Liquid dispersion in large diameter bubble columns, with and without internals

Abstract

Liquid mixing has been studied in a 1 m diameter bubble column, with and without internals (vertical cooling tubes). The presence of internals significantly affects both large scale recirculation and local dispersion. The most common approach to model liquid mixing is the one-dimensional axial dispersion model, validated many times in small bubble columns without internals. This paper shows that this model is still appropriate to large columns, but without internals. A two-dimensional model, taking into account a radially dependent axial velocity profile, and both axial and radial dispersion, is required to account for the internals on liquid mixing.