EFFECT OF DISTRIBUTOR ON BUBBLE-SIZE IN A CYLINDRICAL FLUIDIZED-BED AT AN ELEVATED-TEMPERATURE

The effects of temperature and distributor on bubble diameter were investigated using a cylindrical fluidized bed of 147 mm in diameter. Three perforated distributors having different holes in diameter and the same ratio of holes to bed area were used. Eruption diameters of bubbles were measured using a high speed video-camera system under the following conditions: bed temperature = 300 and 600 K, bed particles = spherical glass beads of 272/im in average size, excess gas velocity = 1–4 cm/s, and static bed height = 10–42 cm. The bubble diameter at 600 K was larger than that at 300 K. The difference became smaller with increasing the static bed height and with increasing the excess gas velocity. The distributor with larger holes gave larger bubbles. The effect of hole diameter of the distributor on the bubble diameter became insignificant with increasing the static bed height and with increasing the excess gas velocity. © 1991, Taylor & Francis Group, LLC. All rights reserved.