Flotation is one of the most important methods for mineral separation. Because of its capability of fine particle processing, flotation has been applied to low-grade ores that other separation methods cannot handle economically. In flotation, ore is finely ground and is mixed with water to make a suspension called pulp. After the addition of flotation reagents such as a collector, frother, and so on, the pulp is subject to violent agitation with aeration in a flotation cell for sufficient collision between minerals and bubbles. The targeted minerals coated with hydrophobic collector film are captured at the air-water interface of bubbles and are lifted to the surface of the pulp to form a froth layer. The froth is skimmed off from the flotation cell as a concentrate, whereas unwanted minerals remaining in the pulp are discharged as tailing.