In this paper, the possibility of achieving a stable fluidised bed made of the cenospheres was examined. Cenospheres are the waste material from hard coal power plants. This material is perfectly spherical, and it is thin-walled and filled with gases (mainly CO2, N2). Because of their low density, particle size and sphericity, cenospheres can be easily fluidised even at low flow rates of the fluidising medium. Moreover, the application of acoustic waves during the fluidisation of cenospheres removes the apparent effect of double stationary states and moves the minimum fluidisation velocity into lower gas flow rates.
