Ural State Mining University (Ekaterinburg, Russia):

A. E. Pelevin, Dr. Eng., Prof., Dept. of Mineral Processing, e-mail: a-pelevin@yandex.ru

The possibility of applying dressing in an alternating magnetic field for the stage separation of iron concentrate before the last stage of grinding is considered in order to reduce the cost of grinding or increase the technological indicators of titanomagnetite ore beneficiation. Stage separation of the concentrate is possible when using magnetic separation in an alternating field with frequencies of 120–160 Hz. The mass fraction of iron in the concentrate isolated before the last stage of grinding was 61.51–63.12%. Reduction in the frequency of the alternating magnetic field to 40–80 Hz did not allow to obtain a concentrate of the required quality. The use of magnetic separation with an alternating magnetic field at a frequency of 120 Hz, compared with the standard beneficiation scheme, allows to increase the yield of concentrate by 0.17% and extraction of iron in concentrate by 0.65% with the same mass fraction of iron in concentrate. Increasing the frequency of the alternating magnetic field to 160 Hz allows to increase the mass fraction of iron in the concentrate by 0.92% and extraction of iron in the concentrate by 0.63% while reducing the yield of the concentrate by 0.1%. The yield of concentrate isolated before the last stage of grinding should not exceed 43-53%. Increasing the yield of the concentrate can lead to a significant decrease in the mass fraction of iron in the concentrate. The use of a scheme with the gradual separation of the concentrate leads to a decrease in the load on the last stage of grinding and to an increase in the size of the produced concentrate. This indicates the possibility of reducing the concentrate production cost by decreasing the volume of grinding equipment on the last stage.

1. Palaniandy S., Halomoan R., Ishikawa H. TowerMill circuit performance in the magnetite grinding circuit – The multi-component approach. Minerals Engineering. 2019. Vol. 133. pp. 10–18.
2. Markauskas D., Kruggel-Emden H. Coupled DEM-SPH simulations of wet continuous screening. Advanced Powder Technology. 2019. Vol. 30, Iss. 12. pp. 2997–3009.
3. Nemykin S. А., Kopanev S. N., Mezentsev Е. V., Okunev S. М. Iron concentrate production with the increased content of useful component. Gornyi Zhurnal. 2017. No. 5. pp. 27–31.
4. Ismagilov R. I., Kozub А. V., Gridasov I. N., Shelepov E. V. Modern directions of increasing the efficiency of processing of ferrous quartzites on the example of JSC Mikhailovsky GOK named after A. V. Varichev. Gornaya promyshlennost. 2020. No. 4. pp. 98–103.
5. Matiolo E., Couto H. J. B., Lima N., Silva K., Freitas A. S. Improving recovery of iron using column flotation of iron ore slimes. Minerals Engineering. 2020. Vol. 158. pp. 106608.
6. Pattanaik A., Rayasam V. Analysis of reverse cationic iron ore fines flotation using RSM-Doptimal design – An approach towards sustainability. Advanced Powder Technology. 2018. Vol. 29, Iss. 12. pp. 3404–3414.
7. Liamas-Bueno M., Lopez-Valdivieso A., Corona-Arroyo M. A. On the mechanisms of silica (SiO₂) recovery in magnetite ore low-magnetic-drum concentration. Mining, Metallurgy and Exploration. 2019. Vol. 36. pp. 131–138.
8. Pelevin А. Е. Improving magnetite concentrate quality in alternating field. Obogashchenie Rud. 2019. No. 6. pp. 19–24.
9. Osipova N. V. Model for optimal control of a magnetic separator based on the Bellman dynamic programming method. Chernye Metally. 2020. No. 7. pp. 9–13.
10. Osipova N. V. Automatic control system for wet magnetic separation of iron ore. Gornyi Zhurnal. 2019. No. 1. pp. 62–65.
11. Osipova N. V. Use of the Kalman filter at automatic control of indicators of magnetic beneficiation of iron ores. Izvestiya vysshikh uchebnykh zavedeniy. Chernaya metallurgiya. 2018. Vol. 61, No. 5. pp. 372–377.
12. Vaysberg L. А., Korovnikov А. N. Fine screening as an alternative to hydraulic size classification. Obogashchenie Rud. 2004. No. 3. pp. 23–34.
13. Rosario P. P. Technical and economic assessment of a non-conventional HPGR circuit. Minerals Engineering. 2017. Vol. 103–104. pp. 102–111.
14. Rocha D., Spiller E., Taylor P., Miller H. Predicting the product particle size distribution from a laboratory vertical stirred mill. Minerals Engineering. 2018. Vol. 129. pp. 85–92.
15. Prokopyev S. А., Pelevin А. Е., Napolskikh S. А., Gelbing R. А. Staged screw separation of magnetite concentrate. Obogashchenie Rud. 2018. No. 4. pp. 28–33.
16. Pelevin А. Е., Sytykh N. А. Iron concentrate stage separation by means of drum magnetic separator with modified separating bath. Obogashchenie Rud. 2016. No. 4. pp. 10–15.
17. Karmazin V. V., Andreev V. G., Palin I. V., Zhilin S. N., Pozharskiy Yu. М. Development of equipment for the technology of full-stage beneficiation of magnetite quartzite. Gornyi Zhurnal. 2010. No. 12. pp. 85–89.
18. Karmazin V. V., Sinelnikova N. G., Loginova L. А., Eputaev G. А., Danilova М. G. Study of the stage separation process in separators with a magnetic system having magnets of different heights. Gornyi informatsionno-analiticheskiy byulleten. 2007. No. 9. pp. 310–315.
19. Opalev А. S., Biryukov V. V., Shcherbakov А. V. Stage separation of magnetite concentrate at development of energy-saving technology for ferrous quartzites beneficiation at JSC Olkon. Gornyi informatsionno-analiticheskiy byulleten. 2015. No. 11. pp. 60–62.
20. Khokhulya М. S., Opalev А. S., Rukhlenko Е. D., Fomin А. V. Obtaining magnetite-hematite concentrate from ferrous quartzites and stored wastes of their beneficiation on the basis of mineralogical and technological research. Gornyi informatsionno-analiticheskiy byulleten. 2017. No. 4. pp. 259–271.
21. Zhou J.-F., Zhang S., Tian F., Shao Ch.-L. Simulation of oscillation of magnetic particles in 3D microchannel flow subjected to alternating gradient magnetic field. Journal of Magnetism and Magnetic Materials. 2019. Vol. 473. pp. 32–41.