How can the water usage in lithium mining be reduced

Reducing water usage in lithium mining is critical due to the enormous volumes currently required and the significant environmental damage linked to traditional methods. Several strategies and technological innovations are being used or developed to address this challenge:

Key Strategies to Reduce Water Usage in Lithium Mining

1. Use of Seawater Desalination
In regions like northern Chile, seawater desalination infrastructure is being developed to supply lithium (and copper) mining operations with water. This reduces reliance on local freshwater sources, thereby protecting surrounding ecosystems and communities from water depletion.

2. Water Recycling and Reuse (Closed-Loop Systems)
Modern lithium mining projects, such as the Thacker Pass mine, are designed to maximize water recycling and reuse within their processes. Thacker Pass uses a zero liquid discharge (ZLD) system which prevents the discharge of wastewater and minimizes freshwater consumption. They recycle nearly all the process water, which drastically reduces overall water use compared to traditional methods. Similarly, the A1 Lithium project plans to recycle 95% of its water, employing a closed-loop system to reduce water loss and avoid contamination risk from spills.

3. Adoption of Direct Lithium Extraction (DLE) Technologies
DLE is a promising technological innovation that extracts lithium directly from brine without relying on large evaporation ponds. This method significantly reduces water consumption since it does not require water evaporation, and it limits the environmental risks of toxic leaks. DLE also improves lithium recovery rates, making the extraction process more efficient and less water-intensive.

4. Mining Process Innovations Using Low-Water-Intensity Ore Types
Projects like Thacker Pass benefit from mining sedimentary clay lithium deposits, which allow for lower water and energy intensities during processing compared to traditional hard rock or brine evaporation methods. This geological advantage helps reduce water demand inherently.

5. Water Conservation Targets and Monitoring
Large mining companies are setting ambitious water reduction targets, such as Sociedad Química y Minera de Chile aiming to reduce water use by 65% by 2040 and brine extraction by 50% by 2028. These companies use data to monitor water use and implement best practices like leak repairs and treated wastewater reuse to minimize water impacts in water-stressed sites.

6. Use of Microbial Treatment Technologies
Emerging microbial technologies are being developed to treat mining wastewater, removing toxins and enabling reuse onsite. This reduces the overall fresh water needed and mitigates contamination risks.

Environmental Benefits of Reducing Water Use in Lithium Mining

Reducing water use and contamination helps preserve underground freshwater reserves and surface ecosystems, especially in vulnerable regions such as the Lithium Triangle in the Andes, where overuse has caused water table declines, salinization, wetland drying, biodiversity loss, and increased climate vulnerability.

In summary, water use in lithium mining can be significantly reduced by integrating seawater desalination, advanced recycling and reuse systems, direct lithium extraction technologies, mining of low-water-intensity ore types, strict water conservation targets, and new wastewater treatment methods. These approaches help mitigate environmental impacts while supporting the growing demand for lithium in the clean energy transition.