变压精馏分离乙腈-乙醇共沸物的模拟与优化  

Simulation and Optimization of Pressure-swing Distillation for Separating an Acetonitrile-ethanol Azeotrope

作　　者：仲超 李春梅 朱雅楠 Zhong Chao;Li Chunmei;Zhu Yanan(Nanjing Changjiang Jiangyu Environmental Protection Technology Co.,Ltd.,Nanjing 210047,China)

机构地区：[1]南京长江江宇环保科技股份有限公司,江苏南京210047

出　　处：《山东化工》2024年第11期202-206,共5页Shandong Chemical Industry

摘　　要：以Wilson活度系数模型为物性计算方法,使用Aspen Plus软件对变压精馏分离乙腈-乙醇常压共沸物的工艺进行模拟与优化。选择250和101.325 kPa作为加压塔和常压塔的操作压力,并在乙腈及乙醇产品纯度均为99.9%(质量分数)的约束条件下,重点考察了两塔理论板数对塔板温度分布以及进料板位置、回流比对两塔再沸器总热负荷的影响,得到了优化的工艺参数。优化后的工艺参数为:加压塔理论塔板数15、进料板位置5、回流比1.4;常压塔理论塔板数14、进料板位置5、回流比1.2。以此为基础,分析了常规变压精馏和热集成变压精馏的工艺能耗。结果表明:与常规变压精馏工艺相比,热集成变压精馏工艺可节能41.69%。The Aspen Plus software was utilized to simulate and optimize a pressure-swing distillation process for the separation of the atmospheric azeotrope in the acetonitrile-ethanol system,using the Wilson activity coefficient model for physical property calculations.The operating pressures for the pressurized and atmospheric columns were respectively chosen as 250 and 101.325 kPa.The temperature profiles of the trays in both columns were examined for different numbers of theoretical trays,with a focus on evaluating the impact of feed tray locations and reflux ratios on the total heat duty of the two reboilers while ensuring a purity level of 99.9%for both acetonitrile and ethanol products.Subsequently,the optimum process parameters were determined as follows:for the pressurized column,there are 15 theoretical trays,with the feed tray located at the 5th tray,and a reflux ratio of 1.4;for the atmospheric column,there are 14 theoretical trays,with the feed tray located at the 5th tray,and a reflux ratio of 1.2.Based on these optimization results,the energy consumption of both the conventional and heat-integrated pressure-swing distillation processes was analyzed.The results indicate that the heat-integrated pressure-swing distillation process saves 41.69% of energy compared with the conventional process.

关 键 词：变压精馏 乙腈 乙醇 分离 模拟 

分 类 号：TQ028.3[化学工程]