Abstract
The effects of operational conditions on the drying characteristics of porous materials immersed in the fluidized bed of fluidzing particles with superheated steam weae excamined experimentally and tbeoretically. A brick ball and the glass beads were used as the drying sample and fludizing particles, respectively. N2 gas, which is substitute of air, was also used as the drying gas for the comparison. In calculation, heat and mass transfers in sample were considered. THe temperature of fluidiaed bed and mass velocity of drying gas were changed, respectively in experiment and calculation. There is the period when the temperature of sample center is almost constant in the fluidized bed drying with superheated steam and with hot air, and the temperature is ligber in the case with supertted steam than in the case with hot air. An inversion point of drying time between fltudzed bed drying with supertheated steam and that with hot air appears at about 473 K of bed temperature rathe calculation. The effect of mass velocity of drying gas onthe drying time is very slight when the mass velocity is sufficiently high.
