Advertisement

Korean Journal of Chemical Engineering

, Volume 23, Issue 4, pp 540–546 | Cite as

Nonlinear model based control of two-product reactive distillation column

  • Myungwan Han
  • David E. Clough
Article

Abstract

Nonlinear feedback control scheme for reactive distillation column has been proposed. The proposed control scheme is derived in the framework of Nonlinear Internal Model Control. The product compositions and liquid and vapor flow rates in sections of the reactive distillation column are estimated from selected tray temperature measurements by an observer. The control scheme is applied to an example reactive distillation column in which two products are produced in a single column and the reversible reaction A+B=C+D occurs. The relative volatilities are favorable for reactive distillation so that the reactants are intermediate boilers between the light product C and the heavy product D. Ideal physical properties, kinetics, and vapor-liquid equilibrium are also assumed. It is shown that the proposed control scheme keeps tight product composition control.

Key words

Reactive Distillation Nonlinear Internal Model Control Dual Composition Control 

Nomenclature

A

reactant component

B

reactant component; bottoms flow rate [kmol/s]

C

product component

D

product component; distillate flow rate [kmol/s]

EB

activation energy of the reverse reaction [cal/mol]

EF

activation energy of forward reaction [cal/mol]

EOA

fresh feed flow rate of reactant A [kmol/s]

FOB

fresh feed flow rate of reactant B [kmol/s]

kF

specific reaction rate of the forward reaction [kmol ·-1 · kmol-1]

kB

specific reaction rate of the reverse reaction [kmol·s-1 · kmol-1]

Ln

liquid flow rate from tray n [kmol/s]

Mn

liquid holdup on tray n [kmol]

rs

liquid flow rate in the stripping section

Vs

vapor flow rate in the stripping section

rr

liquid flow rate in the rectifying section

Vr

vapor flow rate in the rectifying section

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Al-Arfaj, M. and Luyben, W. L., “Comparison of alternative control structures for an ideal two-product reactive distillation column,”Ind. Eng. Chem. Res.,39, 3298 (2000).CrossRefGoogle Scholar
  2. Balasubramhanya, L. S. and Doyle, F. J.,Nonlinear model-based control of a batch reactive distillation column, DYCOPS-5, Corfu, Greece, June 8–10 (1998).Google Scholar
  3. Barlett, D.A. and Wahnschafft, O.M.,Dynamic simulation and control strategy evaluation for MTBE reactive distillation, Paper presented at FOCAP (1999).Google Scholar
  4. Barolo, M. and Berto, F., “Composition control in batch distillation: binary and multicomponent mixtures,”Ind. Eng. Chem. Res.,37, 4689 (1998).CrossRefGoogle Scholar
  5. Bock, H., Wozny, G. and Gutche, B., “Design and control of a reaction distillation column including the recovery system,”Chem. Eng. Progress.,36, 101 (1997).CrossRefGoogle Scholar
  6. Guttinger, T. E. and Morari, M., “Predicting multiple steady states in equilibrium reactive distillation. 1. Analysis of nonhybrid systems,”Ind. Eng. Chem. Res.,38, 1633 (1999).CrossRefGoogle Scholar
  7. Kumar, A. and Daoutidis, P., “Dynamics and control of an ethyl acetate reactive distillation column,”AIChE J.,45, 51 (1999).CrossRefGoogle Scholar
  8. Lim, C. and Han, M., “Profile position control of reactive batch distillation column,”Journal of Control, Automation and Systems Engineering,7(3), 263 (2001).Google Scholar
  9. Monroy-Loperena, R. and Alvarez-Ramirez, J., “Output-feedback control of reactive batch distillation columns,”Ind. Eng. Chem. Res.,39, 378 (2000).CrossRefGoogle Scholar
  10. Quintero-Marmol, E. and Luyben, W., “Inferential model-based control of multicomponent batch distillation,”Chem. Eng. Sci.,47, 4, 887 (1992).CrossRefGoogle Scholar
  11. Sneesby, M.G., Tade, M.O., Data, R. and Smith, T.N., “Detrimental influence of excessive fractionation on reactive distillation,”AIChE J.,44, 388 (1998).CrossRefGoogle Scholar

Copyright information

© Korean Institute of Chemical Engineering 2006

Authors and Affiliations

  1. 1.Department of Chemical & Biological EngineeringChungnam National UniversityDaejeonKorea
  2. 2.Department of Chemical & Biological EngineeringUniversity of ColoradoBoulderUSA

Personalised recommendations