column is a pure form of the reflux still.
It will condense all or most of the vapour at the top of the packing, and
return about 9/10 back down the column. The column will be quite
tall - say 600-1200mm (2-4 foot), and packed with a material high in
surface area, but which takes up little space (pot scrubbers are good
for this). It will result in an alcohol 95%+ pure (the theoretical
limit without using a vacuum is 95.6%), with no other tastes or
impurities in it. Note that both reflux and fractionating stills can still
be used to make whisky, rum etc, as they allow a very precise "cut" between the
heads, middle, and tail runs.
|Examples of Fractionating Columns