NOVELTY - A vacuum vessel comprises a spiral piping for reforming, and a catalyst for ignition arranged at the upper part. Raw material for reforming is supplied through the piping, for heat-reforming. A fuel is supplied through a fuel introduction pipe into the upper part of the chamber. By catalyzed combustion of fuel on the surface of the piping, the reforming raw material inside is heated up and reformed.    USE - For vaporizing gas such as hydrogen in fuel cells, by reforming raw material such as methanol and water.    ADVANTAGE - The atmosphere inside the vaporizer is heated up to a higher temperature, by the heating apparatus. By the catalyzed combustion of fuel, the raw materials for reforming on the surface of the spiral piping, can be directly heated through the piping. Cost of operation is reduced and hot methanol gas for reforming is formed efficiently.    DETAILED DESCRIPTION - A vacuum vessel (1) has a spiral piping for reforming (16), and comprises a catalyst for ignition (18) arranged at the upper part. A fuel introduction pipe (10) is arranged at the upper part of the vacuum vessel. Raw material for reforming (47) is supplied through a piping (6) into the spiral piping for heat-reforming. A fuel is supplied through the fuel introduction pipe into the upper part of the chamber. By catalyzed combustion of fuel on the surface of the piping, the reforming raw material in the spiral pipe is heated up and reforming reaction is carried out.    DESCRIPTION OF DRAWING(S) - The figure shows a sectional view of the vaporizer.    Vaporizer (1)    Vacuum vessel (2)    Feed pipe for raw material for reforming (6)    Fuel feed pipe (7)    Air feed pipe (8)    Vaporized gas discharge pipe (12)    Combustion gas discharge pipe (14)    Spiral piping (16)    Catalyst for ignition (18)    Outer wall (20)    Middle wall (21)    Space (22)    Outer piping (27)    Inner piping (28)    Methanol (41,45,50)    Air (43)    Raw material for reforming (47)    Combustion gas (52)