Patent ID: 8622736

Claim:
A recuperator burner ( 1 ) for heating a chamber volume ( 2 ) in which combustion gas is circulated, said recuperator burner comprising: a central fuel supply pipe ( 23 ) for injecting fuel into the chamber volume ( 2 ), a recuperator ( 30 ) disposed annularly around the central fuel supply pipe ( 23 ) for preheating combustion air by means of hot exhaust gas conducted out of the chamber volume ( 2 ) in a counter-current heat exchange with the combustion air supplied to the chamber volume ( 2 ), the recuperator ( 30 ) comprising heat exchanger pipes ( 16 ) with circular inlet end sections mounted in a flange plate ( 12 ), with circular outlet end sections which are bent inwardly toward the central fuel supply pipe ( 23 ) and with flattened straight center sections ( 31 ) providing for a narrow internal pipe gap cross-section ( 34 ) in the center section ( 31 ) for improved heat exchange, and each heat exchanger pipe ( 16 ) having at its discharge end ( 33 ) facing the chamber volume ( 2 ) a reduced diameter end forming a nozzle with a nozzle cross-section ( 35 ) which is smaller than the narrow internal pipe gap cross-section ( 34 ).