EXTRACTION OF MINERAL RAW MATERIALS OF A GIVEN SIZE AND DENSITY FROM ROCK MASS BY THE VIBRATION METHOD

Abstract

Vibration processes are widely used in technology in the processing of bulk materials to improve the efficiency of such operations as transportation, mixing, separation by size and material composition and compaction. Theoretical studies of the processes of vibration displacement of particles in granular media under the influence of vibration are presented by a large number of mathematical models, but many of them need to be compared with experimental data. Practical interest is the determination of the time of ascent of relatively large or densest particles to the surface of a layer of crushed rock mass under the action of the vertical vibration component. The article presents the results of an experimental study of this process. A set of experiments on the extraction of basalt particles from tuff rock mass (waste from basalt quarries), ferruginous quartzites from the mass of dump rock, and relatively large granite particles from crushed granite mass was performed. Processing of the experiments using the SPSS Statistics program allowed us to analyze the process and obtain regression models for determining the time of ascent of a particle of a given size and density from the rock mass, including two generalized regression models. In the first of them, the variables were the amplitude and frequency of vibration, the particle size of the medium was 25 mm, the particle density of the medium was 1.6-2.8 g/cm3, the particles floating under the action of vibration have a particle size of 50 mm, their density varies from 2.5 to 5.1 g/cm3. In the second model for А= 5 мм, w=30 Гц, an additional variable factor is the size of the floating particle, which varies from 50 to 25 mm The resulting equations allow us to determine the time of ascent and predict the extraction of particles of a given size and density under the influence of vibration, for example on the conveyor belt, without conducting cumbersome experiments.