基于参数批次调整模型的间歇精馏最小时间优化策略

Abstract

针对间歇精馏过程优化计算中模型的准确性和计算复杂度之间的矛盾,提出了一种确定馏出液摩尔分数和操作时间的简化模型.该模型假定在塔釜内轻组分摩尔分数固定的情况下,馏出液平均摩尔分数与回流比变化量之间呈线性关系,其比例定义为回流比调节敏感系数.利用间歇精馏的批次重复操作特点,提出了模型敏感系数沿批次指标的在线更新机制,保证了简化模型在不同生产状态下的准确性.基于该简化模型,以回流比为优化决策变量,提出了针对最小生产时间问题的优化方案.利用ASPEn bATCH dISTIllATIOn(Abd)中的模型作为实验对象原型,进行了优化算法的仿真实验.仿真结果表明基于批次参数调整策略的最小时间优化方案能够实现优化指标随生产批次的增加而不断减少.

To solve the contradiction between the accuracy and the computational complexity of model for optimization calculation,a simplified model of batch distillation is firstly presented in this paper to calculate the concentration of the end-product and operating time.For simplicity,the model assumed that the relationship between the concentration of product and reflux ratio can be described by a parameterized linear model where the parameter is referred to as sensitivity coefficient of the process.Based on the simplified model,an optimization strategy for minimizing the operating time of batch distillation is also proposed.As the batch to batch updated mechanism for the sensitivity coefficient of the model adopted in the optimization algorithm,the accuracy of the model is refined,resulting in the optimal operating time decreased from batch to batch.By using Aspen Batch Distillation model as the numerical plant,the optimization algorithm is implemented.The simulation results demonstrate the feasibility of the proposed optimal algorithm and verified the convergence of operating time from batch to batch.