Analysis and Simulation of a Batchwise Scotch Whisky Production Process

Thomas Benton Rogers, University of Tennessee, Knoxville

Abstract

Scotch whiskey is produced in a two step distillation process that has remained relatively unchanged for decades, even centuries. The chemical composition of the whiskey is vital to its flavor and character. Much work has been done to analyze and study the final composition of different whiskies. However, to date little work has been published that studies the composition of the distillate with respect to distillation time. The goal of this work is to develop an experimental basis for study of the scotch whisky production process. Experimental data would allow us to gain a better understanding of the effects of distillation and aging. Samples collected during the distillation process were analyzed using gas-chromatography mass spectrometry. This analysis allowed the development of composition curves for several components found in whisky to help understand process decisions made during the distillation. The experimental data developed during the chemical analysis provided a physical basis for development of a process simulation. The simulation was done using the HYSYS® Simulation software. The batch distillation process was modeled using a tray distillation column with a large reboiler and low reflux. These conditions closely mimic the operation of the actual process. The simulation successfully modeled the experimental data for both the major and minor components. Simulation studies have also been able to produce suggestions for process improvements that could increase the economic yield of the distillery.