1. Introduction
Three-phase bubble columns are extensively used in petrochemicals,
chemical and the processes of hydrogenation, chlorination, oxidation,
hydroformylation, bioremediation and cell growth [1–3] and also
play an significant role in all types of gas conversion processes, such as
direct or indirect coal to liquid processes, and Fischer–Tropsch synthesis
[4–6]. The flow behaviours of a gas–liquid–solid three-phase flow in
bubble columns are complex. Experimental technologies employed on
it are limited; various models have been adopted to describe the physical
phenomenon that occurs in bubble columns, and they involve
three types: the compartment models from chemical reactor engineering,
axial dispersion models and computational fluid dynamics (CFD)
models [7]. CFD tools have become more and more useful for exhibiting
flow features and predicting the flow pattern of bubble columns [8].
Many researchers focus on the CFD modelling gas–liquid bubble
columns [6–10]; however, very few researchers have studied the
interaction of gas–liquid–solid three-phases, and the simulation carried
out in an unsteady full 3D framework is very demanding [7]. It is
necessary to study the gas–liquid–solid flow of a bubble column,
which can give insight into the three-phase flow behaviours, the effect
of operation conditions and provide fundamental knowledge for industrial
processes