Gipronikel Institute LLC, Saint Petersburg, Russia:

V. A. Popov, Lead Researcher at the Pyrometallurgical Laboratory, Candidate of Technical Sciences

R. A. Pakhomov, Senior Researcher at the Pyrometallurgical Laboratory, Candidate of Technical Sciences, e-mail: pakhomovra@nornik.ru

Kola MMC, Monchegorsk, Russia:
M. I. Ryabushkin, First Deputy General Director – Chief Engineer, e-mail: RyabushkinMI1@kolagmk.ru

Saint Petersburg, Russia:
L. Sh. Tsemekhman, Editorial Board Member at Tsvetnye Metally, Doctor of Technical Sciences, Professor3, e-mail: lev.tsem1@gmail.com

Processes of oxidative roasting of sulfide concentrates in fluidized bed furnaces are quite widely used in sulfide copper, copper-nickel and pyrite concentrates processing. After roasting, the calcine is usually either smelted or hydrometallurgically processed. The results of various laboratory studies and industrial practice of sulphide roasting published in literature. This article will focus on thermodynamic modeling of roasting of nickel concentrate from matte separation. By means of FactSage software thermodynamic modeling of oxidative roasting of nickel concentrate from matte separation has been performed within the temperature range of 300–1200 ^оC and lg p_O2 range from -20 to -2. Areas of possible calcined products – sulfates, oxides, sulfides and metallic non-ferrous metals shown. According to calculation results, formation of sulfates of non-ferrous metals is observed in low-temperature area, the area is moving to high temperatures with an increase in the oxidizing capacity of gas phase. In the area of medium temperatures, oxide phases, including spinels, observed. Sulfide and metal phases exist at the upper limit of the investigated temperature range. Comparison of the calculation results with the research data of real calcines from fluidized bed furnaces made using SEM and EMPA methods. It is observed that processes in real furnaces can be successfully calculated based on the assumption of thermodynamic equilibrium in fluidized bed. It was determined that calculation of the oxidation process using FactSage algorithms and databases is quite correct and can be used, among other things, when implementing control systems for industrial furnaces.
The authors would like to thank director of the Research & Development Department at Gipronikel Institute Doctor of Technical Sciences L. B. Tsymbulov for providing advisory support.
The authors would like to thank Yu. A. Savinova, Candidate of Technical Sciences, senior researcher at Gipronikel Institute, for her contribution to the research work.

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