Patent attributes
Process and apparatus are described for adsorptive bubble separation of hydrophobic particles from liquid dispersions. The process may be used to treat the gas/liquid dispersion after it has been introduced from two or more ducts near the perimeter or from a central duct of the separation vessel. When the gas-liquid-particle dispersion is introduced from a central duct, the rising bubbles are directed by, e.g., a baffle toward the perimeter of the apparatus, where they rise. At the liquid surface, bubbles with attached hydrophobic materials form a floating froth layer, which is directed toward a central froth collection launder. Rising froth at the perimeter pushing the froth bed into the reduced area of the center encourages further coalescence of the bubbles and increases liquid drainage from the froth, thus leading to concentration of the collected materials without the need for complex equipment geometry. Also disclosed is an improvement for froth flotation processes comprising using a vacuum to pull froth and/or collapsed froth into and through the froth collection launder and froth drain line. This improvement assists froth collection because froth can be pulled by suction through the collection system more easily than it can be drained by gravity.