Analysis of the screening process of particulate material and the application of a grade efficiency curve as a function of screen length

Abstract

Screening of powders is an important unit operation for industrial separation of solid particles, but to design equipment for a specific material requires considerable time and material, which encourages the use of mathematical models to predict or characterise the process. The goal is to represent the particle size separation during the process, to determine the screening efficiency using mathematical models with the fewest possible adjustable parameters. In this experimental study, a detailed analysis of the continuous screening process using multistage sampling was conducted and modified separation curve models were fitted. Well-known separation curve models were complemented by kinetic models, which became functions not only of the particle size, but also of the screen length T(x,l). These new models were successfully validated on experimental data. They provide a more complex characterisation of the process, due to the added length variable.