基于Aspen Plus的Petlyuk塔模拟与优化

Simulation and optimization of Petlyuk column by Aspen Plus

利用Aspen Plus软件,对Petlyuk塔进行模拟和优化。采用三塔等效流程,进行简捷计算,确定Petlyuk塔的初始参数。在初始参数下,利用Aspen Plus的Multifrac-Petlyuk模块严格模拟,并利用Sensitivity模块,分别优化回流比R、进料位置、侧线出料位置、互连位置及互连物流流量等参数。以乙醇-正丙醇-正丁醇三元体系为例,模拟和优化结果为:主塔塔板数58,预分塔塔板数29,进料在预分塔第12块板,侧线出料在主塔第28块板,主塔摩尔回流比4.6,预分塔塔顶和主塔互连位置在主塔第18块板,塔底和主塔互连位置在第47块板,主塔返回预分塔顶部的液相流量为65 kmol/hr,返回预分塔底部的气相流量为145 kmol/hr。在此优化参数下,可得到98.9%乙醇、98.7%正内醇和99.0%正丁醇,达到分离要求。模拟和优化的结果对工业化设计和生产具备指导意义。

Simulation and optimization of Petlyuk column was carried out by Aspen Plus software. Shortcut calculation was executed using three-column process to obtain initial parameters of Petlyuk column. In the initial parameters, rigorous calculation was executed by Multifrac-Petlyuk model and sensitivity model was used to optimize the parameters such as reflux ratio, feed stage, side product stage, connection stage and connection flow of the Peflyuk column. As an example, the separation of tri-component ethanol-propanol-butanol was simulated using a Petlyuk colunm. The results are as follows： plate number is 58 of main column and 29 ofpre-fractionator, feed stage based on pre-fractionator is 12, side product stage based on main column is 28, reflux ratio is 4.6. connection stage is 18 of main column to pre-fractionator＇s overhead and 47 of main column to pre-fractionator＇s bottom, liquid-phase reflux of main column to pre-fractionator＇s overhead is 65 kmol/hr and gas-phase reflux of main column to pre-fractionator＇s bottom is 145 kmol/hr. At these parameters, the product＇s mass fraction is 98.9% of ethanol, 98.7% of n-propanol and 99.0% of n-butanol, which all meet the requirement of the separation. The results of simulation and optimization will provide fundamental guide for the industrial design and production.