Piedmont Lithium is looking for project financing and final permits for a proposed US$809 million lithium hydroxide plant in Tennessee, USA, after filing a definitive feasibility study outlining a solid economic case for a 30,000 tonnes-per-annum operation.
The planned capital expenditure is a material increase from the $572m capex in Piedmont’s March 2022 preliminary economic assessment, while projected steady-state LiOH all-in sustaining conversion costs at US$2952/tonne compare with $2572/t in the earlier study.
Piedmont has a $26,000/t lithium hydroxide sales price assumption in the DFS versus $22,000/t in the PEA.
It hopes to start plant construction in 2024 and will look to source 196,000tpa of 6% Li2O spodumene concentrate – purchased at market rates – from Ghana and Canada. Piedmont has offtake rights to 50% of spodumene concentrate output from Atlantic Lithium’s Ewoyaa project in Ghana and North American Lithium’s Authier project in Quebec.
ASX and Nasdaq-listed Piedmont says its Tennessee lithium hydroxide conversion flowsheet features Metso Outotec’s alkaline pressure leach conversion process rather than traditional acid roasting. It says eliminating sulphuric acid use cuts expected solid waste generation and air emissions.
“We believe our entire conversion method will be more efficient and environmentally sustainable than conventional acid-roasting spodumene-to-hydroxide technologies, resulting in a process that is safer for employees, the environment and the community,” Piedmont says.
“While Metso Outotec’s pressure leach process is new to the lithium industry, it has been proven in other applications, and we expect it will be adopted and proven by other lithium producers ahead of our timeline.”
Piedmont CEO Keith Phillips said: “America’s pro-EV and battery manufacturing policies are providing an advantage to Piedmont at a time when many analysts are projecting lithium shortages to continue into the 2030s. Piedmont’s selection for a $141.7 million grant last year by the US Department of Energy exemplifies America’s commitment to developing a domestic lithium supply chain.”
Piedmont has US-based Kiewit Engineering doing front-end engineering design work on the proposed Tennessee plant. Primero Group Americas, part of ASX-listed NRW Holdings, is in charge of LiOH plant design.
Finland’s Metso Outotec has done pilot plant testwork using a spodumene concentrate sample derived from Piedmont’s Carolina lithium project. It started further bench-scale alkaline pressure leach testwork in the second half of last year using spodumene concentrate samples sourced from Ewoyaa and Authier.
ASX-listed Piedmont’s shares are up about 21% year-to-date at 80c, capitalising the company at circa-$1.5 billion.