(647b) Validating Optimal Drag Corrections for the Simulation of Sand Biomass Co-Fluidization

The bubbling fluidized bed reactor is widely used in the fast pyrolysis of biomass to generate syngas and bio-oil. In this process, the biomass is co-fluidized with sands. Computational Fluid Dynamic (CFD) simulation of this reactor is challenging due to the large number of sand particles and lack of accurate drag corrections. In this research, the tracked number of sand particles is reduced by using the coarse grained discrete element method (CGDEM) where many sand particles are lumped into a numerical parcel. The drag corrections proposed by Gidaspow, Syamlal-O'Brien, and Ganser are evaluated using the experimental measured pressure drops at six different locations. Among all the tested four different superficial gas velocities and four biomass mass fractions, the Syamlal-O'Brien drag corrections shows superiority over others. The accuracy was also improved by using Syamlal-O'Brien drag corrections for sand parcels and using the non-spherical Ganser drag corrections for biomass particles.