After the reduction of the mineral by the process of crushing and grinding, it is passed to the processes of hydrometallurgy and pyrometallurgy, there are several concentration processes, one of which is the flotation.
This process uses a chemical treatment of the mineral to create favorable conditions for the adhesion of certain mineral particles to air bubbles, having as objective the separation of several species of minerals in an aqueous solution, and is based on the properties of affinity or repulsion to water.
In most cases the majority of the solution is composed of hydrophilic minerals which causes these particles to remain in suspension and sink, the hydrophobic minerals instead separate from the solution and adhere to the bubbles, usually hydrophobic minerals are also aerofilic, that is, they have affinity with air.
For the correct separation of these two types of minerals, different reagents are added to enhance their hydrolytic and hydrophobic characteristics and air is passed through the solution generating bubbles where the target mineral adheres.
This foam, now called concentrate or pulp, is collected from the flotation cell and sent to other processes such as drying and smelting and the part of the solution that does not float with the bubbles is sent to another cell to increase the probability of recovery, once the minerals have been recover, this solution or tail is sent to ponds also known as tailings dams.