Quantification of Gas Distribution and Void Fraction in Packed Bubble Column Using Electrical Resistance Tomography

Random or structured packing is typically used in the chemical reactors to increase the contact area between the gas and liquid phases, and thus improve reaction efficiency. Knowledge of how packing types and sizes affect the gas distribution and the overall gas void fraction is critical for the optimal design and operation of industrial processes. In this paper, a method of in situ quantifying the gas distribution and void fraction in a packed bubble column using electrical resistance tomography (ERT) is proposed. A 3-D simulation validation shows that the ERT is able to quantitatively determine the gas void fraction within 4% relative error against the theoretical value. The experiment was conducted in a bubble column, packed with 6-mm glass beads and 16-mm plastic pall rings. The results demonstrate that the gas distribution and the void fraction are considerably changed by different packing materials. All of these facts suggest that ERT is a reliable imaging tool for the real-time measurement of complex two-phase flows in the packed bubble column reactors.