Hydrodynamics and mass transfer characteristics of co-current downflow packed tube columns

Abstract

Hydrodynamics and effective interfacial area in a 25 mm i.d. packed tube column were studied over a wide range of operating conditions for demister pad packings (DPP). Flow maps have been prepared. Values of effective interfacial area as high as 1880 m^-1 in the spray flow regime were obtained. Data on pressure drop and effective interfacial area have been correlated for different flow regimes. Values of liquid side volumetric mass transfer coefficient, k_La, were measured by absorption and desorption of oxygen in different packed tube columns containing Pall rings (standard and low height to dia. ratio), multifilament wire gauge packings (MFWGP) and DPP. kL a was found to vary from 0.017 to 0.34 s^-1 for DPP. Values of wall side solid-liquid mass transfer coefficient, k_SL, were obtained in a 25 mm i.d. copper tube column packed with MFWGP by the dissolution of copper in acidic dichromate solutions. Values of wall side heat transfer coefficient could be obtained by analogy.