EFFECT OF CHEMISORBED WATER ON BED VOIDAGE OF HIGH-TEMPERATURE FLUIDIZED-BED

Minimum fluidization voidage in the beds of three kinds of silica is i nvestigated at elevated temperatures up to 1223 K experimentally and t heoretically. The bed voidage depends not only upon the operating temp erature but also upon the humidity of fluidizing gas. Experimental res ults and theoretical consideration on the change in the bed voidage wi th temperature and/or humidity demonstrate that this change is caused by the adhesion force of silica particles originating from the change in the concentration of siloxane groups on the surface of the particle s.