Kola MMC, Monchegorsk, Russia:

M. I. Ryabushkin, First Deputy General Director – Chief Engineer, e-mail: ryabushkinmi1@kolagmk.ru

Gipronikel Institute LLC, Saint Petersburg, Russia:
L. B. Tsymbulov, Director of the Research and Development Department, Doctor of Technical Sciences, e-mail: TsymbulovLB@nornik.ru
R. A. Pakhomov, Senior Researcher at the Pyrometallurgy Laboratory, Candidate of Technical Sciences, e-mail: PakhomovRA@nornik.ru
S. S. Ozerov, Lead Researcher at the Pyrometallurgy Laboratory, Candidate of Technical Sciences

The current pyrometallurgical process applied to nickel concentrate – the product of copper-nickel converter matte separation – involves the stages of thickening, filtration, fluidized-bed furnace roasting, reduction of the roasted product in tube kilns followed by separation of the resulting product into magnetic and nonmagnetic parts, as well as hydrometallurgical processing of magnetic powder and production of N-1u and N-1 grades of nickel cathodes. In spite of a rather high metallization degree of the nickel powder, which is subjected to chlorine leaching, there are certain aspects of the process that require further analysis and optimization. For example, a recent trend is a significantly higher concentration of carbon in the flotation tailings resulting from flotation of left-over hydrometallurgically processed powder, which cannot be attributed to high metallization and dissolution degree only. The process that leads to the formation of metallic conglomerates in tube kilns requires further study and can be a potential area of optimization with regard to nickel concentrate processing. The aim of the conducted experiments is to analyze the performance of fluidizedbed furnaces and tube kilns and define the best parameters. Minimum requirements were defined for obtaining high-quality powder under laboratory conditions. The authors looked at such parameters as dwelling time, consumption of reducing agent and conglomeration. The final section of this paper provides recommendations to reduce the carbon component in the final product while maintaining the reached metallization degree. It also provides guidelines for lowering the output of reduced sintered mass after the tube kiln.

1. Tsemekhman L. Sh., Fomichev V. B., Ertseva L. N. et al. Atlas of mineral raw materials, technological industrial products and marketable products of the Polar Division OJSC MMC “Norilsk Nickel”. Moscow : “Ore and Metals” Publishing House, 2010. 336 p.
2. Popov V. A., Ryabushkin M. I., Pakhomov R. A., Tsemekhman L. Sh. Thermodynamic modeling of oxidative roasting of nickel concentrate from matte separation in fluidized layer furnaces. Tsvetnye Metally. 2022. No. 4. pp. 20–26. DOI: 10.17580/tsm.2022.04.02.
3. Seregin P. S. Full-scale testing of fuel oil used as a reducing agent in the Severonickel tube kilns. St. Petersburg : OOO “Institut Gipronikel”, 2009. 9 p.
4. Seregin P. S. Full-scale testing of low-caking coal from the Kuznetsk Coal Basin used as a reducing agent in the Severonickel tube kilns. St. Petersburg : OOO “Institut Gipronikel”, 2009. 23 p.
5. Seregin P. S. Full-scale testing of low-ash coal of the Bachatsky Coal Mine (Kuzbassrazrezugol OJSC) in the Severonickel tube kilns. St. Petersburg : OOO “Institut Gipronikel”, 2009. 20 p.
6. Seregin P. S. Full-scale testing of anthracite (Gukovugol OJSC) used as a reducing agent in the Severonickel tube kilns. St. Petersburg : OOO “Institut Gipronikel”, 2009. 15 p.
7. Seregin P. S. Full-scale testing aimed at streamlining the production of active fraction of nickel powder in the Severonickel tube kilns. St. Petersburg : OOO “Institut Gipronikel”, 2009. 13 p.
8. Demidov K. A., Besedovskiy S. G., Kozyrev V. F., Tsemekhman L. Sh., Seregin P. S. et al. Method of obtaining active nickel powder. Patent RF, No. 2359049. Applied: 18.06.2007. Published: 20.06.2009. Bulletin No. 17.
9. Tsapah S. L., Demidov K. A., Khomchenko O. A., Sadovskaya G. I. Mechanism of processing of copper-nickel matte concerning chlorine based on technology of electrolytic nickel production. Tsvetnye Metally. 2009. No. 9. pp. 72–75.
10. Khomchenko O. A., Sadovskaya G. I., Dubrovskiy V. L., Smirnov P. V., Tsapakh S. L. Development and implementation of chlorine technology of nickel and cobalt at JSC “Kola MMC”. Tsvetnye Metally. 2014. No. 9. pp. 81–88.
11. Demidov K. A., Besedovskiy S. G., Shelestov N. A., Khomchenko O. A., Sadovskaya G. I. et al. Method of production of electrolytic nickel. Patent RF, No. 2303086. Applied: 20.02.2007. Published: 20.07.2007. Bulletin No. 20.
12. Miroevskiy G. P., Golov A. N., Ermakov I. G., Kozyrev V. F., Odintsov V. A. Method of electrolytic refining of nickel. Patent RF, No. 2144098. Applied: 27.05.1999. Published: 10.01.2000.
13. Ryabushkin M. I., Pakhomov R. A., Tsymbulov L. B., Savinova Yu. A. Behaviour of SiO₂ during a new process applied to nickel concentrate from matte separation at Kola MMC. Tsvetnye Metally. 2021. No. 12. pp. 14–24. DOI: 10.17580/tsm.2021.12.02.
14. Zorya V. N., Anikin A. E., Volynkina E. P., Fedyakina A. N. Understanding the beneficiation of waste accumulated at the EVRAZ ZSMK tailings pond by magnetic separation. Proceedings of the 4^th International Conference: Waste Management as the Basis for Restoring the Ecological Balance of Russia’s Industrial Areas. 23–25 October 2012, Novokuznetsk. pp. 190–198.
15. Khudyakov S. G., Melkomukova O. G., Lanovetskiy S. V. Assessing the processability of titanium plant waste by mechanical and magnetic separation. Molodezhnaya nauka v razvitii regionov. 2018. Vol. 1. pp. 230–234.
16. Zubarev A. I. An experimental study of magnetic induction and prospective beneficiation of granular manganese-containing waste by dry magnetic separation. Research papers of Donetsk National Technical University. Series: Mining and Geology. 2014. No. 2. pp. 55–59.
17. Diakonov O. M. Processing of metal-containing slurries. Lite i Metallurgiya. 2001. No. 3. pp. 181–185.
18. Zhao Q., Xue J., Chen W. Zero-waste recycling method for nickel leaching residue by direct reduction – magnetic separation process and ceramsite preparation. Transactions of the Indian Institute of Metals. 2019. Vol. 72. pp. 1075– 1085.
19. Zhao Q., Wei J. Zero-waste recycling method for textile dyeing sludge by magnetizing roasting – magnetic separation process and ceramic filter preparation. Chemical Papers. 2020. Vol. 74. pp. 4389–4399.
20. Shiryaev A. A., Velichko Yu. V., Botvinnikov V. V., Goncharov A. I. Beneficiation of the Krivoy Rog waste high-grade oxidized ores by dry magnetic separation. Obogashchenie Rud. 2005. No. 2. pp. 7–10.
21. Jeangros Q., Hansen T. W., Wagner J. B., Damsgaard C. D., Dunin-Borkowski R. E. et al. Reduction of nickel oxide particles by hydrogen studied in an environmental TEM. Journal of Materials Science. 2013. No. 48. pp. 2893–2907.
22. Manukyan Kh. V., Avetisyan A. G., Shuck Ch. E., Chatilyan H. A. et al. Nickel oxide reduction by hydrogen: kinetics and structural transformations. The Journal of Physical Chemistry C. 2015. Vol. 28. pp. 16131–16138.
23. Dong Soo Lee, Dong Joon Min. A kinetics of hydrogen reduction of nickel oxide at moderate temperature. Springer, Metals and Materials International. 2019. Vol. 25. pp. 982–990.
24. Quiroz Cabascango V. E., Bazhin V. Yu. Nickel oxide reduction in CO/CO₂ gas mixtures in reverberatory furnaces. Journal of Physics: Conference Series. 2020. Vol. 1515. 022028.
25. Mamyan S., Chatilyan H. A., Kharatyan S. L. Kinetic features of nickel oxide reduction by methane at non isothermal conditions. XV International Symposium on Self-Propagating High-Temperature Synthesis, Moscow. 2019. pp. 254–256.
26. Ryabushkin M. I., Romanov A. L., Pakhomov R. A., Tsymbulov L. B. Magnetic Separation as part of new nickel concentrate processing technology at Kola MMC: Performance Analysis and Upgrade. Part I. Tsvetnye Metally. 2022. No. 3. pp. 60–68. DOI: 10.17580/tsm.2022.03.07.
27. Ryabushkin M. I., Romanov A. L., Pakhomov R. A., Tsymbulov L. B. Magnetic separation as part of new nickel concentrate processing technology at Kola MMC: Performance analysis and upgrade. Part II. Tsvetnye Metally. 2022. No. 4. pp. 12–19. DOI: 10.17580/tsm.2022.04.01.
28. Mastryukov B. S. Engineering of metallurgical furnaces. Theory, design and engineering of metallurgical furnaces. Vol. 2. Moscow : Metallurgiya, 1986. 272 p.
29. Krishtal M. M., Yasnikov I. S., Polunin V. I., Filatov A. M., Ulianinkov A. G. Scanning electron microscopy and X-ray microanalysis: Examples of practical application. Moscow : Tekhnosfera, 2009. 208 p.
30. Savinova Yu. A., Rumyantsev D. V., Mishina O. Yu., Bannikova S. A., Somov P. A. Use of scanning electron/ion microscopy and X-ray microanalysis to examine the material composition and morphology of fine-dispersed metallurgical dusts. Proceedings of the 28^th Russian Conference on Electron Microscopy. 5–10 September 2020. Chernogolovka. pp. 110–111.
31. Savinova Yu. A. Developing an oxidizing roasting process for processing of sulphide ore concentrates of non-ferrous metals in fluidized-bed furnaces: Candidate of Technical Sciences dissertation: Saint Petersburg, 2018. 155 p.