Arafura Resources (ASX:ARU) has successfully completed bulk pre-leach piloting for its Nolans Neodymium-Praseodymium (NdPr) Project in the Northern Territory.
The Nolans project contains one of the world’s largest neodymium and praseodymium deposits, a valuable source of rare earth magnets.
The bulk pre-leach pilot plant was the third phase of Arafura’s final piloting of the Nolans process flow sheet.
It follows from the successful operation of the beneficiation pilot plant (phase 1) which delivered a high-phosphate concentrate (HPC) as feed to the bulk pre-leach.
This HPC was characterised by enhanced recoveries of phosphate (>90%) and the key magnet-feed rare earths NdPr (>82%), and efficient rejection of impurities.
Phase 2 of the piloting program (phosphate extraction) was successful in validating the metallurgical process.
Arafura then commenced operation of the phase 3 pilot in July, the main aim of which was to produce sufficient NdPr-rich pre-leach residue (PLR) for subsequent phases of the piloting program.
The plant processed around 4.3 tonnes of HPC, generated about 2 tonnes of PLR, and operated with online thickening and filtration to replicate the full scope of the pre-leach process.
The performance of the thickeners and filters met with expectations as did the extraction of phosphate from the HPC.
Planning is now underway for phase 4 of the Nolans Pilot Program - acid bake of PLR produced from the phase 3 bulk pre-leach pilot.
Construction and operation of the phase 4 pilot are scheduled for the September quarter of 2017.
Arafura is aiming to become one of the world’s largest suppliers of rare earth magnets, which are poised for significant growth supported by demand from the electric vehicle industry.