Salt Lake Lithium Extraction Process

‌Working Principle

Lithium extraction from salt lakes primarily relies on membrane separation technology, with different process designs for sulfate-type and carbonate-type salt lakes to efficiently separate lithium ions and remove impurities.

Sulfate-Type Salt Lakes:

For low salinity brine, the membrane system can be applied directly. After pre-filtration, the raw brine enters the membrane separation system. Nanofiltration (NF) and reverse osmosis (RO) membranes are used to remove ions such as calcium, magnesium, and sulfate, concentrating the lithium ions and significantly reducing the magnesium-lithium ratio.

For highly concentrated brines, an adsorption process is first employed to enrich the lithium ions before further treatment with membranes to remove impurities, ultimately achieving lithium extraction.

Carbonate-Type Salt Lakes:

Similarly, pre-filtered brine from carbonate-type salt lakes is treated through multiple stages of membrane processing to remove impurities and concentrate lithium ions. The membrane technology effectively reduces the magnesium-lithium and carbonate-lithium ratios, improving lithium extraction efficiency.



Product Features

Adaptable to Different Salt Lake Types: Specialized membrane-based lithium extraction processes are developed for both sulfate-type and carbonate-type salt lakes, allowing flexibility in handling various mineralization levels.

Efficient Impurity Separation: Membrane technology efficiently removes ions like calcium, magnesium, and sulfate, reducing the magnesium-lithium ratio and improving lithium purity. For example, the magnesium-lithium ratio in a sulfate-type salt lake can drop from 28:1 to 1.6:1 after membrane treatment, and the carbonate-lithium ratio in a carbonate-type lake can drop to 2:1.

Flexible Membrane Treatment: Different process flows are used depending on the mineralization of the lake. Low-mineralization brine can enter the membrane system directly, while high-mineralization brine requires prior adsorption treatment.

Environmental and Economic Benefits: Membrane technology is an environmentally friendly method for lithium extraction, reducing the use of chemical reagents, minimizing wastewater discharge, saving resources, and enhancing economic efficiency.




Applications

Salt Lake Lithium Extraction Projects: Applicable to sulfate-type and carbonate-type salt lakes in regions like the Qinghai-Tibet Plateau, especially for salt lakes with high magnesium-lithium ratios and high mineralization. Membrane technology significantly improves lithium extraction rates.

New Energy Industry: The high-purity lithium extracted can be used in lithium batteries and energy storage devices, providing essential raw materials for electric vehicles and renewable energy storage technologies.

Mining and Resource Recovery: Membrane-based lithium extraction technology is not only suitable for large-scale salt lake development but also for the efficient utilization and recovery of other lithium resources.