Hydrodynamic Characterization and Mass Transfer Analysis of an In-Line Multi-Jets Ozone Contactor

Abstract

This research study investigates mixing and ozone mass transfer characteristics of a pilot-scale in-line multi-jets ozone contacting system. The hydrodynamic characteristics of the contactor were studied using a two-dimensional laser flow map particle image velocimetry coupled with planar laser induced fluorescence (PIV/PLIF). The PIV/PLIF system provided a combination of simultaneous whole-field velocity and concentration data in two-phase flows for different operating conditions. All measurements were conducted under a total liquid flow rate of about 10 L/s with gas flow rate ranging from 0.05 to 0.4 L/s. The gas was introduced to the system through a series of side stream injectors. The side injectors were tested under opposing and alternating modes. A mass transfer study was also conducted to estimate the overall mass transfer coefficient under the same operational conditions used for the hydrodynamics study. It was found that for the same number of jets (i.e., same gas flow rate) the liquid dispersion (DL) was higher when alternating jets were used. Higher ozone mass transfer rates were observed when using opposing jet compared to the same number of alternating jets.