Germany: Lithium from Unconventional Sources Metallurgical Process Route to Provide Supply Security for European Renewable Energy Industry
Lithium Australia's use of mine waste to produce lithium-ion batteries formed the basis of a recently completed processing evaluation for the company's Sadisdorf lithium/tin project in Saxony, Germany. That evaluation contemplated the production of high-performance cathode powders from mica recovered from tin-mining operations there.
Sadisdorf/Germany — The processes required have been extensively pilot-tested and market evaluation of the types of cathode powders produced is ongoing in China and Japan. Results of the investigations allow the company to commit to the next step towards commercialising operations at the project and ultimately producing cathode powders in Europe. The manufacturer is of the opinion that, by situating a Si-Leach plant at Sadisdorf to treat locally available micas and converting the lithium chemicals produced to cathode powders, as has been previously demonstrated at pilot scale, the company could combine low capital intensity with high margins to reduce the European battery industry's reliance on imported lithium ion battery components.
Lithium Australia, through its wholly-owned subsidiary Trilithium Erzgebirge, has a 100 % beneficial interest in the project, which is currently on care and maintenance. Historically Sadisdorf was a tin-mining enterprise, the tin veins occurring within a 'greisen' (altered granite), with the pervasive alteration within the granite consisting of lithium micas. The project, which is situated near the border with the Czech Republic is close to Deutsche Lithium’s Zinnwald deposit and European Metals’ Cinovec deposit (Czech Republic).This location is significant in terms of its proximity to the rapidly expanding European electric vehicle and battery industries.
At present, the project contains an inferred resource of 25 million tons of 0.45 % Li2O. A three-hole diamond drilling campaign completed in May 2018 was designed to confirm historic data and test the outer boundaries of the mineral resource model. Drilling results from that programme suggest the potential for a future resource upgrade. In addition to lithium and tin, significant tungsten mineralisation was encountered in parts of the inner alteration (greisen) zone.
In light of the positive results from the aforementioned drilling campaign, an evaluation of processing options was initiated in the latter half of 2018 and finalised in January 2019.
The project concept involves the extraction of both tin and lithium from the deposit, initially by open cut mining. Zinnwaldite mineralisation (a mica containing the target lithium) is beneficiated by conventional wet, high-intensity magnetic separation and the cassiterite mineralisation (containing the target tin) via a combination of conventional flotation and gravity separation. The tin concentrate is considered of sufficient quality for direct sale, while the lithium concentrate is further processed hydrometallurgically using Si-Leach into lithium phosphate, with potassium sulphate as a by-product.
Opportunities being evaluated by Lithium Australia include:
- improvement in value via the conversion of lithium phosphate to a lithium-iron-phosphate cathode precursor material using VSPC Ltd proprietary technology;
- optimisation of cassiterite (the dominant tin mineral), and zinnwaldite (lithium mica) beneficiation and recovery efficiency; and
- performing a Si-Leach Generation 3 pilot-plant trial on a bulk composite sample.
Lithium Australia considers that the Project warrants further investment of funds, with a preliminary feasibility study now approved for implementation. Formal study planning activities will commence in March 2019 with a technical workshop in Germany. Attending will be participants from Trilithium Erzgebirge, Lithium Australia, VSPC and CSA Global.