Method for starting-up solid oxide fuel cell system

A method for starting-up a solid oxide fuel cell system which comprises a reformer having a reforming catalyst, for reforming raw material for producing hydrogen to produce a reformed gas containing hydrogen, and a solid oxide fuel cell which uses the reformed gas as a fuel, wherein

• a catalyst having partial oxidation reforming function and a catalyst having steam reforming function are used as the reforming catalyst, and
• said method comprises the steps of
• i) increasing the temperature of the catalyst having partial oxidation reforming function, by combustion heat or electricity, to a temperature at which the partial oxidation reforming reaction can proceed,
• ii) conducting the partial oxidation reforming reaction, increasing the temperature of the catalyst having steam reforming function by heat generated from the partial oxidation reforming reaction, increasing the temperature of the solid oxide fuel cell by feeding a combustion gas produced from combustion of the reformed gas to a cathode of the solid oxide fuel cell, and heating the catalyst having steam reforming function by the combustion gas produced from combustion of the reformed gas, and
• iii) reducing the proportion of the partial oxidation reforming reaction or stopping the partial oxidation reforming reaction and performing the steam reforming, after the catalyst having steam reforming function is heated to a temperature at which the steam reforming reaction can proceed.

A method for starting-up a solid oxide fuel cell system which comprises a reformer having a reforming catalyst for reforming raw material for producing hydrogen to produce a reformed gas containing hydrogen, and a solid oxide fuel cell which uses the reformed gas as a fuel, said reforming catalyst being composed of a catalyst having partial oxidation reforming function and a catalyst having steam reforming function, which are separately used in the reformer,

• said method comprising:
• increasing the temperature of the catalyst having partial oxidation reforming function mainly by combustion heat or electricity to a temperature at which a partial oxidation reforming reaction can proceed, thereby conducting the partial oxidation reforming reaction;
• increasing the temperature of the catalyst having steam reforming function mainly by the heat generated due to the partial oxidation reforming reaction;
• increasing the temperature of the solid oxide fuel cell mainly by feeding a gas produced in the reformer to an anode of the solid oxide fuel cell;
• combusting a gas discharged from the anode of the solid oxide fuel cell;
• heating the catalyst having steam reforming function by heat generated from the combustion for conducting a steam reforming reaction;
• and
• reducing a proportion of the partial oxidation reforming reaction to the steam reforming reaction or stopping the partial oxidation reforming reaction, thereby predominantly conducting the steam reforming reaction, after the catalyst having steam reforming function is heated to a temperature at which the steam reforming reaction can proceed.