Circulating fluidized bed boiler with improved nitrogen oxide reduction

摘要

The circulating fluidized bed boiler comprises a combustion hearth and a separator cyclone interconnected by a duct which extends along a longitudinal axis and which channels a flow of particles and gas containing nitrogen oxides. It also includes means for injecting into the flow a reagent for reducing nitrogen oxides. Said means comprises at least a first injection tube disposed in a setback of the top portion of the combustion hearth which extends over the duct so as to inject the reagent along the longitudinal axis of the duct in the same direction as the flow.