The invention provides a combined heat and power plant with an integrated gas
production system. The combined heat and power plant contains a steam reformer
heated with a gas burner which converts a mixture of hydrocarbons and water vapour
into a reformate gas stream containing hydrogen and carbon monoxide. The plant
further contains a reactor system with several stages for removing carbon monoxide
from the reformate gas stream. The plant also contains a heat exchanger for removing
heat energy from the reformate gas stream and a fuel cell unit for producing electrical
energy by catalytic reaction of the hydrogen contained in the reformate gas with
oxygen in the fuel cell, wherein the reformate gas stream is supplied to the anode
in the fuel cell unit and the anode waste gas is taken to the gas burner of the
steam reformer as fuel, via a gas pipe. The reactor system for removing carbon
monoxide from the reformate gas stream contains, according to one embodiment of
the invention, a low temperature shift reactor and a downstream methanisation reactor
and the heat exchanger for cooling the reformate gas stream leaving the steam reformer
to the inlet temperature of the low temperature shift reactor is located in the
reformate gas stream between the steam reformer and the low temperature shift reactor.
This combined heat and power plant is operated according to the invention in such
a way that the reformate gas contains 5 to 10 vol. % of unreformed hydrocarbon
which enables the flame in the gas burner to be monitored using an ionisation detector
when burning the anode waste gas in the gas burner of the steam reformer.
