Molybdenum ore flotation process and equipment

Molybdenum, with its excellent physical properties - high melting point, boiling point, hardness and density, and as an excellent conductor of electricity and heat, is widely used in the production of alloy additives, stainless steel, tool steel and temperature-resistant steel. Due to the naturally good floatability of molybdenum ores, especially molybdenite, flotation has become the preferred treatment technology. With the continuous advancement of mining technology, flotation technology and related equipment are also constantly innovating to adapt to larger-scale mineral processing needs.

1. Flotation process of molybdenite

Molybdenite has good flotation properties due to its unique layered structure. In the flotation process, hydrocarbon oils such as kerosene and diesel are usually used as collectors, and pine alcohol oil is used as a foaming agent. It is worth noting that the concentrate can be successfully flotated even when only foaming agent is used.

However, the softness of molybdenite causes it to easily adhere to other mineral particles during grinding, causing over-crushing. However, due to its excellent floatability, even larger particles can float smoothly as long as a small amount of molybdenite is exposed on the particle surface. This can result in gangue minerals being mixed into the concentrate, thereby reducing its quality. Therefore, most molybdenum ore beneficiation processes use rough grinding and rough selection, and then the coarse concentrate is returned to the grinding system for reprocessing to achieve more complete mineral dissociation and then refining. This strategy of graded grinding and graded beneficiation helps to improve the quality of the concentrate.

2. Overview of molybdenum ore flotation equipment

Flotation equipment can be roughly divided into mechanical flotation equipment, flotation columns and reactor/separator flotation equipment according to their working principles. Among them, mechanical flotation equipment is named after its internal agitator, while flotation columns do not rely on mechanical agitation.

Application of mechanical stirring flotation machine

This type of flotation machine can be divided into two types: self-priming type and inflatable type according to different inflation methods. The self-priming flotation machine relies on the rotation of the impeller to generate negative pressure, sucking in air and mixing it with the slurry. Inflatable flotation machines, on the other hand, rely on external fans to inject air. In contrast, the self-priming flotation machine may be slightly insufficient in aeration, resulting in slightly lower flotation efficiency.

Applications and advantages of flotation columns

The basic structure of a flotation column includes a cylinder and a cone, both of which are equipped with an inflator at the connection. The slurry is fed from the top, while air enters the aerator through the annular air chamber and the aeration duct, and the subsequently formed bubbles are evenly dispersed throughout the slurry. In this process, the particles collide with the bubbles and stick together, then rise to the surface of the liquid to form a foam layer, and are eventually scraped out or overflowed, thereby obtaining a hydrophobic concentrate.

The flotation column is characterized by its easily controllable foam layer thickness, bubble size and number. In addition, its operation is mainly achieved by adjusting the air volume, so the air volume has a significant impact on its working effect. As a key component of the flotation column, the aerator's performance directly affects the aeration effect, bubble dispersion degree and flotation efficiency.

Compared with traditional flotation machines, flotation columns are simpler in technology and have obvious advantages for sorting fine or particulate molybdenum ores. In addition, the flotation column is easier to realize automatic control, making it more competitive in modern molybdenum ore beneficiation. At present, although mechanical stirring flotation machines still dominate molybdenum ore beneficiation, flotation columns have been successfully used in some large-scale mineral processing plants and have achieved satisfactory technical and economic results. Especially in the beneficiation stage, the application of flotation columns can effectively improve the grade and metal recovery rate of molybdenum concentrate.