The column still works by heating a liquid mixture, which generates vapors. These vapors ascend through the distillation column, which is equipped with plates or trays at different levels, or a packing, which provides surfaces for the condensate to reflux.
As the vapors rise, they come into contact with cold surfaces within the column and partially condense. This downward liquid reflux meets rising vapors, and an exchange of heat and mass occurs. The more volatile components tend to rise, while the less volatile components condense and return to the bottom of the column. Through this continuous process, the mixture is progressively separated into its components based on their boiling points.