減圧媒体粒子流動層内における微粒子懸濁物質の乾燥特性

Abstract

Drying characteristics of slurry in a fluidized bed of inert particles （average diameter＝0.12 mm） under reduced pressure were examined. A mixture of distilled water and fly ash （median diameter＝5μm） was used as （model） slurry.To obtain the dry dispersed powder continuously, feed rate of slurry （water flow rate） must be equal to the evaporation rate in the fluidized bed, i.e., the maximum evaporation rate when the water flow rate is equal to the evaporation rate exists. As the powder content in slurry increased, the drying rate became lower. The drying rate was higher as the pressure in the drying chamber decreased, and the temperature in the fluidized bed became lower as the drying rate increased. From these, it was found that the low temperature drying with high drying rate was possible in the fluidized bed of inert particles under the reduced pressure.