Simultaneous Separation of Light and Heavy Impurities by a Complex Batch Distillation Column.

Abstract

The characteristics of a new type of batch distillation column called the “complex batch distillation column” are examined. In the complex column, the feed is supplied to the middle of the column, and the light and heavy components are withdrawn from the top and the bottom at the same time. The liquid on the feed tray is recycled to the feed tank so as to accumulate the intermediate component in the tank. The complex column is convenient for removing light and heavy impurities from raw materials since the impurities can be withdrawn simultaneously from the top and the bottom. The complex column is similar to a combined system of ordinary and stripping batch distillation columns where the condenser of the stripping column is heat-integrated with the reboiler of the ordinary column. Therefore, it can be expected that separation can be executed effectively compared with the ordinary column. In this paper, by analyzing the differences between ordinary and stripping batch distillation columns, the conditions at which the complex column works effectively compared with an ordinary batch distillation column, are clarified.