This paper firstly reviews the requirements for container and hopper design for reliable discharge. Discussion is then
directed to the evaluation of the consolidation stresses acting in both in both the cylinder and hopper sections during both
initial and flow conditions. Here the vast difference, especially in vicinity of the bin outlet, between the initial or filling
and flow conditions is highlighted. This vast difference has major design and operation implications. A further major
implication is that all bulk solids must dilate to flow. The opportunity to simultaneously attain reliable discharge and
partial moisture removal is also examined.
The selection of design parameters to maximise the consolidation stresses in both the cylindrical and hopper sections is
detailed. In regard to the latter, it is recommended fine coal bins be discharged using low friction lined transition
hoppers with large outlet spans. Such outlets will discharge fine coal in a relatively compacted state. This compaction
state should exhibit minimum water retention and short term moisture uptake.