Piedmont Lithium’s plan to build out an integrated lithium hydroxide business from a base in North Carolina, USA, has advanced with the release of a scoping study that, it says, confirms that Carolina Lithium will be one of the world’s largest and lowest-cost producers of lithium hydroxide with a “superior” sustainability footprint.

Piedmont Carolina Lithium contemplates a single, integrated site, comprising quarrying, spodumene concentration, by-products processing, and spodumene conversion to lithium hydroxide at its site in Gaston County. There are currently no such integrated sites operating anywhere in the world, with the company saying the economic and environmental advantages of this strategy are compelling.

The latest study outlined a production target of around 4.96 Mt of 6% Li2O spodumene concentrate (SC6), averaging approximately 248,000 t/y of SC6 over the 20-year mine life. This equates to an average of 1.95 Mt/y of ore processed, totalling some 37.4 Mt of run-of-mine ore at an average grade of 1.09% Li2O (undiluted) over the 20-year mine life.

Of the total production target of 4.96 Mt of SC6, some 1.19 Mt will be sold to third parties during the operational life and approximately 3.77 Mt will be supplied to Piedmont’s chemical plant operations for conversion into lithium hydroxide. This results in a total production target of about 582,000 t of lithium hydroxide, averaging approximately 29,095 t/y of lithium hydroxide over 20 years, the company said. The study also assumes production targets of 4.83 Mt of quartz concentrate, 7.51 Mt of feldspar concentrate, and 1.34 Mt of mica concentrate over the life of operations.

Piedmont envisages a total initial capital cost of $838.6 million for the project and an after-tax net present value (8% discount) of $1.92 billion.

While still very much preliminary, the flowsheet and mining process for this planned operation is of interest to any lithium developer looking for a ‘sustainable’ mining footprint.

The company currently envisages using a Metso Outotec alkaline pressure leach process as part of its plan. This will reduce emissions, eliminate sulphuric acid roasting and reduce solid waste, it said.

At the same time, in-pit crushing and conveyor systems are on the agenda, eliminating mining trucks in the study to reduce fossil fuel consumption.

Piedmont has also been working with a solar developer to build and operate a solar farm on Piedmont property capable of producing electricity to supply up to 100% of Piedmont needs.

The company will also co-locate all operations on the same proposed site in Gaston County to minimise any transit and allow unused by-product streams to be repurposed for site redevelopment, it said. This adds up, Piedmont says, to highly efficient land and water use compared with South American lithium brine production.

Keith D Phillips, President and Chief Executive Officer of Piedmont, said: “We are exceedingly pleased with the results of our updated scoping study. The economics of our project continue to impress, but I am particularly proud of the project’s sustainability profile.

“As we move forward to complete a definitive feasibility study for Carolina Lithium later in 2021, Piedmont has engaged Evercore and JPMorgan as financial advisors to evaluate potential strategic partnering and financing options for its North Carolina project. Given the project’s unique position as the only American spodumene project, with world-class scale, economics, and sustainability, we expect strategic interest to be robust.