Particle-to-bubble adhesion in gas/liquid/solid slurries

✍ Scribed by H. Vinke; P. J. Hamersma; J. M. H. Fortuin

• Publisher: American Institute of Chemical Engineers
• Year: 1991
• Tongue: English
• Weight: 689 KB
• Volume: 37
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690371205

✦ Synopsis

In gas/liquid/solid slurries, adhesion of small particles to gas bubbles is often encountered, for example, during flotation of finely divided minerals and in slurry reactors where particle-to-bubble adhesion may result in an enhanced gas absorption rate . The adhesion of smallparticles to gas bubbles in water isstudied with a modified bubblepick-up method. The extent of theparticleto-bubble adhesion is reuealed in the angle amaD by which the gas-bubble surface is covered by adhering particles under static conditions. It is shown that amu depends on the modified Eotvos number, the ratio of the particle and bubble radii, and the effective contact angle 0,. It is also found that 0, is affected by the curvature of the three-phase contact ring and by the type of the gas. A 'particle-to-bubble adhesion" model, indicated by PBA model, based on a balance of forces under static conditions, is developed to calculate the value of eE from the measured value,s of amax. The measured values of cos(8,) appeared to be a linear function of the curvature l / r of the three-phase contact ring which is in accordance with the extended Young-Dupre equation.