US Patent:
20110303135, Dec 15, 2011
Inventors:
James W. Birmingham - Wellsville NY, US
James D. Seebald - Wellsville NY, US
Assignee:
ALSTOM TECHNOLOGY LTD - Baden
International Classification:
F23N 3/00
F28D 19/04
F23L 15/02
US Classification:
110341, 110304, 110188, 110190, 165 9
Abstract:
An air preheater is described having an air damper assembly that partially restricts an air inlet and a flue gas damper assembly that partially restricts flue gas inlet during periods of reduced boiler load. Restricting the flue gas inlet reduces the effective surface area of the preheater causing more heat to pass to the cold end of the air preheater , reducing acid condensation and fouling. Restricting the gas inlet , increases gas velocity, thereby eroding accumulations in the air preheater , also reducing fouling. Restricting the air inlet reduces the effective heat transfer surface area of the air preheater, which raises the gas temperature in the cold end of the air preheater and thereby reduces acid condensation and fouling.