Analysis of Bubbles in a Fluidized Catalyst Bed using a Fast X-ray CT Scanner

A fast-scanning X-ray CT system was used to obtain the transient 2-dimensional cross sectional gas-phase distribution in a fluidized catalyst bed with fine particles. The captured data was sent to a PC for image reconstruction, and the density distributions across the horizontal cross-section were visualized. Using image-processing techniques, pseudo 3-dimensional images of bubbles and the density distribution across the vertical cross-section were obtained. The bubble structure was studied based on these images and the results obtained previously in a 2-dimensional fluidized bed. It was found that bubble shape was not spherical, but that the bubble ascending in a fluidized catalyst bed consisted of some smaller bubbles.