Flotation is a method of wet separation of grinded solid minerals according to the different physical and chemical properties of mineral surface. The flotation method commonly used in industry is essentially froth flotation. It is characterized by the addition of chemical additives to the pulp and the introduction of air. After strong stirring, bubbles are generated and the related minerals are attached to the bubbles, thus achieving the separation effect. Although there are different types of flotation machine. But the effect is the same.
engineers things that the flotation process generally includes the following basic stages:
1. The ore should be grinded to a certain size before flotation. The purpose is to dissociate useful minerals and gangue monomers and to control particle size so as to make them suitable for flotation.
2. Preparing pulp. It includes adjusting pulp concentration, adding flotation reagents, adjusting pulp acidity and basicity, and eliminating harmful ions in flotation process. The surface properties of minerals should be changed to meet the requirements of mineral selection.
3. Air is introduced into the flotation machine to form a large number of bubbles. The ore particles adhered to the bubbles and floated with the bubbles to form a foam layer on the surface of the ore slurry.
4. Scraping out floating foam products to achieve the purpose of flotation.
Under normal circumstances, the foam product of flotation is produced as concentrate. But sometimes gangue minerals are floated into foam products while useful minerals are left in the pulp as the concentrate. This flotation process, which is contrary to normal flotation, is called reverse flotation.
There are two methods for flotation of polymetallic ores. One is to choose the useful minerals into foam products in turn, which is called preferential flotation. The other is to choose all the useful minerals into foam products at the same time, then separate the useful minerals from the mixed concentrate one by one, which is called mixed flotation.