investigation on liquid-liquid dispersion in stirred tanks through experimental approach and computational fluid dynamic (cfd)
abstract
stirred tanks have a vital role in chemical engineering industries. among the various
applications of stirred tanks, mixing of two immiscible liquid phases is of interest in chemical
processes. mixing of two immiscible liquids in the stirred tank is an integral part of achieving
a stable emulsion, which impacts the product quality. the design of the stirred tanks including
but not limited to the geometry and dimensions of the vessel, the location, size, and the type
of the impeller, fluid rheology, and the volume fraction of dispersed phase relies on
comprehensive knowledge about the liquid-liquid mixing performance. one of the major
factors affecting the stability of liquid-liquid dispersion is droplet size distribution (dsd) of
dispersed phase. the study of dsd in liquid-liquid dispersions still relies on experimental
data.
the main objective of this study is to evaluate the effect of dispersed phase viscosity, volume
fraction, and agitation speed on dilute liquid-liquid dispersions. therefore, the liquid-liquid
dispersion in stirred tank has been evaluated through electrical resistance tomography (ert),
focused beam reflectance measurement (fbrm), and computational fluid dynamics (cfd).
ert provides a non-intrusive online measurement to evaluate the mixing hydrodynamic of
dispersion in the tank. fbrm technique is an online particle size measurement technique
which evaluates the effect of mixing process on particle interactions and droplet size
distribution. using cfd coupled with population balance modeling (pbm) is the last step
toward complete analysis of liquid-liquid dispersion process.