Phases distribution in slurry bubble columns: Insights from single-source computed tomography and gas holdup measurements

Abstract

In this study, a cylindrical stainless-steel column with dimensions of 250 cm in height and 16.2 cm in diameter was employed to investigate how fluid properties influence phase distribution within slurry bubble columns. The research focused on various superficial gas velocities and operating pressures. Data collection was carried out using single-source Computed Tomography and overall gas holdup. The gas holdup was found to be directly proportional to both the superficial gas velocity and the operating pressure. Results revealed that both liquid properties and operating pressure have a considerable impact on flow regime transition. Interestingly, when comparing water to Therminol LT, higher gas holdup measurements were observed when water was used, displaying a relative difference of approximately 29% in the bubbly flow regime under ambient conditions. The effect of liquid properties on holdup profiles became more pronounced at high pressures. For example, under higher pressure conditions, Therminol LT exhibited a higher gas holdup rate due to its lower viscosity and surface tension, leading to an increased rate of bubble breakup. While the influence of physical properties on the solids' holdup profile was relatively less significant, it remained noteworthy when compared to its impact on the gas holdup profile.