SOUND ASSISTED FLUIDIZED BED COMBUSTION

The combustion and/or gasification of solid fossil fuels in fluidized beds may be considered a technology already mature (Abdulally I. F. and Reed K., 1995). However its extension to the case of not conventional fuels: Refuse Derived Fuel (RDF), Tyre Derived Fuel (TDF), biomass and industrial or civic residues, is the challenge to the operators of the sector and to researchers (Anthony E. J., 1995). The main feature of such fuels and, more in general of high-volatile fuels, is the generation of large amount of fine particles during their conversion. A limit situation is the case of TDF: the total amount of carbon present in the bed under steady state operation is made of fine particles, whatever the feed size (Salatino P., et al., 1997). On the other hand the efficiency and the environmental impact of the combustion is mainly related to elutriation of solid carbon. Aim of the present work is to investigate the practical usefulness of using sound assisted fluidized beds to increase carbon conversion degree and to reduce the amount of fine particles escaping the reactor as unreacted carbon, when fuels of different characteristics are used.