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Título: A fundamental flotation model and flotation column scale-up /
Autores: Dobby, G. S. (Glenn Stephen), 1952-
Fecha: 1984
Publicador: McGill University - MCGILL
Fuente:
Tipo: Electronic Thesis or Dissertation
Tema: Flotation -- Mathematical models.
Separation (Technology) -- Mathematical models.
Descripción: A comprehensive model of particle collection in flotation is developed from a rigorous analysis of the relative motion between a particle and a bubble prior to and during particle-bubble contact. Collection efficiency E(,K) is derived as a product of collision efficiency E(,C) and attachment efficiency E(,A). From trajectory calculations E(,C) is correlated to the bubble Reynolds number and the Stokes number, a dimensionless inertia term. E(,A) is calculated as the fraction of particles which reside on the bubble for a time greater than the induction time. As a result of the velocity gradient are the bubble surface E(,A) decreases with increasing particle size. The model explains the peak in size-by-size recovery data that is often observed at intermediate particle sizes. The peak location is shown to shift to smaller sizes as induction time increases.
A scale-up model for flotation columns is also developed. The model uses measured values of collection rate constants and an experimental correlation of plant column mixing parameters to calculate collection zone recovery R(,K). R(,K) is interfaced with a variable cleaning zone recovery to yield a grade-recovery relationship for the plant column. The onset of bubble loading is accounted for.
Idioma: en