Premium
Distillation decoupling
Author(s) -
Luyben William L.
Publication year - 1970
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690160209
Subject(s) - decoupling (probability) , control theory (sociology) , distillation , nonlinear system , fractionating column , closed loop , mathematics , binary number , computer science , engineering , control engineering , chemistry , physics , control (management) , chromatography , artificial intelligence , quantum mechanics , arithmetic
This paper presents a quantitative study of two types of decoupling elements to achieve non‐interacting feedback control of overhead and bottoms compositions in binary distillation. Ideal decoupling, where the closed loop response of each loop is the same as it would be if the other loop were on manual control, and simplified decoupling, where two interaction compensators are used to isolate each loop, are investigated. The decoupling elements themselves are physically realizable in both cases, but unstable loops develop with ideal decoupling in higher purity columns because of increased positive feedback. Simplified decoupling gave effective, stable, noninteracting loops for all the cases studied. The decoupling elements are designed in the frequency domain from a linear model of the column, and their effectiveness is tested by digital simulation of the nonlinear column model.