Determination of minimum spouting velocities in conical spouted beds

Minimum spouting velocities in conical spouted beds have been obtained from pressure drops versus the superficial gas velocity curves, based on both increasing and decreasing the superficial gas velocity. It has been shown that the minimum spouting velocity from decreasing the superficial gas velocity is lower than from increasing the superficial gas velocity in most cases. This phenomenon is similar to that in conventional spouted beds and different from the early works. The experimental results also showed that there isn't significant difference in the pressure drop and U-ms under identical operating conditions between semicircular and circular conical spouted beds, and the same U-ms can be obtained from absolute pressure drops at any position above the gas inlet. The U-ms is found-to increase with increasing the cone angle and static bed height, as well as the gas inlet diameter to a less extent.