Combined heat and power apparatus with gas producing system and fuel cells and method of operation

Combined power-heating device comprises a reactor system for removing carbon monoxide from a reformate gas stream and contains a low temperature shift reactor and a methanization reactor connected to it; and a heat exchanger arranged between the steam reformer and the shift reactor for cooling the reformate gas stream leaving a steam reformer to the starting temperature of the shift reactor. An Independent claim is also included for a process for operating a combined power-heating device. Preferred Features: The low temperature shift reactor contains a Cu/ZnO shift catalyst. The methanization reactor contains a catalyst containing ruthenium.