Hydrodynamics of TBC with non-Newtonian liquids: Liquid holdup

An experimental study was conducted to investigate the hydrodynamic characteristics of a turbulent bed contractor (TBC) with non-Newtonian liquids under different operating conditions. Hollow plastic spheres fluidized in an air stream countercurrently with an aqueous solution of carboxy methyl cellulose (CMC) of an apparent viscosity ranging from 5 to 25 mPa s. The first set of experiments confirmed the non-Newtonian behavior of the CMC solutions and experimental data were fit to power law model. The second set of experiments was conducted to analyze the hydrodynamic behavior of CMC solutions in the turbulent bed contractor. The existence of three hydrodynamic stages was characterized and the analysis was confined to the fully fluidized bed regime. The column was operated at different superficial gas velocities, liquid flow rates, static bed heights and CMC solutions concentrations. udy concluded that the liquid holdup rises with solutions of higher CMC content, which are more viscous for different liquid flow rates. But less liquid holdup is observed with higher static bed heights irrespectively of the solution viscosity. This study presents a new insight on the behavior of the non-Newtonian liquids in TBC beds.