Independence Group NL (ASX:IGO) has developed a new process, the IGO Process, to produce high-quality nickel sulphate from Nova project nickel sulphide concentrate, which is being proven in a downstream pre-feasibility study (PFS).
The PFS demonstrates that metal recoveries from the IGO process achieve extraction rates exceeding 97% of both the nickel and cobalt metal in the Nova nickel-cobalt sulphide concentrate feed.
Based on work completed to date, the IGO Process is low cost and well within the lowest quartile cost curve for the integrated production of nickel sulphate.
A “strategic metal of the future”
Independence Group managing director Peter Bradford said: “Nickel is a strategic metal of the future and is poised to benefit from the structural shift to energy storage and electric vehicles and the transition to increased use of nickel dominant, higher energy deposit NMC (nickel-manganese-cobalt) and NCA (nickel-cobalt-aluminium oxide) lithium-ion battery technologies in electric vehicles that deliver better battery performance.
“This combined with continued demand growth for nickel from the stainless steel and specialist nickel alloy markets will transform our industry.
“IGO has embraced this transformation to strategically focus on nickel and other metals critical to clean energy, with an interest in both upstream and downstream opportunities.
“Upstream, we have expanded our generative and greenfields exploration to drive the discovery of new nickel and copper projects to provide the nickel and copper world needs.”
IGO Process
The IGO process flowsheet combines seven proven technologies commonly used in the mining industry and can be simplified in four sequent steps:
- Leaching;
- Primary and secondary neutralisation;
- Cobalt and copper solvent extraction and precipitation; and
- Nickel solvent extraction and crystallisation.
Proposed IGO Process flowsheet to convert sulphide nickel concentrate directly to nickel sulphate.
Although metallurgical test work is well progressed significant opportunities remain to optimise the study including:
- Process flowsheet refinements
- Minimising waste streams by maximising by-products;
- Site selection;
- Scale and scalability; and
- External sensing of the nickel sulphate market and potential for partnership and collaboration
Next steps
Bradford added: “Further work remains to be done to optimise the process design to minimise waste and maximise by-product credits as we also continue to do trade-off studies to determine the optimum project location.
“We are excited by the results but plan to spend more time to test all strategic options for the study.”
Optimisation work streams have begun, and the PFS is now expected to be completed during the December 2019 quarter.
In parallel with the study, the company will begin marketing nickel sulphate concentrate offtake agreements for the period from the expiry of existing contracts in December 2019 and June 2020 until the downstream nickel sulphate project could potentially be operational.