JP2511883B2 - Fuel cell - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a fuel cell, and more particularly to an improvement in a fuel cell in which a reformer for producing fuel is incorporated inside the fuel cell. is there.

[Conventional technology]

BACKGROUND ART A fuel cell that electrochemically reacts a fuel with oxygen to extract electric energy is an effective power generation means with very little heat loss. However, in this type of fuel cell, large-scale equipment is required in addition to the cell body, and there is a dislike for a large-scale platen. That is, the reformer is one of them. The reformer is a device for reacting natural gas, alcohol or the like with steam to mainly convert into hydrogen and carbon dioxide in order to generate a fuel used in a fuel cell. This reformer is generally formed by arranging multiple layers of heat transfer particles or heat insulating tubes around a cylindrical reaction tube in terms of heat transfer characteristics. Therefore, it is easy to form a large-sized device and is usually arranged separately from the fuel cell main body.

However, recently, as disclosed in, for example, Japanese Patent Application Laid-Open No. 58-119167, it is known that the reformer is built in the fuel cell main body to reduce the installation floor area. .

Certainly, if this reformer is built in, the installation area becomes small, and the fuel cell equipment is also simplified, which is very effective.

[Problems to be solved by the invention]

However, since this reformer requires a predetermined amount of heat for its operation, it is generally formed so that this amount of heat can be given from the fuel cell main body. For this reason, both the heat quantity required for the reforming action and the heat quantity generated by the fuel cell in response to changes in load must be adjusted while operating both of them, which complicates the control device and operation, and is further incorporated. The piping to the reformer is complicated due to the relationship with other piping and parts, that is, the peripheral side surface of the fuel cell is interposed in the manifold, the piping connected to this manifold, and a predetermined part of the fuel cell main body. Since the cooling device pipes are scattered, the surroundings of the fuel cell body become complicated. Therefore, this type of fuel cell is disliked because of poor workability in assembling, disassembling, maintenance and inspection work.

The present invention has been conceived in view of this, and the purpose of the present invention is to incorporate a reformer of this kind that does not complicate the periphery of the fuel cell body and that allows easy temperature control of the fuel cell and the reformer. Providing a fuel cell.

[Means for solving problems]

That is, according to the present invention, the reformer is formed into a flat plate laminated type having a reforming catalyst packed layer and a fuel catalyst packed layer, and the flat plate laminated reformer is arranged at an end portion in the stacking direction of the fuel cell stack. It was done like this.

[Operation] When formed in this way, since the reformer is disposed at the end of the fuel cell body in the stacking direction, the gas supply / discharge pipes connected to the reformer are located on the peripheral side of the fuel cell body. It does not mix with the cooler pipes and manifolds that are led out from the parts, that is, the surroundings of the fuel cell body are cluttered, and it is easy to assemble, disassemble or inspect these various pipes. In addition, since the required amount of heat of the reformer is provided by the combustion catalyst packed bed built in the reformer, the temperature of the reformer can be adjusted without being influenced by the temperature of the fuel cell body. is there.

〔Example〕

The present invention will be described in detail based on the illustrated embodiments. 1 to 3 show a side surface and a plane of a fuel cell incorporating the reformer. In the figure, reference numeral 1 denotes a power generation section of a fuel cell, on which side faces manifolds 6a, 6b, 7a, 7b are arranged, and flat plate laminated reformer 3 is arranged at the upper and lower ends.

The power generation unit 1 and the flat plate reformer 3 are fastened at a predetermined pressure by the fastening metal fittings 4a, 4b and the fastening rods 5 arranged in the upper and lower parts in the figure, and are integrated with the fuel cell stack. There is.

A power collector and an insulating plate are interposed between the power generation unit 1 and the flat plate reformer 3, but they are shown as a block 2 here because they are not particularly related to the present invention. .

The manifolds arranged around the fuel cell stack are classified into the following four types depending on the location. That is, the fuel inlet manifold 6 for supplying fuel to the power generation unit 1
a, Fuel outlet manifold 6 for discharging spent fuel
b, an oxidant inlet manifold 7a for supplying the oxidant to the power generation unit 1, an oxidant outlet manifold 7b for discharging the spent oxidant (opposite side of the oxidant supply manifold 7a)
Is.

The flat plate laminated reformer 3 arranged at the upper and lower ends of the power generation unit is
A reforming catalyst packing layer 3a and a combustion catalyst packing layer 3b are provided, and a mixed gas introducing pipe 14, an exhaust pipe (opposite side of the mixed gas introducing pipe 14) 16, a raw fuel introducing pipe 10, and a reforming fuel introducing pipe, respectively. Combined with twelve.

Although not shown here, a cooler is interposed inside the power generation unit 1, and a pipe for supplying / discharging to / from the cooler is installed in the manifold.

In the fuel cell configured as described above, raw fuel gas such as natural gas to be reformed (hereinafter referred to as raw fuel 9) passes through the raw fuel introduction pipe 10 and the upper and lower flat plate reformers 3 are reformed. And is supplied to the high-quality catalyst packed bed 3a. Here, the fuel is reformed into a fuel suitable for the fuel cell (referred to as reformed fuel 11) and guided to the fuel inlet manifold 6a via the reformed fuel introduction pipe 12.
The reformed fuel 11 is supplied from the fuel inlet manifold to the fuel cell power generation unit 1, and reacts with the oxidant 18 introduced into the oxidant inlet manifold 7a through the oxidant inlet pipe 17 to generate DC power. The reaction surplus generated at the time of the reaction and the generated steam are the fuel outlet manifold 6b and the fuel exhaust pipe 13
And exhausted from the fuel cell through the oxidant outlet manifold 7b and the oxidant exhaust pipe 19 to form the fuel exhaust gas 21 and the oxidant exhaust gas 20, while being required for the reforming reaction in the flat plate reforming. Gas mixture of fuel and oxidizer to obtain heat
15 is supplied to the combustion catalyst packed bed 3b of the upper and lower flat plate reformer 3 via the mixed gas introduction pipe 14. A catalytic combustion reaction occurs in this portion, and heat is supplied to the reforming catalyst packed bed 3a. Of course, combustion exhaust gas (not shown) is discharged from the fuel cell through the exhaust pipe 16. The mixed gas 15 supplied to the flat plate reformer may be supplied from a separately prepared gas source, or the fuel exhaust gas 21 and the oxidation exhaust gas 20 from the fuel cell may be used. Which method should be used may be selected as an efficient method for the entire system.

In the fuel cell thus constructed, the flat plate reformer 3 having the reforming catalyst filling layer 3a and the combustion catalyst filling layer 3b is provided at the end of the fuel cell body 1 in the stacking direction. Since it is arranged integrally with the main body, the temperature of the reformer 3, that is, the amount of heat required for the reformer is adjusted without depending on the temperature of the fuel cell main body, that is, by the reaction of the combustion catalyst packed bed 3b. In addition, the raw fuel introduction pipe 10 and the reformed fuel introduction pipe 12 derived from the reformer 3 can be introduced to the side surface without any obstacles, and as in the conventional case, the cooler is provided on the side surface of the fuel cell body. It will not be mixed with water supply and drainage pipes and manifolds. Therefore, the assembling, disassembling, and inspecting work of these pipes becomes easy.

In the above description, the flat plate reformer 3 is provided at the upper and lower ends of the fuel cell stack, that is, at both ends of the fuel cell stack in the stacking direction. However, it is not always necessary to dispose at both ends. Of course, it may be arranged at either end depending on the required capacity of the reformer.

However, considering the overall heat balance of the fuel cell body, if possible, that is, even if one reformer is sufficient in capacity, it should be divided into two and placed at both ends of the fuel cell stack. Is desirable.

Further, as the configuration of the flat plate type reformer, the combustion catalyst packing layer is arranged in the middle of the reforming catalyst packing layer, but the reverse arrangement does not cause any problem.

〔The invention's effect〕

As described above variously, according to the fuel cell of the present invention, the reformer is formed into a flat plate laminated type having a reforming catalyst packed layer and a combustion catalyst packed layer, and the flat plate laminated type reformer is formed. Since the reactor is arranged at the end of the fuel cell stack in the stacking direction, the reformer can be installed without spending unnecessary nerves at the positions of the manifold and cooling pipes arranged on the peripheral side surface of the fuel cell stack. Assembling and disassembling operations can be easily performed, and the temperature control of the reformer can be easily and freely operated without being affected by the temperature of the fuel cell stack.

[Brief description of drawings]

FIG. 1 is a side view showing a fuel cell of the present invention, FIG. 2 is a plan view of the same, and FIG. 3 is a main part of a front view seen from the direction of the arrow Q in FIG. 1 ... Power generation unit, 3 ... Flat plate reformer, 3a ... Reforming catalyst packed bed, 3b ... Combustion catalyst packed bed, 6a ... Fuel inlet manifold, 6b ... Fuel outlet manifold, 7a ... … Oxidizer inlet manifold, 7b …… Oxidizer outlet manifold.

Claims (3)

(57) [Claims] 1. A fuel cell stack, a fuel inlet manifold for supplying fuel gas to the fuel cell stack, a fuel outlet manifold for discharging spent fuel gas, and a fuel cell on the peripheral side surface of the fuel cell stack. A reformer having an oxidant inlet manifold for supplying the oxidant gas to the stack and an oxidant outlet manifold for discharging the spent oxidant gas, and a reformer for supplying the reformed gas to the fuel inlet manifold are provided. The
A raw fuel introducing pipe for supplying the raw fuel gas of the reformed gas is connected to the reformer, an oxidant introducing pipe is connected to the oxidant inlet manifold, and the fuel outlet manifold and the oxidant outlet are connected. A fuel cell in which an exhaust pipe for exhausting each spent gas from each manifold is connected to the manifold, and the reformer is a flat plate stack in which a reforming catalyst packing layer and a combustion catalyst packing layer are adjacently arranged. And the raw fuel gas is communicated with the fuel inlet manifold through the reforming catalyst packed layer of the reformer, and the reformer is arranged at the stacking direction end of the fuel cell stack. And a mixture gas supply pipe to which a mixed gas of fuel and an oxidant is supplied and an exhaust pipe for discharging combustion exhaust gas of the mixed gas are connected to the combustion catalyst packed bed. Fuel cell. 2. The fuel cell according to claim 1, wherein the fuel cell stack is fastened in the stacking direction by a fastening tool, and between the fuel cell stack and the fastening fitting. A fuel cell in which the reformer is interposed. 3. The fuel cell according to claim 1, wherein the mixed gas supplied to the combustion catalyst packed bed of the reformer comprises the spent fuel gas and the spent oxidant gas. Characteristic fuel cell.