Integration of control aspects and uncertainty in the process design of polymerization reactors

Abstract In the last decades, the significant benefits of integrating control aspects in the early stages of process design have been shown. However, polymer engineering is just now incorporating this important methodology. Besides, the particularly difficult control problem of a grade transition in a polymerization reactor should be able to cope with process perturbations and uncertainty in the operating conditions and model parameters. In this work, a simultaneous process and control system design under uncertainty is performed for optimal grade transition operation. The process design includes reactor unit and initiator type selections. The control system design involves finding the best combination of controlled and manipulated variables, and the optimal controllers’ tuning parameters. Discrete design decisions are incorporated by means of discrete optimization variables. The resulting optimal design minimizes off-specification product during grade transition and guarantees feasible operation in the full range of the considered uncertain parameters and process perturbations.

[1]  M. Szesztay,et al.  Kinetics of radical polymerization. XXX. Polymerization of styrene in solution , 1980 .

[2]  Klavs F. Jensen,et al.  On‐line molecular weight distribution estimation and control in batch polymerization , 1994 .

[3]  Lorenz T. Biegler,et al.  Dynamic optimization of HIPS open-loop unstable polymerization reactors , 2005 .

[4]  W. Harmon Ray,et al.  Nonlinear dynamics found in polymerization processes — a review , 2000 .

[5]  Kyu Yong Choi,et al.  Analysis of steady state of free radical solution polymerization in a continuous stirred tank reactor , 1986 .

[6]  Coleman B. Brosilow,et al.  Nonlinear model predictive control of styrene polymerization at unstable operating points , 1990 .

[7]  J. D. Perkins,et al.  A case study in simultaneous design and control using rigorous, mixed-integer dynamic optimization models , 2002 .

[8]  Mariano Asteasuain,et al.  Simultaneous process and control system design for grade transition in styrene polymerization , 2006 .

[9]  W. Harmon Ray,et al.  Optimal-grade transition strategies for multistage polyolefin reactors , 1999 .

[10]  Chonghun Han,et al.  Plantwide Optimal Grade Transition for an Industrial High-Density Polyethylene Plant , 2003 .

[11]  Lorenz T. Biegler,et al.  New strategies for flexibility analysis and design under uncertainty , 2000 .

[12]  Howard P. Isermann,et al.  Operability of chemical reactors : multiplicity behavior of a jacketed styrene polymerization reactor , 1998 .

[13]  José Carlos Pinto,et al.  A survey of advanced control of polymerization reactors , 1996 .

[14]  E. Lima,et al.  Monitoring and control of styrene solution polymerization using NIR spectroscopy , 2003 .

[15]  L. Biegler,et al.  Large-scale dynamic optimization for grade transitions in a low density polyethylene plant , 2002 .

[16]  A. Brandolin,et al.  Simultaneous Design and Control of a Semibatch Styrene Polymerization Reactor , 2004 .

[17]  Sirish L. Shah,et al.  Computer optimal control of batch polymerization reactors , 1987 .

[18]  J. A. Bandoni,et al.  On optimising control and the effect of disturbances: Calculation of the open-loop backoffs , 1994 .

[19]  G. Odian,et al.  Principles of polymerization , 1981 .

[20]  Efstratios N. Pistikopoulos,et al.  New algorithms for mixed-integer dynamic optimization , 2003, Comput. Chem. Eng..

[21]  Kee J. Kim Modeling and Control of Continuous Free Radical Polymerization Reactors , 1991 .

[22]  B. Bequette,et al.  Product property and production rate control of styrene polymerization , 2002 .

[23]  R. H. M. Simon,et al.  Technology of Styrenic Polymerization Reactors and Processes , 1979 .

[24]  Nikolaos V. Sahinidis,et al.  Optimization under uncertainty: state-of-the-art and opportunities , 2004, Comput. Chem. Eng..

[25]  J. Macgregor,et al.  Optimal Grade Transitions in a Gas Phase Polyethylene Reactor , 1992 .

[26]  Efstratios N. Pistikopoulos,et al.  Optimal grade transition and selection of closed-loop controllers in a gas-phase olefin polymerization fluidized bed reactor , 2003 .

[27]  Lorenz T. Biegler,et al.  New faster for the steady-state back-off problem , 1998 .

[28]  Babatunde A. Ogunnaike,et al.  Process Dynamics, Modeling, and Control , 1994 .