JPS63298975A - Temperature rising device for air cooled fuel cell - Google Patents

Abstract

PURPOSE:To efficiently raise the temperature of a cell with a simple device by installing an air supply means which cools combustion gas to an optimum temperature by normal temperature air sucked from the outside in a supply pipeline of combustion gas for a starting burner. CONSTITUTION:When an air cooled fuel cell 10 is started, a valve 26 is opened, and a blower 9 is operated to suck the air in a starting burner 21, then fuel is supplied to generate combustion gas. The combustion gas is circulated in a supply pipeline 15 with the blower 9 and the temperature of a cell 10 is raised. During this operation, the opening of an air supply valve 27 is adjusted to control the amount of air, and high temperature combustion gas is cooled to a certen temperature which is optimum to raise the temperature of the cell 10. When the temperature of the cell is raised to a specified value, the operation of the burner 21 is stopped and the air supply valve 27 is closed to keep the temperature of the cell constant. The temperature of the cell is efficiently raised with a simple device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a temperature raising device for an air-cooled fuel cell, which supplies a cooling gas independent of a reactant gas to a cooling gas passage isolated from an electrolyte.

[Conventional technology]

A fuel cell is a device that directly converts the chemical energy of fuel into electrical energy, and has attracted attention as a new power generation device because of its high thermal efficiency, low noise, electrical noise, and low harmful emissions. ing. This system extracts electricity chemically by supplying fuel and oxidizer between electrodes that sandwich an electrolyte, and is highly effective regardless of the size of the power generation capacity, and is suitable for small and medium-sized distributed power plants. Research and development is being actively conducted on everything from portable independent power sources.

A fuel cell is operated by causing a reaction to occur due to the supply of reactant gas, but the main body of the portable cell is cooled to remove the heat generated during the reaction and maintain the operating temperature.

There are two types of cooling structures: air-cooled and liquid-cooled. ``As a Bt source, an air-cooled type with a simple system configuration is more advantageous.

The reaction gas supplied to the fuel cell is air as an oxidant, and the fuel is reformed gas from a solvent reformer in which the reforming raw material is generally placed in a hydrogen-rich gas. - Power is generated by combining it with a feed reformer to form a fuel α-cell power generation device. The off-gas containing unreacted hydrogen discharged from the fuel cell is used as the fuel for combustion in the reformer.

By the way, in order to operate an air-cooled fuel cell efficiently, for example, in the case of a phosphoric acid type fuel cell, the operating temperature of the cell is usually 190"C.
(It is operated with this condition maintained, but when starting from a stop condition, the temperature must be maintained to the extent that a small amount of carbon monoxide in the reformed gas does not adversely affect the electrode catalyst of the battery, e.g. 140℃ or higher. It is necessary to raise the temperature of the battery.For this reason, air-cooled fuel cells are equipped with a starting device necessary for raising the temperature.

A system diagram of an air-cooled fuel cell power generating apparatus having such a configuration is shown in FIG. In the figure, 1 is a fuel reformer, and liquid fuel such as methanol as a reforming raw material is supplied from the outside to a vaporizer 2.
The vaporized gas is heated by the combustion gas from the burner 3 and vaporized, and this vaporized gas is heated by the combustion gas from the burner 3 in the reactor 4 filled with a reforming catalyst to form hydrogen-rich scum. This reformed gas is supplied to the fuel electrode 11 of the air-cooled fuel cell 10 via the fuel supply pipe 5. In addition, in the burner 3, the combustion air supplied by the combustion air blower 6 and the off-gas supplied from the fuel electrode 1 of the fuel cell 10 via the off-gas supply pipe 7
- Burning takes place.

In the air-cooled fuel cell 10, the above-mentioned reformed gas is supplied to the fuel electrode 11, and an air blower 8 for reactant gas is supplied to the oxidizer electrode 12.
It is operated by supplying air and generates electricity through battery reactions. Reference numeral 13 denotes a cooling plate having a heat medium passage (which becomes a cooling medium passage during operation), and a circulation pipe 15 equipped with a blower 9 for cooling and heating is provided via the cooling plate 13.
A suction pipe 1 equipped with a discharge pipe 16 branching from the circulation pipe 15 at the outlet of the cooling plate 13 and a regulating valve 18 at the suction part of the blower 9.
7 is provided. Note that a heating heater 19 is provided at the discharge portion of the blower 9 to heat the air discharged from the blower 9.

In order to start up an air-cooled fuel cell lO with such a configuration, the temperature of the fuel cell main body must be increased to avoid poisoning of the electrode catalyst as described above.For example, in the case of a phosphoric acid type fuel cell, the temperature must be increased to
Since it is necessary to raise the temperature to approximately
At the same time, the air is heated by the heater 19 to become hot air as a heat medium, and the air is sent to the cooling plate 13ζ to raise the temperature of the pond body to a predetermined temperature. The hot air circulates and flows through the circulation pipe 15, and the opening degree of a discharge damper (not shown) provided in the discharge pipe 16 is adjusted so that the same amount of air as taken in from the regulating valve 18 is discharged from the discharge pipe 16. adjust. Note that the circulating flow rate of the hot air is set to several times the discharge flow rate to increase the amount of heat-transferring hot air at the cooling plate 13 so that the temperature of the fuel cell body can be raised evenly.

When the temperature rise is completed, the reformed gas from the fuel reformer 1 and the air from the reaction gas air blower 8 are respectively supplied to the fuel cell 10.
The fuel is supplied to the fuel electrode 11 and the oxidizer electrode 12 to operate the fuel cell. Note that the fuel cell is cooled during operation by stopping the heater 19 and circulating air through the circulation pipe 15.

Figure 3 shows a different conventional example of increasing the temperature of the fuel cell body.
In the figure, the combustion gas from the starting burner 2 is supplied to the heat exchanger tube a of the heat exchanger tube in the middle of the circulation pipe 15 (a heat exchanger tube is inserted and attached to the starting burner 2). 2]
Fuel such as a liquid raw material for the fuel reformer 1 is supplied from a fuel supply pipe (not shown) and air supplied by a combustion air blower n.

With this configuration, the hot air circulates through the circulation pipe 15 in the same manner as in the conventional example shown in FIG. , the temperature of the fuel cell body is raised via the cooling plate 13.

[Problem that the invention seeks to solve]

When the temperature rises during startup of the air-cooled fuel cell, the circulation pipe 1
The method of obtaining hot air by providing a heater 19 in the heater 19 and heating the circulating air requires a large amount of power to be supplied to the auxiliary equipment including the heater 19 and the like, which has the disadvantage that the auxiliary power source becomes large. In addition, a method of inserting a heat exchanger cylinder into the circulation pipe line 15 and exchanging heat with the combustion gas from the starting burner 21 through the heat transfer tube to heat the circulating air and obtain hot air is a gas method. Since heat exchange is performed with gas, the disadvantage is that the heat exchanger becomes large.

An object of the present invention is to provide a temperature raising device that can efficiently raise the temperature of an air-cooled fuel cell once upon startup using a simple device.

[Means for solving problems]

In order to solve the above problems, according to the present invention, heat i is isolated from the electrolyte and supplied with a reaction gas and a heat transfer medium.
In the heating device for an air-cooled fuel cell that heats up a fuel cell having a body passage by supplying the heat medium passage to the heat medium passage through a supply pipe line having a blower, the heat medium is supplied to the supply pipe line on the blower suction side. A starting burner for supplying air and an air supply means for mixing air with the heat medium from the burner shall be provided.

[Effect]

To raise the temperature of an air-cooled fuel cell, combustion gas from the combustion of fuel in a startup burner is used as the heat medium supplied to the heat medium passage, but since the combustion gas is high temperature, an air supply installed in the supply pipe is used. The combustion gas is cooled by room-temperature air sucked in from the atmosphere to a temperature suitable for raising the temperature of the fuel cell.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a system diagram of an air-cooled fuel cell power generation system equipped with a temperature raising device according to Embodiment 1 of the present invention, and the same parts as those in the conventional example shown in FIGS. 2 and 3 are given the same reference numerals. Therefore, the explanation thereof will be omitted. In FIG. 1, a starting burner 21 is provided via a separate pipe on the suction side of the cooling/heating blower 9 provided in the circulation pipe 15 which is a supply pipe, and the starting burner 21 is used to burn fuel. The combustion gas crossing the pipe is sent to the circulation pipe 15 via a pipe. Note that 26 is a valve that supplies combustion air to the starting burner 21. In addition, a pipe line 5 branched from the pipe line 24
A regulating valve 'A' is provided as an air supply means.

With this configuration, when starting the air-cooled fuel cell 10 from a stopped state (when starting the air-cooled fuel cell 10 from a stopped state), the valve 2G is opened and the blower 9 is driven to cause the starting burner 21 to suck atmospheric air as combustion air. Then, a fuel such as methanol is sent from a fuel supply pipe (not shown) to the starting burner 21, and the fuel is combusted by the intake combustion air to generate combustion gas.This combustion gas is sent to the blower 9 through the pipe U. The atmospheric air is sucked in and circulated through the circulation pipe 15 to raise the temperature of the fuel cell 10.At this time, the opening degree of the regulating valve n is adjusted so that the atmosphere is passed through the pipe 6.
The combustion gas is cooled to a temperature suitable for raising the temperature of the fuel cell 10, and the temperature of the fuel cell 10 is raised. This is because the combustion gas has a high temperature. For example, when methanol is burned at an air-fuel ratio of 1.2 to 1.5, the temperature of the bisque gas is 500.
℃ or higher, so it is cooled by room-temperature air sucked in from the regulating valve n and combusted, taking into account the heat resistance temperature of the components that make up the fuel cell 10, for example, about 200℃ in the case of phosphoric acid type. This is to keep the gas temperature below 200°C.

Note that when the temperature of the fuel cell 10 rises to a predetermined temperature, the starting burner 21 is stopped, and the valve 26. Adjustment valve n is closed to keep the temperature of the fuel cell constant.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the temperature of the air-cooled fuel cell is raised by the combustion gas from the startup burner, and the air supply means supplies room-temperature air to supply high-temperature combustion gas. Since the temperature is increased by cooling the fuel cell to a temperature suitable for raising the temperature of the fuel cell, the temperature of the fuel cell can be raised efficiently using a simple device.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an air-cooled fuel cell power generation device equipped with a temperature raising device according to an embodiment of the present invention, FIG. 2 is a system diagram of an air-cooled fuel cell power generation device equipped with a conventional temperature raising device, and FIG. The figure is a system diagram of an air-cooled fuel cell power generation device equipped with a different conventional temperature raising device. 1: Fuel reformer, 9 nibs, 6 wa, 10: Air-cooled fuel cell,
13: Cooling plate with heat medium passage, 15: Supply pipe line, 2
1: Starting burner, 27 = Regulating valve as air supply means.

Claims (1)

[Claims] An air-cooled fuel that heats a fuel cell having a heat medium passage that is isolated from an electrolyte and is supplied with a heat medium independent of a reaction gas, by supplying a heat medium to the heat medium passage through a supply pipe having a blower. In the battery temperature raising device, a starting burner that supplies the heat medium to the supply pipe line on the blower suction side;
1. A temperature raising device for an air-cooled fuel cell, comprising an air supply means for mixing air with a heat medium from the burner.