Hydrogen generator and fuel cell system using the same

Abstract

Provided is a hydrogen generator which is capable of reducing a size of an entire apparatus and reducing a running cost by utilizing heat of a heat exchanger (1) for hydrogen reforming in a reformer (2), and which can particularly preferably be used in a facility such as a hospital, a restaurant, or a hotel utilizing both steam and electricity, and a fuel cell system using the hydrogen generator. The hydrogen generator includes the reformer (2) for generating hydrogen H2 from a fuel gas G and steam H2O incorporated in a fuel gas passage (12) of the heat exchanger (1) provided with a water pipe (13). The hydrogen generator utilizes a part of heat of the heat exchanger (1) for hydrogen reforming performed in the reformer (2). The hydrogen generator includes the reformer (2), a converter (3) for generating hydrogen from carbon monoxide generated in the reformer and steam, and a CO remover (4) for removing a carbon monoxide gas generated in the converter (3). The reformer (2), the converter (3), and the CO remover (4) are arranged in the flue gas passage (12) of the heat exchanger (1).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a piping block diagram showing a fuel cell system provided with a hydrogen generator according to an embodiment of the present invention;

FIG. 2 is a piping block diagram showing a fuel cell system employing a membrane reactor-type reformer according to another embodiment of the present invention;

FIG. 3 is a sectional diagram showing a catalyst device used for a membrane reactor-type reformer;

FIG. 4 is a schematic diagram showing a formation example of a reformer in the case where a cylindrical body is used as a heat exchanger;

FIG. 5 is a schematic diagram showing an example employing the same heat exchanger as that of FIG. 4 and having a reformer provided outside of the cylindrical body;

FIG. 6 is a schematic diagram showing a formation example of a reformer in the case where a rectangular body is used as a heat exchanger;

FIG. 7 is a schematic diagram showing another formation example of the reformer in the case where a rectangular body is used as a heat exchanger;

FIG. 8 is a schematic diagram showing still another formation example of the reformer in the case where a rectangular body is used as a heat exchanger;

FIG. 9 is a graph showing an inside temperature distribution of a rectangular body used as a heat exchanger by section; and

FIG. 10 is a graph showing an inside temperature distribution of a cylindrical body used as a heat exchanger by section.

Claims

1. A hydrogen generator comprising: a heat exchanger provided with a water pipe;a reformer for generating hydrogen from a fuel and steam, wherein the reformer is incorporated into a flue gas passage of the heat exchanger.

2. A hydrogen generator according to claim 1, wherein the reformer comprises one of a reforming catalyst and a hydrogen separation membrane.

3. A hydrogen generator according to claim 1 or 2, further comprising: a converter for generating hydrogen from carbon monoxide generated in the reformer and steam; and a CO remover for removing a carbon monoxide gas generated in the converter, wherein the reformer, the converter, and the CO remover are arranged in the flue gas passage of the heat exchanger.

4. A hydrogen generator according to claim 1 or 2, further comprising: a converter for generating hydrogen from carbon monoxide generated in the reformer and steam; and a CO remover for removing a carbon monoxide gas generated in the converter, wherein the converter and the CO remover are provided downstream of the reformer and outside the flue gas passage of the heat exchanger.

5. A hydrogen generator according to any one of claims 1 to 4, wherein downstream of the water pipe of the heat exchanger is connected to upstream of the reformer.

6. A fuel cell system provided with a hydrogen generator, comprising a fuel cell connected to downstream of the hydrogen generator according to any one of claims 1 to 5.

7. A fuel cell system provided with a hydrogen generator according to claim 6, wherein a reformed gas from the hydrogen generator is supplied to upstream of the flue gas passage of the heat exchanger.

8. A fuel cell system provided with a hydrogen generator according to claim 6, further comprising: a detector for detecting a concentration of hydrogen or carbon dioxide in a reformed gas supplied from the hydrogen generator to the fuel cell; and adjusting means for adjusting a supply volume of the reformed gas to the upstream of the flue gas passage of the heat exchanger based on a detection result of the detector.