Effect of hydrodynamic and magnetic stabilization on fluidized-Bed adsorption.

Direct fermentation broth processing using fluidized beds is extremely advantageous due to the low operating pressure drop of the device and the ability of the bed to process suspended-solids-containing solutions. Unfortunately, the solid particles in fluidized beds typically show a great deal of mixing compared to those in packed beds. This mixing may lead to early breakthrough and inefficient use of adsorptive capacity. Stabilization reduces the solids mixing and improves the performance and efficiency of a fluidized bed. A comparison of packed, fluidized, and stabilized beds reveals that, while normal fluidized beds do contain a significant amount of mixing, the breakthrough 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 orientation. Permanently magnetized beds were also investigated and produced breakthrough efficiencies similar to those of packed beds.