Hydrogen generator and fuel cell system

Abstract

A hydrogen generator according to the invention comprises: a combustion gas passage () configured to flow combustion gas coming from a combustor; a preheat-evaporator () which is supplied with a material gas and water and configured to evaporate the water and heat the material gas by heat transmitted from the combustion gas passage and a carbon monoxide reducer () through partition a wall; a reformer () configured to generate reformed gas from the material gas and steam fed from the preheat-evaporator by using a reforming catalyst () and heat transmitted from the combustion gas passage through the partition wall; the carbon monoxide reducer () configured to remove carbon monoxide from the reformed gas fed from the reformer by a carbon monoxide removing catalyst (); a cylindrical body () closed at both ends thereof having an internal space is divided by the partition walls (), (), (), () to form the combustion gas passage, preheat-evaporator, reformer and carbon monoxide reducer within the cylindrical body (), wherein a heat transmission buffering section () is formed between the preheat-evaporator and the carbon monoxide reducer such that the partition wall () that defines the preheat-evaporator and the partition wall () that defines the carbon monoxide reducer are opposed to each other with a space therebetween.