A NEW TECHNIQUE FOR THE EVALUATION OF A CIRCULATING FLUIDIZED-BED MIXING CHAMBER WITH A CENTRAL SOLIDS JET

Many gas-solid reactions an performed in circulating fluidized beds wh ich are either operated in the downer or riser mode. Good gas-solid co ntact in the early stages of the reaction is crucial to such reactors. A simple experimental tool has been developed for rapid, rough charac terization of the gas-solids dispersion at the mixing chamber exit. A simplified momentum probe provides instantaneous pressure signals at s even radial locations. Cross-correlation analysis of these signals res ults in three new indices: a mixing index, a uniformity index and a st ability index. These indices have been successfully applied to the sel ection of the best mixing chamber for a downer. (C) 1998 Elsevier Scie nce S.A. All rights reserved.