基于Aspen仿真的乙醇水溶液精馏方案优化

Optimization of aqueous ethanol distillation based on Aspen simulation

为了实现对乙醇水溶液精馏方案进行优化设计,本文首先基于物料平衡、相平衡、物流各组分摩尔分率归一化以及热量平衡,针对整个填料塔精馏过程建立了稳态和动态模型,并利用数学模型对每部分精馏操作时的关键参数以及能耗进行了理论计算。为了检验数学模型和理论计算的合理性,同时鉴于Aspen Plus和Aspen Dynamics中已经建立了完善的精馏塔模型,本文以乙醇水溶液精馏方案为例,以达到浓度和回收率要求为约束条件,过程中最小能耗为目标函数,对回流比、馏出液流量、进料流量、进料温度、塔釜加热功率等几个输入变量分别进行了灵敏度分析,对理论计算的操作变量进行校正,确定出实际操作中的操作变量,优化乙醇水溶液精馏过程,从而得到最优的精馏操作序列。

In this study, in order to optimize the distillation of aqueous ethanol solution, the steady stateand dynamic model are established for the whole distillation process of the packed tower based on materialbalance, phase balance, normalization of each component mole fraction and heat balance. The keyparameters and energy consumption of each fractional distillation operation are calculated. At the same time,in order to verify the rationality of mathematical model and theoretical calculation, Aspen Plus and AspenDynamics are utilized to establish a complete distillation column model, and distillation of aqueous ethanolsolution is taken as the example. Taking the concentration and recovery requirements as the constraints, theminimum energy consumption as the objective function, the sensitivity of reflux ratio, distillate flow, feedflow, feed temperature, tower heating power and some other input variables are analyzed. The theoreticalcalculation of parameters are corrected to determine the actual operation of the operating parameters, andwe obtain the optimal operation sequence of distillation of aqueous ethanol solution.