| 摘要 |
A steam reforming system which uses a primary reforming apparatus including an external combustion reforming furnace to generate a primary reforming reaction gas of mixed gas of hydrocarbon and steam and a secondary reforming apparatus which is an internal combustion reactor reforming apparatus to cause the secondary reforming reaction of the primary reforming reaction gas obtained by the primary reforming step to progress in the presence of air and/or oxygen. A burner assembly of the external combustion reforming furnace has a plurality of burners which heat catalyst pipes and a plurality of heat storage units which preheat the combustion air flows fed to the burners. The burnt exhaust gas of the external combustion reforming furnace heats 2nd heats storage units which preheat combustion, the air flows fed to 2nd burners while the 1st burners are burning and preheats the 1st heats storage units which preheat the combustion air flows fed to the 1st burners while the 2nd burners are burning. The flow passage of the burnt exhaust gas is so controlled as to be selectively switched to a 1st low passage or a 2nd flow passage. The fluid of 10-30 wt.% of the burnt exhaust gas of the external combustion reforming furnace is supplied to 1st and 2nd heat exchangers from the intra-furnace region of the external combustion reforming furnace, and raw material hydrocarbon or hydrocarbon/steam mixed gas and air and/or oxygen are heated by the heat exchange action of the heat exchangers. Reformed gas generated in the system is supplied to a 3rd heat exchanger heats, the hydrocarbon/steam mixed gas in the heat exchanger, and is sent out into a reformed gas sending line. The steam reforming system as described above can achieve a high and econcomical energy efficiency or a manufacturing efficiency of the whole plant. |
