Rare Earths

There are more than 200 kinds of minerals containing rare earth elements and their compounds. Among them, the industrial minerals with application value are mainly bastnaesite and monazite, followed by ion-adsorbed rare earth ore, gadolinite, loparite, thortveitite, etc.
According to statistics released by the US Bureau of Mines in 1985, the world ’s rare earth resources reserves totaled 45 million tons (REO). Among them, China has 36 million tons, accounting for 80% of the world’s total reserves; the United States has 4.9 million tons, accounting for 11%; India, 2.22 million tons, accounting for 5%; the former Soviet Union, 450,000 tons, accounting for 1%. The reserves of these four countries account for 97% of the world’s total reserves. The rest are mainly distributed in 14 countries in Asia, Africa, Europe, South America and Oceania.

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More Details at What’s Rare Earth Minerals – What are rare earths used for?

Gravity separation
Rare earth ore gravity separation process is based on the difference in density between rare earth minerals and gangue minerals. It is mainly aimed at the separation of rare earth minerals and gangue minerals such as quartz and calcite with low density. For example, the beach sand ore mostly uses the gravity separation method, or the beneficiation of the rare earth vein ore also uses the gravity separation as a pre-enrichment.

Flotation
Rare earth ore flotation process is one of the main methods of rare earth ore beneficiation It uses the difference in the physical and chemical properties of the surface of rare earth minerals and associated minerals to separate them from associated gangue and other minerals to obtain effective rare earth concentrates. For example, in Baotou Mine, the density and magnetic properties of fluorocarbon bowl ore and monazite are basically the same, so a flotation process is used. In addition, after gravity separation of seashore sand ore, the flotation method is often used to obtain rare earth concentrate from heavy sand.

Magnetic separation
Rare earth ore magnetic separation is a beneficiation method for some rare earth minerals or associated magnetite with weak magnetism. Different magnetic susceptibility coefficients of rare earth ore and associated gangue and other minerals are used, and magnetic separators with different magnetic field strengths are used for separation. For example, in the coastal sand ore, weak magnetic separation is used to separate its ilmenite from monazite, or strong magnetic separation is used to separate monazite from zircon, quartz and other minerals. In flotation rare earth ore, sometimes in order to simplify the flotation process and save flotation reagents, a strong magnetic separation process is also used to make the rare earth ore enrichment in advance.

Radiation beneficiation
The rare earth ore radiation ore dressing is to use the y-radiation machine to sort the rare earth ore and gangue minerals by using the different radon content in the rare earth ore and gangue species. The general radiation beneficiation method is mostly used for the pre-selection of rare earth ores.

Electrical selection

The method of electric separation of rare earth ore is mainly because the rare earth ore is a non-conducting conductor, so it can be used to separate it from the highly conductive mineral by taking advantage of its electrical conductivity and its associated mineral. Generally, the electric separation is mostly used for the selection of heavy sand after the reselection of seashore sand ore.