A partnership worth its weight in gold
Petropavlovsk is one of the five largest gold mining companies in Russia, with three operations named Malomir, Pioneer, and Albyn in Russia’s Far Eastern Federal District. The company supplements traditional non-refractory production with the processing of refractory concentrate.
The mining of refractory ore is becoming increasingly common in Russia’s numerous operational gold mines, with the process requiring additional pre-treatment prior to cyanidation for gold recovery.
Enabling profitable processing of challenging ore
Close to 50% of Petropavlovsk’s 21 Moz of resources and reserves are now classified as refractory. As it will be necessary for Petropavlovsk to process refractory ore in the long term, the company decided to develop and invest in a pressure oxidation (POX) hub at Pokrovskiy, where concentrates from different mines can be processed.
Petropavlovsk’s four autoclaves process in the region up to 500,000 tons of flotation concentrate per year, with this project opening up new opportunities in refractory ore processing for the Russian gold mining industry. The POX hub is in close proximity to the company’s depleted mine, Pokrovskiy, where it benefits from milling facilities, road and rail infrastructure, low-cost renewable power, and a nearby limestone deposit – a key ingredient in the POX process.
The plant was commissioned at the end of 2018, initially treating refractory gold concentrate from the Malomir mine – which accounted for 18% of Petropavlovsk’s gold production in 2018 – and third-party concentrates. In the future, the POX hub will treat concentrates from the group’s Pioneer refractory gold mine, which is one of the largest gold mines in Russia based on processing capacity.
Optimizing performance with extensive R&D
The company performed extensive research into industrial-scale POX technology, building a state-ofthe-art R&D center in St. Petersburg in 2008 and a POX pilot plant in Blagoveshchensk in 2011. Extensive batch test campaigns were conducted at the R&D center to determine the optimal process conditions and develop a POX flowsheet for different ore types. A detailed mathematical model was developed to help optimize the design of the POX process. Process performance was confirmed and the model was validated with pilot-scale experiments at the Blagoveshchensk plant, providing a solid basis for the scale-up and final plant design.