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Batch distillation is one of the oldest separation processes. It is still widely used in chemical industry due to its flexibility: one column can be used for multicomponent separations and for different mixtures.

Design of batch distillation is discussed, with special attention to thermodynamic properties of the mixture. Selection of process parameters (heat duty, reflux ratio, pressure and cut sizes) plays important role in process optimization. In non-ideal systems the products obtained from batch distillation may be counterintuitive; for example the less-volatile components can be obtained before the more-volatile species.

Typical operating steps depend on the feed mixture and distillation objectives (how many products need to be made and what is the desired purity). These steps may include charging, heating and degassing, establishing reflux, low-boils cut, front cut, pure cut, after cut, pumping out or washing the pot. Operational details of all these steps are discussed; for example the feed line size impacts the time of the batch; or flashing product tanks in the first batch is necessary to reach the purity specification. Most of these operational details are dictated by common sense but they are necessary for running successful batch distillation.

Some examples of plant trials are given.