SRC Hydrometallurgy (LLC), Saint Petersburg, Russia:

M. V. Klementiev, Deputy General Director Responsible for Project Administration and Implementation, e-mail: klementev-m@gidrometall.ru

Prospective Development Department, Petropavlovsk Management Company JSC, Moscow, Russia:
V. K. Fedorov, Head of the Prospective Development Department

Pokrovskiy Mine JSC, Tygda selo, Amur Region, Russia:
A. S. Zavalyuev, Chief Engineer at the Pokrovsky Pressure Oxidation Hub

The autoclave pressure oxidation (POX) mode of gold-bearing sulfide flotation concentrates at Pokrovskiy POX hub is characterized by high intensity. For its successful implementation agitators with increased aeration capacity were used. They were designed by Outotec company and have higher aeration capacity in comparison with the designed parameters used in Pokrovskiy POX hub project. This means that they have an excess of capacity for sulfide oxidation. Agitators were selected by technical specialists of JSC “Petropavlovsk”. The choice was based on laboratory research and pilot POX tests of gold sulfide raw materials, as well as on the theoretical calculations of this process using the comprehensive mathematical model. A necessary condition for the test and calculation results reliability is the compliance of the experimental slurry agitation with the real industrial conditions. The so-called “sulfite number” of the agitator and the mass transfer coefficient of oxygen were used as a criterion of compliance by the specialists of the SRC “Hydrometallurgy”. Agitation conditions were selected to ensure sulfite numbers of about 1,0 mol Na₂SO₃/(l·atm·h) at the stage of the laboratory and pilot tests. It is close to sulfite numbers of agitators of industrial autoclaves. Outotec company proposed an experimental demonstration of the high aeration capacity of its agitators at the equipment selection stage for an industrial autoclave. This fact was confirmed during the operation of the autoclaves at Pokrovskiy POX hub in 2019.

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