multicolumn rectifying system

A multicolumn rectifying system is an apparatus used in the process of rectification, which purifies substances like alcohol through repeated distillation. This system typically comprises three to five columns, each designed for specific separation tasks.1

The process begins with a preliminary separation column, often called a beer still or analyzer, which uses plates and baffles to control liquid levels. This column produces a product with an ethyl alcohol concentration between 55 and 80 percent. A two-column system, including a beer column and a rectifying column, can yield a 95 percent alcohol product, with the rectifier removing esters and higher alcohols as side streams.1

Multicolumn systems offer enhanced control over the final product by incorporating specialized rectifiers. An aldehyde column, or purifier, is often used to separate highly volatile, low-boiling components. Sometimes, an extractive column is employed to recover ethyl alcohol, which is then returned to the rectifier. The separation and retention of flavoring compounds are influenced by their boiling points, solubilities in alcohol and water, and specific gravities.1