Rare earth mineral processing methods

Rare earths are important raw materials needed for "high-precision" industries. Although there are more than 200 types of rare earth minerals, there are not many rare earth mineral resources with mining value. The main types are light rare earth ores and heavy rare earth minerals. There are three types of rare earths with mining value: bastnasite, monazite, and xenotime.

Rare earth beneficiation method of bastnaesite ore

Bastnasite can be divided into two types. One is a single bastnasite ore, which is a hydrothermal-filled vein deposit. Its main minerals are bastnasite, barite, calcite, silicate minerals and A small amount of sulfide ore; the other is a composite rare earth ore, which is a hydrothermal vein deposit.

This kind of rare earth ore is an easy-to-select ore, and there are few useful minerals in the mineral, and the main purpose is to recover bastnasite ore. For this type of rare earth ore, flotation is often used to complete the separation. During flotation, fatty acids are used as collectors to recover bastnaesite in weakly acidic ores.

Monazite rare earth mineral processing method

There are very few rare earth deposits of monazite. It is a terrestrial detritus, which is a difficult-to-weather mineral produced by rock weathering. It is washed and carried into the sea with the flow of large rivers, and then washed by seawater, washed repeatedly, and finally washed to the shore. Heavy sand formed over time. This type of rare earth ore contains a variety of useful minerals, such as statorite, thorite, tungsten ore, cassiterite, gold, rutile, etc., while monazite and xenotime are often recycled as by-products.

Due to its ore formation characteristics, monazite is more difficult to beneficiated. Generally, a combined process of flotation, electric separation, magnetic separation and gravity separation can be used to select qualified monazite concentrate. When monazite is beneficiated, the +10mm and -0.074mm particle sizes are generally thrown away by hydraulic classification, and the remaining heavy sand with a yield of about 10% is then purified through a combined separation process to obtain a concentrate product.

Mixed rare earth ore beneficiation method

Mixed rare earth deposits are often symbiotic with other elements such as iron and niobium. Due to the complex composition of this mineral deposit, the sorting performance, specific gravity, and conductivity of the main minerals such as magnetite, pseudomagnetite, hematite, bastnasite, and monazite, fluorite, and barite, The magnetic properties and floating properties are very similar, and the rare earth embedded particles are very fine (30% below 10 μm), making it more difficult to select.

Therefore, this type of ore deposit also uses a combined process to complete the separation, but the specific process plan needs to be determined according to the characteristics of the ore. For example, the Bayan Obo ore is a very large rare earth mine. After many years of research on this mine, the combined process used is a weak magnetic-strong magnetic-flotation process to recover iron and rare earths.