Enhancement of Fine Wet Ore Screening Efficiency

Introduction. Particle size classification of crushed ore is one of the key operations in the preparation of raw materials for metallurgical processing. The application of fine wet screening of ore pulp has enabled an increase in the concentration of valuable components in the processed products.Problem Statement. The viscosity of ore pulp, caused by the presence of solid-phase particles and their aggregates of different sizes and densities, has reduced the rate at which particles pass through the screen apertures, thereby decreasing the effi ciency of the screening process.Purpose. To determine the effect of ultrasonic treatment on the dynamic viscosity of ore pulp and on the frictional interaction between crushed ore particles in order to improve the productivity and efficiency of fine wet screening.Materials and Methods. The study has employed a combination of research methods, including thegeneralization of scientific information, analysis of particle interactions and acting forces during the screening process, mathematical and computer modeling, as well as experimental investigations. Results. Under the influence of ultrasonic vibrations, additional forces have been generated in the ore pulp that act on solid-phase particles and gas bubbles. The most significant among them have been identified as the ultrasonic radiation pressure force and the pressure waves generated by cavitation collapse of gas bubbles. The obtained results have demonstrated that the application of ultrasonic treatment to the screen feed results in increasing the screening efficiency by 2—3%.Conclusions. The proposed method for improving the efficiency of material separation by particle size, based on the introduction of ultrasonic vibrations of a specified amplitude and frequency into the feed material, has increased the mobility of crushed ore particles in the pulp, reduced interparticle adhesion forces, and created favorable conditions for cavitation effects and the destruction of heterophase aggregates. As a result, the quality of classification and the overall screening performance have been improved.