Empress Catherine II Saint Petersburg Mining University (Saint Petersburg, Russia)
Romashev A. O., Associate Professor, Candidate of Engineering Sciences, Associate Professor, romashev_ao@pers.spmi.ru
Balashov A. O., Postgraduate Student, s191182@stud.spmi.ru
Gatiatullin B. L., Postgraduate Student, Gatiatullin_BL@pers.spmi.ru
Nikolaeva N. V., Associate Professor, Candidate of Engineering Sciences, Associate Professor, Nikolaeva_NV@pers.spmi.ru

This article provides a detailed analysis of vibrational segregation during dry screening of carbonaceous shungite-type rocks. The study focuses on how vibration exposure time, material layer thickness, and structure affect screening efficiency and particle size distribution. An indicator quantifying the degree of segregation within the material layer is proposed and validated to assess material redistribution under varying conditions. The research combined discrete element method (DEM) numerical modeling with experimental verification using a custom setup, revealing nonlinear dependencies between process parameters and the recovery of target particle classes into lower layers. The DEM model identified key kinetic patterns governing particle dynamics within the layer. In the second stage of the study, the impact of layer thickness on target particle redistribution was examined. A robust quadratic relationship was established linking vibration duration, layer thickness, and the segregation indicator. Experimental screening confirmed that optimizing feed layer structure can enhance process efficiency. Depending on the segregation indicator, recovery of the target size fraction in the undersize product increased from 2.59 % to 7.2 %. Accordingly, a correction factor is proposed for screening models to incorporate efficiency improvements achievable through feed pre-structuring.
The study was carried out under grant No. 23-47-00109 issued by the Russian Science Foundation.

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