The invention relates to a method for inter alia to increase the energy and
cost efficiency of a gas power
plant or a thermal heat
plant with CO2 capturing. The power
plant comprises gas
turbine plants (12,12′) comprising compressor units (13,13′) and
turbine units (14,14′) and further comprises a
combustor (10). The
combustor (10) is working in principle with to separate gas part streams where one gas part
stream flows internally through the
flame tube (40) of the
combustor (10), while the other gas part
stream is flowing along the exterior of the
flame tube (40). The first gas part
stream comprises additional air and re-circulated, un-cleaned
flue gas from the combustor (10), said gases being combusted together with fuel inside the
flame tube (40). The second gas part stream comprises cleaned
flue gas which is heated up at the exterior of the flame tube (40) while the flame tube (40) is cooled down. The invention comprises also a power plant, a combustor and a CO2 capture plant.