Reforming furnace

A reforming furnace comprising:

• a burner combusting downwards and provided at a center portion of a ceiling wall of a furnace body having a cylindrical lateral wall disposed between the ceiling wall and a bottom wall;
• a reforming reaction tube provided in a circumference of the burner in suspension from the ceiling wall and configured to carry out a steam reforming treatment on a hydrocarbon-based gas as a source gas;
• and
• a discharging portion provided as an opening at an upper side portion of the lateral wall for discharging combustion gas of the burner;
• wherein a cylindrical outer wall is disposed at an outer side portion of the lateral wall between the ceiling wall and the bottom wall;
• wherein, in an outside space formed between the lateral wall and the outer wall, there is disposed a steam generating heat exchanger generating steam or a mixture gas of a source gas and steam to be supplied to an upper portion of the reforming reaction tube;
• wherein at a lower side portion of the outer wall, there is provided an outside discharging opening discharging the combustion gas which flows from the discharging portion through the outside space;
• the reforming reaction tube comprises:
• an outer tube having a closed bottom portion and a supported upper end side;
• an inner tube disposed inside the outer tube, the inner tube having an opened bottom portion and a supported upper end side;
• and
• a plurality of reaction tube portions charged with a catalyst and disposed between the outer tube and the inner tube, the reaction tube portions being disposed side by side with spacing therebetween along a circumference of the burner.