JPS6339620A - Reformer for fuel cell - Google Patents

Abstract

PURPOSE:To make it possible to preheat a fuel without using a preheater, by containing a distributing pipe in a casing, and opening a plurality of fuel- ejecting pipes branches from the distributing pipe into an evaporating pipe contained in the casing. CONSTITUTION:A fuel gas generated through evaporation at an evaporating part 1a of an evaporator 1 is fed into a reactor 8 after being heated while passing through an overheating part 1b, and is converted into a reformed gas consisting mainly of hydrogen in a catalyst layer 9. The reformed gas is fed into a collecting chamber 11, and is then fed to the main body of a fuel cell. On the other hand, a heating gas generated at a burner 2 serves to evaporate and overheat a fuel at the evaporator 1, then flows through a central passage 20 into a heating space 7, heats the reactor 8 while flowing upward through the space 7, and sequentially flows through multi-stage through-holes 16 into a heating passage 14. The heating gas flows upward through the heating passage 14, turns back at a communicating port 17 provided at the upper end of the passage 14, then flows downward through an exhaust passage 15, and is exhausted through an exhaust port 18 to the exterior.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fuel reformer in a fuel cell.

[Prior art]

A fuel cell mainly consists of a reformer that converts fuel into hydrogen, and a fuel cell main body that reacts the hydrogen generated in the reformer with air (oxygen) and converts it into water and electricity.

The reformer vaporizes fuel (for example, a mixture of methanol and water) using an evaporator, passes the vaporized fuel gas through a catalyst layer in a reaction tube, and converts it into a reformed gas consisting mainly of hydrogen gas.
It is designed to send it to the fuel cell itself.

Generally, a preheater is connected to the fuel supply path to the evaporator of the reformer to increase evaporation efficiency.
Fuel preheated by this preheater is supplied to the evaporator. However, this preheater increases the size of the fuel supply section and increases the number of parts during assembly.

[Purpose of the invention]

An object of the present invention is to provide a fuel cell reforming device that enables preheating of fuel while omitting the preheater specially provided in the conventional device described above, and which enables a reduction in the number of parts and a compact device. It's about doing.

[Structure of the invention]

A fuel cell reformer of the present invention that achieves the above object is a reformer in which a plurality of fuel discharge pipes branched from a distribution pipe are opened to an evaporator housed in a case. It is characterized by being housed in a case.

〔Example〕

In the embodiment shown in the figure, 1 is an evaporator for vaporizing fuel, a burner 2 is arranged below it as a heater, and a fan 26 forces combustion air into a case surrounding the outside of the burner 2. It is designed to be ventilated. The evaporator 1 is formed into an annular shape, and its interior is divided into two parts: an evaporating section 1a for vaporizing fuel liquid and a superheating section 1b for superheating the vaporized fuel gas.

An annular distribution pipe 4 is arranged on the outer periphery of the upper surface of the evaporator 1 so as to be in contact with or close to it.

A fuel supply pipe 3 is connected to this distribution pipe 4 from the outside, and a plurality of fuel discharge pipes 5.・－・、5
is branched at predetermined intervals along the circumference, and each end is penetrated into the evaporator section la to discharge a mixed fuel of methanol and water.

The evaporator 1 is housed in a case 6 serving as an outer shell, a heating space 7 is formed above the case 6, and a partition wall 1 is further formed above the case 6.
A collecting chamber 11 is provided through the reactor 0 to collect the reformed gas after the reaction. A ring-shaped reactor 8 is installed in the heating space 7, and a catalyst layer 9 is filled inside the reactor.

This reactor 8 has a lower end in communication with the evaporator 1 via a connection 12 and an upper end in direct communication with the collecting chamber 11 .

The reactor 8 has a large number of through holes 16 extending from the inner circumferential side to the outer circumferential side. -., 16 are provided in multiple stages in the vertical direction and are arranged in parallel in the circumferential direction. The through holes 16 at each stage are
As shown in the figure, they may overlap in plan view (or they may be offset). A partition wall 13 is located between the outer circumferential wall of the reactor 8 and the case 6 in which such a through hole 16 is present. It is divided into two parts, an inner and an outer part, and forms an annular heating passage 14 and an annular exhaust passage 15, respectively.

17 and communicate with each other. Further, an exhaust port 18 is provided in the lower part of the case 6, and the exhaust passage 15 is communicated with the outside.

In the above configuration, the fuel gas vaporized in the evaporation section 1b of the evaporator 1 is superheated when passing through the superheating section 1b, enters the reactor 8, and changes into a reformed gas mainly consisting of hydrogen in the catalyst layer 9. The fuel enters the upper gathering chamber 11 and is then sent to the fuel cell main body (not shown). On the other hand, the heated gas generated in the burner 2 vaporizes the fuel in the evaporator 1 and superheats it, then enters the center of the heating space 7 from the central passage 20 and heats the reactor 8 while rising there. while sequentially passing through the multistage through holes 16 into the heating passage 14,
It ascends there, turns around the communication port 17 at the upper end, then descends through the exhaust passage 15 and is exhausted to the outside through the exhaust port 18.

According to the fuel reformer described above, since the fuel distribution pipe 4 is provided inside the case 6, the fuel supplied to the distribution pipe 4 is heated by the heated gas flowing down the exhaust passage 15, and the fuel is heated by the heated gas flowing down the exhaust passage 15. By contacting or being close to the outer wall of the evaporator 1, heat is also generated from the evaporator 1. That is, the fuel supplied from the fuel supply pipe 3 to the distribution pipe 4 is preheated here, and after preheating, it is distributed to a plurality of fuel discharge pipes 5 and discharged to the evaporation section 1a.

Therefore, in the above-mentioned reformer, the distribution pipe 4 itself acts as a preheater, making it unnecessary to provide a special preheater as in the prior art. Therefore, the number of parts can be reduced and the device can be made more compact.

〔Effect of the invention〕

As mentioned above, in the fuel cell reformer of the present invention, the distribution pipe for the fuel discharge pipe is housed in the case that houses the evaporator, so this distribution pipe itself acts as a preheater, and is different from the conventional one. This eliminates the need for a special preheater. Therefore, the number of parts can be reduced and the device can be made more compact.

[Brief explanation of the drawing]

FIG. 1 shows a fuel cell reformer according to an embodiment of the present invention, and FIG. 2 is a view taken along arrow nu in FIG. DESCRIPTION OF SYMBOLS 1... Evaporator, 2... Burner, 4... Distributor, 5... Fuel discharge pipe, 6... Case, 8...
・Reactor.

Claims (2)

[Claims] (1) In a reformer in which a plurality of fuel discharge pipes branched from a distribution pipe are opened to an evaporator housed in a case,
A reformer for a fuel cell, characterized in that the distribution pipe is housed in the case. (2) The fuel cell reformer according to claim 1, wherein the distribution pipe is in contact with or close to the outer wall of the evaporator.