Influence of Biomass Feed Position on Pyrolysis Performance in a Spouted Bed: A CFD Approach

Brazil is the world’s leading producer of sugarcane, and its bagasse constitutes a substantial biomass resource with a strong potential for renewable energy production via pyrolysis. The development of mathematical models capable of accurately representing pyrolysis phenomena is, therefore, essential for advancing process understanding and optimization. In this study, the influence of biomass particle injection location on pyrolysis conversion rates in a spouted bed reactor was investigated. A CFD Eulerian-Lagrangian model was developed and implemented in OpenFOAM. Model validation involved two preliminary steps: the simulation of single-particle pyrolysis to evaluate reaction kinetics and the simulation of the inert particle bed dynamics. Subsequently, three pyrolysis simulations were performed, varying the biomass injection point: the annular region, the fountain region, and the region above the fountain. Numerical results were validated against experimental data from the literature. Tar and gas production and particle temperature evolution were analyzed for each configuration, all exhibiting characteristic spouted bed behavior. The results demonstrated that biomass injection into the fountain region yielded the highest performance, resulting in a conversion rate of 54.65% and maximizing tar and gas production.