PERTH (miningweekly.com) – A definitive feasibility study (DFS) into the Ewoyaa lithium project, in Ghana, has increased the project’s cost estimate from the $125-million estimated in the prefeasibility study (PFS) to $185-million.

Triple-listed Atlantic Lithium on Thursday reported that the DFS was based on a 3.6-million-tonne spodumene concentrate production over a mine life of 12 years. The DFS estimated a post-tax net present value of $1.5-billion with a free cash flow of $2.4-billion and life-of-mine revenues of $6.6-billion.

The study also estimated C1 cash operating costs of $377/t of concentrate free-on-board, after by-product credits from conventional opencut mining, and an all-in sustaining cost of $610/t.

“The DFS has reaffirmed the Ewoyaa lithium project’s impressive economic outcomes and profitability potential, providing improved confidence in Ewoyaa’s ability to become a significant, near-term producer of spodumene concentrate,” said Atlantic CEO Keith Muller.

“The study indicates payback within only 19 months and maintains a low capital intensity, further reinforcing Ewoyaa’s position among the leading pre-production hard rock lithium assets globally.

“The increase in capex from the PFS results from the inclusion of the modular dense media separation (DMS) units and the increased throughput of 2.7-million tonnes a year. Early revenue generated by the modular DMS units will reduce peak funding requirement for the mine build, strongly justifying these developments. Furthermore, this will provide a valuable opportunity to train national staff and engineer out any mining, materials handling or logistics bottlenecks ahead of large-scale operations commencing for a potentially quicker commissioning phase,” said Muller.

“The deployment of the modular DMS units has been reallocated from Stage 2 to Stage 1 of the project’s development. Stage 2 includes the evaluation of a Feldspar circuit, a by-product of the DMS process that we intend to supply to the local Ghanaian ceramics market, and a flotation circuit, further enhancing the project’s economics.

“Ewoyaa’s favourable mineralogy enables a simple flowsheet comprising a three-stage crushing facility and DMS processing from conventional, openpit mining to produce a spodumene concentrate proven suitable for carbonate, sulphide or hydroxide conversion. Due to its grade, the project’s coastal location and against the backdrop of the global decarbonisation movement, demand from off-takers for product from Ewoyaa has been strong.”

Atlantic has previously said that the company was hoping to be in production at Ewoyaa within the next two years.

Lithium major Piedmont is working towards a 50% stake in Ewoyaa, spending $17-million on exploration funding and the completion of a DFS, and also committing to half of the capital cost to develop the project.