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Abstract

In most industrial situations, powders and bulk solids have to be stored in and discharged from bins and silos. This can result in – often unexpected – problems, e.g., flow obstructions or segregation. Most of these problems can be avoided by proper design of equipment with respect to the flow properties of the bulk material to be stored. Especially important is the design of the hopper and all downstream equipment (e.g., feeder) having an influence of the flow in the hopper. In the present chapter the typical problems occurring in bins and silos are addressed, and the design of hoppers and related equipment with the goal to avoid these problems is outlined. Most important point is the determination of the hopper slope required to avoid stagnant zones, and the outlet dimensions to avoid flow obstructions like stable arches or ratholes. These quantities are calculated based on the flow properties of the respective bulk solid. The flow properties are quantities like, e.g., compressive strength and internal friction, and have to be measured with appropriate shear testers.

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... Deposition of the material part to the hopper walls due to adhesion, freezing, etc. Other particles of material can interact with each other to form an arch [1], [2]. Material development can occur relatively quickly. ...
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Thesis (doctoral)--Rheinisch-Westfälische Technische Hochschule Aachen, 1987.
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