POSCO signed an off-take agreement with Pilbara Minerals for the Pilgangoora project in February 2018. Image courtesy of POSCO.
Construction of the 2Mtpa Pilgangoora stage 1development project was completed in July 2018. Image courtesy of Pilbara Minerals.
The stage 2 Pilgangoora expansion project is expected to produce 800,000t of high-quality spodumene concentrate a year. Image courtesy of Pilbara Minerals.
The spodumene and tantalite concentrate from the Pilgangoora project is shipped at Port Hedland. Image courtesy of Pilbara Minerals.
The stage 2 Pilgangoora expansion project is expected to commence operation by the end of 2019. Image courtesy of Pilbara Minerals.
The Pilgangoora project achieved the first shipment of spodumene concentrate in October 2018. Image courtesy of Pilbara Minerals.

Pilgangoora Lithium-Tantalum project is located in the Pilbara region, approximately 120km south of Port Hedland, Western Australia. The mine was officially commissioned in November 2018.

Pilbara Minerals is the owner and developer of the Pilgangoora project, which is considered to be one of the world’s biggest lithium development projects.

The project aims to produce high-quality spodumene concentrate (lithium) along with tantalite concentrate (tantalum) as a by-product.

The Pilgangoora project is being developed in two stages. The stage one development called for a two million tonne per annum (Mtpa) mining and processing operation for a period of 36 years, which is planned to be increased to 5Mtpa over a mine life of 17 years, in the stage two expansion project.

Pilgangoora project development details

The definitive feasibility study (DFS) for the 2Mtpa stage one development project was completed in September 2016, which predicted annual average production of 330 kilotonnes per annum (ktpa) of 6% spodumene concentrates and 274,000lb of tantalite concentrates.

Construction on the project started in January 2017 and was completed in July 2018. The project achieved the first shipment of spodumene concentrate in October 2018.

The DFS for the 5Mtpa stage two expansion project was completed in August 2018. It predicts an annual average production of more than 800ktpa of high-quality spodumene concentrates and 800,000lbs of tantalite.

Pilbara Minerals announced the final investment decision on the $231m expansion project in November 2018 and expects its commissioning by the end of 2019.

Geology and mineralization

The Pilgangoora Lithium-Tantalum project is located on the western flank of the East Strelley Greenstone Belt, within the Archean North Pilbara Craton.

The Greenstone Belt consists of a sequence of mafic dominated supracrustal rocks. The mineralization for the Pilgangoora project occurs in a number of north-south trending pegmatites, with strike lengths up to 1,250m.

Pilgangoora mine reserves

The Pilgangoora Lithium-Tantalum project was estimated to hold 108.2Mt of proven and probable reserves grading 1.25% Li2O (Lithia), 120ppm Ta2O5 (tantalite) and 1.17% Fe2O3, as of September 2018.

Mining and processing for the Pilgangoora lithium-tantalum project

Pilgangoora is a conventional drill, blast, load, and haul open-pit mining operation.

The run-of-the-mine ore is sent to the concentrator plant where it undergoes two-stage crushing, dense media separation, gravity separation, grinding through high-pressure grinding rolls (HPGR), flotation, magnetic separation, and dewatering for the production of concentrates.

The concentrator plant is designed to produce chemical-grade spodumene, technical-grade spodumene, and tantalite concentrate.

The capacity of the concentrator plant will be expanded with the installation of a parallel 3Mtpa ore processing circuit, as part of the stage 2 expansion of the Pilgangoora project.

The concentrates produced at the processing facility are transported to the Wedgefield bulk storage facility at Port Hedland for shipping.

Lithium off-take agreements for the Pilgangoora project

Pilbara Minerals has signed two binding off-take agreements for the 2Mtpa stage one project with China’s General Lithium and Ganfeng Lithium, who have agreed to buy up to 140ktpa and 16oktpa of  6% chemical-grade spodumene concentrate for an initial of period six years and 10 years, respectively.

Pilbara Minerals has also secured two more off-take agreements with the Chinese pick-up and sport-utility vehicle manufacturer Great Wall Motor Company and POSCO, for up to 150ktpa and 240ktpa of spodumene respectively from the 5Mtpa expansion project.

Infrastructure for the expansion

The Pilgangoora Lithium-Tantalum project site is accessed by road from the Great Northern Highway and well connected to the Port Hedland.

Pilgangoora has an existing diesel-fired power generation facility, which will be expanded to 25MW with the installation of a gas-fired generating unit, as part of the stage 2 expansion project.

The 5Mtpa expansion project will require 1.5GL of water a year, which will be sourced from third parties by developing an additional borefield near the mine site.

The storage capacity of the existing tailings management facility (TMF) of the project will also be increased by raising the height of the three existing cells.

Contractors involved

RCR Tomlinson was the engineering, procurement and construction (EPC) contractor for the 2Mtpa processing plant for the Pilgangoora Lithium-Tantalum project. It engaged Primero and Minnovo as key technical and engineering subcontractors for the project.

RCR Tomlinson was also the front-end engineering and design (FEED) contractor for the processing plant.

NRW was engaged for the bulk civil earthworks for the project. A joint venture of Njamal Services and Pilbara Resource Group was contracted for the camp facility of the project, while the joint venture between Action Industrial Catering and Njamal Services was awarded the camp service contract.

Trepanier was engaged for geological study and resource estimates, whereas AMC Consultants provided mine design during the DFS for the 5Mtpa expansion project.

Minnovo Engineers was consulted for the process plant infrastructure, while ATC Williams provided TMF design as well as geotechnical consulting services during the DFS.