CFD-DEM simulations of a continuous square-based spouted bed and evaluation of the solids residence time distribution

CFD-DEM is an established approach to simulate spouted beds, but researchers usually focus on batch units, without commenting on the residence time distribution of the particles. In this work, we employed our validated CFD-DEM approach to simulate a continuously-fed square-based spouted bed, in the framework of the development of a scaled-up multiple unit. After analysing several flow patterns of the spouted bed, we propose three methods that permit evaluating the residence time distribution curve of the particles on the basis of the results of the simulations. These methods allow exploiting CFD-DEM's great reliability without reproducing the actual tracer experiment, which would be too time-consuming. Each method has advantages and disadvantages, but all of them were able to provide a good match of the experimental E(t) curve and may be applied to other devices as well.