Method and system for regenerating energy from the combustion exhaust gas of an industrial furnace, in particular a glass-melting furnace

摘要

A method of regenerating energy from the combustion exhaust gas of an industrial furnace (2), in particular a glass-melting furnace, includes extracting a combustion exhaust gas stream (8) from the furnace (2), and preheating a combustion-supporting air stream (6), by which to eventually support combustion in the furnace, by heat exchange with the exhaust gas stream; the combustion-supporting air stream is preheated in a first and a second heat-exchange step distinct from each other and conducted in series and one after the other in a first (11) and, respectively, second (12) unit permitting heat exchange between the combustion-supporting air stream (6) and the exhaust gas stream (8); the combustion-supporting air stream (6) is circulated successively in the first unit (11) and then in the second unit (12), so as to be heated to respective increasing temperatures; and the exhaust gas stream (8) is circulated successively in the second unit (12) and then in the first unit (11), so as to be cooled to respective decreasing temperatures.