This paper proposes a stochastic optimal technique based on Genetic Algorithm (GA) for the calculation of multiphase and multicomponent chemical equilibrium by minimization of Gibbs free energy. Three aspects are impr...This paper proposes a stochastic optimal technique based on Genetic Algorithm (GA) for the calculation of multiphase and multicomponent chemical equilibrium by minimization of Gibbs free energy. Three aspects are improved based on the drawbacks of the conventional GA.An alternative decimal encoding strategy is adopted to enhance the precision of calculation.A dynamic encoding method that can limit the bounds of optimized variables within their feasible regions is developed to cope with the complex constraints of the problem.Finally,sequential search technique is applied to improve GA to approach global optima.It is shown through the calculation of complex chemical systems,in which non-ideal,multireaction and multiphase coexistence are simultaneously involved,that the presented GA is general and efficient for the addressed problem.展开更多
This paper addresses the application of stochastic optimization approaches to the synthesis of heatintegrated complex distillation system, which is characterized by large-scale combinatorial feature. Conventionaland c...This paper addresses the application of stochastic optimization approaches to the synthesis of heatintegrated complex distillation system, which is characterized by large-scale combinatorial feature. Conventionaland complex columns, thermally coupled (linked) side strippers and side rectifiers as well as heat integration betweenthe different columns are simultaneously considered. The problem is formulated as an MINLP (mixed-integernonlinear programming) problem. A simulated annealing algorithm is proposed to deal with the MINLP problemand a shortcut method is applied to evaluate all required design parameters as well as the total cost function. Twoillustrating examples are presented.展开更多
文摘This paper proposes a stochastic optimal technique based on Genetic Algorithm (GA) for the calculation of multiphase and multicomponent chemical equilibrium by minimization of Gibbs free energy. Three aspects are improved based on the drawbacks of the conventional GA.An alternative decimal encoding strategy is adopted to enhance the precision of calculation.A dynamic encoding method that can limit the bounds of optimized variables within their feasible regions is developed to cope with the complex constraints of the problem.Finally,sequential search technique is applied to improve GA to approach global optima.It is shown through the calculation of complex chemical systems,in which non-ideal,multireaction and multiphase coexistence are simultaneously involved,that the presented GA is general and efficient for the addressed problem.
基金Supported by the National Fundamental Research Development Program of China (No. 2000026308).
文摘This paper addresses the application of stochastic optimization approaches to the synthesis of heatintegrated complex distillation system, which is characterized by large-scale combinatorial feature. Conventionaland complex columns, thermally coupled (linked) side strippers and side rectifiers as well as heat integration betweenthe different columns are simultaneously considered. The problem is formulated as an MINLP (mixed-integernonlinear programming) problem. A simulated annealing algorithm is proposed to deal with the MINLP problemand a shortcut method is applied to evaluate all required design parameters as well as the total cost function. Twoillustrating examples are presented.
