Froth Flotation Process for Mineral Separation

Objective of the Flotation Process

The objective of the flotation line is a physicochemical process that allows the separation of sulfide minerals, such as copper sulfide and molybdenum minerals, from other species that share most of the original mineral. Flotation is performed using the pulp from the grinding stage, which has already incorporated the necessary reagents. The pulp is placed in containers called flotation cells, in which air bubbles are introduced while keeping the mixture under constant agitation so that particle contact is intense.

Concentration Cycles and Final Product

To obtain the product of the phase that requires flotation, the pulp passes through several cycles where bubbles generate a concentrate. For example, copper concentrate increases from values of 1% of the original rock up to 31% of total copper. The final concentrate is dried using appropriate equipment and taken to the smelting process.

Description of the Flotation Process

Flotation is a process of concentration that involves the selective separation of mineral species according to hydrophobization properties. In order to appreciate froth flotation as a system of chemical reactions and also as a metallurgical technique, it is essential to understand why this process is practiced.

Froth Flotation as a Treatment Method

Froth flotation serves as a means of treating pulp and minerals so that solids obtain a desired value in a concentration that is easy to handle for further processing. Under favorable conditions, these coated particles bind chemically to the air bubbling through the pulp and thus float to the surface.

Conventional Flotation Parameters

Froth flotation, also known as conventional flotation, operates with a granulometry between 0.3 to 0.002 mm, depending on the specific gravity of the species and its degree of liberation.

Types of Flotation Separation

• Collective Flotation: Separation occurs where several components are divided into two groups, of which the concentrate contains at least two or more components.
• Selective or Differential Flotation: Separation is made of composites where the product contains no more than individual species.

Technology and Flotation Operation

The technology consists of hydrophobic particles selectively separating from the hydrophilic ones; this is done in tuned machines. One of the most important components in flotation is the reactants.

Role of Collectors in Mineral Flotation

Collectors are organic compounds whose role is to hydrophobize useful particles; they absorb onto the surface of the particle selectively. The action of the collector is the subject of great research, more than any other phase of the process; however, the actual mechanism of collector adhesion remains a polemic.