Distillation Lab

Introduction

Distillation columns are used to separate fluid components. A stream entering feeds the fluid to be separated. As it falls down the column it condenses the vapors that are moving up the column. Eventually the fluid reaches a reboiler that heats the fluid at a boiling temperature higher than the most volatile component but lower than the least volatile component. This causes vapor to form with a higher concentration of the more volatile component. The vapor formed flows up the column where it enters trays through a sieve like surface. The vapor bubbles up through the liquid portion of the tray and up through the vapor portion. The vapor leaving a tray flowing up is theoretically in equilibrium with the fluid that is flowing down and out. The concentration of the more volatile component in the vapor leaving a tray is higher than the vapor entering. The concentration of the more volatile component in the liquid leaving a tray is lower than entering. The vapor that leaves the tray at the top of the column enters a condenser. The overheated product known as the distillate flows out of the system while the liquid product known as the reflux flows back in [1].

The distillation was carried out at a reflux ratio of 2 for the duration of this lab. The data collected was used to solve the design problem which uses a binary distillation system with a reflux ratio of 2. At steady state the compositions in the liquid phase of each component in the reboiler, the six trays, and the distillate were measured with gas chromatography. The composition of the components is related to the area under the curve that the gas chromatographer produces. Composition was used to determine tray efficiency by comparing the results with what was to be