Vr. Ahon et Jl. De Medeiros, Optimal programming of ideal and extractive batch distillation: single vessel operations, COMPUT CH E, 25(7-8), 2001, pp. 1115-1140
This work addresses the problem of optimal programming of multi-component b
atch distillation columns with a single vessel (batch rectifier, batch stri
pper, middle vessel and extractive middle vessel) so as to maximize an annu
alized profit function. A smooth price function is formulated for product v
aluation, allowing to release traditional purity constraints. The solution
is the optimal batch policy of top/bottom withdrawals. A simplified cascade
model is developed for separation calculations, offering several operation
al patterns. Ideal and non-ideal mixtures can be handled with this model th
at is proposed as a substitute for traditionally used Fenske-Underwood-Gill
iland cascades. Batch separations of ideal quaternary feeds are optimally p
rogrammed for the first three operations aforementioned. The extractive mid
dle vessel column was optimally programmed for production of anhydrous etha
nol from hydrated, nearly azeotropic, alcohol with ethylene-glycol as entra
iner. All applications considered fixed number of stages, heat duty, and, i
n the extractive system, fixed pump-around rate of entrainer. (C) 2001 Else
vier Science Ltd. All rights reserved.