Study on screening process and segregation mechanism of wet sand and gravel particles based on discrete element method

Abstract

To study the screening process and explore the segregation mechanism of wet sand and gravel particles, the screening of wet particles is carried out by discrete element method. The accurate parameter settings of wet particles are obtained by parameter calibration of the cylinder lifting. Then, the distribution of wet particles shows the triangular cone and ellipsoid particles have been screened in feeding and screening area. Moreover, there is obvious splash of particles in dry screening while there is no splash in wet screening, which explains the serious dust pollution in dry screening process. Meanwhile, the number of triangular cone and ellipsoid particles in feeding and screening area in wet screening process is more than that in dry screening process, which indicates wet screening process has higher screening efficiency. By comparing the average distances of different particles to the screen surface, the segregation mechanism of different particles is obtained. Furthermore, the square of velocity trends are in good agreement with the average distances of particles, which indicates that square of velocity can also be used as the evaluation index for particle segregation. The above researches provide a reference for optimization of the wet screening process parameters.

Graphical abstract