LLC “Institute “Gipronikel”, Saint Petersburg, Russia:

V. A. Zinovev, Former Member
M. I. Kalashnikova, Head of Laboratory of Hydrometallurgy
Yu. N. Lisakov, Senior Researcher, e-mail: jnlis@nickel.spb.ru
Yu. M. Pelikh, Head of Group

Integrated-laboratory and industrial tests of Hastelloy-type materials were carried out in corrosion/erosion wear during pressure autoclave oxidative leaching of nickel-pyrrhotite concentrates at Nadezhda Metallurgical Plant. The carried out ultrasonic and X-ray inspection of Hastelloy G-35 alloy samples has shown the absence of any discarded defects both in original samples, and in corrosion-tested samples. The carried-out complex of metallography researches has shown the high resistance of this alloy to corrosion-erosion wear and its disinclination to intercrystalline corrosion. At the same time, the currently-applied alloy 06KhN28MDT (06ХН28МДТ) is subjected to corrosion. The expected life of Hastelloy G-35 alloy products is increased by not less than 15–20 times (in comparison with existing products, made of 06KhN28MDT alloy). The carried out researches point that this alloy is also resistant during processing of other types of ore raw materials in the similar conditions. Taking into account the modern global trends to expansion of application of hydrometallurgical methods from ore raw material opening to refining and affinage of metals, results of this work can be useful during the choice of materials for various hydrometallurgical products, and during the design of apparatuses for realization of these processes.

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