JPS63248075A - Fuel cell reformer - Google Patents

Abstract

PURPOSE:To surely control the temperature of a reformer to efficiently operate a plant and to decrease environmental pollution by installing a combustion furnace which uses flammable material-containing gas in the outlet of a fuel cell as main fuel, a heat exchanger for heat recovery, and a reformer of methanol vapor. CONSTITUTION:A combustion furnace 21 which uses falamble material-containing gas in the outlet of a fuel cell as main fuel is installed. A heat exchanger comprising a heater 22, an evaporator 23, a heating medium evaporator 24 or a heating medium heater, denitration equipment 25, and an air preheater 25 is installed. A methanol heater 31 using steam as power source, a methanol evaporator 32, and a reformer 27 of methanol vapor are installed. These facilities are connected with pipelines. Since the pressure of heating medium can easily be controlled with a pressure control valve 47, the temperature of the reformer 27 is surely controlled. By combining the methanol evaporator 32, the heating medium evaporator 24, and the air preheater 26, rational, effective heat recovery is made possible and a plant is efficiently operated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel reformer, and more particularly to a fuel reformer using methanol reformed gas as a main fuel.

[Prior Art and Problems] Conventionally, many systems have been proposed for reforming methanol vapor and utilizing it in fuel cells. Second
The figure is an explanatory diagram of a methanol steam reformer.

1 in the figure is a fuel cell consisting of seven nodes, an electrolyte, a cathode, etc. A water supply tank is provided near the fuel cell 1 to process water supply.

A fuel reformer 2, an air treatment bag ft3, and a condenser 4 are arranged near the fuel cell 1, respectively.

The fuel cell 1 is supplied with reaction air 5 from the air treatment device 3 and hydrogen-rich gas 6 from the fuel reformer 2. The fuel reformer 2 is supplied with heating fuel 7 from the fuel cell 1, steam 8, air 9, and methanol 10 from the water tank. Reaction product water IJ is supplied from the fuel cell 1 to the air treatment device 3. Further, a circulation pump 12 is installed in the piping connecting the water supply tank and the condenser 4, and water vapor 13 flows from the water supply tank to the condenser 44.
From the condenser 4, cooling air is sent to the water tank.

However, as shown in the second factor, the conventional devices are only conceptual, and the current state is that no specific and detailed information regarding the configuration of the device has been published.

The present invention has been made in view of the above circumstances, and it is possible to reliably control the temperature of a methanol vapor reforming reactor, and
The purpose of the present invention is to provide a fuel reformer that can greatly contribute to increasing the efficiency of a plant through effective heat recovery.

[Means for Solving the Problems] The present invention provides a fuel reformer for a fuel cell that uses methanol reformed gas as the main fuel, and a combustion furnace that uses combustible content-containing gas at the outlet of the fuel cell as the main fuel. , a heat exchanger consisting of at least a heater, an evaporator, a heat medium evaporator or heat medium heater, a denitrification device, and an air preheater is provided for heat recovery, and a methanol heater and a methanol evaporator using water vapor as a heat source. It is recommended that a methanol vapor reforming reactor be provided, and that the means for connecting the above-mentioned components be restricted.

[Operations] According to the present invention, the temperature of the reforming reactor can be reliably controlled, the efficiency of the plant can be increased through rational and effective heat recovery, and the pollution can be reduced.

[Example] Hereinafter, one embodiment of the present invention will be described with full reference to FIG.

Here, FIG. 1 is an overall system diagram of the methanol reformer.

The methanol reformer according to the present invention mainly includes a combustion furnace 2.
1. A first heat conversion section composed of a superheater 22, an evaporator 23, a heat medium evaporator 24, a denitration device 25, and an air preheater 26, and a methanol vapor reforming reactor heated by the heat medium vapor. 27, a second heat exchange section consisting of a heat medium supply pipe 28, a heat medium return pipe 29, a vent drum 30, etc., a heater 3 using superheated steam as a heat source, and a methanol evaporator 32. and a third heat exchange section.

The combustion furnace 2 is provided with a burner 33 and a burner wind box 34, and combustion air 35 is supplied to the burner wind box 34 from the outlet of the air preheater 26. The denitrification device 25 is provided on the gas downstream side of the heat medium evaporator 24 and functions to reduce 7l-NOx generated in the combustion furnace 21. Note that the denitrification device 25 may be arranged in the middle of the heat medium evaporator 24 or on the gas upstream side depending on the level of the gas temperature.

A mixer 36 is provided between the heater 31 and the reforming reactor 27, and the distance between the mixer 36 and the heater 31 is 1g! A fourth regulating valve 37 and a second regulating valve 38 are connected to each other by a pipe 39. The piping 39 between the superheater 22 and the regulating valves 37 and 38 is connected by a steam pipe 4 with a steam bypass valve 40 interposed therebetween. Between the heat medium vapor drum 24a of the heat medium evaporator 24 and the reforming reactor 27, the heat medium supply '
Connected by #28. Here, the reforming reactor 27
has a so-called shell-and-tube configuration, and methanol vapor flows inside the catalyst insertion tube 42.
The outside of 2 is in contact with a heating medium, and the reforming reaction is carried out by receiving heat from the heating medium. The reforming reactor 22
The heat medium return pipe 29, the condenser 43, the storage tank 44, and the pump f45 are located between the heat medium vapor drum 24 and the heat medium vapor drum 24.
Nine pipes 46 are provided between the two. Further, the reforming reactor 27 and the condenser 43 are connected by a pipe 48 with a pressure regulating valve 47 interposed therebetween. Further, a pipe 50 with a pent valve 49 interposed therebetween is connected to the vent drum 30, and a part of the deteriorated heat medium vapor is removed by these pipes.

Next, the operation of the above device will be explained.

First, the burner 33 and burner box 34 of the combustion furnace 21 burn combustible gas recovered from the fuel cell as main fuel. Here, combustion air 35 is supplied to the burner wind box 34 from the outlet of the air preheater 26, and low 02 combustion is performed inside the combustion furnace 21.

At the outlet of the combustion furnace 21, the gas temperature is usually 10
Since the temperature is around 00°C, primary heat recovery is performed by the superheater 22 and the evaporator 23 to lower the gas temperature slightly.

Thereafter, the gas is allowed to flow into the heat medium evaporator 24 . this is,
Generally, as a heating medium, a substance such as diphenyl which has a property of relatively low latent heat of vaporization is used, but in order to prevent quality deterioration of the heating medium, it is preferable to heat with gas as low as possible. It's a good thing.

A part of the generated water vapor is transferred to the steam pipe 41, v! 4. The methanol vapor is passed through a regulating valve 37 and reaches a heater 3 to heat the methanol vapor. Additionally, the vapor enters methanol evaporator 32 to evaporate liquid methanol. After the methanol evaporator 32 performs heat exchange and becomes drain, it is returned to the condenser (not shown).

In addition, the remaining part of the water vapor passes through the regulating valve 38 to the mixer 3.
6 and used as added steam for methanol steam reforming.

The heat medium vapor generated in the heat medium evaporator 24 is guided to the reforming reactor 27 via the heat medium vapor drum 241 and the heat medium supply pipe 28 . Here, methanol vapor flows inside the catalyst insertion f42 of the reforming reactor 27, the outside of which is in contact with the heating medium, and receives heat from the heating medium to perform a reforming reaction. On the other hand, for heat exchange! The condensed heat medium is returned to the storage tank 44. In addition, some of the deteriorated heat medium vapor can be removed by the vent dom 30 and the vent valve 49.

The pressure of the heating medium vapor is controlled by a pressure FAgl valve 47. The heat medium vapor at the outlet of the pressure regulating valve is cooled by the condenser 43, returned to the storage tank 44, and then pressurized by the pump 45 and supplied to the heat medium vapor drum 24a. In this way, since the pressure of the heat medium vapor can be easily adjusted, the temperature of the heat medium vapor can be reliably controlled.

Methanol supplied from the methanol inlet 51 passes through the methanol evaporator 25 and heater 31 to become methanol vapor, and after water vapor is added to it in the mixer 36, it enters the reforming reactor 22, where it is converted into hydrogen and nitrogen. The reformed gas 52 is taken out to the outside.

Further, the combustion gas that has undergone heat exchange in the air preheater 26 is released into the atmosphere from a chimney (not shown).

In general, the appropriate operating temperature level for a methanol reforming catalyst is 200 to 400°C, and it is highly temperature dependent. This is very suitable from the viewpoint of exhibiting performance and maintaining the activity of the catalyst.

The residual oxygen concentration in normal combustion gas is 5% by volume.
Since the amount of heat transfer is kept below 100%, there is no danger of an explosion even if the heating medium were to leak into the flue.

Although the above embodiment describes the case where heat medium vapor is generated, the same objective can also be achieved by combining a liquid heat medium circulation method (a method that does not evaporate) in place of the heat medium vapor method.

Therefore, the present invention has the following effects.

(1) Since the pressure of the heat medium vapor can be easily controlled by the pressure regulating valve 42, the temperature of the methanol vapor reforming reactor 27 can be reliably controlled.

(2) By combining the methanol evaporator 32, the heat medium evaporator 24, and the air preheater 26, rational and effective heat recovery can be performed, which can greatly contribute to increasing the efficiency of the plant.

(3) By installing the denitrification device 25 in an appropriate position, it is possible to reduce pollution.

(4) Since the heat medium evaporator 24 is placed in a relatively low temperature gas region, high reliability can be achieved.

[Effects of the Invention] As detailed above, according to the present invention, the temperature of the reforming reactor can be reliably controlled, the siblants can be made highly efficient through effective heat recovery, and pollution can be reduced. Highly reliable fuel reform 3! j device f can be provided.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing the entirety of a methanol steam reforming apparatus according to one embodiment of the present invention, and FIG. 2 is a system diagram showing the entirety of a conventional methanol steam reforming apparatus. 21... Combustion furnace, 22... Superheater, 23... Evaporator, 23m... Steam drum, 23b... Evaporator lower drum, 24... Heat medium evaporator, 241... Heat medium vapor drum, 24b... Heat medium evaporator lower drum, 25...
- Denitrification device, 26... Air preheater, 27... Reactor, 28... Heat medium supply pipe, 29... Heat medium return pipe, 30
...Vent drum, 31...Heater, 32...Methanol evaporator, 37°38...v4! ! Valve, 40・
...Steam bypass valve, 41...Steam pipe, 42...Catalyst insertion pipe, 43...Condenser, 44...Storage tank, 45...Pump.

Claims (1)

[Claims] In a fuel reformer for a fuel cell that uses reformed methanol gas as the main fuel, a combustion furnace that uses gas containing combustibles at the fuel cell outlet as the main fuel is installed, and a heater, evaporator, and heat medium evaporator are installed for heat recovery. A heat exchanger consisting of at least a heat exchanger or heat medium heater, a denitrification device, and an air preheater is provided, a methanol heater and a methanol evaporator using steam as a heat source are provided, a methanol vapor reforming reactor is provided, and a methanol vapor reforming reactor is provided. A fuel reformer characterized in that a means for connecting each of the above members is provided.