Bubble formation and dynamics in gas–liquid–solid fluidization—A review

Current worldwide commercial activities in converting natural gas to fuels and chemicals, or gas-to-liquids technology use slurry bubble column reactors with column sizes considerable larger than those currently in practice. Such commercial activities have prompted further fundamental research interest in fluid and bubble dynamics, transport phenomena and the scale up effects of three-phase fluidization systems. The fundamental behavior of particular relevance to these activities is associated with the elevated temperature and pressure conditions.This review attempts to summarize the salient characteristics of liquid, bubbles, and particles and their interactive behavior and dynamics in the process of bubble formation and bubble rising in gas–liquid–solid fluidization systems. Measurement techniques including both intrusive techniques such as the probes, and non-intrusive techniques such as tomography, that are used to study fluid and bubble properties in gas–liquid and gas–liquid–solid systems, are illustrated. Governing mechanisms of bubble–particle collision and bubble breakup are discussed. The state-of-the-art computational techniques, that consider both the discrete and the continuum approaches for movement of the particle and bubble phases along with the discrete simulation results, are presented. Of particular emphasis is the effect of pressure and temperature on the fluid and bubble dynamics in three-phase fluidization.