Location: Tibet Autonomous Region
Water Source: Salt Lake Brine
Capacity: 120m³/h
User: Zijin Mining
Purpose: Lithium Extraction from Salt Lake Brine
Commissioning Date: August 2023
PSI's latest generation of customized TFN fractional salt nanofiltration membranes boasts exceptional anti-fouling and anti-scaling properties. Leveraging the highly customizable nature of TFN technology, it enables optimal membrane performance design tailored to different salt lakes and various lithium extraction processes through membrane methods. This provides core technical support for reducing costs, improving efficiency, and optimizing processes in lithium extraction from salt lakes. The right figure shows PSI's TFN fractional salt nanofiltration membranes at the lithium extraction project site in Ali Salt Lake, Tibet.
The qualified stripping solution was treated with only two stages of PSI NF, producing water with magnesium at 2.9 mg/L and calcium at 2.25 mg/L. The rejection rates were >99% for magnesium and >98% for calcium, while the lithium transmission rate reached 96.6%. Under an operating pressure of 1 MPa, the flux reached nearly 20 LMH. The performance significantly outperforms traditional mainstream imported fractional salt nanofiltration membranes. The optimization of the membrane treatment process for the qualified stripping solution has been completed. By replacing the conventional three-to-four-stage nanofiltration purification with a two-stage PSI TFN system, the requirements for hardness removal and lithium transmission have been successfully met.
