With the development of technology, the popularity of electronic equipment, and the rise of the new energy industry, the consumption and demand of lithium ore increase correspondingly, and it is also known as "energy metal drives the world forward.
In production, the common lithium ore processing methods are mainly hand separation, flotation separation, heavy medium separation, and combined separation methods.
Use the table of contents below to navigate through the guide:
The hand separation method can be used for the preliminary screening of lithium ore. According to the differences between lithium ore and gangue minerals in color, appearance, and luster, the waste rock can be manually picked out to improve the grade of lithium ore in subsequent separation operations.
For lithium ore processing, the hand separation method is often used to separate coarse crystal lithium ore, generally, the ore particle size is between 10-25mm, and the width is not more than 1200mm. The belt speed is controlled in 0.2~ 0.4m/s.
The flotation method is the main lithium ore processing method at present, all lithium ore with industrial value can be enriched by the flotation method, especially the fine-grained disseminated lithium ore. The common lithium ore flotation methods are positive flotation and reverse flotation.
The lithium ore positive flotation method means adding the strong alkali to the pulp after the lithium ore is ground (avoid the mud phenomenon caused by over-grinding). After high concentration, strong agitation, and many times of scrubbing and desliming in an alkaline medium, the lithium concentrate was directly flotation by adding oleic acid and soap salt as collectors, and the gangue minerals are left in the tank. There is no need to add inhibitors in the flotation process.
Lithium ore reverse flotation method means add the starch, dextrin to suppress the floating of lithium ore in an alkaline environment while using the cationic collector to make silicate gangue minerals float to the pulp surface, the product left in the tank is lithium concentrate.
If the lithium ore contains iron minerals, the foaming agent (eg. HF, resin acid salt) can be added to further remove impurities (such as iron minerals).
Generally speaking, the specific gravity difference between lithium minerals and gangue minerals is no more than 0.2-0.5g/m3, which is not suitable for gravity separation by shaking table or jig. Therefore, the heavy medium separation method can be used to make lithium ore as the heavy mineral product, while gangue mineral is the light product.
After ore washing and desliming, the lithium ore is mixed with a heavy medium (mainly refers to the heavy suspension), and then sent to the heavy medium cyclone for separation with 0.05-0.20Mpa, the heavy products, and light products can be separated. The heavy products become the lithium concentrate after de-medium by the sculping screen, and the light products become the tailings after de-medium by the sculping screen, whose main groups are quartz, feldspar, and biotite.
In nature, the lithium ore has complex components, which is difficult to get qualified lithium concentrate by a single beneficiation method sometimes. If necessary, the combined separation method can be used for lithium ore processing, such as flotation-magnetic separation method, flotation-gravity separation-magnetic separation method, flotation-chemical treatment method.
Taking the flotation-magnetic separation method as an example, the lithium concentrate obtained by the flotation method sometimes contains more iron. In order to obtain the low-iron lithium ore and improve the product grade of lithium concentrate, the magnetic separation method can be used as a major auxiliary measure to improve the quality of lithium concentrate. The commonly used magnetic separation equipment includes vertical ring pulsating high gradient magnetic separator and wet high-intensity magnetic separator.
The above are the four common lithium ore processing methods. It is suggested to carry out the mineral processing test and customize the scientific beneficiation process and equipment according to ore properties and investment budget, thus avoiding the waste of resources.