In modeling flotation, the process of bubble-particle interaction is usuall
y divided into three subprocesses, including collision, adhesion and detach
ment. Of these, the hydrodynamics of bubble-particle collision has been stu
died most extensively by many investigators, and the results are useful for
the design and scale-up of flotation cells. The process of adhesion, on th
e other hand, is least understood because it is essentially controlled by t
he chemistry of the system, which is complex and difficult to model mathema
tically. However, it is possible to determine the probability of the bubble
-particle adhesion from the induction times that can be measured experiment
ally under different chemical environments. Furthermore, the new informatio
n reported in the literature on the hydrophobic forces of both particles an
d bubbles allow prediction of adhesion probabilities using various surface
chemistry parameters. Consideration of both the hydrodynamic and surface fo
rce parameters is essential in predicting flotation rates from first princi
ples. (C) 2000 Elsevier Science B.V. All rights reserved.