The reflux process in distilling allows the distiller to increase the alcohol by volume (ABV) of their final product and remove unwanted flavoring by using different technics to condense higher boiling point components in the column before reaching the final condenser for collection. A reflux system can yield high proof spirits; normally 95% ABV which is the highest a distiller can achieve without using chemicals or expensive and complicated equipment.
Some reflux stills use a secondary condenser (dephlegmator) in the vapor path to the final condenser. By controlling the water temperature in the dephlegmator higher boiling point components will prematurely condense and return to the boiler. By managing the vapor temperature and the dephlegmator ethanol will pass on to the final condenser and everything else is returned to the boiler.Many reflux still designs used by home distillers utilize “packing”. Packing is used to increase the surface area inside the column. Once reflux begins inside the column the distillate drops back down to the boiler and passes though the packing causing droplets to form in and on the packing. Vapor then passes though the packing and droplets leaving behind unwanted components and increasing alcohol proof. Packing can be many types of materials, sizes or shapes like marbles, ceramic saddles or raschig rings. But the most popular packing material is wire mesh, normally copper or stainless steel.
Additional systems used for reflux will be explained in more detail on the still specific pages.