RADIAL NONUNIFORMITY OF FLOW STRUCTURE IN A LIQUID-SOLID CIRCULATING FLUIDIZED-BED

Electrical conductivity probes were used to measure the radial distrib utions of solids holdup and liquid velocity in a liquid-solid circulat ing fluidized bed. These distributions are found to be non-uniform, un like those in a non-circulating bed. The effects of superficial liquid velocity and particle circulation rate on the radial distributions of bed voidage and liquid velocity are studied. Based on the experimenta l results, a qualitative explanation is given for the difference betwe en the dispersed fluidization and the circulating fluidization. The ef fect of the radial nonuniformity of the flow structure on the reaction s in the liquid-solid circulating fluidized bed reactor is also discus sed.