Particle Population Balances in a Refuse Derived Fuel Fired Circulating Fluidized Bed Combustor

With a population balance model the effects of changes in the operation of a circulating fluidized bed combustor on the bed inventory are simulated. Feeding, discharge and recirculation of solids as well as separation effects in the combustion chamber and in the cyclone are considered. The model predictions are compared with measurements at the refuse-derived fuel incineration plant Neumuenster. The simulation shows that by sieving of the ash withdrawn from the bottom of the combustion chamber and recycling the fine fractions to the bed the non-elutriable fraction of the ash in the bottom zone of the circulating fluidized bed (CF B) can be kept at a low level