The grinding process plays a crucial role in many technological operations. However, the complexity of increasing product fineness and energy efficiency in particle size reduction poses a problem in grinding processes. This study proposes a new approach for increasing grinding efficiency under dry grinding conditions in mills with grinding media. The approach involves a complex impact on the particle, in which it is subjected to two- and one-sided actions by the grinding media in the horizontal and vertical directions, respectively. The efficiency of the approach was tested by mathematical modeling and experimentation. The difference between the theoretical and experimental results was less than 11%, indicating the reliability of the proposed model. The results indicate that the proposed approach enhances the grinding efficiency by nearly fourfold and can be applied in industrial sectors that require high product fineness.

Fine grinding is often associated with high energy consumption, and the choice of operating parameters has a direct effect on product fineness. This study examines dry particle size reduction under the two-sided impact of counter-moving grinding media. A previously developed calculation model was used to estimate the final particle size, and the calculated values were compared with experimental results obtained for quartz-rich river sand with an initial particle size of 100 μm. The study considered four parameters: horizontal amplitude, vertical amplitude, oscillation frequency, and grinding media diameter. Increasing the horizontal amplitude from 2 to 6 mm reduced the experimental product fineness from 19.6 to 4.8 μm. The vertical amplitude had a weaker effect, but increasing it from 1 to 4 mm also reduced the experimental particle size from 9.9 to 5.0 μm. An increase in frequency from 40 to 60 Hz reduced the experimental product fineness from 12.1 to 5.4 μm. The opposite tendency was observed for grinding media diameter: increasing it from 5 to 15 mm increased the experimental particle size from 4.8 to 11.4 μm. The average difference between theoretical and experimental results was 12.28%. In 12 of the 17 studied operating modes, the deviation was less than 15%. Laser particle size analysis of the selected finest sample was additionally performed to characterize the particle size distribution and fine particle fraction. The present work extends the previous model validation by evaluating the main operating variables and proposing a preliminary rational operating range for the studied dry grinding process. The results show that the model can be used for preliminary estimation of product fineness and for identifying the most influential operating parameters under the studied dry grinding conditions.