Experimental investigation of the heat and mass transfer in a centrifugal fluidized bed dryer

An experimental study of the heat and mass transfer characteristics of wet material in a drying process in a centrifugal fluidized bed (CFB) dryer was carried out. The rotating speed ranged from 300 to 500 rpm. Wet sand, glas s beads and sliced food products were used as the testing materials. The ga s temperature and the wet bulb temperature at the inlet and outlet, as well as the bed temperature, were measured. The moisture contents were determin ed instantaneously by the mass balance method in the gas phase. Influences of the superficial gas velocity, particle diameter and shape, bed thickness , rotating speed of the bed and initial moisture on the drying characterist ics were examined. One empirical correlation which can be used to calculate the heat transfer coefficients of the gas particles in the centrifugal flu idized dryer were obtained. (C) 2000 Elsevier Science S.A. All rights reser ved.