Name and Location
Nolans rare earths project, Northern Territory, Australia.

Client
Arafura Resources.

Project Description
Nolans is one of the most advanced rare earths development projects globally. The Nolans Bore resource is rich in neodymium and praseodymium (NdPr) – the key rare earths used in high-strength permanent magnets.

The project has total mineral resources estimated at 47-million tonnes at 2.6% rare-earth oxides using a 1% cutoff grade.

The Nolans development report (NDR) describes in detail Arafura’s plans to develop its wholly owned Nolans rare earths project. The project will entail a mine, a concentrator, a rare earths intermediate plant and related infrastructure to be constructed and located at the Nolans site, in Australia’s Northern Territory. A rare earths separation plant will be built and located in an established chemicals industry precinct at an offshore location.

The proposed mining operation will use conventional openpit truck and excavator mining methods, supplemented by drilling and blasting for ore and waste.

Pit optimisation studies have generated schedules showing a mine life of 25 years, based on measured and indicated resources, and more than 40 years, based on total resources. Dilution is estimated at 11.4% (plus 0.1% mining loss) and 15.7% (plus 0.2% mining loss) respectively.

According to the NDR, geotechnical inputs, including pit slope parameters, have been developed for pit optimisations and pit design. A series of pit shells has been produced and the detailed pit design will be completed for the definitive feasibility study (DFS).

A strategic mining schedule for the measured and indicated optimisation scenario is based on a maximum overall mining rate of ten-million tonnes a year to produce an average of 900 000 t/y of plant feed. The life-of-mine optimisation scenario is based on a maximum overall mining rate of ten-million tonnes a year to produce an average of one-million tonnes of plant feed each year.

Meanwhile, the project’s post-beneficiation flowsheet has changed from a single complex, intended to be located at Whyalla, to a split configuration comprising a rare earths intermediate plant at the Nolans site and an offshore rare earths separation plant in an established chemicals precinct.

Sulphuric acid instead of hydrochloric acid will be used in the preleach circuit and the project no longer includes a chloralkali plant and hydrochloric acid recycle. It is no longer necessary to produce sodium hydroxide and hydrochloric acid on site, and the reduced quantities required will be imported to both processing complexes.

Beneficiation at the Nolans mine site will comprise crushing, grinding, magnetic separation and flotation to produce a blended concentrate.

The beneficiation flowsheet is defined with a high level of certainty and is ready to be progressed to DFS level.

Concentrate will be pumped through a slurry pipeline to a rare earths extraction plant at the Nolans processing site. Rare earths will be extracted from the concentrate by chemical processing to produce a high-quality rare earth intermediate product. This flowsheet is well developed, with some parts requiring limited confirmatory work to provide more detail for the certainty of the process. Detailed process design criteria, and equipment selection and sizing have been undertaken.

Tailings, residue and radionuclide retention will be confined to the Nolans site.

Rare earths will be separated into the final rare-earth oxide products at the offshore rare earths separation plant using solvent extraction, followed by precipitation and calcination.

Arafura’s detailed research programme at Ansto, including minipiloting and rare earths separation trials, has delivered design parameters for upscaling to a production-scale installation and the corresponding mass balance and raw-material requirements.

Net Present Value/Internal Rate of Return
The project has an estimated net present value of A$2.045-billion after tax, with a 10% discount rate.

The project has an internal rate of return of 21.4% and an after-tax payback of capital in the fifth year of operation.

Value
Overall capital costs, including contingency, are estimated at A$1.41-billion.

Duration
The NDR envisages construction to start in mid-2016 and production in early 2019.

Latest Developments
Arafura is closer to the development of its Nolans project, after the Northern Territory Environmental Protection Authority finalised the terms of reference for the project’s environmental-impact statement (EIS).

The receipt of the terms of reference will enable Arafura’s EIS consultants to recalibrate the scope of the EIS studies to ensure that the EIS addresses all the issues raised.

Meanwhile, work is continuing on a number of baseline studies for the Nolans project, including biodiversity, groundwater, emissions and archeology.

The company has also started to engage with key stakeholders earlier this year, along with social-impact assessments.

Arafura hopes to start production at the Nolans project in 2019, with production targeted at 20 000 t/y of rare-earth oxide equivalent.
Further, Arafura has reduced the operating costs at the project by about 7.4%, following a review of an optimisation programme.

At nameplate production, the Nolans project is expected to produce at an operating cost of A$14.51/kg, compared with the previous estimate of A$15.67/kg.

The decrease in operating costs reflects a material reduction in sulphuric acid and process residues, which are expected to impact favourably on the project’s environmental and community risks.

A final outcome of the optimisation programme is expected shortly.

Arafura has also undertaken a review of equipment and re-estimated capital costs for the project, which has not resulted in any significant change in capital expenditure of A$1.41-billion.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
Arafura Resources, tel +61 8 6210 7666, fax +61 8 9221 7966 or email media@arafuraresources.com.au.