Effect of hydrodynamic and magnetic stabilization on fluidized-bed adsorption

Direct fermentation broth processing using fluidized beds is extremely adva ntageous due to the low operating pressure drop of the device and the abili ty of the bed to process suspended-solids-containing solutions. Unfortunate ly, the solid particles in fluidized beds typically show a great deal of mi xing compared to those in packed beds. This mixing may lead to early breakt hrough and inefficient use of adsorptive capacity. Stabilization reduces th e solids mixing and improves the performance and efficiency of a fluidized bed. A comparison of packed, fluidized, and stabilized beds reveals that, w hile normal fluidized beds do contain a significant amount of mixing, the b reakthrough behavior of the bed is not drastically different than that of a packed bed. Magnetic stabilization of the bed usually leads to an increase in adsorption efficiency but is dependent on field strength and orientatio n. Permanently magnetized beds were also investigated and produced breakthr ough efficiencies similar to those of packed beds.