Effect of particle size distribution on screening efficiency of vibrating screen

Vibrating screen screening efficiency is affected by a variety of factors, among which particle size distribution (PSD) has long been neglected by researchers. In order to reveal the actual influence of PSD on screening efficiency, this paper systematically explores the mechanism of PSD on the screening efficiency of vibrating screen based on discrete element method simulation. Based on the relative sieve hole size of the particles, the feed particles are classified into three categories: permeable sieve particles, refractory sieve particles and obstructive particles. The simulation results show that obstructive particles significantly enhance the screening efficiency, while refractory sieve particles have an inhibitory effect and permeable sieve particles have a small effect. It was found that the probability of various types of particles passing through the sieve is basically stable under different PSD conditions, and then constructed a sieve efficiency prediction model based on the content of particles and the probability of passing through the sieve, and the prediction results are highly consistent with the simulation data, and the prediction error is controlled within ± 5%. In addition, the double-deck vibrating screen exhibited higher screening efficiency and stability under complex PSD conditions, outperforming the single-deck structure in 96.6% of the experimental groups. The research results provide a theoretical basis for the optimization of vibrating screen process parameters and structural design.