Doctoral Dissertations

Keywords and Phrases

Axial Liquid Velocity; Bubble Column With Internals; Configurations Of The Vertical Internals; Gamma-Ray Computed Tomography (CT); Gas Holdup; Radioactive Particle Tracking (RPT)


"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.


Al-Dahhan, Muthanna H.

Committee Member(s)

Lee, Hyoung-Koo
Usman, Shoaib
Park, Joontaek
Rezaei, Fateme


Chemical and Biochemical Engineering

Degree Name

Ph. D. in Chemical Engineering


Higher Committee for Education Development in Iraq
Ministry of Higher Education and Scientific Research (Iraq)
Missouri University of Science and Technology


Missouri University of Science and Technology

Publication Date

Spring 2018

Journal article titles appearing in thesis/dissertation

  • Overcoming the gamma-ray computed tomography data processing pitfalls for bubble column equipped with vertical internal tubes
  • Influence of the size of heat-exchanging internals on the gas holdup distribution in a bubble column using gamma-ray computed tomography
  • Impact of heat-exchanging tube configurations on the gas holdup distribution in bubble columns using gamma-ray computed tomography
  • Investigating the influence of the configuration of the bundle of heat exchanging tubes and column size on the gas holdup distributions in bubble columns via gamma-ray computed tomography


xx, 277 pages

Note about bibliography

Includes bibliographic references.


© 2018 Abbas Jawad Sultan, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11321

Electronic OCLC #