Electrochemical action on the flotation beneficiation of ordinary iron ore concentrate

One of the main challenges in processing fresh ferruginous quartzites is to obtain high-quality iron ore concentrates containing more than 70% total iron and less than 1.8% silica to produce DR pellets and hot Briquetted Iron (HBI). Currently, it is widely recognized that the most effective methods to achieve high-quality iron ore concentrates is through reverse flotation using cationic amine collectors in an alkaline medium. However, due to the very fine impregnation of magnetite in quartz, the insufficiently complete release of magnetite even with fine grinding, and the proximity of the flotation (surface) behavior of the separated minerals, high-quality concentrates are not always achievable in the flotation process. Consequently, exploring methods to enhance the efficiency of flotation separation of minerals and improve concentrate quality remains a pertinent issue. Historical studies have shown that electrochemical treatment can adjust the properties of reagents, enhance their effect on specific minerals, and thus control the flotation process. The efficiency of quartz and other silicates flotation by amines significantly depends on the ratio of ionic and molecular forms of the reagent in aqueous solutions of the collector and in the flotation pulp. Altering this ratio can impact the outcomes of reverse cationic flotation of iron ores. It is feasible to change the ratio of the amine forms through electrochemical oxidation or reduction of the reagent solution. Moreover, the electrochemical treatment facilitates the dispersion of the amine in the aqueous medium and its physical adsorption on minerals. Therefore, electrochemical pretreatment of amines can be considered a promising method for intensifying the reverse flotation of iron ore. This paper presents research results aimed at improving the quality of the oversize of the fine screening of ordinary magnetite concentrate from Mikhailovsky GOK, named after A.V. Varichev, through the use of electrochemically treated solutions of cationic amine class collectors in the process of reverse cationic flotation. The research findings confirmed the feasibility of using preliminary diaphragmless electrochemical treatment of reagents Tomamine RA-14 and Lilaflot 811M (esters of monoamine of different composition) for the targeted modification of their properties and for increasing the efficiency of reverse flotation. Consequently, the silica content in the flotation cell product decreased from 1.66–1.7% to 1.51–1.56, with the grade of total iron exceeding 70%.

1. Varichev A.V., Kretov S.I., Kuzin V.F. Large-scale iron ore production in the Russian Federation. Under the scientific ed. of В. F. Kuzin. Moscow: MGGU Publishing House; 2010. 395 p. (In Russ.)

2. Ismagilov R.I., Kozub A.V., Gridasov I.N., Shelepov E.V. Case study: advanced solutions applied by JSC Andrei Varichev Mikhailovsky GOK to improve ferruginous quartzite concentration performance. Russian Mining Industry. 2020;(4):98–103. (In Russ.) https://doi.org/10.30686/1609–9192-2020-4-98-103

3. Ismagilov R.I., Chanturiya E.L., Shekhirev D.V. Prognostical assessment of technological indicators of ferruginous quartzites enrichment. Sustainable Development of Mountain Territories. 2022;14(4):529–545. (In Russ.) https://doi.org/10.21177/1998-4502-2022-14-4-529-545

4. Ismagilov R.I., Chanturiya E.L., Shelepov E.V. et al. Innovative technology of magnetite concentrate processing for DRI pellets production at JSC “Mikhailovsky GOK named after A.V. Varichev”. In: Proceedings of the international conference “Current problems of complex and deep processing of mineral raw materials of natural and anthropogenic origin” Readings from Plaksin-2022. Vladivostok: DFU Publ; 2022. Pp. 5–14. (In Russ.)

5. Nikolaeva N.V., Aleksandrova T.N., Afanasova A., Chanturiya E.L. Mineral and technological features of magnetite-hematite ores and their influence on the choice of processing technology. ACS Omega. 2021;6(13):9077–9085. https://doi.org/10.1021/acsomega.1c00129

6. Ismagilov R.I., Chanturiya E.L., Shekhirev D.V., Rakhimov Kh.K. Experimental evaluation of the efficiency of cationic collectors in reverse flotation of the oversize of fine screening of ordinary magnetite concentrate from Named after A.V. Varichev Mikhailovsky GOK. In: Current problems of complex and deep processing of natural and non-traditional mineral raw materials. Proceedings of the International Conference (Readings from Plaksin – 2023). Moscow: Sputnik+ Publishing House; 2023. Pp. 251–254. (In Russ.)

7. Araujo A.C., Vianna P.R.M., Peres A.E.C. Reagents in iron ores flotation. Minerals Engineering. 2005;18(2):219–224. https://doi.org/10.1016/j.mineng.2004.08.023

8. Papini R.M., Brandão P.R.G., Peres A.E.C. Cationic flotation of iron ores: amine characterisation and performance. Minerals & Metallurgical Processing. 2001;18:5–9. https://doi.org/10.1007/BF03402863

9. Vieira A.M., Peres A.E.C. The effect of amine type, pH, and size range in the flotation of quartz. Minerals Engineering. 2007;20(10):1008–1013. https://doi.org/10.1016/j.mineng.2007.03.013

10. Ma X., Marques M., Gontijo C. Comparative studies of reverse cationic /anionic flotation of Vale iron ore. International Journal of Mineral Processing. 2011;100(3–4):179–183. https://doi.org/10.1016/j.minpro.2011.07.001

11. Lima N.P.,Valadão G.E.S., Peres A.E.C. Effect of amine and starch dosages on the reverse cationic flotation of an iron ore. Minerals Engineering. 2013;45:180–184. https://doi.org/10.1016/j.mineng.2013.03.001

12. Filippov L.O., Severov V.V., Filippova I.V. An overview of the benefication of iron ores via reverse cationic flotation. International Journal of Mineral Processing. 2014;127:62–69. https://doi.org/10.1016/j.minpro.2014.01.002

13. Nakhaei F., Irannajad M. Reagent types in flotation of iron oxide minerals: A review. Mineral Processing and Extractive Metallurgy Review. 2018;39(2):89–124. https://doi.org/10.1080/08827508.2017.1391245

14. Filippov L.O., Filippova I.V., Severov V.V. The use of collector’s mixture in the reverse cationic flotation of magnetite ore: the role of Fe-bearing silicates. Minerals Engineering. 2010;23(2):91–98. https://doi.org/10.1016/j.mineng.2009.10.007

15. Filippov L.O., Duverger A., Filippova I.V., Kasaini H., Thiry J. Selective flotation of silicates and Ca-bearing minerals: the role of non-ionic reagent on cationic flotation. Minerals Engineering. 2012;36–38:314–323. https://doi.org/10.1016/j.mineng.2012.07.013

16. Chanturiya V.A., Nazarova G.N. Electrochemical technology in hydrometallurgical beneficiation processes. Moscow: Nauka Publ.; 1977. 160 p. (In Russ.)

17. Chanturiya V.A., Dmitrieva G.M., Trofimova E.A. Intensification of beneficiation of iron ores of complex material composition. Moscow: Nauka Publ.; 1988. 206 p. (In Russ.)

18. Ryaboy V.I. Cationic reagents. In: Physico-chemical fundamentals of flotation theory. Moscow: Nauka Publ.; 1983. Pp. 167–181. (In Russ.)