BHP’s entry into nickel sulphate ‘well timed’, cobalt sulphate may be next

PERTH (miningweekly.com) – Mining major BHP is reviewing the timing of its Stage 2 nickel sulphate plant at the Kwinana refinery, in Western Australia, on the back of high demand.

BHP Nickel West asset president Eduard Haegel said on Tuesday that potential customer visits had confirmed that the company’s entry into the nickel sulphate market had been well timed, with interest by customers significantly exceeding expectations.

Nickel sulphate is a key component in lithium-ion batteries that power electric vehicles.

The Kwinana refinery received a new lease of life when BHP earlier this year approved a $43-million Stage 1 project to produce 100 000 t/y of nickel sulphate hexahydrate. Stage 2, if approved, will double production to 200 000 t/y, making Nickel West the largest nickel sulphate producer in the world.

“With enormous scale benefits, the internal use of sulphuric acid from Kalgoorlie, and the synergies with the refinery, Nickel West could be one of the lowest cost nickel sulphate producers,” Haegel told delegates at the Paydirt nickel conference, in Perth.

Subject to regulatory approvals, BHP Nickel West expected to complete the Stage 1 plant in April 2019.

The Stage 1 operation will include a nickel powder leaching area, a purification circuit, a crystalliser with dewatering and drying modules, and the expansion of existing storage facilities to make way for two additional product bagging lines at the current Kwinana refinery.

The nickel sulphate plant will be fully automated and will not require any human intervention until the bagged product is ready for loading.

Meanwhile, Haegel told delegates that the company was also progressing testwork to produce a cobalt sulphate product.

The production of a cobalt sulphate product would require the installation of a solvent extraction plant within the refinery circuit to extract cobalt. However, Heagel noted that the Kwinana refinery was an ammonia leach circuit, and operated at higher temperatures than typically existed in traditional applications.

“This means that we have had to, and continue to do, extensive testwork to identify the most effective facility and reagent design,” he said.

“We are optimistic that we will finalise a design in the first half of calendar 2018 and will subsequently look to move to execution, subject to approvals.”

In addition, the company was also considering a cathode precursor plant at the Kwinana refinery, with BHP Nickel West conducting a concept study and a preliminary assessment of the technical and financial viability of such a facility.

“There are, of course, challenges in making precursor and these will take some time to work through, but the prospect of making cathode precursor is an exciting one. Our concept study will flag if these advantages are sufficient to build an economic case,” Haegel said.