X-ray computed tomography in large bubble columns

A noninvasive X-ray technique for determination of liquid holdup in a rotating packed bed

“…Thus, novel methods that can identify internal flow features and accurately give information on hydrodynamics without disturbing the flow field have obvious advantage. X-ray Computed Tomography (CT) is one of the noninvasive techniques that can be used to analyze internal objects and their characteristics under a given multiphase flow operation (Hubers et al, 2005). In fact, industrial processes involving opaque phases which cannot allow the use of optical techniques for measurement of flow parameters were found tomography and its other various forms as the only way to obtain the required information (Chaouki et al, 1997).…”

Applications of tomography in bubble column and trickle bed reactors

“…CT techniques have been used to characterize changes in the flow structure from different sparger designs (Ong et al, 2009;Varma & Al-dahhan, 2007), internals (Chen, Kemoun, et al, 1999;Chen, Li, et al, 1999) and composition (Hubers et al, 2005;Patel & Thorat, 2008) and have also been explored as a means to characterize the flow regime using ideas from chaos analysis (Nedeltchev, 2009;Nedeltchev et al, 2006Nedeltchev et al, , 2007. However, these studies have been limited to time-averaged measurements owing to the long time taken to acquire conventional CT measurements.…”

“…A variety of techniques have been used to characterize the hold-up including electrical capacitance tomography (ECT) (Bennett, West, Luke, Jia, & Williams, 1999;Cai, Shen, Shen, & Dai, 2010;Warsito & Fan, 2001Warsito, Ohkawa, Kawata, & Uchida, 1999), electrical resistance tomography Ishkintana & Bennington, 2010;Toye et al, 2005;Vijayan, Schlaberg, & Wang, 2007), ultrasonic tomography (Supardan, Masuda, Maezawa, & Uchida, 2007;Utomo, Warsito, Sakai, & Uchida, 2001;Warsito et al, 1999), X-ray or g-ray computed tomography (CT) (Chen et al, 1998;Fischer & Hampel, 2010;Gulati, Behling, Munshi, Luke, & Mewes, 2010;Hubers, Striegel, Heindel, Gray, & Jensen, 2005;Nedeltchev, Shaikh, & Al-Dahhan, Figure 18.1 Schematic diagram illustrating a bubble column reactor. Gas enters the column through a gas distributor or sparger in the base of the column.…”

Image analysis of X-ray tomograms of sludge during convective drying in a pilot-scale fixed bed

“…The 420 kV source allows investigation of highly absorbing materials, such as thin metallic objects, and was used to study the structure of a packed bed during drying with a resolution of 0.36 mm. Three other research groups developed largescale X-ray CT systems for chemical engineering applications, namely those of R. B. Eldridge at the University of Texas at Austin (Schmit et al, 2001, D. Mewes at the Leibniz University of Hannover (Mahr and Mewes, 2007;Gulati et al, 2010;Athe et al, 2013), and T. Heindel at the Iowa State University (Hubers et al, 2005;Ford et al, 2008;Franka and Heindel, 2009).…”