(283a) Advances in Packing Characterization Measurements

High performance packings are commonly used in absorption, stripping and distillation because of their relatively low cost, high turndown, low pressure drop and improved capacity.  Process engineers often rely on height of a transfer unit (HTU) or volumetric mass transfer coefficient (Ka) based models to design such columns.  The traditional approach utilizes film mass transfer coefficient models based on film theory along with a mass transfer area model based on back-calculations from Ka experimental data.  Therefore, neither the film mass transfer coefficient nor the mass transfer areas are measured directly. The designer must be careful to combine the proper film mass transfer coefficient model with its companion mass transfer area model. In physical mass transfer operations, errors in the predicted mass transfer area can be compensated for errors in the film mass transfer coefficients to provide a relatively accurate overall volumetric mass transfer coefficient.  However in reactive-based packed column operations, such as carbon dioxide absorption, accurate values of the mass transfer area are required.

The Separations Research Program has undertaken a significant study involving the consistent measurements of the mass transfer area and the film mass transfer coefficients for a wide variety of high performance packings.  An update in the SRP study will be provided in the presentation honoring Professor Bruce Eldridge.  Mass transfer area and film mass transfer coefficient data on a wide variety of structured and random packings will be provided.