Spatial distribution of gas and solid phases in conical slurry bubble columns

S. Siquier, A. Ronchett, M. Calderón, P. Llaguno, Avelino E Saez

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In this work we perform an experimental study of the spatial distribution of phases in slurry bubble columns with conical distributors that have a volume comparable to that of the cylindrical section. Three different distributors were used whose apex angles were 13°, 22° and 34°. In gas-liquid operation, the gas holdups are axially uniform in the cylindrical section and decrease towards the wall, whereas in the conical section they increase towards the inlet. These trends are observed in the three cones for all the operating conditions explored. The solids distributions in the conical sections are qualitatively different depending on whether the operation is semibatch or continuous with respect to the flow of solid liquid suspension: in semibatch operation, the concentration monotonically increases towards the bottom of the cone and exhibits a slight increase as the wall is approached; in continuous operation, an absolute maximum in solids concentration is obtained at a point located on the wall of the cone and intermediate height. The location of this maximum moves upwards as the total solids content in the column increases and as the apex angle decreases. The maximum in solids concentration signals the most probable site for the onset of solids sedimentation and the presence of low mixing levels and reduced mass transfer rates in a slurry reactor. In the range of conditions explored in the present work, the lowest apex angle (13°) yields a more uniform solids distribution throughout the system.

Original languageEnglish (US)
Pages (from-to)173-190
Number of pages18
JournalChemical Engineering Communications
Volume159
StatePublished - 1997
Externally publishedYes

Fingerprint

Bubble columns
Spatial distribution
Gases
Cones
Flow of solids
Liquids
Sedimentation
Suspensions
Mass transfer

Keywords

  • Bubble column
  • Conical distributor
  • Sedimentation-dispersion
  • Tapered column

ASJC Scopus subject areas

  • Chemical Engineering(all)

Cite this

Spatial distribution of gas and solid phases in conical slurry bubble columns. / Siquier, S.; Ronchett, A.; Calderón, M.; Llaguno, P.; Saez, Avelino E.

In: Chemical Engineering Communications, Vol. 159, 1997, p. 173-190.

Research output: Contribution to journalArticle

Siquier, S, Ronchett, A, Calderón, M, Llaguno, P & Saez, AE 1997, 'Spatial distribution of gas and solid phases in conical slurry bubble columns', Chemical Engineering Communications, vol. 159, pp. 173-190.
Siquier, S. ; Ronchett, A. ; Calderón, M. ; Llaguno, P. ; Saez, Avelino E. / Spatial distribution of gas and solid phases in conical slurry bubble columns. In: Chemical Engineering Communications. 1997 ; Vol. 159. pp. 173-190.
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