Patent ID: 8196750

Claim:
A method of concentrating algal particles in a liquid-particle dispersion feed by adsorptive bubble separation, the method comprising: intimately contacting a gas with a pressurized stream of liquid in a chamber to form an aerated dispersion that retains at least some kinetic energy from the pressurized stream; removing at least some of the kinetic energy from the aerated dispersion to form a dense foam; introducing the liquid-particle dispersion feed into the dense foam, after the dense foam is formed, to form a gas-liquid-particle dispersion and thereby preserve any flocculated particles or agglomerates in the liquid-particle dispersion feed; introducing the gas-liquid-particle dispersion into a flotation chamber at a point below a surface of a liquid concentrated therein, wherein the gas-liquid-particle dispersion in the flotation chamber forms bubbles comprising a gas-particle agglomerate, and wherein the bubbles rise to the surface of the liquid in the flotation chamber to form a floating froth enriched in the particles; collecting the froth in a froth collection launder; and spraying collapsed froth liquid into the froth collection launder to drive persistent froth into the launder.