Experimental analysis of a mechanically stirred spouted bed dryer

In order to increase the movement of the particles in the annular region of a conical spouted bed, a mechanical stirrer was incorporated. This led to a study of the fluid dynamics of the conical spouted bed of inert particles under different operating conditions: mass of inert particles, ratio of in ert particles to suspension volumes, type of stirrer (2 designs) and stirre r speed. The action of the stirrers resulted in increased movement of the particles, especially at low rpm values (less than or equal to 90 rpm), with the loss of the annular region, and thus approaching the beds behavior to that of a fluidized bed. To characterize this novel type of Spouted beds, the "minim um spouting flow" (Q(ms)) parameter which is used usually was replaced by t he "minimum pseudo-fluidizing flow" (Q(mpf)) The value of Q(mpf) decreases when the agitation in the bed increases. A correlation for Q(mpf) with the different operating conditions was developed. Drying suspensions in the stirred spouted bed shows a considerable increase of drying capacity, over units without agitation.