NOx Emission Reduction by the Optimization of the Primary Air Distribution in the 235Mwe CFB Boiler

The article presents the results of experimental studies conducted on a large-scale 235 MWe CFB (Circulating Fluidized Bed) boiler, in which the primary air distribution system was modified. The modification was connected with the change of internal geometry of primary air channels as well as internal space of plenum chamber. The obtained results have shown, that the optimization of primary air flow has a great influence on the intensity of the combustion process and the temperature distribution along the height of combustion chamber. As a result, the NOx emission has been reduced by up to ten percent and the temperature profile in the combustion chamber has been revealed to be more uniform.