Scaling and Performance of a Device for Fluidized Bed Entrainment Reduction

Abstract

A device recently proposed for entrainment suppression from a fluidized bed has been studied. Particles projected upward at the bed surface entered a particle diverter which returned them to the bed. Relations were proposed for scaling the particle mass flux field above the device. Experimental studies were done on two geometrically similar flow systems, using fluidized beds with diameters of 9.5 cm and 33.3 cm. Measurements were made of the particulate mass flux and gas velocity in the dilute phase. A probe was developed which determined the particle mass flux by counting electrical pulses produced when particles collided with a metal sensor placed in the flow stream. Air velocity was measured with a rugged hot film anemometer.

The particle mass flux field in the large system was predicted adequately from measurements made in the small system by utilizing the scaling relations. In addition, use of the device resulted in a significantly lower transport disengaging height and a steadier flow than an ordinary fluidized bed.