Analysis of Fluid Dynamics Behavior of Conical Spouted Bed in Presence of Pastes

A conical spouted bed (CSB) was employed to obtain the drying and fluid dynamics data in the presence of egg paste and glycerol for a range of operating conditions. In this case, egg paste was added continuously into the bed at several feed rates, whereas glycerol was fed in batch process. Under these conditions, minimum spouting velocity, pressure drop, fountain height, paste concentration, and film moisture content were evaluated. The results showed that ΔPs and Ums decreases with increasing glycerol concentration; however, Ums presented an opposite behavior for egg paste. Fountain height increases with increasing glycerol into the bed. Film moisture content and homogenized egg paste concentration were maintained uniformly scattered at all points of the bed. In addition, the methodology proposed by Schneider and Bridgwater[ 1 Schneider , T. ; Bridgwater , J. The stability of wet spouted beds . Drying Technology 1993 , 11 ( 2 ), 277 – 301 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar] ] showed itself to be appropriate for predicting stable spouting regimes. Furthermore, most of the experimental data of this study was compared to other results and to some empirical and mechanistic models reported in literature. Thus, our experimental data could be well described by an empirical model like Passos and Mujumdar's[ 2 Passos , M.L. ; Mujumdar , A.S. Effect of cohesive forces on fluidized and spouted beds of wet particles . Powder Technology 2000 , 110 , 222 – 238 . [CROSSREF] [Crossref], [Web of Science ®] , [Google Scholar] ] model. On the other hand, the mechanistic model proposed by Cunha[ 3 Cunha , F.O. Contributions to the analyses of drying of pastes in spouted bed with inert particles . M.Sc. Thesis , Federal University of Sao Carlos , Brazil . 1999 . ( In Portuguese ). [Google Scholar] ] overestimated the theoretical minimum spouting velocity at a range of values of 10 to 25%.