Hydrodynamics of secondary settling tanks and increasing their performance using baffles

Ali Tamayol, B. Firoozabadi, M. A. Ashjari

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

Generally, the flow in settling tanks is stratified, but the effect of buoyancy force on the flow field depends on the inlet concentration of particles and flow bulk velocity. A common approach for increasing settling tanks performance is to use baffles which can reduce effects of the unfavorable phenomena such as short circuiting between inlet and outlet and density currents in primary and secondary settling tanks, respectively. The suitable position of the baffles is related to the importance of buoyancy force. As a result, effects of inlet Reynolds and Froude numbers on the strength of buoyancy force are studied for a secondary settling tank and the results show that neither Reynolds nor Froude numbers are sufficient to be considered alone. Effect of buoyancy force on the suitable baffle position is also investigated. Results show that in high Reynolds numbers, the flow field and baffle position are not affected by the inlet Froude number.

Original languageEnglish (US)
Pages (from-to)32-39
Number of pages8
JournalJournal of Environmental Engineering
Volume136
Issue number1
DOIs
StatePublished - Jan 8 2010

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Settling tanks
Buoyancy
buoyancy
Froude number
Hydrodynamics
hydrodynamics
Reynolds number
flow field
Flow fields
density current
Current density
effect
settling tank

Keywords

  • Baffle configuration
  • CFD
  • Density currents
  • Secondary settling tank

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Civil and Structural Engineering
  • Environmental Science(all)

Cite this

Hydrodynamics of secondary settling tanks and increasing their performance using baffles. / Tamayol, Ali; Firoozabadi, B.; Ashjari, M. A.

In: Journal of Environmental Engineering, Vol. 136, No. 1, 08.01.2010, p. 32-39.

Research output: Contribution to journalArticle

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