Australia's Jervois Mining has revealed plans to integrate a pressure oxidation leach circuit (POX) at its Sao Miguel Paulista (SMP) nickel-cobalt refinery, in Brazil.

The company in October last year announced plans to acquire the refinery from Companhia Brasileira de Aluminio (CBA) – a subsidiary of Votorantim – for $22.5 million, payable in tranches, and in December made the first tranche payment.

The company appointed Elemental Engineering to start modeling on the refinery flowsheet in order to optimize product integration, including hydroxides and carbonate products, oxides and sulfide concentrates as part of a restart feasibility study.

The company on Tuesday said that a decision has now been taken to integrate a POX leach circuit at the refinery, which would offer a number of advantages compared to roasting concentrates, including high metal recovery, low overall operating costs, enhanced environmental and social governance metrics owing to lower emissions and energy use, and improved refined product purity. The introduction of a POX autoclave also opens up greater capacity to leach other hydroxide and carbonate feed products, maximizing existing refinery capacity, Jervois Mining said.

Jervois Mining will process sulfide concentrates produced at its Idaho cobalt operations through this integrated POX leach circuit, while third party concentrates could also be potentially introduced into the POX process with these concentrates.

With initial third-party discussions proving positive, Jervois Mining has taken the decision to reserve the maximum amount of copper capacity at its Sao Miguel Paulista refinery for third parties, meaning that the construction of the Idaho cobalt project is being advanced on the basis of the production of separated cobalt and copper concentrates.