in the reforming chamber 36 in a state where the temperature of the combustion gas is adjusted. It is directly supplied to the quality catalyst layers 38 and 40. Furthermore, after the first and second reforming catalyst layers 38, 40 are heated to a predetermined temperature, an aqueous methanol solution in which methanol and water are mixed at a predetermined mixing ratio is supplied to the evaporator 22 through the mixer 20. To be done.

In the evaporator 22, the high temperature combustion gas generated in the catalytic combustor 24 and the evaporative gas exchange heat with each other to vaporize the aqueous methanol solution, which is mixed with the air sent from the second air passage 64 to supply it. While being supplied into the reformer 26 from the plurality of inlets 60b forming the fuel cell 42, the supply of methanol from the injector 48 into the combustion chamber 46 is stopped. Here, air is continuously supplied from the first air path 56 to the combustion chamber 46 side via the air nozzle 52, effectively lowering the temperature of the injector 48 itself.

In this case, in this embodiment, the combustion mechanism 44 is directly connected to the reformer 26, and the combustion gas generated in the direct combustion chamber 46 using hydrocarbon such as methanol as fuel is directly First and second reforming catalyst layers 3 in reforming chamber 36
It supplies to 8, 40. Therefore, at the time of starting, the reformer 26 and the like can be heated to a desired temperature in a short time, and the time required for starting can be shortened all at once.

Further, since the combustion gas is diluted with the air introduced into the diluting chamber 66, the combustion gas is introduced into the reforming chamber 36 in a temperature controlled state, and the partial oxidation and unoxidized at a constant temperature occur. Reforming of combustion hydrocarbons is performed. This partial oxidation reaction makes it possible to further raise the temperature in the reformer 26, and the reforming reaction is performed from the time of starting via the unburned hydrocarbons and the water produced by the combustion, so that hydrogen gas is generated. Be evoked. This hydrogen gas is sent to the catalytic combustor 24 and can be used as fuel, and is used to raise the temperature of the catalytic combustor 24 and the evaporator 22.

Moreover, even when the load is suddenly increased, for example, the amount of produced hydrogen gas is increased, by spraying methanol from the injector 48, the methanol can be instantly evaporated and vaporized to effectively compensate for the lack of heat. it can. Further, the combustion mechanism 44 includes the first and second reforming catalyst layers 38, 4
It is installed concentrically with 0, and the first
And, it becomes possible to uniformly heat the second reforming catalyst layers 38 and 40 as a whole.

Furthermore, in the present embodiment, an air nozzle 52 is provided for drawing air from the periphery of the injector 48 into the combustion chamber 46. Due to the vortex flow of the air injected from the air nozzle 52, the atomization and diffusion of the methanol sprayed from the injector 48 is achieved, and the combustion is completed in a narrow range in the combustion chamber 46.
The flame holding range can be limited. Therefore, there is an advantage that it is possible to reliably control the combustion gas to a desired temperature by the dilution air introduced from the second air passage 64 while maintaining the certainty and flame holding property of the flame.

Further, by injecting air from the air nozzle 52 during steady operation, it is possible to prevent the injector 48 from being heated and to reliably prevent a deposit from being generated in the injector 48. become. Further, due to the cooling effect of the air jetted from the air nozzle 52, the injector 48 does not need to have high heat resistance, and an inexpensive injector 48 can be used, which is extremely economical.

By the way, the reforming fuel gas supplied from the evaporator 22 to the passage 34a is mixed with the air injected from the second air passage 64 and introduced into the reformer 26, and then the diffuser portion 70 is formed. Sent to the side. This diffuser part 7
At 0, part of the reforming fuel gas containing the aqueous methanol solution, water vapor and oxygen is sent to the first reforming catalyst layer 38 along the gas supply flow path 68, while the other part is fed to the first reforming catalyst layer 38.
The reforming catalyst layer 38 is sent to the second reforming catalyst layer 40 through the inside of the tubular portion 78 fitted in the central hollow portion 38a.

In the first and second reforming catalyst layers 38 and 40, an oxidation reaction, which is an exothermic reaction, and a fuel reforming reaction, which is an endothermic reaction, are simultaneously performed by methanol vapor and oxygen in the reforming fuel gas. As a result, it is not necessary to use a complicated heat transfer structure in the reformer 26,
The entire structure can be simplified at once. Moreover,
Since the heat required for the reforming reaction is supplied by the exothermic reaction in the reformer 26, the responsiveness to the load fluctuation is good, and the reformed gas containing hydrogen gas can be efficiently generated.

The reformed gas generated through the first reforming catalyst layer 38 and the reformed gas generated through the second reforming catalyst layer 40 are introduced into the heat exchanger 32 to reach a predetermined temperature. To be cooled. Next, the reformed gas is introduced into the CO remover 28 to selectively react and remove CO in the reformed gas, and then sent to the catalytic combustor 24 as required. And
When stable reformed gas is generated from the reformer 26,
The reformed gas is supplied to the fuel cell stack 14 by switching the three-way valve 90.

In this case, in this embodiment, since the first and second reforming catalyst layers 38, 40 are set in a donut shape, the case 72 constituting the reformer 26 can be set in a cylindrical shape. The occurrence of stress concentration is prevented and the case 72 can be made thinner. Further, since the first and second reforming catalyst layers 38, 40 have a donut shape, the central portion thereof is used as a passage, and the gas is caused to flow from the center toward the outer periphery, whereby the first and second reforming catalyst layers are formed. Layer 38,
It is possible to stack 40 in multiple stages.

Furthermore, the first and second reforming catalyst layers 3
The catalyst outlet temperature, which is important in the reforming reaction, can be kept high by setting the thicknesses of 8 and 40 to be thin. That is, as shown in FIG. 5, an experiment was conducted in which a raw material gas (fuel gas) was introduced into the reforming catalyst layer M to generate a reformed gas. Here, when the thickness h of the reforming catalyst layer M was changed, the results shown in FIG. 6 were obtained. The maximum temperature of the reforming catalyst layer M is 3
The temperature was controlled to 25 ° C., and the thinner the thickness h of the reforming catalyst layer M, the higher the methanol reaction rate and the result that the performance was improved.

As a result, the first and second reforming catalyst layers 3
By making the thicknesses 8 and 40 thin, the reformed gas is efficiently generated and the first and second reforming catalyst layers 3 are formed.
It is possible to obtain the effect that the temperatures of 8 and 40 as a whole are equalized and the pressure loss is reduced.

Furthermore, in the present embodiment, the first and second reforming catalyst layers 38 and 40 are arranged in parallel with respect to the gas flow direction, and the first and second reforming catalyst layers 38 and 40 are respectively arranged via the gas flow path forming means 76. It is divided into two gas passages that pass only the two reforming catalyst layers 38 and 40. Therefore, it is possible to arrange the first and second reforming catalyst layers 38, 40 or more catalyst layers in a small volume in the reformer 26, and to effectively downsize the reformer 26. Will be possible. Moreover,
The gas can be evenly supplied to the first and second reforming catalyst layers 38 and 40, and the reformed gas can be efficiently generated.

Further, in the reformer 26, a diffuser portion 70 is provided on the way from the combustion chamber 46 to the reforming chamber 36 to form a conical gas supply passage 68 whose diameter increases in the gas flow direction. ing. Therefore, the first reforming catalyst layer 3
The reforming supply gas can be uniformly supplied in the radial direction of 8, and the reforming reaction can be efficiently performed. further,
The reformed gas, which has been reformed through the first reforming catalyst layer 38, moves to the second along the conical portion 80 that constitutes the gas flow path forming means 76.
It is supplied to the outer peripheral portion of the reforming catalyst layer 40. Therefore, the second
It is possible to prevent heat radiation from the outer peripheral portion of the reforming catalyst layer 40, and it is possible to maintain a uniform temperature distribution in the radial direction of the second reforming catalyst layer 40.

Furthermore, a conical cover member 86 is attached to the central hollow portion 40a of the second reforming catalyst layer 40. Thereby, the central cavity portion 3 of the first reforming catalyst layer 38
The reforming fuel gas that has reached the cover member 86 through 8a is smoothly supplied in the radial direction of the second reforming catalyst layer 40 along the inclination of the cover member 86, and an efficient reforming reaction is performed. It will be possible. In addition, the first and second reforming catalyst layers 38,
40 constitutes a honeycomb-supported catalyst layer, and can effectively increase the catalyst surface area.

In this embodiment, the reforming chamber 36 has a first
The second reforming catalyst layers 38 and 40 are arranged in two stages, but the present invention is not limited to this, and the same effect can be obtained even if three or more stages of reforming catalyst layers are provided. You can

[0053]

EFFECTS OF THE INVENTION In the fuel reforming apparatus according to the present invention, an oxidation reaction and a reforming reaction are simultaneously performed in the reforming catalyst layer, and the reforming catalyst layer is orthogonal to the gas flow direction in the reforming chamber. It is set in a donut shape. For this reason, the structure of the entire device is effectively simplified, the occurrence of stress concentration is prevented, and the device can be easily reduced in thickness. This makes it possible to efficiently generate a reformed gas containing hydrogen with a simple and compact structure.

Further, in the fuel reforming apparatus according to the present invention, the starting combustion mechanism is arranged on the upstream side of the reforming catalyst layer,
By directly supplying the combustion gas for heating to the reforming catalyst layer at the time of starting, the warm-up time can be shortened all at once and the reformed gas can be efficiently obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory diagram of a fuel cell system incorporating a fuel reformer according to an embodiment of the present invention.

FIG. 2 is a perspective explanatory view of the fuel reformer.

FIG. 3 is a vertical cross-sectional explanatory view of a reformer that constitutes the fuel reformer.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is an explanatory diagram of an experiment for detecting a change in the methanol reaction rate due to a difference in the thickness of the reforming catalyst layer.

FIG. 6 is a diagram for explaining the results of the methanol reaction rate obtained by the above experiment.

[Explanation of symbols]

10 ... Fuel reformer 12 ... Fuel cell system 14 ... Fuel cell stack 16 ... Methanol tank 18 ... Water tank 20 ... Mixer 22 ... Evaporator 24 ... Catalytic combustor 26 ... Reformer 28 ... CO remover 38, 40 Reforming catalyst layer 42 Supply mechanism 44 Combustion mechanism 46 Combustion chamber 48 Injector 50 Fuel path 52 Air nozzles 54a to 54d Air outlets 56, 64 Air path 60 Supply port 60a Open 60b Introducing port 66 ... Diluting chamber 68 ... Gas supply flow path 70 ... Diffuser part 72 ... Case 76 ... Gas flow path forming means 78 ... Cylindrical part 80 ... Cone part 82 ... Ring part 86 ... Cover member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hikaru Okada             1-4-1 Chuo, Wako City, Saitama Book             T-Tech Research Institute (72) Inventor Shoji Isobe             1-4-1 Chuo, Wako City, Saitama Book             T-Tech Research Institute F-term (reference) 4G040 EA03 EA06 EB04 EB12 EB24                 5H027 AA06 BA01 BA09 BA10 BA16

Claims (10)

[Claims] 1. A fuel reforming apparatus for producing a reformed gas containing hydrogen by reforming a reforming fuel containing hydrocarbon, comprising: a reforming catalyst layer arranged in a reforming chamber; A supply mechanism for supplying the reforming fuel, steam and oxygen to the reforming chamber to cause the reforming catalyst layer to simultaneously perform an oxidation reaction and a reforming reaction, the reforming catalyst layer comprising: The fuel reformer is characterized in that the plane direction is set in a donut shape orthogonal to the gas flow direction in the reforming chamber. 2. The fuel reformer according to claim 1, wherein a plurality of the reforming catalyst layers are arranged in parallel in the gas flow direction, and one reforming catalyst layer is provided between the reforming catalyst layers. A fuel reforming device, characterized in that a gas flow path forming means is disposed so as to pass through the above and other bypassing the reforming catalyst layer. 3. The fuel reforming apparatus according to claim 1 or 2, further comprising: a flow path member that forms a conical gas supply flow path whose diameter increases toward the reforming catalyst layer. Reformer. 4. The fuel reforming apparatus according to claim 1, wherein a central hollow portion of the reforming catalyst layer arranged at the most downstream in the gas flow direction has a conical shape. A fuel reformer comprising a cover member attached. 5. A fuel reforming apparatus for producing a reformed gas containing hydrogen by reforming a reforming fuel containing hydrocarbon, comprising a reforming catalyst layer arranged in a reforming chamber, A supply mechanism for supplying the reforming fuel, steam, and oxygen to the reforming chamber to cause an oxidation reaction and a reforming reaction in the reforming catalyst layer at the same time, and an upstream side of the reforming catalyst layer. And a starting combustion mechanism for performing combustion in a combustion chamber communicating with the reforming chamber and directly supplying a combustion gas for heating to the reforming catalyst layer at the time of starting. Reformer. 6. The fuel reforming apparatus according to claim 5, wherein the reforming catalyst layer has a donut shape whose surface direction is orthogonal to a gas flow direction in the reforming chamber. Reformer. 7. The fuel reformer according to claim 6, wherein the reforming catalyst layer and the starting combustion mechanism are concentrically arranged. 8. The fuel reformer according to claim 5, wherein the starting combustion mechanism includes an injector for supplying fuel to the combustion chamber. 9. The fuel reformer according to claim 8, wherein the starting combustion mechanism includes an air nozzle for drawing out air from around the injector. 10. The fuel reformer according to claim 9,
The supply mechanism is provided with a supply port for the air containing the reforming fuel, the steam and the oxygen, which is arranged downstream of the injector and upstream of the reforming catalyst layer. .