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Saint Petersburg, Russia

Pakhomov R.A.,OOO Institute Gipronikel | Starykh R.V.,Saint Petersburg State Polytechnic University
Russian Metallurgy (Metally) | Year: 2014

The laws of gas reduction of oxidized nickel ores (ONOs) are studied. The theoretical prerequisites of the selective reduction of ONO nickel, which are based on the difference between the oxygen partial pressures over the NiO-Ni and FeO-Fe systems, are discussed. The effect of the oxygen partial pressure during reducing roasting of ONOs of ferruginous and magnesia types on the reduction parameters and the quality of the ferronickel formed upon subsequent melting of cinders is experimentally investigated. The optimum conditions of preliminary gas reduction of ONOs are determined. Melting of the cinder of reducing roasting leads to the formation of nickel-rich ferronickel (20–50 wt % Ni for various types of ores) upon the extraction of nickel into ferronickel of >95%, which substantially exceeds the parameters of the existing commercial processes. © 2014, Pleiades Publishing, Ltd. Source

Kalinkin P.N.,Novosibirsk State University | Kovalenko O.N.,RAS Boreskov Institute of Catalysis | Platonov O.I.,OOO Institute Gipronikel
Catalysis in Industry | Year: 2011

Change in the activity of AO-NKZ-2 (AO-MK-2) alumina catalyst in the Claus reaction and transformations of carbonyl sulfide during operation over four years in the Claus reactor at the Magnitogorsk Metallurgical Combine's coke-oven gas purification shop were studied at an average temperature of 245-260°C and a volume velocity of ~2000 h-1. The rate constants of the Claus reactions and COS transformation were determined, and the changes in the active surface area of the catalyst were investigated. Fundamental discrepancies in the rate and deactivation mechanism of the Claus catalysts were revealed with respect to the reactions of the conversion of hydrogen sulfide and carbonyl sulfide. © Pleiades Publishing, Ltd., 2011. Source

Pigarev S.P.,OOO Institute Gipronikel | Tsymbulov L.B.,OOO Institute Gipronikel | Istomin S.A.,RAS Institute of Metallurgy | Selivanov E.N.,RAS Institute of Metallurgy | Chumarev V.M.,RAS Institute of Metallurgy
Russian Metallurgy (Metally) | Year: 2013

The viscosities of the slags that form during the continuous converting of copper mattes and concentrates into blister copper are determined. The compositions of SiO2-CaO-Al2O3-FeOx-Cu2O-NiO slag melts are varied over a wide range of (Fe + Ni) concentrations (25.5-40.2 wt %) and ratios SiO2/CaO (0.25-3.9) and (Fe)/(Cu + Ni) (0.4-1.6). The slag viscosity is measured by a vibrational method in the temperature range 1050-1450°C. The viscosity of a homogeneous melt is shown to be 0.5-2.0 P, and it increases sharply below the primary solidification temperature. © 2013 Pleiades Publishing, Ltd. Source

Tsymbulov L.B.,OOO Institute Gipronikel | Pigarev S.P.,OOO Institute Gipronikel | Selivanov E.N.,RAS Institute of Metallurgy | Chumarev V.M.,RAS Institute of Metallurgy
Russian Metallurgy (Metally) | Year: 2011

The structure and liquidus temperature of the SiO2-CaO-Al2O3-FeOx-Cu2O-NiO slags that form during continuous converting of copper mattes and concentrates into blister copper in a Vanyukov furnace used as a melting unit are studied. The slag melt compositions are varied over wide limits of the total (Fe + Ni) and (SiO2 + CaO) concentrations by changing the consumption of fluxing components. The slags are investigated by X-ray diffraction, scanning electron microscopy, and electron-probe microanalysis. The liquidus temperatures of the slags are determined by differential thermal analysis. It is found that, as the consumption of fluxing components changes, the concentration of iron-nickel spinels based on trevorite NiFe2O4 changes substantially and the forms of copper change in the slags. The results obtained are used to recommend the optimum consumption of fluxing components for the process of continuous converting. © 2011 Pleiades Publishing, Ltd. Source

Starykh R.V.,OOO Institute Gipronikel | Sineva S.I.,OOO Institute Gipronikel
Russian Metallurgy (Metally) | Year: 2012

A deep analysis and mutual fitting of the data on all ternary boundary systems have resulted in obtaining information about the phase transformations in high-sulfur Fe-Ni-S compositions and in augmentation of data on the projections of the solidus surfaces in the Fe-Ni-Cu and Fe-Ni-S systems. The studies are performed using differential thermal analysis, scanning electron microscopy, and electron-probe microanalysis. The investigation carried out is a continuation of the cycle of studies dealing with an experimental construction of the phase diagrams of the ternary systems bounding the quaternary Fe-Ni-Cu-S system. © 2012 Pleiades Publishing, Ltd. Source

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