Australia-based Arafura Resources Limited has awarded Hatch a contract to carry out Engineering and Procurement Services for the Nolans NdPR project hydrometallurgical plant.
The Nolans project in Australia will encompass a mine, process plant (comprising beneficiation, extraction and separation plants) and related infrastructure to be constructed and located at the Nolans site, 135 kilometers north of Alice Springs in Australia’s Northern Territory.
The project is underpinned by low-risk mineral resources that have the potential to supply a significant proportion of the world’s NdPr demand, according to the company. It is a globally significant and strategic NdPr project which, if developed, could become a major supplier of these critical minerals to the high-performance NdFeB permanent magnet market.
The project’s cornerstone asset is the Nolans Bore rare earths-phosphate-uranium-thorium (REE-P-U-Th) deposit, one of the largest and most intensively explored deposits of its kind in the world. The deposit contains a JORC 2012-compliant Mineral Resources of 56 million tonnes at an average grade of 2.6% total rare earth oxides (TREO) and 11% phosphate (P2O5) that extends to 215 meters below the surface. Two-thirds of the contained rare earths are in high confidence Measured and Indicated resources.
Mineral resources at Nolans.
The most abundant rare earth-bearing minerals at Nolans Bore are apatite, monazite (both phosphate minerals) and allanite (a silicate mineral). These mineral species present a highly desirable rare earth mix at Nolans Bore, with 26.4% of the mix represented by NdPr.
Open-cut mining will selectively target phosphate-rich material types in seven pit stages over the life of mine with ore being fed to a single-stage crushing and milling circuit at the process plant approximately 8.5 kilometers south of the mine.
Milled ore will initially be processed using flotation. This reduces the mass for subsequent processing and produces a phosphate-rich, rare earth-bearing concentrate, as well as tailings. Tailings will be pumped to a Residue Storage Facility (RSF) for containment and long-term management.
The concentrate will be fed to an adjacent extraction plant, where it will be subjected to a number of hydrometallurgical processes including pre-leach, sulfation, water leach, precipitation, dissolution, and purification. The extraction plant will produce 144,000 tonnes of fertilizer-grade (54%) phosphoric acid each year as a by-product of the pre-leach process. This product is earmarked for export and direct sale. Waste streams, including gypsum, from extraction processing will be neutralized before being pumped to an RSF.
Rare earth chloride from the extraction plant will be further refined at an adjacent separation plant into two final rare earth products for export and sale: 4,440 tonnes per annum of NdPr oxide and 470 tonnes per year of a mixed middle-heavy rare earth (SEG/HRE) oxide.
Hatch was selected from three international engineering firms through a competitive process to ensure full project understanding, cost assessment, and risk and liability management.
This next phase of the project will see front end engineering design (FEED) works completed over the next 9 months to advance engineering and equipment procurement. The resul t of this work will allow thecompany to tender a fixed price construction contract which will be the basis of making a Final Investment Decision (FID) in the second half of 2022.
In parallel, the Integrated Project Management Team, with KBR Pty Ltd and Wave International, will progress the remainder of the project as the Company prepares for a Nolans Final Investment Decision (FID), with work including:
Incorporating best practice ESG measures to ensure we meet our commitments to our global customers;
Scoping the Beneficiation Plant and Sulfuric Acid Plant which will be tendered as fixed price Engineering, Procurement and Construction contracts concurrently with the hydrometallurgical plant construction tender;
Ensuring all early works construction is ready for tendering concurrently with the hydrometallurgical plant construction tender;
Completing detailed mine design for the initial mining period to allow for tendering of the contract mining services following FID; and
Updating the overall project control budget and schedule to reflect the final design and tender submissions and to support FID.
Roskill observes that despite the potential, challenges associated with the rare earth mineralization and project funding remain, with the project requiring an estimated initial capital of US$768 million for development and commissioning.
In 2021, it is estimated that China will account for 57% of mined supply and 84% of refined production of rare earths. This has encouraged governments around the world to establish secure supply chains for critical raw materials. Despite the work to diversify the supply chain, particularly at the mined supply stage, Roskill believes refined supply and subsequent downstream processing will remain China-centred.