PJSC Polyus announces that the Natalka mill has reached the level of above 80% of its design throughput capacity of 10 Mt on an annualised basis. Natalka has produced more than 40,000 oz of gold since the beginning of the year. Following the ramp-up, the mill will be producing some 450,000 oz of gold annually. Pavel Grachev, CEO of Polyus, commented: “This is an important milestone in bringing Natalka online. We are very content with the pace of the ramp-up and look forward to the achievement of the full capacity shortly. The Natalka operations will contribute to Polyus’ targeted increase in overall gold production to 2.8 million ounces in 2019.”

Polyus is the largest gold producer in Russia and one of the top 10 gold miners globally with the lowest cost position. Based on its 2017 Ore Reserves and Mineral Resources, the Polyus group ranks second by attributable gold reserves and gold resources among the world’s largest gold mining companies.The Polyus group’s principal operations are located in Krasnoyarsk, Irkutsk and Magadan regions and the Sakha Republic (Yakutia).

Natalka has a three stage gravity circuit – with no less than 52 centrifugal gravity concentrators, by far the world’s largest and with sizes up to 42 in. The recovery at stage 1 is around 72%, stage 2 5% and stage 3 around 1%. The screened gravity separation stage 1 concentrate will gravity flow to one of five Gekko Systems InLine Leach Reactors (ILRs), then to CIL, with the second and third gravity stages direct to CIL. Following CIL are the electrowinning and smelting steps. The three stage gravity circuit includes multiple concentractors from the two world leaders -FLSmidth’s Knelson brand and Sepro Mineral Systems’ Falcon brand. Not having flotation means no large volumes of associated reagents. The CIL circuit consists of ten agitated tanks equipped with inter-stage screens and carbon advance pumps. The CIL circuit receives reground ILR cake, combined stage 2 and 3 gravity concentrate as well as ILR cake wash solution. The CIL circuit operates at 40 wt% solids with the slurry residence time being 374 hours based on CIL tank sizing.