| 摘要 |
In the present invention, a gas flow passage has a closed circulation circuit which bypasses a hydrogen purification unit so that gas is returned and circulated therethrough by a pumping device to a desulfurizer, a reformer, and a CO shift converter, in this order, and a purge gas supply passage for supplying purge gas to the gas flow passage upstream of the pumping device is provided. Prior to a shutdown operation, a purge step is performed in which the gas in the gas flow passage is replaced with the purge gas and the gas flow passage is filled with the purge gas. In a startup operation which is performed prior to a hydrogen purification operation and in which the temperature of the gas in the gas flow passage is raised by operating a heating means, a pressure increasing step is performed in which the pressure inside the closed circulation circuit is increased by supplying the purge gas to the closed circulation circuit from the purge gas supply passage. |
