Segregation model for percolation mechanism

Segregation, as a ubiquitous and undesirable phenomenon, occurs nearly any where and any time as long as particulate materials are stored, handled, processed, or conveyed. It can cause serious issues related to powder products such as uneven quality, fluctuating packet weight, low mechanical strength of compacts and abrasives, poor refractory, and low rates of contact and reaction. The goal of this research was to study percolation and sieving segregation patterns -quantification, model development and validation of particulate materials. Herein those results pertinent to the development and validation of a percolation segregation model based on the mechanistic theory and dimensional analysis are presented. Toward this end, a mechanistic theory-based segregation model (denoted as MTB model) for binary G-g (coarse material glass beads, G and fine material glass beads, g) and F-g (coarse materials feed, F and fine material glass beads, g) combinations was developed using principles of mechanics, dimensional analysis, and linear regression methods. The MTB model successfully correlated the effect of particle size, density, and shape to segregation potential of binary mixtures in one quantitative equation. The verification results showed that the MTB model accurately (Root Mean Square Error, RMSE=1.18) predicted the segregation potential for G-g and F-g combinations with size ratios of 4:1, 6:1, and 8:1 and absolute sizes of 710, 1,000, and 1,400 micrometers. The validation results showed that the MTB model produced RMSE = 1.44 for smaller size ratios such as 3:1 and 2:1.