Polymetal is to expand Amursk POX plant
The debottlenecking project will expand the capacity of the existing Amursk POX plant by approximately 50% in terms of concentrate processed. The key additions to the equipment will comprise a second oxygen plant, an autoclave discharge thickener, separate filters for thickener underflow, and upgrades for heat recovery and water treatment systems.
The project will enable Polymetal to retain approximately 50% of the Kyzyl concentrate for in-house treatment as opposed to a 3rd party off-take. Kyzyl’s flowsheet envisions gravity separation of the collective flotation concentrate into high-carbon and low-carbon streams. Extensive internal and external metallurgical and mineralogical testing confirmed the feasibility of treating the low-carbon material through the current POX circuit at Amursk.
POX processing is expected to improve effective gold recovery from concentrate by 3-4 percentage points as well as to bring down processing and transportation costs by $150-250 per tonne of concentrate. An alternative processing route will strengthen Polymetal’s commercial position on the concentrate market vis-à-vis off-takers.
Polymetal plans to ramp up the debottlenecked POX plant to full expanded capacity in the second half of 2018, in time to take first feed from the Kyzyl concentrator. Associated capital expenditure is estimated at US$ 55 million including contingency, to be predominantly incurred during 2017 and 2018.
Polymetal is continuing to undertake extensive metallurgical testwork and evaluate its ability to use high-temperature (230-240C) POX technology to process high-carbon Kyzyl concentrate and third-party feedstocks. A decision is expected in late 2018 or early 2019, in conjunction with the ramp-up of Kyzyl and an investment decision on Nezhdaninskoye project.
“We believe capital-light debottlenecking of the Amursk POX plant is the best approach given the steady increase in Polymetal’s refractory reserve base”, said Vitaly Nesis, Group CEO of Polymetal. “The project leverages existing infrastructure and skills base to strengthen our competitive advantage in the industry and materially improve the economics of our flagship Kyzyl project”.