Flowability and Handling Characteristics of Bulk Solids and Powders - A Review

Abstract

Much research regarding handling and storage characteristics of bulk solids has been conducted over the years. Physical properties of granular solids play a significant role in their resulting flow and storage behavior, and are therefore essential to design appropriate, efficient, and economic bulk solids handling and storage equipment and structures. Distillers Dried Grains with Solubles (DDGS) are a bulk material that has been widely used as a protein source for ruminants and non-ruminants for more than two decades. Distillers’ grains are energy dense as they contain high fat levels. With the exponential growth of the fuel ethanol industry in the past several years, significant quantities of distiller’s grains are now being produced. To effectively utilize these feeds in the domestic market, however, these coproduct streams are increasingly being transported greater distances, and must be stored until final use. DDGS flow is often problematic as it can become restricted by caking and bridging which occurs during transportation and storage. This issue probably results from storage moisture, temperature, relative humidity, particle size, time, or temperature variations. The objective of this study is to review the primary factors affecting flowability, handling, and storage of granular solids and powders, as well as appropriate test methodologies for these materials. Considering these will be helpful when examining granular flowability and storage challenges, including those surrounding the use of DDGS.