A distillation column works by catching liquid vapor as it rises. The vapor cools and turns into liquid, with the liquid collected at the highest point of the column (also called the distillate) being the most sought-after component. Industrial-sized columns usually have a number of trays in the column to catch differing levels of distilled liquids as they condense.
The process begins with the liquid that is to be distilled being fed into the column via the feed tray.
The column itself is composed of two main sections, called the stripping section at the bottom and the enriching section at the top. The stripping section is where unwanted liquid is collected, while the enriching section is where the desired compounds or product is condensed back into liquid.
The heat that is required to turn the liquid into vapor is generated via the reboiler. Once the vapor has been cooled via a condenser, it is deposited in the reflex drum. The contents of the reflex drum are then split and some is sent back to the distillation column.
The distillate is the product of the process that is removed from the distillation system entirely after being deposited in the reflex drum. It is this product that is normally the aim of the overall process.