Plug flow in malt bins.

Babcock, D.R.

Abstract
Using coloured plastic beads, the flow of malt from malt bins was examined. Without any device to prevent it, the bin will funnel, i.e. it will empty in a last in, first out manner. Husk material will segregate and the last few brews from such a bin will contain abnormal amounts of husk. It was found that the installation of an offset pyramid in the base of the bin gave plug flow or first in, first-out characteristics. The pyramid was, in effect, a mirror image of the bin bottom, offset by 45 degrees, which thus reduced the effective open area of the bin bottom by 50%. Perfect plug flow was obtained so long as the bin remained 1/3 to 1/2 full but broke down when the bin was emptied. This was not a disadvantage in normal operation since the bin was only emptied for quarterly cleaning and fumigation.
Keywords: flow malt silo storage