共查询到19条相似文献,搜索用时 750 毫秒
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间歇化工过程热集成问题的研究能够促进过程系统的可持续发展并且提高产业经济性和技术竞争力,顺应了化工发展大环境。本文介绍了以系统综合优化为目标的间歇化工过程热集成研究的发展现状,整理了早期研究的三大通用图解模型,并讨论和比较了在建模求解过程中常见算法。总结了当前研究的重点在换热网络设计优化、热储罐系统和考虑调度的热集成三个方面,并评述了与之相关的进展、瓶颈和研究意义。指出了热集成问题已成为当前间歇化工过程的研究热点,其中热集成和生产调度的协同优化十分必要,能够从系统全局的角度上给出优化方案。但由于间歇化工过程中存在较多的不确定性和约束条件,增加了热集成的研究难度,因此对间歇化工过程优化设计提出了更高的要求。 相似文献
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单产品间歇化工过程设计 总被引:3,自引:1,他引:3
本文修正了单产品间歇化工过程设计的数学模型并提出该问题的启发算法。该算法包括设备尺寸计算与过程综合。将实例计算结果与文献值进行了比较,证实了方法的正确性。 相似文献
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针对基于迭代学习控制的间歇过程产品质量优化控制算法难以进行收敛性分析的难题,并且考虑到实际生产中存在外部干扰和不确定因素的影响,本文对间歇过程模型参数动态更新问题进行了分析,建立了间歇生产过程产品质量的神经模糊(NF)预测模型,提出了一种新颖的批次轴参数自适应调节算法。在此基础上,构造了一种基于数据驱动的间歇生产过程产品质量迭代学习控制算法,并对优化问题的收敛性给出了严格的数学证明。最后,将本文提出的算法用于一类典型的间歇过程终点质量控制研究,仿真结果验证了本文算法的有效性和实用价值,为间歇过程的优化控制提供了一条新途径。 相似文献
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针对基于迭代学习控制的间歇过程产品质量优化控制算法难以进行收敛性分析的难题,以数据驱动的神经模糊模型为基础,提出一种新颖间歇过程的产品质量迭代学习控制方法。通过在优化算法中加入了新的约束条件,改变了最优解的搜索空间范围,从而使产品质量在批次轴上收敛,并创新性地对优化问题的收敛性给出了严格的数学证明。在理论研究的基础上,将提出的算法用于间歇连续反应釜的终点质量控制研究,仿真结果验证了本文算法的有效性和实用价值,为间歇过程的优化控制提供了一条新途径。 相似文献
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《高科技纤维与应用》2021,46(3)
复合材料是高度各向异性材料,其结构设计和分析方法等与金属结构存在诸多差异。尤其在复合材料结构优化过程中,强度、稳定性等设计因素众多,导致结构优化设计工作繁琐、优化效率不高。对于需要考虑大量强度约束的复合材料机翼结构初步设计,如何快速获取初始铺层方案成为制约复合材料机翼结构设计的关键之一。针对复合材料机翼结构初始方案快速获取的问题,构建了基于"设计区-关键元"思想的复合材料机翼结构二级优化设计方法,以层合板理论为基础,引入复合材料许用值工程算法,基于工程准则法,构建了复合材料铺层厚度及铺层比例的二级优化策略,基于自主结构分析软件HAJIF系统的有限元求解器,提出了基于全内存数据存取的复合材料结构二级优化方法,完善并开发了复合材料结构铺层优化设计软件。考虑典型复合材料机翼各个设计区强度约束,应用开发的软件完成了机翼结构复合材料壁板铺层厚度及铺层比例快速优化,为机翼精细化设计提供了技术及工具支撑。 相似文献
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A. Mesbah J. Landlust A.E.M. Huesman H.J.M. Kramer P.J. Jansens P.M.J. Van den Hof 《Chemical Engineering Research and Design》2010
Dynamic optimization is applied for throughput maximization of a semi-industrial batch crystallization process. The control strategy is based on a non-linear moment model. The dynamic model, consisting of a set of differential and algebraic equations, is optimized using the simultaneous optimization approach in which all the state and input trajectories are parameterized. The resulting problem is subsequently solved by a non-linear programming algorithm. 相似文献
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含再生再利用的用水网络的优化设计 总被引:4,自引:0,他引:4
对单组分含再生再利用的用水系统,提出了一种基于序贯操作模型的整体优化设计方法。该方法分别针对单组分含再生再利用的用水网络设计可能存在的三种情况,以新鲜水和再生水用量最小为目标,给出了相应的设计策略,数学的表达是一个非线性规划。首先依据规则将操作对贫流的要求进行分段排序,并通过引入操作的质量交换分配系数αi,将各操作依据规则虚拟地分配为再生前过程和再生后过程,然后按操作序列逐级进行操作和操作水源之间的的优化匹配,建立含再生再利用的用水网络的序贯操作模型,最后将此综合问题归结为非线性规划问题来求解,从而完成用水过程的设计。给出了一个实例,计算结果表明本文方法是有效和简便易行的。 相似文献
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Lorenz T. Biegler 《Theoretical Foundations of Chemical Engineering》2017,51(6):910-927
Process systems engineering faces increasing demands and opportunities for better process modeling and optimization strategies, particularly in the area of dynamic operations. Modern optimization strategies for dynamic optimization trace their inception to the groundbreaking work Pontryagin and his coworkers, starting 60 years ago. Since then the application of large-scale non-linear programming strategies has extended their discoveries to deal with challenging real-world process optimization problems. This study discusses the evolution of dynamic optimization strategies and how they have impacted the optimal design and operation of chemical processes. We demonstrate the effectiveness of dynamic optimization on three case studies for real-world reactive processes. In the first case, we consider the optimal design of runaway reactors, where simulation models may lead to unbounded profiles for many choices of design and operating conditions. As a result, optimization based on repeated simulations typically fails, and a simultaneous, equationbased approach must be applied. Next we consider optimal operating policies for grade transitions in polymer processes. Modeled as an optimal control problem, we demonstrate how product specifications lead to multistage formulations that greatly improve process performance and reduce waste. Third, we consider an optimization strategy for the integration of scheduling and dynamic process operation for general continuous/batch processes. The method introduces a discrete time formulation for simultaneous optimization of scheduling and operating decisions. For all of these cases we provide a summary of directions and challenges for future integration of these tasks and extensions in optimization formulations and strategies. 相似文献
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描述了超滤预处理系统的流程。依据微孔理论建立了超滤膜单元及系统模型,将系统的优化设计表达为一个非线性规划(NLP)问题,以年费用最小为目标函数,采用GAMS软件进行求解。结果表明,当进料液质量浓度高、产水水质要求低时,宜选用高通量膜;当进料液质量浓度低、产水水质要求高时,宜选用低通量膜。 相似文献
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聚四氟乙烯(PTFE)间歇聚合生产模式可满足小批量、多用途以及高质量产品的市场需求。针对PTFE聚合过程存在强非线性和大时滞特性,提出了一种基于自由终端的动态经济优化控制方法。首先,将生产周期作为一个自由度纳入优化变量建立动态经济优化问题,采用改进控制变量参数化方法,控制输入被离散为可变长度的片状序列,便可将动态经济优化问题转换为非线性规划(NLP)问题;然后,采用基于梯度下降的内点罚函数法求解NLP问题,通过变周期预测时域的滚动优化控制方法优化控制输入和终端时间;最后将提出的变周期动态经济优化控制与传统PI控制、非线性模型预测控制进行对比测试分析,仿真结果表明本方法单位经济效益更高,生产周期更短,突显了间歇生产的灵活性。 相似文献
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聚四氟乙烯(PTFE)间歇聚合生产模式可满足小批量、多用途以及高质量产品的市场需求。针对PTFE聚合过程存在强非线性和大时滞特性,提出了一种基于自由终端的动态经济优化控制方法。首先,将生产周期作为一个自由度纳入优化变量建立动态经济优化问题,采用改进控制变量参数化方法,控制输入被离散为可变长度的片状序列,便可将动态经济优化问题转换为非线性规划(NLP)问题;然后,采用基于梯度下降的内点罚函数法求解NLP问题,通过变周期预测时域的滚动优化控制方法优化控制输入和终端时间;最后将提出的变周期动态经济优化控制与传统PI控制、非线性模型预测控制进行对比测试分析,仿真结果表明本方法单位经济效益更高,生产周期更短,突显了间歇生产的灵活性。 相似文献
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This paper proposes the simultaneous integration of environmentally benign solvent selection (product design), solvent recycling (process design) and optimal control for the separation of azeotropic systems using batch distillation. The previous work performed by Kim et al. (2004. Entrainer selection and solvent recycling in complex batch distillation. Chemical Engineering Communications 191(12), 1606-1633) combines the chemical synthesis and process synthesis under uncertainty. For batch distillation, optimal operation is also important due to the unsteady state nature of the process and high operating costs. Optimal control allows us to optimize the column operating policy by selecting a trajectory for the reflux ratio. However, there are time-dependent uncertainties in thermodynamic models of batch distillation due to the assumption of constant relative volatility. In this paper, the uncertainties in relative volatility were modeled using Ito processes and the stochastic optimal control problem was solved by combined maximum principle and non-linear programming (NLP) techniques. Then the previous work of optimal solvent selection and recycling was coupled with optimal control. As a real world example for this integrated approach, a waste stream containing acetonitrile-water was studied. The optimal design parameters obtained by Kim et al. (2004. Entrainer selection and solvent recycling in complex batch distillation. Chemical Engineering Communications 191(12), 1606-1633), for this separation were used and the optimal control policy is computed first without considering uncertainties by variable transformation technique. The deterministic optimal control policy improves the product yield by 4.0% as compared to the base case, verified using a rigorous simulator for batch distillation. When the stochastic optimal control policy was computed representing the relative volatility as an Ito process, a similar recovery rate was obtained from simulations, but the batch time was reduced significantly, producing the most profitable operation. 相似文献