Product regions under infinite reflux

Figure 3.4. (a) Product region under infinite reflux for given xp and different number of trays and D/F. Ideal four-component mixture > K2 > > K4),... 

Figure 3.9. Subregions of distillation under infinite reflux Regsa for some structures of three-component mixtures and product regions for given xp, 3,4a,4b... — classification according to Gurikov (1958). Product regions are shaded bottom regions are darker shaded.

As we will see in Chapter 3, the distillation region and subregion characterize those possible product compositions that can be produced from the given feedstock composition by distillation under one of the most important modes, in particular, under the infinite reflux mode. 

The main difference between the azeotropic mixtures (and also nonideal zeo-tropic mixtures) and the ideal ones are that, to determine possible sphts of an azeotropic mixture, special analysis is required. The availability of a few distillation regions under the infinite reflux Reg can result in sharp separation becoming completely impossible or in a decrease in sharp splits number. Let s note that for ideal mixtures the fine of possible products compositions atR = ooandiV=oo and set feed composition goes partially inside the concentration simplex and partially along its boundary elements. For azeotropic mixtures, this line can go along the boundary elements of the distillation region (Fig. 3.6a, line 2). 

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