Doctoral Dissertations

Keywords and Phrases

Bubble column reactor; CFD; Flow regime; Hydrodynamics; Multiphase flow


"Fischer-Tropsch synthesis (F-T) is a process utilized to convert the syngas mixture of CO and H2 to synthetic fuel and chemicals that executed commercially by using the bubble/slurry bubble column reactor. The experimental results reveal that the investigated parameters, in terms the presence of internals, and reducing the aspect ratio and the solids loading, increase the local gas holdup, interfacial area, bubble passage frequency, and decrease the bubble rise velocity, bubble chord length. Meanwhile, the aspect ratio H/D = 4, and 5 provide enough height to established the fully developed flow regime. As a result of the variation in the bubble properties that in turn reflected on the flow regime transition, therefore, the presence of internals and decreasing the aspect ratio delay the transition from the transition flow regime to churn turbulent flow regime. The validated CFD codes, using Eulerian-Eulerian approach incorporated with the population balance model PBM, exhibit the capability to simulate the bubble column in bubbly and turbulent flow regimes. However, results revealed that the presence of internals enhanced the gas holdup significantly in the wall region of the column. The gas holdup radial profiles in the presence of internals in different configurations provide a uniform gas holdup profile. While the results of the effect of internals diameter exhibit that the gas holdup was increased remarkably in the center and the wall regions of the bubble column equipped by internals of 1-inch diameter more than in using internals of 0.5-inch. However, the effect of internals configurations reported that the internals with hexagonal arrangement increases the gas holdup in the center region more than the circular arrangement, and less in the wall region comparing with the circular arrangement"--Abstract, page iv.


Al-Dahhan, Muthanna H.
Schlegel, Joshua P.

Committee Member(s)

Neogi, P. (Partho), 1951-
Smith, Joseph D.
Barua, Dipakr


Chemical and Biochemical Engineering

Degree Name

Ph. D. in Chemical Engineering


Higher Committee for Education Development in Iraq


Missouri University of Science and Technology

Publication Date

Spring 2019

Journal article titles appearing in thesis/dissertation

  • The effects of internals and low aspect ratio on the fully developed flow region and bubble properties in a pilot-plant bubble column
  • The impacts of solids loading and low aspect ratio on the bubble properties and fully developed region in a pilot-plant scale slurry bubble column with industrial heat exchanging internals for Fischer-Tropsch (F-T) synthesis
  • The impact of low aspect ratio on flow regime transition in industrial-sized pilot plant bubble column reactor
  • The effect of heat exchanging internals on the flow regime transition in industrial scale pilot plant bubble column reactor
  • 3D CFD simulation of bubble column reactor; Validation of interfacial forces and internals effect


xxii, 278 pages

Note about bibliography

Includes bibliographic references.


© 2019 Hayder Al-Naseri, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11516

Electronic OCLC #