Question

How to improve the quality of product in batch distillaion column in terms of boil-up rate, pressure drops and the intensity of foaming on trays?

Answer 1

Batch distillation

In batch distillation process we distill a component from a mixture by heating the mixture slowly to reach the boiling point. The boil-up rate thus should be minimal with very low input of heat. A fast heating would yield mixture instead of a pure fraction. As the first fraction gets collected, the pressure suddenly drops before it takes up additional heat to reach the boiling point of the second component in the mixture. The drop in pressure clearly indicates the first component has completely come off from the mixture which is again a sign of good distillation. The intensity of foaming must be kept to a minimal as excessive foaming may lower tha rate of separation of the components in the gas phase.