Canadian Journal of Chemical Engineering, Vol.87, No.5, 695-703, 2009
LIQUID-PARTICLE SURFACE PROPERTIES ON SPOUTED BED COATING AND DRYING PERFORMANCE
Polymeric coating has been applied to particles for several reasons, which goes from enhancing product esthetics to control the release of chemicals. Spouted beds are among the equipments widely used to coat particles. Its choice is justified by the cyclic movement of the particles in stable spouting resulting in product homogeneity and good solid-fluid contact with high heat and mass transfer rates. Also, the spouted bed with inert particles is an alternative to drying pastes due to its low cost and applicability to low scale production. This work presents results of coating and drying efficiencies for different systems that combine 04 different solids and 03 formulations of suspensions. Materials having different surface tension were chosen and suspensions with varying surface tensions were formulated, resulting in different wettabilities (quantified by contact angles measurements). The results show the direct influence of these properties on the coating and drying performances.