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Download or read book Hydrodynamics Study of the Bubble Columns with Intense Vertical Heat-exchanging Tubes Using Gamma-ray Computed Tomography and Radioactive Particle Tracking Techniques written by Abbas Jawad Sultan and published by . This book was released on 2018 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Understanding the hydrodynamics of bubble columns with and without vertical heat-exchanging tubes is a necessity for the proper design, scale-up, and operation of these reactors. To achieve this goal, systematic experiments were performed to visualize and quantify the influence of the presence of vertical internal tubes on the gas holdup distributions and their profiles, axial liquid velocity, and turbulent parameters (i.e., normal and shear stresses; turbulent kinetic energy) by using advanced gamma-ray computed tomography (CT) and radioactive particle tracking (RPT). In this study, the experiments were conducted in 6- and 18-inch bubble columns with an air-water system as the working fluid, under a wide range of superficial gas velocities (5-45 cm/s). Three configurations of vertical internals (i.e., hexagonal, circular without a central tube, and circular with a central tube plus vertical internals), as well as the vertical internals sizes, were examined in this study. These three configurations were designed to cover 25% of the column's cross-sectional area (CSA) to represent the percentage of the covered area utilized in the Fischer-Tropsch process. Reconstructed CT images reveal that the configurations of the vertical internal tubes significantly impacted the gas holdup distribution over the CSA of the column. Additionally, the bubble column equipped with 1-inch vertical internals exhibited a more uniform gas holdup distribution than the column with 0.5-inch internals. Moreover, a remarkable increase in the gas holdup values at the wall region was achieved in the churn turbulent flow regime due to the insertion of vertical internals inside the column. Furthermore, pronounced peaks of the gas holdup and axial liquid velocity were observed in the inner gaps between the vertical internals"--Abstract, page iv.