REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):

Demidov I. V., Researcher, dvsmallville@gmail.com
Dmitriev S. V., Chief Specialist, dmitriev_sv@npk-mt.spb.ru
Mezenin A. O., Chief Specialist, Candidate of Engineering Sciences, mezenin_ao@npk-mt.spb.ru

Peter the Great St. Petersburg Polytechnic University (St. Petersburg, Russia):

Ivanov K. S., Leading Engineer, Candidate of Engineering Sciences, ivanoff.k.s@gmail.com

This paper presents a mathematical model of the dynamics of a fluidized bed of a granular material that enables an effective computational assessment of the mineral separation dynamics in force fields. The expedience of such approaches to separation is due to a number of factors, including various economic and environmental aspects, as they aim to eliminate the use of water as a dispersion medium in separation processes. The model presented in the paper is based on the assumption of a low content of magnetic or conductive particles in the material. For the convenience of mathematical modeling, two problems are considered: that of vibrational fluidization of a layer of a granular material and that of the dynamics of a separate particle being recovered (under the action of a force field). This separation seems acceptable since the proportion of recoverable particles in the source material is generally rather small and, therefore, the atypical motion of these particles has little effect on the overall fluidized gas dynamics. As part of the study of dry concentration methods, the process of extracting the unburned material from the fly ash of thermal power plants by magnetic and electrostatic separation was considered. As a result, a qualitative correspondence of the granular material dynamics was established, when under vibration, for the mathematical model presented. The work is currently underway to quantify the results, which requires an assessment of the characteristics of the force fields in the working elements of the simulated machines.
The work was performed with the financial aid of the Ministry of Science and Higher Education under Grant Agreement No. 14.585.21.0007, RFMEFI 58516X0007.

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