Paper Title
Computational Fluid Dynamics Modeling and Simulation of Circulating Fluidized Bed Coal Gasification

This article presents three dimensional full-loop Computational Fluid Dynamics (CFD) simulation of a circulating Fluidized Bed Gasifier (CFBG). Euler Granular Multiphase Model is utilized to describe the hydrodynamics of the gasifier. Eight heterogeneous and eight homogeneous reactions are used in the present model. After a grid independence study, the model is validated with experimental data. The simulation results agree well with the experimental data. The validated model is further utilized to study the effects of process parameters such as temperature, pressure, Air/Coal (A/C) ratio and Steam/Coal (S/C) ratio on the gasification performance. Pressure is observed to have little effect on the syngas composition at the outlet of the CFBG whereas temperature have a strong effect up to 1073 K then it levels off. The syngas composition shifts from combustion to gasification products with increase in S/C ratio as well as with decrease in A/C ratio. Methane concentration decreases with increase in both A/C and S/C ratios due to its participation in both combustion and gasification reactions. Keywords - Circulating Fluidized Bed, Computational Fluid Dynamics, Gasification, Full-Loop Simulation, Energy Minimization Multi-Scale Drag Model