Computational Fluid Dynamics Analysis of Ammonia (NH3) Selective Catalytic Reduction in Semicircular Ring-baffled Fluidized Bed Reactor

This study utilized an unsteady multiphase Computational Fluid Dynamics model in ANSYS FLUENT 2024 R2 to investigate the impact of semicircular baffles on the hydrodynamics and NOx removal efficiency in a fluidized bed reactor. Both standard and fast Selective Catalytic Reduction mechanisms were considered in the reactor employing the CuO/?-Al2O3 as catalyst. The baffle-free reactor (FFB) model was validated against experimental data through mesh optimization, and kinetic parameter calibration. Subsequently, systematic simulations of 27 baffled configurations (single, double, and triple baffles) demonstrated significant improvements in NO reduction. At 300 °C, configurations DB3, TB6, and TB14 generated the highest conversions of 93.20 %, 93.33 %, and 93.12 %, respectively. Notably, at 250 °C, these configurations maintained high efficiencies suggesting that the addition of baffles could replicate the performance of FFB even at a lower temperature. The study revealed that the semicircular baffles increased the solid holdup, radial gas velocity, and granular temperature, thereby enhancing gas–solid interactions.