欢迎访问过程工程学报, 今天是

过程工程学报 ›› 2022, Vol. 22 ›› Issue (2): 249-257.DOI: 10.12034/j.issn.1009-606X.221022

• 研究论文 • 上一篇    下一篇

变压精馏分离丙酮和环己烷的动态特性

张春花1， 诸林1*， 吕利平2， 周倩1， 金仕胜1   

  1. 1. 西南石油大学化学化工学院，四川 成都 610500 2. 长江师范学院化学化工学院，重庆 涪陵 408000
  • 收稿日期:2021-01-22 修回日期:2021-05-07 出版日期:2022-02-28 发布日期:2022-02-28
  • 通讯作者: 诸林 zhulinswpi65@gmail.com
  • 作者简介:张春花(1996-)，女，重庆市人，硕士研究生，化学工程与技术专业，E-mail: zhangchunhuaswpu@126.com；诸林，通讯联系人，E-mail: zhulinswpi65@gmail.com.

Dynamics performance of pressure swing distillation for acetone and cyclohexane separation

Chunhua ZHANG1,  Lin ZHU1*,  Liping LÜ2,  Qian ZHOU1,  Shisheng JIN1   

  1. 1. College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China 2. College of Chemistry and Chemical Engineering, Yangtze Normal University, Fuling, Chongqing 408000, China
  • Received:2021-01-22 Revised:2021-05-07 Online:2022-02-28 Published:2022-02-28
  • Contact: Lin ZHU zhulinswpi65@gmail.com

PDF

摘要： 基于丙酮-环己烷共沸体系的压力敏感性，利用Aspen Plus软件，以年度总费用(TAC)最小为目标函数对常规、部分及完全热集成变压精馏工艺进行稳态模拟与优化，并以经济最优的完全热集成变压精馏工艺为基础，借助Aspen Plus Dynamics软件建立多种不同控制结构，通过改变进料流量和进料组成考察了控制结构的有效性，并提出塔底热负荷/进料量比例控制与组成-温度串级控制相结合的改进控制结构。稳态模拟与优化结果表明，常规、部分和完全热集成三种工艺的最小TAC分别为3.64×105, 2.83×105, 2.76×105 $/y，经济最优工艺为完全热集成变压精馏。动态响应结果表明固定回流量/进料量控制结构在响应时间方面优于固定回流比控制结构，但产品纯度未达到设计值99.9wt%；而塔底热负荷/进料量比例控制与组成-温度串级控制相结合的改进控制结构能够有效保证产品纯度在99.9wt%及以上。

关键词: 丙酮, 环己烷, 变压精馏, 热集成, 动态

Abstract: As significant chemical raw material and solvent, acetone and cyclohexane are widely applied in chemical industry. However, the mixture of them will form a minimum boiling homogeneous azeotrope at atmospheric pressure, which severely hinders the separation of them. Based on the advantages of pressure swing distillation (PSD) and the pressure sensitivity of the azeotropic mixture of acetone and cyclohexane, the investigation of the design and the simulation of PSD are implemented by Aspen Plus software. The results show that the purity of products achieve 99.9wt%. In order to save the total annual cost (TAC) and energy, based on the heat integration technology and economic optimization, it is implemented that the process enhancement with the minimum TAC as objective function. Furthermore, the TAC of the steady-state process of conventional, partial and full heat integration PSD are 3.64×105, 2.83×105, 2.76×105 $/y, respectively. Compared with the conventional PSD, the economic reduction rate of partial and full heat integration are 22.36% and 24.18%, respectively, and the full heat integration is most economical. In view of these, the different control structures are established by Aspen Plus Dynamics, and the anti-disturbance performance is investigated by changing the feed flow rate and composition, the dynamic performance of the full heat integration PSD process is assessed. The dynamic response results indicate that the control structure with a fixed reflux-to-feed flow rate ratio is better than the control structure with a fixed reflux ratio in terms of settlement time. However, the control structure with a fixed reflux-to-feed flow rate ratio cannot maintain product purity, up to the design value of 99.9wt%. For meet the goal of the requirements of products purities, an improved control structure with feed forward proportional (reboiler heat duty to feed flow rate ratio) control and composition-temperature cascade control are proposed, which can effectively ensure that the product purity reaches more than 99.9wt%.

Key words: acetone, cyclohexane, pressure swing distillation, heat integration, dynamics.