(473d) CFD DEM Coupling Validation for Pneumatic Separation of Sugarcane Bagasse

The sugarcane bagasse is a byproduct generated at sugarcane mills after the sugarcane juice extraction. This biomass is characterized as a heterogeneous material both in cellular composition as particlesâ?? sizes. Aiming to separate this biomass in more homogenous particles groups were performed some tests of pneumatic classification in pilot scale equipment. Some studies submitting fine classified particles at moisture equilibrium to enzymatic hydrolysis showed the cellulose to glucose conversion without any extra pretreatment presented good results. One of the main bottlenecks to second generation ethanol be feasible from biomasses as bagasse is precisely related to hydrolysis costs. Thus, the pneumatic classification can avoid energy consumption in physical pretreatments used to reduce bagasse particle before the hydrolysis process as milling, gridding or a combination of these and consequently reduce process costs. Inspired by previous findings the scope of this study was to understand the behavior of bagasse when it was separated in a fluidized bed. Thereunto were realized computation simulations using ANSYS FLUENT and ROCKY software that modeled the separationsâ?? experiments based on computation fluid dynamics (CFD) and discrete element method (DEM). The simulations allowed the separation analysis of different air velocities showing when the air velocity was enough to separate intermediate group of particles the contacts particle/particle and particle/wall was higher than when used high velocities, thus the separation was more efficient when the objective was to separate the coarsest particles. It was concluded this first model adopted was well satisfactory to predict a real separation of sugarcane bagasse.