Unveiling Optimal Operating Conditions for an Epoxy Polymerization Process Using Multi-objective Evolutionary Computation

The optimization of the epoxy polymerization process involves a number of conflicting objectives and more than twenty decision parameters. In this paper, the problem is treated truly as a multi-objective optimization problem and near-Pareto-optimal solutions corresponding to two and three objectives are found using the elitist non-dominated sorting GA or NSGA-II. Objectives, such as the number average molecular weight, polydispersity index and reaction time, are considered. The first two objectives are related to the properties of a polymer, whereas the third objective is related to productivity of the polymerization process. The decision variables are discrete addition quantities of various reactants e.g. the amount of addition for bisphenol-A (a monomer), sodium hydroxide and epichlorohydrin at different time steps, whereas the satisfaction of all species balance equations is treated as constraints. This study brings out a salient aspect of using an evolutionary approach to multi-objective problem solving. Important and useful patterns of addition of reactants are unveiled for different optimal trade-off solutions. The systematic approach of multi-stage optimization adopted here for finding optimal operating conditions for the epoxy polymerization process should further such studies on other chemical process and real-world optimization problems.

[1]  Sanjeev Garg,et al.  Multiobjective optimization of a free radical bulk polymerization reactor using genetic algorithm , 1999 .

[2]  Ajay K. Ray,et al.  APPLICATIONS OF MULTIOBJECTIVE OPTIMIZATION IN CHEMICAL ENGINEERING , 2000 .

[3]  Deoki N. Saraf,et al.  Use of genetic algorithms in the optimization of free radical polymerizations exhibiting the Trommsdorff effect , 1997 .

[4]  D. N. Butala,et al.  An experimental study of multiobjective dynamic optimization of a semibatch copolymerization process , 1991 .

[5]  G. Stephanopoulos,et al.  Multiobjective dynamic optimization of semibatch copolymerization reactors , 1982 .

[6]  Santosh K. Gupta,et al.  Multiobjective dynamic optimization of a nonvaporizing nylon 6 batch reactor , 1994 .

[7]  S. Gupta,et al.  Multiobjective optimization of an industrial nylon-6 semibatch reactor system using genetic algorithm , 1999 .

[8]  Kishalay Mitra,et al.  Multiobjective dynamic optimization of an industrial Nylon 6 semibatch reactor using genetic algorit , 1998 .

[9]  Anil Kumar,et al.  Reaction Engineering of Step Growth Polymerization , 1987 .

[10]  D. Butala,et al.  Multiobjective dynamic optimization of a semibatch free-radical copolymerization process with interactive cad tools , 1988 .

[11]  Kalyanmoy Deb,et al.  Unveiling innovative design principles by means of multiple conflicting objectives , 2003 .

[12]  Kalyanmoy Deb,et al.  Simulated Binary Crossover for Continuous Search Space , 1995, Complex Syst..

[13]  H. Batzer,et al.  Studies in the molecular weight distribution of epoxide resins. IV. Molecular weight distributions of epoxide resins made from bisphenol a and epichlorohydrin , 1977 .

[14]  H. Batzer,et al.  Studies in the molecular weight distribution of epoxide resins. II. Chain branching in epoxide resins , 1975 .

[15]  Kalyanmoy Deb,et al.  Muiltiobjective Optimization Using Nondominated Sorting in Genetic Algorithms , 1994, Evolutionary Computation.

[16]  Kalyanmoy Deb,et al.  A fast and elitist multiobjective genetic algorithm: NSGA-II , 2002, IEEE Trans. Evol. Comput..

[17]  Kaisa Miettinen,et al.  Nonlinear multiobjective optimization , 1998, International series in operations research and management science.

[18]  Kishalay Mitra,et al.  Effect of Caustic Addition in Epoxy Polymerization Process: A Single and Multi‐Objective Evolutionary Approach , 2004 .

[19]  J. Farber,et al.  Steady state multiobjective optimization of continuous copolymerization reactors , 1986 .

[20]  S. Gupta,et al.  Multiobjective optimization of an industrial semibatch nylon 6 reactor , 1995 .

[21]  B. Gupta,et al.  Modified polypropylene fibers with enhanced moisture absorption and disperse dyeability , 1999 .

[22]  R. A. Mashelkar,et al.  Frontiers in Chemical Reaction Engineering , 1984 .