Catalyst combustion system, fuel reforming system, and fuel cell system

A catalyst combustion system comprising:

• a closable first fuel supply line which supplies a fluid containing a first fuel;
• a closable first oxidizer supply line which supplies a fluid containing a first oxidizer for the first fuel to be combustible therewith under assistance of a catalyst;
• a second fuel supply line which supplies a fluid containing a second fuel different from the first fuel;
• a second oxidizer supply line which supplies a fluid containing a second oxidizer for the second fuel to be combustible therewith under assistance of the catalyst;
• and
• a catalyst combustor configured to alternately perform a first catalyst combustion between the first fuel and the first oxidizer and a second catalyst combustion between the second fuel and the second oxidizer, and to supply as a thermal medium a fluid containing one of a combustion product of the first catalyst combustion and a combustion product of the second catalyst combustion, wherein
• the catalyst combustor comprises a first catalyst combustion portion connected to the first fuel supply line and the first oxidizer supply line, a second catalyst combustion portion connected to the second fuel supply line and the second oxidizer supply line, and a fluid communication portion connecting the first catalyst combustion portion and the second catalyst combustion portion to each other, and
• has a fixed relationship provided among a fluid resistance of the first catalyst combustion portion, a fluid resistance of the second catalyst combustion portion, and a fluid resistance of the fluid communication portion, whereby substantially the first catalyst combustion is cased to occur simply in the first catalyst combustion portion, and the second catalyst combustion is caused to occur in the first catalyst combustion portion and the second catalyst combustion portion.