A new correlation for the wall-to-fluid mass transfer in liquid–solid fluidized beds

Abstract

The mass transfer from a wall to a fluid in a liquid–solid fluidized bed has become of special interest with a novel cell culture bioreactor, aerated by a membrane module inside the reactor. This bioreactor has been used as an experimental setup for mass transfer experiments. A large set of data was generated, that includes a comprehensive variation of the main influencing parameters: bed porosity ( ε=0.4–1), particle diameter ( d p =0.325–3 mm) and density ( ρ p =2.5–11.343 kg/l), temperature (25–50°C) and fluid viscosity ( η l=9.08×10 -4–1.75×10 -2 Pa s). The range of the study covers a modified Reynolds number Re p /(1− ε) between 0.9 and 1652 and a Schmidt number between 151 and 7021 and therefore encompasses most of the variations studied by other authors. Based on these data, a new empirical correlation was developed, with major advances over the commonly used models. The new correlation predicts the mass transfer without the need of further correlation coefficients that has to be adapted to each experimental setup.