Trickle flow distribution and stability by X-ray radiography

Liquid flow texture analysis in trickle bed reactors using high-resolution gamma ray tomography

“…For that reason, a proper pre-wetting procedure was realized in order to guarantee stable flow patterns for a longer period of time. It was shown by van der Merwe et al [26] that trickle flow is stable in all but the Levec pre-wetting mode for porous alumina catalyst particles. Additionally, their radiographic images indicated that the liquid saturation stabilizes shortly after the end of the start-up procedure for all prewetted beds.…”

Three-dimensional analysis of trickle flow hydrodynamics: Computed tomography image acquisition and processing

“…This data acquisition frequency therefore is 0.38 images/s, meaning that each radiograph takes 2.6 s to acquire (1.5 s exposure time and 1.1 s to rotate 1 • ). The source-object distance is 610 mm, allowing geometric enlargement of the sample (see Van der Merwe et al, 2007). A height of 61 mm of the bed located 539 mm from the top of the bed was imaged.…”

“…However, a comprehensive investigation into the local stability of trickle flow based on consecutively acquired radiographs showed that apart from low frequency and small (particle scale) instabilities in one of the pre-wetting modes, the trickle flow pattern is stable ( Van der Merwe et al, 2007). This means that the dynamic error in the reconstructed images is small and that the patterns observed are stable flow configurations.…”

Applications of tomography in bubble column and trickle bed reactors

“…CT techniques have also been used to explore the distribution of liquid at the entrance of packed bed columns and catalytic beds (see e.g. Bazer-Bachi et al, 2013;Fourati, Roig, & Raynal, 2012;Kalaga et al, 2009;Merwe, Nicol, & Beer, 2007;Roy et al, 2005 and references therein). For example, Figure 18.8 illustrates the distribution of liquid in a trickle bed reactor of diameter 0.6 m with two types of distributors: a chimney tray with deflectors and a gas-lift distributor.…”