ioneer Ltd (ASX:INR) has achieved many of its key objectives from the pilot plant for the Rhyolite Ridge Lithium Boron Project in Nevada, US.
The pilot plant facility at Kemetco Research in Vancouver, Canada has provided opportunities to optimise and simplify the pre-feasibility study (PFS) process flowsheet prior to completion of detailed engineering design of the process plant.
Notably, high-quality lithium and boron product samples from the pilot plant have been sent to thirty potential off-take partners.
The strategic and off-take partner discussions are progressing well with twenty potential partners having toured the pilot plant as part of their due diligence.
The definitive feasibility study (DFS) will be completed in Q1 2020 once process enhancements are incorporated into engineering design.
ioneer managing director Bernard Rowe said: “The pilot plant is an integral part of the Rhyolite Ridge Definitive Feasibility Study.
“In testing the integrated process flowsheet at pilot scale, we have collected the detailed data that has allowed us to identify areas that can be further enhanced and optimised to support detailed design engineering for the DFS and beyond.
“These valuable learnings will further ensure Rhyolite Ridge reaches its potential to be the largest producer of lithium in the United States, and to be in the lowest quartile of the lithium cost curve globally.
“Importantly, the pilot plant has demonstrated the project’s ability to produce high-quality lithium and boron products that have been sent to potential customers as part of off-take discussions. Given strong customer interest and the quality of our products, we are confident that our products will receive widespread customer acceptance and lead to off-take agreements important to funding project development.”
DFS progress and completion
Most components of the DFS are near complete with only the lithium-boron processing areas to be optimised subject to the outcomes of further pilot plant test work.
Key parameters of the DFS are in line with the Rhyolite Ridge PFS:
- Open-pit mine plan to be based on the June 2019 mineral resource with improved boron grades;
- Ore crush and vat sizing to provide high recoveries of lithium and boron into a pregnant leach solution; and
- Ore processing rate averaging 2.7 million tonnes per annum predicated on the onsite acid plant producing 3,500 tonnes per day.
The DFS has provided greater confidence in capital expenditure estimates, such as for the sulphuric acid plant where firm bids have been received.