Title page for ETD etd-07132010-125302


Type of Document Dissertation
Author Do, Hyunsun
Author's Email Address doh@vt.edu
URN etd-07132010-125302
Title Development of a turbulent flotation model from first principles
Degree PhD
Department Engineering Science and Mechanics
Advisory Committee
Advisor Name Title
Roe-Hoan Yoon Committee Chair
Gerald luttrell Committee Member
Pavlos Vlachos Committee Member
Scott Hendricks Committee Member
Sunghwan Jung Committee Member
Keywords
  • flotation model
  • flotation
  • hydrophobic force
  • froth model
  • extended DLVO theory
  • foam
  • film rupture
  • drainage
Date of Defense 2010-06-08
Availability unrestricted
Abstract
Flotation is a process of separating particulate materials of different surface properties in a hydrodynamic environment, and is used extensively for separating different minerals from each other in the mining industry. In this process, air bubbles are introduced at the bottom of a particulate suspension (pulp), so that bubbles coated with hydrophobic particles rise to the top and form a froth phase while hydrophobic particles stay in suspension. The selectivity of the flotation process is determined by the hydrophobicity of the particulate materials involved, while the kinetics of the process is controlled by the hydrodynamic conditions and the disjoining pressures in the thin aqueous films between air bubbles and particles.

In the present work, a mathematical model for the flotation process has been developed by considering both the hydrodynamic and surface chemical parameters. The model can describe the events occurring in both the pulp and froth phases of a mechanically-agitated flotation cell. The pulp-phase model is based on predicting the kinetics of bubble-particle attachment using the DLVO extended to include contributions from hydrophobic force and the theory of turbulent collision. The froth-phase model is based on predicting the rate of bubble-particle detachment by considering bubble coarsening and water recovery. The predictions from the overall flotation model are in general agreement with the results obtained in single-bubble flotation experiments and the flotation test results reported in literature. Since the model has been developed largely from first principles, it has predictive and diagnostic capabilities.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Do_H_D_2010_v2.pdf 2.10 Mb 00:09:43 00:05:00 00:04:22 00:02:11 00:00:11

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.