Multicomponent distillation nomenclature

Multicomponent distillation, 393 absorption factor method, 398 azeotropic, 420-426 bubblepoint (BP) method, 406-409 computer program references. 404 concentration profiles, 394 distribution of non-kevs. 395 Edmister method, 398,399 extractive, 412, 417-422 feed tray location, 397 free variables, number of 395 Lewis-Matheson method 404 MESH eauations. 405-407 molecular, 425-427 nomenclature, 405 number of theoretical trays, 397 packed towers, 433-439 petroleum, 411-415 reflux, minimum, 397 reflux, operating, 397 SC (simultaneous correction) method, 408-411... 

Develop the state model for a multicomponent (C components) nonideal distillation column with N trays. Use the general nomenclature developed in Example 4.13 for the ideal binary distillation. 

The simplest case of batch distillation corresponds to use of the apparatus shown in Fig. 9.1. There is no reflux at any instant, vapor leaving the still pot with composition yo is assumed to be in equilibrium with the liquid in the still, and yn = Xp. Thus, there is only a single stage. The following nomenclature is used assuming that all compositions refer to a particular species in the multicomponent mixture. 

To illustrate the procedure, we consider a fairly complex process sketched in Fig. 6.4, which shows the process flowsheet and the nomenclature used. In the continuous stirred-tank reactor, a multicomponent, reversible, second-order reaction occurs in the liquid phase A + B C + D. The component volatilities are such that reactant A is the most volatile, product C is the next most volatile, reactant B has intermediate volatility, and product D is the heaviest component a/ > ac > olb > OiQ. The process flowsheet consists of a reactor that is coupled with a stripping column to keep reactant. A in the system, and two distillation columns to achieve the removal of products C and D and the recovery and recycle of reactant B. 

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