Influence of Liquid Viscosity and Solid Load in a Three-Phase Bubble Column using Stereoscopic Particle Image Velocimetry (Stereo-PIV)

Abstract

The bubble motion in non-Newtonian fluids is extensively used in many industrial processes. The influence of the liquid viscosity in the hydrodynamic behaviour of bubble columns is related to the bubble formation processes and the tendency to coalescence. In addition, the solids distribution through the column affects the system characteristics. The objective of this study is to evaluate the effect of the liquid properties and the influence of the solid phase on the bubble column hydrodynamic characteristics for a three-phase system. The experimental studies were carried out in a cylindrical bubble column laboratory scale with 145 mm internal diameter and a height of 1m. The three-phase system is consisted as follows: air as gas phase, solution of Carboxymethyl Cellulose (CMC) with liquid phase weight percentage of 0.25 wt%, and FCC particles with particle diameter of 100-125 µm. The air was injected at the bottom of the column using a gas sparger with 21 holes of 1mm diameter each, disposed in the central region of the column. For all the experiments were used an initial liquid height of 0.8 m and gas flow rate of 1.5 L/min. The effect of the viscosity and solid load under mean liquid velocity was measured using a non-intrusive technique Stereo Particle Image Velocimetry (Stereo-PIV) with Rhodamine B as a tracer particle. The results for a non-Newtonian solution (CMC) and solid load are presented and discussed.