In this study, an enthalpy-concentration method was applied in order to model a steady state continuous benzene-toluene mixture distillation column. For a distillation tower such as the benzene- toluene splitter, ther...In this study, an enthalpy-concentration method was applied in order to model a steady state continuous benzene-toluene mixture distillation column. For a distillation tower such as the benzene- toluene splitter, there are relatively few degrees of freedom that can be manipulated in order to minimize the total annualized cost. The reflux ratio can influence the steady-state operating point and therefore influence the total annualized cost. The trade-offs between reflux ratios and total annualized cost were discussed. The Cuckoo optimization algorithm was applied to obtain a correlation for the optimum value of the reflux ratio as a power function of the economic parameters of energy price and capital cost. The results show that, at low energy price or high capital cost, the optimum reflux factor is high.展开更多
An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are mad...An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are made for the various large-scale problems of varying size. The comparison results between ASTNA and the subspace limited memory quasi-Newton algorithm and between the modified augmented Lagrange multiplier methods combined with ASTNA and the modified barrier function method show the stability and effectiveness of ASTNA for simultaneous optimization of distillation column.展开更多
Reduced-space SQP algorithms for optimization of distillation column are studied.Variables decomposition is used to eliminate dependent variables and equality constraints,which reduce the dimension of QP sub-problems ...Reduced-space SQP algorithms for optimization of distillation column are studied.Variables decomposition is used to eliminate dependent variables and equality constraints,which reduce the dimension of QP sub-problems involved in iterations of SQP.Compared with the one based on orthonormal bases,reduced-space SQP based on orthogonal bases retains the convergence property while avoids QR decompositon.The improved computation efficiency is illustrated in a enzene/toluene distillation column optimization example, based on author’s,previous work.展开更多
建立基于严格机理的乙烯生产过程联塔系统开放式模型,采用大规模系统优化方法和自动微分方法,对此联塔系统进行大范围工况变化下的模拟。求解结果和收敛效率与Aspen P lus进行了对比。在初值相同、标度相同、建模和求解方式一致的情况下...建立基于严格机理的乙烯生产过程联塔系统开放式模型,采用大规模系统优化方法和自动微分方法,对此联塔系统进行大范围工况变化下的模拟。求解结果和收敛效率与Aspen P lus进行了对比。在初值相同、标度相同、建模和求解方式一致的情况下,本文联立求解方法的结果与Aspen P lus的EO模式的求解结果一致;对于进料工况大范围变化的情形,本文的联立求解方法收敛性明显优于Aspen P lus。采用大规模优化计算方法和稀疏自动微分方法对于提高求解效率、降低初值依赖性具有明显的效果。展开更多
文摘In this study, an enthalpy-concentration method was applied in order to model a steady state continuous benzene-toluene mixture distillation column. For a distillation tower such as the benzene- toluene splitter, there are relatively few degrees of freedom that can be manipulated in order to minimize the total annualized cost. The reflux ratio can influence the steady-state operating point and therefore influence the total annualized cost. The trade-offs between reflux ratios and total annualized cost were discussed. The Cuckoo optimization algorithm was applied to obtain a correlation for the optimum value of the reflux ratio as a power function of the economic parameters of energy price and capital cost. The results show that, at low energy price or high capital cost, the optimum reflux factor is high.
基金Project (2002CB312200) supported by the National Key Basic Research and Development Program of China Project(03JJY3109) supported by the Natural Science Foundation of Hunan Province
文摘An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are made for the various large-scale problems of varying size. The comparison results between ASTNA and the subspace limited memory quasi-Newton algorithm and between the modified augmented Lagrange multiplier methods combined with ASTNA and the modified barrier function method show the stability and effectiveness of ASTNA for simultaneous optimization of distillation column.
文摘Reduced-space SQP algorithms for optimization of distillation column are studied.Variables decomposition is used to eliminate dependent variables and equality constraints,which reduce the dimension of QP sub-problems involved in iterations of SQP.Compared with the one based on orthonormal bases,reduced-space SQP based on orthogonal bases retains the convergence property while avoids QR decompositon.The improved computation efficiency is illustrated in a enzene/toluene distillation column optimization example, based on author’s,previous work.
文摘建立基于严格机理的乙烯生产过程联塔系统开放式模型,采用大规模系统优化方法和自动微分方法,对此联塔系统进行大范围工况变化下的模拟。求解结果和收敛效率与Aspen P lus进行了对比。在初值相同、标度相同、建模和求解方式一致的情况下,本文联立求解方法的结果与Aspen P lus的EO模式的求解结果一致;对于进料工况大范围变化的情形,本文的联立求解方法收敛性明显优于Aspen P lus。采用大规模优化计算方法和稀疏自动微分方法对于提高求解效率、降低初值依赖性具有明显的效果。
