Effect of Relative Volatilities on Inferential Temperature Control of Reactive Distillation Columns

• Published in: Industrial & engineering chemistry research 2011-07, Vol.50 (13), p.8138-8152
• Main Authors: Kaymak, Devrim B, Yilmaz, Denizhan, Gürer, Ahmet Z
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical engineering; Distillation; Exact sciences and technology; Process Design and Control
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie102256j

Several control structures for different types of reactive distillation columns have been studied in the literature. In general, these are the ternary systems with the chemistry A + B ↔ C and the quaternary systems with the chemistry A + B ↔ C + D. In some cases, the ternary system may also contain an additional component I which is inert in terms of reaction. The growing literature includes both ideal generic and real chemical systems. However, all papers dealing with ideal generic systems assume constant relative volatilities between adjacent components. This paper explores the effect of temperature-dependent relative volatilities on inferential temperature control of reactive distillation columns. Three types of chemical systems are considered: a ternary system without inert component, a ternary system with inert component, and a quaternary system. Significant differences are observed between the results of these systems. The inferential control structure of the ternary system without inert provides effective control for any case of relative volatilities. However, there are some offset in bottoms and distillate compositions of quaternary system. The results illustrate that the magnitude of the offset in distillate composition increases significantly with the increase in the temperature-dependency of relative volatility.