[01] Md. Iqbal Hossain, Department of Chemical Engineering, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh. [02] Raymond Lau, School of Chemical and Biomedical Engineering, Nanyang Technological University, Jurong, Singapore. [03] Yanhui Yang, School of Chemical and Biomedical Engineering, Nanyang Technological University, Jurong, Singapore. [04] Armando Borgna, Division of Heterogeneous Catalysis, Institute of Chemical and Engineering Sciences, Jurong Island, Singapore.

The dynamic interactions between the gas and the liquid phases, irregularity in bubble shape, higher gas holdup, and high mechanical stress, etc at elevated pressures complicate the application of many techniques in bubble size measurement in bubble columns. In this study the feasibility of a new borescope-based imaging technique to determine the bubble size distribution in 3-dimensional bubble columns under elevated pressures is investigated assessing bubble size distribution over a range of superficial gas velocities and operating pressures. The observed size distribution results reveal that borescope-based imaging technique can be employed for the determination of bubble size distribution with reasonable accuracy in bubble columns under elevated pressures.

Bubble Size Distribution, Bubble Columns, Elevated Pressure, Borescope

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