The Product Is a Three-Component Mixture

Three-component mixture is a separation product of initial three-component mixture at nonsharp separation. 

Previously, we discussed sharp splits in the column section, which are important theoretical abstraction useful at the solution of the main questions of optimal designing of distillation units. 

If sharp separation is feasible, then product points at real separation can be located as much as one wants close to vertexes or sides of concentration triangle. We call such separation quasisharp one. If sharp separation is not feasible (i.e., at supposed sharp separation product point does not get into possible product segment Reg or Reg ), neither is quasisharp separation. In this case, only nonsharp separation is feasible, for that there is some minimum feasible content of admixture component or components. We call the separation at minimum feasible content of admixture component or components f/te best non-sharp one. 

Let s note, that distillation trajectory of three-component mixture for the set product point is located between trajectory at infinite reflux (ie., at L/V = 1, and reversible distillation trajectory) (Kiva, 1976 Petlyuk Serafimov, 1983 Wahn-schafft et al, 1992 Castillo, Thong, Towler, 1998). 

The region of two-directed distillation (pitchfork region Regpuch) is located between the hne of the best product compositions (pitchfork distillation boundary) and boundary of distillation regions at infinite reflux Reg°° (Castillo et al., 1998 Davydyan, Malone, Doherty, 1997 Wahnschafft et al., 1992). 

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