PERTH (miningweekly.com) – Lithium miner Pilbara Minerals has announced a final investment decision (FID) on the mid-stream demonstration plant at the Pilgangoora operation.

The joint venture (JV) with Calix is expected to deliver a superior value-added lithium product enabling lower product cost, reduced carbon energy intensity, and reduction of waste product logistics.

In full production, the project will produce more than 3 000 t/y of lithium phosphate from a 27 000 t/y spodumene concentrate feedstock mass.

The estimated construction cost of A$104.9-million will be partially funded with a A$20-million grant from the Australian government, with Pilbara Minerals funding A$67.4-million of the remaining budgeted construction expenditure, while Calix will pay the remaining A$17.5-million.

The spodumene concentrate feed will be purchased by the JV from Pilbara Minerals on commercial terms, and as manager of the JV, Pilbara Minerals will seek to sell all lithium phosphate produced from the demonstration plant on commercial terms to participants in the lithium supply chain.

First lithium salt is targeted for the June quarter of 2025, with the project to ramp up to steady-state production in the March quarter of 2026.

“Following further studies and pilot test work, we are delighted to be taking the next step in our mid-stream strategy with the construction and operation of a mid-stream demonstration plant with our JV partner Calix,” said Pilbara MD and CEO Dale Henderson.

“The mid-stream strategy has potential to materially improve the battery materials supply chain for lithium through reduction in carbon energy intensity, reduction in transport volumes and creating more value at the mine site. It has the potential to be a game changer compared to the traditional spodumene-to-chemicals processing route.

“The demonstration plant with Calix is an important step to further the development of the technology with the aim of commercialising the technology for application at the Pilgangoora operation and across the lithium industry through our commercialisation JV with Calix. This could, in time, open up an additional revenue stream for the company, he added.

Life cycle assessment studies commissioned by Pilbara Minerals have calculated that when using 100% renewable electricity for electric calcination, the carbon emissions intensity of spodumene calcination can be reduced by more than 90% when compared to using coal as the primary source of thermal energy in rotary kiln calcination, and by more than 80% when compared to the use of natural gas.

The assessments conclude that successful implementation of electric calcination on-site at a spodumene mine and concentrator could materially reduce carbon emissions intensity associated with spodumene calcination by more than 3 kg carbon dioxide equivalent per kilogramme LiOHᐧH_₂O when using renewable energy compared to using coal as the thermal energy source in rotary kiln calcination.

Pilbara said that potential reductions in carbon emissions are also anticipated from producing a mid-stream product by avoiding the transport of waste associated with spodumene concentrate.

Additionally, the project aims to enable greater value extraction from hard-rock lithium assets by allowing spodumene producers to better utilise mineral resources and move down the battery materials value chain by producing a higher-value intermediate product on-site. This will potentially enable more value to be captured onshore at the resource.

“We are delighted that the project has passed the FID milestone, and we thank the Australian government for their support,” said Calix MD and CEO Phil Hodgson.

“Together, we look forward to demonstrating the potential of our electric calcination technology to dramatically reduce the carbon footprint of Australian lithium. The success of the JV will also showcase the opportunity of combining Australian mineral and renewable resources with innovative Australian technology to enable the reliable and sustainable supply of value-added critical minerals to the world.”

Should the calcination technology be successfully demonstrated, Pilbara Minerals has the right to licence the technology from the JV for use in its own potential mid-stream or downstream commercial scale plants to produce lithium salts or chemicals, either at Pilgangoora or in respect of future projects that Pilbara Minerals may develop either alone or in partnership.

The parties to the JV may also seek to commercialise the technology through an incorporated joint venture having the exclusive worldwide right to licence the technology to third parties in respect of lithium processing applications.