Study on flow characteristics and phase holdup in a slurry bubble column coupled with mild agitation

Abstract

A pilot-scale experimental setup was constructed to investigate the effect of mild agitation on the bubble characteristics and phase holdup in a slurry bubble column. Mild agitation positively impacts the axial uniform distribution of solid holdup, though it shows insignificant influence on the radial distribution. In homogenous regime, mild agitation promotes the coalescence of bubbles, and the effect becomes stronger with increasing agitator speed. The mild agitation contributes to a decrease in bubble size in heterogeneous flow regime. Mild agitation presents a significant effect on the gas holdup by adjusting the bubble size and bubble motion trajectory. The modification was introduced to predict the gas holdup considering the effects of mild agitation, a necessary consideration for applications requiring mild agitation. This adapted model predicts gas holdup with a maximum error of 12.9%.