Australian miner Sayona Mining Limited announced it is moving forward with the restart of a lithium carbonate production plant at its North American Lithium (NAL) operation in Quebec, bringing it closer to becoming a downstream producer of lithium chemicals. 

In late June, the company released the results of a preliminary study for the standalone lithium carbonate project, outlining the production of 372,000 tonnes of battery-grade lithium carbonate from 2.9 million tonnes of spodumene concentrate from the NAL mine over a project life of 16 years.

All-in sustaining costs per tonne of lithium carbonate are estimated to be $15,996.

Results from the study showed the project could generate a pre-tax net present value of $2.9 billion at an eight per cent discount rate and a pre-tax internal rate of return of 60 per cent. The study anticipates capital costs of $555 million and assumes an average selling price of $34,113 per tonne of lithium carbonate.

Brett Lynch, Sayona Mining’s managing director, said in a June 21 press release that taking advantage of existing infrastructure and assets will help accelerate NAL’s pathway to lithium carbonate production.  

Sayona Québec—a 75-25 joint venture between Sayona Mining Limited and American company Piedmont Lithium—purchased the NAL assets in August 2021 after two previous operators failed to make the operation profitable. The site includes mining and concentrator facilities, which will provide feedstock to the partially constructed lithium carbonate process plant, and waste and tailings management facilities. 

“Significantly, NAL is set to become the only lithium operation with a concentrator and carbonate plant all on the same site in North America,” Lynch said. “Lithium demand continues to increase and the Canadian and U.S. governments have clearly shown their intentions to develop a North American supply chain, from mining to processing and manufacturing.”

The company stated in the release that the lithium carbonate plant needs to be updated to reach its nameplate throughput capacity, which includes work on the hydrometallurgy portion of the carbonate plant. Planned additions to the original flowsheet include a sodium sulfate crystallizer and buffer tanks.

The pyrometallurgical section of the flowsheet also needs major upgrades, including the addition of a feed preheating system, a rotary calcine cooler, a ball mill, modifications to the acid-mixing circuit and the addition of an acid bake kiln to replace the existing acid reactor.

Based on the results of the preliminary study, Sayona plans to commission a definitive technical study for the project, and it is targeting production as early as 2026.

On March 30, Sayona Québec restarted production of spodumene concentrate at NAL, targeting four shipments from NAL totalling up to 120,000 tonnes by the end of 2023, which is expected to supply clients including LG Chem and Tesla.  

A definitive feasibility study of the NAL mine released in April stated its proven and probable reserves total 235,500 tonnes of contained lithium oxide from 21.7 million tonnes grading at 1.08 per cent.