Distillation technology has been used worldwide throughout the chemical industry for many years, originally being invented in China around 800 BC. There are currently over 40,000 columns in operation worldwide [29]. Although there are many variations in column types, sizes, tray configurations, etc., the underlying principle is the same. Distillation is the physical process of heating a liquid mixture to separate components based the relative volatilities of each component. Distilleries consume about 40% of the total energy used to operate plants in the chemical industry, and over 95% of that energy is used in separation processes [31]. Therefore, improving distillation technology is one area that chemical engineers are working to transform into a more efficient process by use of process intensification. The purpose of this research was to investigate the possible economic and energy impacts of a form of process intensification called ‘cyclic distillation’ as well as its application to the distilled spirits industry. Cyclic distillation is an alternate mode of operation first proposed and studied by Cannon and McWhirter in the 1960’s. The ‘cycle’ consists of alternating between two periods, vapor flow and liquid flow. During the vapor flow period heat is supplied to the column, vapor flow upwards and distillate is collected as in normal operation. During the liquid flow period, the heat source is ceased and the liquid on each tray is transferred to the tray below. The cycle of alternating between the two periods is continued for the entire distillation. Cyclic distillation has been applied to many different systems and configurations and has been demonstrated experimentally and theoretically to increase column throughput, lower energy requirements and achieve higher separation performance.In this study, a 150 L Carl © still was used to distill fermented apple cider and apple brandy low wines. Cyclic distillation and conventional operation were compared using the same system. Distillation samples were collected and analyzed using a gas chromatograph. The system was also simulated using MATLAB.In summary, cyclic distillation on the batch column used was able to show a decrease in energy (steam) requirements for finishing runs but not in stripping runs. Cyclic distillation trends included ethanol concentration decreased at a slower rate compared to conventional operation and as a result temperature profiles mimicked this phenomenon. It was shown that the volume of hearts (product) was increased and volume of tails and heads (unwanted by-products) was decreased. This research has shown that the application of cyclic distillation on spirit production is a viable option for distilleries large and small. In extension of this work, it is suggested that cyclic distillation is applied to other types of spirits and to columns with a larger number of trays, and to trays with true plug flow capability.
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