PERTH (miningweekly.com) – Nickel miner Western Areas has approved a A$22-million enhancement project at its Forrestania mill, in Western Australia.

The mill enhancement would process one of the tailings streams from one of the flotation plants, which contains valuable amounts of nickel that could not be recovered into concentrate by traditional flotation methods.

This stream would be leached at atmospheric pressure, using Western Areas’ patented BioLeach technology, in fiberglass reinforced polyvinylchloride tanks to recover the additional contained metal.

Mill recoveries were expected to increase by between 3% and 5% over the life of the mine, with up to an additional 1 200 t/y of nickel-in-concentrate recovered.

Western Areas MD Dan Lougher said on Monday that the decision to proceed with the mill enhancement was another example of the company investing in value-adding organic projects, which improve the efficiency of operations at Forrestania over the life of the mine.

“Investment in the mill enhancement follows an extremely robust feasibility study, incorporating a lengthy period of pilot plant testing which demonstrated the success in applying our patented BioLeach technology on our sulphide ores in a controlled environment.”

Lougher noted that the mill enhancement was expected to produce attractive economic returns and was another example where Western Areas would deploy relatively modest capital to generate operational efficiencies in a structured, smart and disciplined manner.

The enhancement project was expected to have a unit cash operating cost of some A$2.42/lb of nickel-in-concentrate and would have an internal rate of return of 39%, with payback expected within 39 months, using consensus nickel prices.

Construction of the project was expected to take some six months to complete, and the project would likely be commissioned and ramped up in July 2016.