Resumo

KOZANOGLU, B.; WELTI, J.; MANCEBO, M.  e  MARTINEZ, F.. Effect of Applying Different Vacuum Levels in Two Drying Periods in a Fluidized Bed. Inf. tecnol. [online]. 2004, vol.15, n.2, pp. 35-40. ISSN 0718-0764.  doi: 10.4067/S0718-07642004000200007.

A series of vacuum-fluidized bed drying experiments was carried out, employing variable operating pressures such that, the combination of the effects of decrease in the transport capacity of the exterior medium and the enhancement of the internal diffusivity results in favor of the drying process. Two solids with different structures were used, including porous silica gel particles and compact lentil particles. In these experiments, different vacuum operating pressures were employed for each drying rate period. It was observed that in the case of the drying process for porous silica gel particles, increasing the operating pressure during the decreasing drying rate period results in a higher drying rate. It is concluded that the interior resistances dominate the process in the decreasing drying rate period, where the transport capacity of the outside medium also gains importance

Palavras-chave : fluidized bed; drying process; vacuum; drying rate periods; diffusivity.