Strategizing internals’ geometry to improve resilience of marinized bubbling fluidized beds to roll-induced maldistribution

Abstract

• Hydrodynamics of internally modified fluidized bed subject to roll motion. • Stimulation using a hexapod robot as a sea state simulator. • Analysis of gas/solid phases by PIV-DIA. • Geometric strategies improve resilience against gas maldistribution. Marinized bubbling fluidized beds show potential for reducing ship exhaust emissions, but their performance is hampered by the unstable marine environment, which affects their hydrodynamic stability. This study addresses the challenge of roll-induced maldistribution by testing different geometric strategies of bed internals to improve operational resilience. Direct visualization techniques (including digital image analysis and particle image velocimetry) were used to investigate the hydrodynamics and stability of bubbling fluidized beds under various configurations in pseudo-2D vertical, inclined, and rolling conditions. Internal designs, such as rhombic and herringbone patterns, and vertical baffle arrays, significantly shield the beds from gas maldistribution and provide stable fluidization comparable to conventional aboveground setups. The rhombic internals achieved up to 93% of the stability of classical vertical configurations without internals, while the herringbone reached 60 % and the vertical baffles reached 55 %. These configurations mitigate hydrodynamic fluctuations due to oscillations, improving operational reliability to effectively reduce emissions in marine environments.