| 摘要 |
PROBLEM TO BE SOLVED: To suppress the carbon precipitation reaction in the reforming catalyst layer of a fuel processing system by stopping the feed of fuel gas to the fuel processing system, and then immediately introducing an inert gas such as nitrogen and steam into the system to purge the fuel gas. SOLUTION: In the stopping operation of a plant, after a fuel gas flow regulating valve 12 is closed to stop a fuel gas, a steam flow regulating valve 20 is opened to carry steam from a steam feed piping 19 simultaneously with the opening of an inert gas shut-off valve 24 for introduction of an inert gas. In this case, the steam flow rate is preferably regulated to introduce steam of a volume from the connection part between a fuel gas feed piping 11 and an inert gas feed piping 23 to the connection part between the steam feed piping 19 and the piping of a fuel processing system or more. The introduction of steam is stopped after the fuel gas is stopped, and the passing of the inert gas is continued until the steam left in the plant is discharged to the outside. |
