Piedmont Lithium (ASX: PLL) has commenced a definitive feasibility study (DFS) for its integrated lithium hydroxide project in North Carolina based on an advanced conversion process developed by Finnish sustainable technologies specialist Metso Outotec.
The innovative alkaline pressure leach process aims to improve the project’s economics and produce the lowest environmental impact of any current lithium project worldwide.
The process works by omitting the acid roasting step of conventional spodumene conversion, thereby reducing air emissions from the chemical operations and eliminating the consumption of sulphuric acid and sodium sulphate waste products.
It is claimed to significantly reduce carbon dioxide emissions of Australian concentrates, when compared to Chinese conversion options, and has the potential to contribute to a lowering of capital and operating costs due to a streamlined flowsheet and lower reagent use.
Representatives from Metso Outotec will join Piedmont’s DFS technical team, which also comprises engineering firms Primero Group and Marshall Miller & Associates.
Piedmont chief executive officer Keith D Phillips welcomed the adoption of Metso’s new technology.
“Demand for locally and ethically-sourced battery raw materials is accelerating and we are engaging in multiple initiatives to meet this opportunity in the most sustainable ways possible,” he said.
“In adopting the Metso Outotec process, we hope to deliver enhanced DFS economics while positioning the Piedmont lithium project to have a lower environmental impact than any of the lithium hydroxide projects which are currently operating or in construction around the world.”
Mr Phillips said the DFS will also evaluate enhancements to Piedmont’s operations including installation of solar generating capacity and in-pit crushing systems, and the elimination of haul trucks.
These initiatives are expected to further improve carbon emissions and project economics.
The study is due for completion in late 2021, with a preliminary economic assessment of the integrated business scheduled before mid-year.
Construction of concentrate operations is expected to be completed by the end of 2022, with completion of the chemical plant due in 2023.