ALTA 2013: Pokrovskiy pressure oxidation (POX) HUB
The Russian Federation contains numerous operating gold mines; however like most of the world these mines are encountering refractory ore which requires additional pre-treatment prior to cyanidation for gold recovery. It has been reported that about 75-80% of known gold reserves in Russia are refractory or partly refractory. Petropavlovsk is the second largest gold producer in Russia with assets located in the Far East. The company currently has four open pit mines and alluvial operations and employs about 15,000 people (total group). Half of Petropavlovsk’s JORC compliant reserves are refractory. For the treatment of refractory ore from Malomir and Pioneer mine sites autoclave Pressure Oxidation (POX) has been chosen as the pre-treatment technology (after comparison with biological oxidation and roasting). Oxidised concentrate from both mine sites will be further treated in existing RIL facilities for gold recovery at Pokrovskiy.
Extensive batch autoclave testwork and flowsheet development has been completed by SRC Hydrometallurgy in St Petersburg. Pilot facilities have also been built and operated in Blagoveshchensk to support the POX design. Outotec has supplied all major equipment for both the Malomir concentrator and the Pokrovskiy POX Hub plant and continues to work assist Petropavlovsk with project implementation.
Outotec employs 4805 personnel in 25 locations around the world. Continuous technology development and innovation since the 1890’s has led to a technology and equipment portfolio that in many areas is market leader. Outotec as part of Outokumpu developed considerable knowledge and technology related to autoclave matte leaching and continues to supply autoclave technology for the leaching of nickel mattes. Recently with the design and equipment supply for the Pokrovskiy POX plant Outotec has now also provided modern pressure oxidation equipment for the treatment of sulphidic refractory gold concentrates.
Construction of the Malomir concentrator and Pokrovskiy POX plant is currently underway with commissioning of the Malomir flotation plant expected in Q3 2013 and Pokrovskiy POX plant planned for Q1 2014. The Pioneer concentrator is scheduled for future development Development and description of the Pokrovskiy POX Hub is described in this paper.