Welcome To Still
A still is a permanent apparatus used to distill miscible or immiscible (eg. steam distillation) liquid mixtures by heating to selectively boil and then cooling to condense the vapor. Stills have been used to produce perfume and medicine, Water for Injection (WFI) for pharmaceutical use, generally to separate and purify different chemicals, and most famously, to produce distilled beverages containing ethyl alcohol.
Since ethyl alcohol boil at a lower temperature than water, a common application of the process of distillation is to produce a strong alcoholic drinks. Usually a still used for this purpose is made of copper, since it removes sulfur-based compounds from the alcohol that would make it unpleasant to drink. Modern stills are made of stainless steel with copper innards (piping, for example, will be lined with copper along with copper plate inlays along still walls).
Reflux is a technique involving the condensation of vapors and the return of this condensate to the system from which it originated. It is used in industrial and laboratory distillations. It is also used in chemistry to supply energy to reactions over a long period of time.
A column still, also called a continuous still, patent still or Coffey still, is a variety of still consisting of two columns invented in 1826 by Robert Stein, a Clackmannanshire distiller and first used at the Cameron Bridge Grain Distillery. The design was enhanced and patented in 1831 by an Irishman, Aeneas Coffey. The first column (called the analyser) has steam rising and wash descending through several levels. The second column (called the rectifier) carries the alcohol from the wash where it circulates until it can condense at the required strength.
A pot still is a type of still used in distilling spirits such as whisky or brandy. Heat is applied directly to the pot containing the wash (e.g. for whisky) or wine (for brandy). This is called a batch distillation (as opposed to a continuous distillation).