Title: Two- and three-phase simulations of an ill-functioning dissolved-air flotation tank

Authors: Vasiliki A. Emmanouil; Thodoris D. Karapantsios; Kostas A. Matis

Addresses: Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Univ. Box 116, 541 24 Thessaloniki, Greece. ' Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Univ. Box 116, 541 24 Thessaloniki, Greece. ' Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Univ. Box 116, 541 24 Thessaloniki, Greece

Abstract: Computational Fluid Dynamics (CFD) simulations were employed to examine the performance of a large-scale Dissolved-Air Flotation (DAF) tank. The tank was ill-functioning as it was operated with bubbles larger than designed for. Different multiphase models, turbulence models and boundary conditions for the free surface of the tank were tested in 2D simulations. The simulation results were assessed through comparisons of the predicted spatial distributions of water velocity, volume fraction of air bubbles, solid particles and bubble/particles aggregates inside the tank. Comparisons revealed interesting similarities and differences between the examined models which were discussed as regards computational convenience and prediction goodness.

Keywords: CFD; computational fluid dynamics; DAF; dissolved-air flotation; flotation tanks; large bubbles; zeolites; turbulence modelling; multiphase models; simulation.

DOI: 10.1504/IJEWM.2011.042632

International Journal of Environment and Waste Management, 2011 Vol.8 No.3/4, pp.215 - 228

Received: 08 May 2021
Accepted: 12 May 2021

Published online: 23 Sep 2011 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article