A reflux still is a type of column still. Column stills, also known as continuous stills, are used for large-scale distillation and are commonly found in commercial distilleries. They are designed to produce high-proof alcohol efficiently and consistently.
A reflux still operates on the principle of reflux, which involves the condensation and re-vaporization of the alcohol vapors. This process helps to separate and purify the alcohol by removing impurities and unwanted flavors.
The main component of a reflux still is the column. The column is a tall, vertical cylinder that is packed with various materials, such as copper mesh, ceramic Raschig rings, or stainless steel scrubbers. These materials provide a large surface area for contact between the rising alcohol vapors and the descending liquid, usually a reflux liquid or a reflux condenser.
The reflux liquid, often water or a water-alcohol mixture, is introduced at the top of the column. As the alcohol vapors rise, they come into contact with the cooler reflux liquid and condense. The condensed liquid then flows back down the column, while the non-condensable gases continue to rise.
The purpose of this reflux process is to increase the number of distillations that occur within the column. Each time the alcohol vapors condense and re-vaporize, they undergo a mini-distillation, which helps to separate impurities and increase the overall purity of the distillate.
The height and width of the column, as well as the packing material used, are important factors in determining the efficiency and effectiveness of the reflux still. A taller column with more packing material will provide greater contact between the vapors and the reflux liquid, resulting in a higher level of purification. However, a longer column may also slow down the distillation process.
In addition to the column, a reflux still also includes a condenser, which is responsible for cooling the alcohol vapors and turning them into liquid form. The condenser can be either a simple tube or a more complex design, such as a shell and tube condenser or a plate heat exchanger.
A reflux still is a type of column still that uses the process of reflux to produce high-proof alcohol with a high degree of purity. While it may produce less flavorful alcohol compared to a pot still, it is a popular choice for those who prioritize efficiency, consistency, and the removal of impurities in their distillate.