An extended ant colony optimization algorithm for integrated process and control system design Martin SchlÄutera, Jose A. Egeab, Luis T. Antelob, Antonio A. Alonsob, Julio R. Bangab
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[email protected] a Theoretical & Computational Optimization Group, University of Birmingham Birmingham B15 2TT, United Kingdom b Process Engineering Group, Instituto de Investigaciones Marinas (IIM-CSIC) 36208 Vigo, Spain 6th May 2009 Abstract The problem of integrated process and control system design is discussed in this paper. We formulate it as a mixed integer nonlinear programming problem subject to di®erential- algebraic constraints. This class of problems is frequently non-convex and, therefore, local optimization techniques usually fail to locate the global solution. Here we propose a global optimization algorithm, based on an extension of the Ant Colony Optimization metaheuristic, in order to solve this challenging class of problems in an e±cient and robust way. The ideas of the methodology are explained and, on the basis of di®erent full-plant case studies, the performance of the approach is evaluated. The ¯rst set of benchmark problems deal with the integrated design and control of two di®erent wastewater treatment plants, consisting on both NLP and MINLP formulations. The last case study is the well-known Tennessee Eastman Process. Numerical experiments with our new method indicate that we can achieve an im- proved performance in all cases. Additionally, our method outperforms several other recent competitive solvers for the challenging case studies considered. Keywords: Integrated process and control system design, mixed integer nonlinear program- ming (MINLP), metaheuristics, Ant Colony Optimization, Tennessee Eastman Process, oracle penalty method.