Effect of Temperature on Fine Particle Drying in a Draft‐Tube Conical Spouted Bed

The performance of a draft‐tube conical spouted bed for drying fine particles under batch operating conditions has been assessed at several temperatures using nonporous and open‐sided draft tubes, and the results have been compared with those obtained when operating without a draft tube. In order to ascertain the influence of temperature on drying, experimental runs have been carried out in the 25–300 °C temperature range. The open‐sided draft tube provides the best performance due to the excellent gas‐solid contact attained with this device, which enables shorter drying times. A maximum air temperature of 200 °C is recommended for energy optimization. An open‐sided tube protruding above the stagnant bed by at least 2/3 of the latter's height produces much lower and denser fountains than a tube flush with the upper surface of the bed.