Separation of Liquid Mixtures and the Minimum Steam Rectification Stream

In this paper, we compare various estimates of the abilities of liquid mixtures to be separated by distillation. The minimum specific heat consumption in rectification is shown to be proportional to the fraction of the upper product and the minimum reflux ratio. The conditions for energetically favorable application of different schemes of separation of three-component mixtures are determined. We also calculated the minimum reflux number for real binary mixtures with the possibility of forming pinch regimes. In the presence of a pinch mode in the strengthening part of the column, the value of the minimum reflux ratio is proved to be independent of the aggregate state of the initial mixture. For this case, we derived a formula for calculating the minimum reflux ratio taking the energy level of the initial mixture into account.