Distillation column design feed point location

An example of the steps outlined above is a two distillation column system designed to separate desired product B from component A (Fig. 4). The first is an extractive column (Cl) where the A/B mixture is fed at a location below the feed point for component S. The feed rate of S to Cl is to be maintained at a fixed ratio to the feed rate of A/B. Component A goes overhead from Cl as the vapor product from a partial condenser. The bottoms product from Cl is a B/S mixture, which is then fed to the second column (C2). C2 separates component B as the vapor overhead product from a partial condenser. The bottoms from C2, component S, recycles as feed back to Cl. 

Kirkbride equation An equation used for the design of distillation columns to determine the ratio of the number of trays above and below the feed point. It is therefore used to determine the location of the feed tray in the column ... 

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