Exact and Approximate Expressions for Bubble–Particle Collision

✍ Scribed by Theodore J Heindel; Frederick Bloom

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 163 KB
• Volume: 213
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1999.6112

✦ Synopsis

The flotation microprocess of collision is investigated and an exact expression for the probability of collision (P c ) is developed based on the intermediate flow of Yoon and Luttrell (1). This expression for P c only assumes that the bubble and particle are spherical and that the particle radius is less than the bubble radius (i.e., R p < R B ). In addition to removing the requirement that R p Ӷ R B , the influence of a particle settling velocity is also included in the model development. The expression for P c is shown to be a function of three dimensionless groups: (i) the magnitude of the dimensionless particle settling velocity, ͦGͦ; (ii) the bubble Reynolds number, Re B ; and (iii) the ratio of particle to bubble radius, R p /R B .

The probability of collision model is compared to available experimental data and good agreement is shown. A parametric study is also completed for 0 < ͦGͦ < 1, 0 < Re B < 500, and 0.001 < R p /R B < 1. In general, P c is independent of Re B when R p /R B Շ 0.03, the particle settling velocity is important for small values of R p /R B , and R p /R B dominates as R p /R B 3 1.