Solids Mixing in Marinized Bubbling Fluidized Beds: Gas Distribution Study

Marinized bubbling fluidized beds hold promise for reducing CO2, NOX, and SOX in ship exhaust gases, but their use at sea is hampered by a limited understanding of the influence of sea waves on hydrodynamics, heat transfer, and efficiency. To address this gap, this study used direct visualization techniques to investigate the solids mixing and hydrodynamics of bubbling fluidized beds under different gas distribution patterns in pseudo-2D vertical, inclined, and rolling beds. Digital Image Analysis (DIA) was used to determine the Lacey mixing index and the local void fraction, while Particle Image Velocimetry (PIV) was used to capture the particle velocity fields. Additionally, the effects of tilt angles and oscillation parameters of the nonvertical beds were compared with the conventional straight bubbling fluidized bed unit. The uniform inlet distribution of the fluidizing agent was compared with a variety of convex feed distributions at the bed entrance to correct for the negative effects of static/dynamic deviations from bed verticality necessary for optimal operation of bubbling fluidized bed reactors in marine environments.

Automated summary

Marinized bubbling fluidized beds are hindered in their use at sea due to a limited understanding of the influence of sea waves on their hydrodynamics, heat transfer, and efficiency. This study used direct visualization techniques to investigate the solids mixing and hydrodynamics of these beds under different gas distribution patterns. The effects of tilt angles and oscillation parameters were compared with conventional bed units, and different inlet distribution patterns were explored to optimize operation in marine environments.