Discharge of Size-Segregated Powders from a 2D-aerated Silo

Abstract

The effects of aeration on the discharge of silos loaded with initially segregated particles have been evaluated. Experiments were carried out on a two-dimensional laboratory-scale aerated silo, loaded according to either ideal or controlled natural segregation patterns. Two different systems of powders made up of two size cuts were tested, one system belonging to group A and the other to group B of the Geldart classification. One of the two cuts was colored to visualize the segregation changes and the solids flow during discharge. Time variations of the discharged solids discharged were evaluated by means of a rotating sample. Results of aerated discharge were compared with mass flow discharge. From analysis of the experimental results, it is possible to conclude that aerated discharges can effectively promote the uniform solids discharge of horizontally segregated solids of group A powders. In contrast, further segregation occurs for aerated discharges of group B powders below the minimum for fluidization.

Keywords

• silodischarge
• aerated powders
• segregation
• mixing