Simultaneous drying and cleaning of guava seeds in a spout-fluid bed with draft tube

A half sectional spout-fluid bed column with draft tube was used for the cleaning and drying of guava seeds in one single operation. The process took place on a batch basis with a constant spouting velocity of 1.5 U_ms and an additional annular air flow rate equivalent to 0.5 and 0.7 U _mf. A regression model based on the spouting air temperature T _s, the annular inlet air temperature T_a and the additional annular air flow rate xU_mf was obtained to calculate the drying time. An additional cleaning step was necessary to increase the separation efficiency of the dried pulp from about 70% obtained during the drying process to 84%.