Preston plant sets new nickel precedent

Producing its first metal from the Bulong nickel/cobalt project has set a new precedent for WA-based miner Preston Resources Limited.

Commissioning the Bulong operation, leading up to first metal production, has set a benchmark in the development of metal extraction and refining technology, according to Preston managing director Adrian Griffin.

He said it was the first time anywhere in the world that nickel metal had been produced on a production scale direct from high pressure acid leach by hydrometallurgical processing (processing in solutions) without generating any intermediate solid phases. The nickel is dissolved from the ore and the solutions are purified and metals electroplated direct from the solutions.

“The plant has produced nickel metal and cobalt sulphide, the latter being accumulated to expedite commissioning of the cobalt refinery,” Mr Griffin said.

“We are pleased with the rapid advance of commissioning to date, which has seen the production of first metal earlier than anticipated. This should permit commercial production to commence around the end of March.”

Preston settled the acquisition of Bulong from Resolute Resources Ltd for $319 million in November 1998 and took over the project when commissioning was at an advanced stage.

Bulong is located 30 kilometres east of Kalgoorlie and incorporated the low-cost, high-pressure acid leach (HPAL) process used successfully at Moa Bay in Cuba for more than 30 years. The Bulong process was the subject of 10 years of development.

The project has a resource of 140 million tonnes grading at 1 per cent nickel and 0.1 per cent cobalt, for 1.4 mt of nickel metal.

The planned throughput of the plant is 600,000 tonnes of ore to produce up to 9,600 tonnes of London Metal Exchange grade nickel and 1,000 tonnes of 99.8 per cent cobalt per annum.

The current project life is 25 years with the potential to expand the resource.