shows the configuration of a CFB boiler and the related flue-gas recirculation system,similar to that of a PC boiler.
Theoretically, the three recirculation options shown in the sketch
(dirty, wet, and dry recirculation) are possible, but material and
species accumulate as a consequence of recirculation, and the dirty
option can be ruled out because of anticipated high particle
loading: some type of particle separator will be necessary in all
systems. It is more uncertain to decide a priori whether to employ