Composition of rare earth ores in China and beneficiation methods of rare earth ores

Introduction to the composition and beneficiation methods of rare earth ores in China

Rare earth metals, including trace (SC), y (Y) and La (LA) elements, 17 in total: SC, Y, la), Ce (CE), Pr, Nd (ND), medium (PM), Sm, Eu, Gd, and TB) dy, Ho, Er, Tm, Yb, and Lu ). It is light rare earth from LA to EU, and it is heavy rare earth from GD to Ti, which contains SC and Y. In the 18th century, only rare earth oxides like alkaline earth (such as calcium oxide) can be obtained, so they are named "Rare Earth" and are still in use. These metals have the same atomic structure, so their chemical properties are very similar. They are always associated in the ore. In the extraction process, they need to be extracted and separated by complicated operations.

Introduction to beneficiation methods of rare earth ore

A. Radiation Beneficiation Method

The difference between rare earth minerals in the ore and those in the vein stone minerals is mainly used. The gamma-ray radiation concentrator is used to separate the rare earth minerals from those in the vein stone minerals. Radiation beneficiation methods are mostly used for the selection of rare earth ore. Currently, this method is not widely used in industry.

 

　　B. Gravity Beneficiation Method

The density of rare earth minerals and gangue minerals is used for sorting. Common reselect equipments include cone separator, spiral separator, and shaker. The re-election is mainly used to separate rare earth minerals from those with low density Z and tungsten. This achieves the purpose of pre-selection and enrichment or rare earth concentrate. Reelection is widely used in the production of coastal sand ore. It is sometimes used as a means of pre-enrichment in the beneficiation of rare earth vein ore.

　　C. Magnetic Separation

Some rare earth minerals are weak magnetic. They can be used to separate rare earth minerals from other minerals by magnetic separator with different magnetic field strength, different from those of the associated gangue and other minerals. Weak Magnetic Separation is often used in the beneficiation of coastal sand ore to separate titanium from monjushi.

Strong Magnetic selection can also be used to separate the monjushi from zircon and Z minerals. In the beneficiation of rare earth pulse ore, in order to simplify the flotation process and save the flotation agent, strong magnetic beneficiation is sometimes used to pre-enrich rare earth minerals. With the continuous development of strong magnetic technology, strong magnetic will be more and more widely used in rare earth ore beneficiation process.

　　D. Flotation Method

The difference between the physical and chemical properties of rare earth minerals and companion minerals is used to separate the rare earth minerals from the companion gangue and other minerals to obtain the concentrate, it is the main beneficiation method widely used in rare earth pulse ore production. PAAs rare earth ore is produced by flotation. In the production of coastal sand ore, after heavy sand is obtained by reselection, the flotation method is often used to obtain rare earth Concentrate from heavy sand.

　　E. Electrical Selection

Rare earth minerals are non-good conductors, and their conductivity is different from those of associated minerals. They are separated by electric selection. Electric selection is often used in the selection of heavy sand ore in the coastal area.

　　F. Chemical beneficiation Method

For rare earth ores adsorbed on kaolin or clay as ions, the characteristics of rare earth ions soluble in sodium chloride or ammonium sulfate solution can be fully utilized, and the chemical Beneficiation Method first leaching and then precipitation can be used for recovery. Rare earth fluoride carbonate minerals that are easily soluble in acid or change phase at high temperature can be pre-enriched by flotation method, and then purified by Chemical beneficiation method (acid leaching or high temperature roasting.