Spodumene overview
The molecular formula of spodumene is LiAlSi2O6, the density is 3.03~3.22 g/cm3, the hardness is 6.5-7, non-magnetic, glassy luster, the theoretical grade of Li2O is 8.10%, and the spodumene is columnar, granular or plate-like. Monoclinic crystal system, its common colors are purple, gray-green, yellow and gray-white.Lithium is a light metal with special physical and chemical properties. It was mainly used in the military industry in the early days and was regarded as a strategic substance. At present, there are more than 100 kinds of lithium and its products. Lithium is mainly used in the production of high-capacity lithium batteries, additives in the electrolysis of aluminum, and low-temperature-resistant lubricants. In addition, the application in the fields of glass ceramics, electronic appliances, medicine and chemical industry is also becoming more and more extensive.
As a solid lithium mineral rich in lithium and most conducive to industrial production of lithium salts, spodumene is mainly distributed in Australia, Canada, Zimbabwe, Zaire, Brazil and China. The spodumene mines in Xinjiang Keketuohai, Ganzi and Aba in Sichuan, and the lepidolite mines in Yichun, Jiangxi are rich in lithium resources. They are currently the main areas for mining solid lithium minerals in China.
Spodumene concentrate grade
Spodumene concentrates are divided into different uses and grades. The standard for the grades of the concentrate output is shown in the table below. Concentrate output grades include the following three categories: low-iron lithium concentrate, lithium concentrate for ceramics and lithium concentrate for chemical industry.
Spodumene ore beneficiation method
The separation of spodumene is affected by many factors, such as: mineral symbiosis, ore structure type, etc., which requires different beneficiation processes.
Flotation：
Separating spodumene from silicate minerals with similar flotation performance is a difficulty in spodumene flotation methods at home and abroad. Spodumene flotation process can be divided into reverse flotation process and positive flotation process. The main lithium-containing minerals can be separated by flotation, especially for spodumene with low-grade, fine-grained, complex composition, flotation is very important.
Magnetic separation：
Magnetic separation is commonly used to remove iron-containing impurities in lithium concentrates or to separate weakly magnetic iron-lepidolite. In production practice, the spodumene concentrate obtained by flotation method sometimes contains more iron-containing impurities. To reduce the content of iron impurities, magnetic separation can be used for treatment. The magnetic separation equipment is a permanent-magnet drum-type magnetic separator, a wet-type strong magnetic plate-type magnetic separator, and a vertical ring high-gradient magnetic separator. The spodumene tailings are mainly composed of feldspar, and vertical ring high-gradient magnetic separators and electromagnetic slurry magnetic separators can also be used to remove impurities to obtain feldspar products that meet the requirements for ceramic raw materials.
Dense Medium Method：
Under normal temperature conditions, the density of spodumene in spodumene ore is slightly larger than that of gangue minerals such as quartz and feldspar, generally about 3.15 g/cm3. Generally, spodumene ore is sorted by using heavy liquid with a density between the density of spodumene, quartz and feldspar, such as tribromomethane and tetrabromoethane. Among them, the density of spodumene is greater than that of these heavy liquids, so it sinks to the bottom and is separated from gangue minerals such as feldspar and quartz.
Combined beneficiation method：
At present, it is difficult to obtain qualified lithium concentrates for “poor, fine, and miscellaneous” lithium minerals by a single method of beneficiation. The combined beneficiation method must be used. The main processes are: flotation-gravity separation-magnetic separation combined process , Flotation-magnetic separation combined process, flotation-chemical treatment combined process, etc.
Examples of spodumene beneficiation：
The main useful mineral of spodumene ore imported from Australia is spodumene, with a Li2O content of 1.42%, which is a medium-grade lithium ore. There are many other minerals in the ore. The gangue minerals are mainly feldspar, quartz, muscovite, and hematite mine etc..
Spodumene is graded by grinding, and the selected particle size is controlled to -200 mesh 60-70%. There are a large amount of primary fine-grained sludge in the original ore, and chlorite and other minerals that are easy to silt during the crushing and grinding process are often It will seriously interfere with the normal flotation of ore. The fine mud will be removed through desliming operation. Through the combined process of magnetic separation and flotation, two products, spodumene concentrate and feldspar concentrate, which can be used as ceramic raw materials, are obtained.
Post time: Jun-02-2021