Global optimization for the phase equilibrium problem using the NRTL equation

@inproceedings{citeulike:1779426, abstract = {Several approaches have been proposed for the computation of solutions to the phase and chemical equilibrium problem when the problem is postulated as the minimization of the Gibbs Free Energy function. None of them can guarantee convergence to the true optimal solution, and are dependent to a large extent on the initial starting point. Convergence to local optima often occurs, yielding incorrect phase and component distributions. In this work, the problem when the liquid phase is adequately modeled by the Non-Random Two Liquid (NRTL) activity coefficient expression is examined. The contribution of this work is twofold: firstly, a novel and important property of the Gibbs free energy expression involving the NRTL equation is provided. It is subsequently shown that by introducing new variables, the problem can then be transformed to one where a biconvex objective function is minimized over a set of bilinear constraints. Secondly, the Global OPtimization (GOP) algorithm (Floudas and Visweswaran, [3, 4]; Visweswaran and Floudas, [13, 14]) is used to exploit these induced properties of the formulation to guarantee convergence to an ?-global solution, regardless of the supplied initial point. The performance of the algorithm for a selected liquid-liquid equilibrium problem is examined.}, address = {Princeton Univ, Princeton, United States}, author = {Mcdonald, Conor M. and Floudas, Christodoulos A. }, citeulike-article-id = {1779426}, journal = {Inst Chem Eng Symp Ser}, keywords = {equilibrium, extraction, liquid, reactive}, number = {133}, pages = {273--280}, posted-at = {2007-10-17 12:39:18}, priority = {2}, publisher = {Publ by Inst of Chemical Engineers}, series = {Proceedings of the 4th European Symposium on Computer Aided Process Engineering}, title = {Global optimization for the phase equilibrium problem using the NRTL equation}, url = {http://www.scopus.com/scopus/record/display.url?view=extended\&origin=resultslist\&eid=2-s2.0-0027961582} }

TY - CONF ID - citeulike:1779426 L3 - citeulike-article-id:1779426 TI - Global optimization for the phase equilibrium problem using the NRTL equation SE - Proceedings of the 4th European Symposium on Computer Aided Process Engineering JF - Inst Chem Eng Symp Ser IS - 133 SP - 273 EP - 280 AD - Princeton Univ, Princeton, United States PB - Publ by Inst of Chemical Engineers N2 - Several approaches have been proposed for the computation of solutions to the phase and chemical equilibrium problem when the problem is postulated as the minimization of the Gibbs Free Energy function. None of them can guarantee convergence to the true optimal solution, and are dependent to a large extent on the initial starting point. Convergence to local optima often occurs, yielding incorrect phase and component distributions. In this work, the problem when the liquid phase is adequately modeled by the Non-Random Two Liquid (NRTL) activity coefficient expression is examined. The contribution of this work is twofold: firstly, a novel and important property of the Gibbs free energy expression involving the NRTL equation is provided. It is subsequently shown that by introducing new variables, the problem can then be transformed to one where a biconvex objective function is minimized over a set of bilinear constraints. Secondly, the Global OPtimization (GOP) algorithm (Floudas and Visweswaran, [3, 4]; Visweswaran and Floudas, [13, 14]) is used to exploit these induced properties of the formulation to guarantee convergence to an ?-global solution, regardless of the supplied initial point. The performance of the algorithm for a selected liquid-liquid equilibrium problem is examined. KW - equilibrium KW - extraction KW - liquid KW - reactive AU - Mcdonald, Conor AU - Floudas, Christodoulos UR - http://www.scopus.com/scopus/record/display.url?view=extended&origin=resultslist&eid=2-s2.0-0027961582 ER -