Minimum spouting velocity of fine particles in fountain confined conical spouted beds

Abstract

A novel internal device called fountain confiner has been developed, which stabilizes the system and allows operating with fine particles, even without any type of draft tube. Given the stability this device confers upon the system, lower minimum spouting velocities than in conventional systems are required, and therefore the correlations in the literature overestimate this hydrodynamic parameter. Accordingly, runs have been carried out using this novel device in order to study the hydrodynamics and the influence geometric and operating factors have on the minimum spouting velocity in fountain confined conical spouted beds, with and without draft tubes. The beds are made up of fine sand and sawdust particles. Based on an experimental design, it was ascertained that, although certain factors are influential in given configurations, those of greater influence in all the configurations are the solid properties, static bed height and gas inlet diameter. Therefore, new correlations have been proposed for predicting the minimum spouting velocity in each configuration.