The Nolans rare earths project is an open-pit mine under development in the Northern Territory of Australia. The neodymium-praseodymium (NdPr) mine is recognised as a major project by the Northern Territory Government.
Arafura Rare Earths, a subsidiary of Australian mineral exploration company Arafura Resources is the owner and developer of the Nolans NdPr project.
A definitive feasibility study (DFS) for the project was completed in February 2019 while a final investment decision is anticipated to be made by 2020.
In July 2020, Arafura secured the mineral leases for the initial 25 years from the Northern Territory Government following the execution of a native title agreement (NTA) in June 2020.
The mine life is anticipated to be 33 years, with a total production capacity of up to 330,000 tonnes (t) of rare earths concentrate over the mine life.
The Nolans rare earths project is expected to supply up to one-tenth of the world’s total demand for NdPr oxide which is used in neodymium magnets (NdFeB), a key element in green energy technology products including portable electronic devices, e-vehicles, wind turbines, aerospace products, and medical equipment.
Nolans NdPr project location, geology, and mineralisation
The Nolans NdPr deposit is located at Nolans Bore, approximately 135km north-west of Alice Springs in the Northern Territory of Australia. It will be well-connected with the Stuart Highway and Darwin-Adelaide railway.
Nolans Bore lies in the Aileron Province of the Arunta Region. The deposit at the site is covered by a thin layer of alluvium, colluvium, and calcrete with scattered outcrops of fluorapatite rich rare earth element (REE) mineralisation and metamorphic host rocks that occur in both sides of a palaeochannel up to five metres deep.
The REE mineralisation of the deposit is grouped into three evolutionary stages, including primary, overprinting hypogene and supergene.
The primary mineralisation occurred towards the end of the Chewings event, overprinting hypogene during Alice Springs Orogeny, and supergene mineralisation occurred since the Mesozoic period.
Rare earth reserves and production at Nolans project
The Nolans mine site has total reserves of 29.5 million tonnes (Mt), including 5Mt of proven and 24.6Mt of probable ore reserves.
The NdPr enrichment in the resources is approximately 26.4%, while the proportions of phosphorus pentoxide (P2O5) and the total rare earth oxides (TREO) are 13% and 2.9% respectively.
Initially, the Nolans mine is expected to annually produce approximately 14,000 tonnes per annum (tpa ) of total rare earth oxides including 3,600tpa of NdPr, as well as 110,000tpa of phosphoric acid as a by-product.
Mining at Nolans NdPr project
The Nolans NdPr project will employ open-cut mining method for extracting ore. Milled ore will be processed at the nearby process plant, which is situated about 8.5km south of the mine.
The ore will undergo a single-stage crushing and milling before passing through chemical processing, baking, water leach, precipitation, and purification to produce NdPr concentrates. The impurities produced in the process will be pumped to a residue storage facility.
The leased area will comprise the mine site, a process plant with beneficiation, extraction, and separation facilities, waste storage facilities, and an accommodation village for 400 people. A slurry pipeline will be connected to a chemical processing plant that will produce the rare-earth rich intermediate products.
A waste management facility will be built to manage the waste streams including waste rock from mining, tailings, and chemical processing residues that will contain phosphate, thorium, and small amounts of uranium.
A gas-fired power plant will fulfill the electricity needs of the mine site and accommodation village.
Hatch, an engineering company with expertise in energy, metals, infrastructure, digital, and investments markets sectors, was engaged as lead engineering study manager for the DFS of the project.
Korean chemical manufacturing company OCI will oversee operations at the rare earths separation plant in a joint venture with Arafura.
Arafura also partnered with Bossong Engineering to execute a large-scale pilot plant.
KBR, along with subcontractor Wave International, will provide integrated project management services for the Nolans project.
USA Rare Earth was contracted for the treatment and processing of high purity mixed middle-heavy rare earths carbonate product from the Nolans deposit.