Zabaykalsky State University, Chita, Russia:

V. G. Cherkasov, Professor, Doctor of Technical Sciences, Assistant Professor, e-mail: cherkasov1948@yandex.ru
L. V. Shumilova, Professor, Doctor of Technical Sciences, Assistant Professor

The technical solution for the thin-layer apparatus structures’ use in technological processes of polymineral sands enrichment as applied to alluvial deposits development is considered. Characteristic features of technological processes at sand washing, requirements to the equipment in mobile variant and comparative estimation of possibilities on typical thin-layer analogues’ use in extreme operating conditions of enrichment complexes of washing devices type are given. It is shown that massproduced thin-layer devices do not meet the specific requirements both in weight and dimensions and in absence of enrichment features to capture small and thin classes of valuable component from the resulting suspension flow. Proposed new technical solution of the apparatus on the basis of large diameter pipes has allowed to reduce the total weight and dimensions of the structure many times, which gave them a transportability factor with frequent change of washing locations. The adopted longitudinal configuration of the device makes it possible to set the double-thin-layer effect of separation of the suspension’s two-phase medium, which is used to form an enrichment function. Testing of prototypes in the production environment has shown that the use of hardware design process of water treatment based on the proposed thin-layer devices makes it possible to return 80–90% of process water to the turnover, bypassing the environmentally unstable groundwater sediment ponds. Physical modeling has shown that the design with two-contour flows of sediment layer additionally forms the effect of particle segregation with the subsequent lower part of the localized sludge cutting off. At the same time the technological efficiency of heavy fractions’ enrichment is provided up to 79,1% according to Hancock-Luiken formula.

1. Zamyatin О. V. Processing of gold-bearing sands at sluices. Basic laws and technological possibilities of the process. Zolotodobycha. Irkutsk : JSC "Irgiredmet", 2012. No. 169. Available at: https://zolotodb.ru/articles/technical/10789 (accessed: 15.10.2020).
2. Lunyashin P. D. Problems of Russian placers and ways to solve them. Zoloto i tekhnologii. 2018. No. 2. pp. 60–65.
3. Bauman А. V. Thin-layer settlers. Plate thickeners and blocks. Novosibirsk : Gormasheksport, 2014. 18 p.
4. Pryanichnikov Е. V., Shcherbakov О. К., Gorelykh А. S. Determination of some design and technological parameters of thin-film thickeners. Obogashchenie Rud. 1985. No. 2. pp. 23–26.
5. Lopez J. S., Burgos A. J., Rodriguez P. U. Lamella settling (FS-PRI-004). Universidade da coruna : INDITEX. Spain, 2013. 29 p.
6. Kowalski P. W. The method of calculations of the sedimentation efficiency in tanks with lamella packets. Archives of Hydro-Engineering and Environmental Mechanics. 2004. Vol. 51, No. 4. pp. 371–385.
7. Vempati B., Oztekin A., Neti S. Stability of two-layered fluid flows in an inclined channel. Acta Mechanica. 2010. Vol. 209. pp. 187–199.
8. Barmak I., Gelfgat A., Vitoshkin H., Ullmann A. et al. Stability of stratified two-phase flows in horizontal channels. Physics of Fluids. 2016. Vol. 28, Iss. 4.
9. Kremer Е. B., Nagaev R. F., Pryanichnikov Е. V. et. al. Hydrodynamics of thin-film thickeners and principles of their design. Obogashchenie Rud. 1985. No. 3. pp. 27–31.
10. Bauman А. V. Thin-layer thickener efficiency estimation method. Obogashchenie Rud. 2015. No. 2. pp. 36–41.
11. Cherkasov V. G. Design solutions for the formation of the double separation effect in thin-film (channel) devices. Gornyy informatsionnoanaliticheskiy byulleten. 2006. No. 2. pp. 379–384.
12. Cherkasov V. G., Myazin V. P., Makkaveev E. P., Shevchenko Yu. S. Thin-film separator of mineral particles in the flow. Patent RF, No. 1692028. Published: 27.06.1995.
13. Cherkasov V. G., Balandin O. A., Myazin V. P. Thin-film separator of mineral particles. Patent RF, No. 2248848. Published: 27.03.2005.
14. Cherkasov V. G., Silinskiy V. S., Tsydapova O. S., Veretelnikova A. V. Thin-layer separator of polymineral hydraulic suspension. Patent RF, No. 2385771. Published:10.04.2010.
15. Myazin V. P., Cherkasov V. G. Principles of localization of water circulation at washing of metal-bearing sands by transport and processing complexes. Gornyy informatsionno-analiticheskiy byulleten. 2007. No. 1. pp. 360–366.
16. Cherkasov V. G. Increasing the functional capabilities of thin-layer (channel) apparatuses in beneficiation processes. Obogashchenie Rud. 2017. No. 5. pp. 42–47.
17. Khatkova A. N., Cherkasov V. G. Formation of a double thin-layer effect in flow-type devices during processing of a polymineral hydraulic mixture. Vestnik Zabaykalskogo gosudarstvennogo universiteta. 2019. Vol. 25. No. 7. pp. 84–90.
18. Boronin S. А. Hydrodynamic stability of the stratified flow of the suspension in a flat channel. Doklady akademii nauk. 2009. Vol. 429, No. 4. pp. 477–480.
19. Kushnir R., Segal V., Ullmann A., Brauner N. Inclined two-layered stratified channel flows: Long wave stability analysis of multiple solution regions. Int. J. Multiphase Flow. 2014. Vol. 62. pp. 17–29.