SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2021, Vol. 29 ›› Issue (1): 67-76.DOI: 10.1016/j.cjche.2020.07.059

• Separation Science and Engineering • Previous Articles     Next Articles

Dynamic control analysis of interconnected pressure-swing distillation process with and without heat integration for separating azeotrope

Jingwei Yang1, Zhengkun Hou1, Yao Dai1, Kang Ma1, Peizhe Cui1, Yinglong Wang1, Zhaoyou Zhu1, Jun Gao2   

  1. 1 College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China;
    2 College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
  • Received:2020-06-04 Revised:2020-06-29 Online:2021-04-02 Published:2021-01-28
  • Contact: Yinglong Wang
  • Supported by:
    This work is supported by the National Natural Science Foundation of China (No.21776145 and 21676152).

Dynamic control analysis of interconnected pressure-swing distillation process with and without heat integration for separating azeotrope

Jingwei Yang1, Zhengkun Hou1, Yao Dai1, Kang Ma1, Peizhe Cui1, Yinglong Wang1, Zhaoyou Zhu1, Jun Gao2   

  1. 1 College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China;
    2 College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
  • 通讯作者: Yinglong Wang
  • 基金资助:
    This work is supported by the National Natural Science Foundation of China (No.21776145 and 21676152).

Abstract: Dynamic controls of pressure-swing distillation with an intermediate connection (PSDIC) process of ethyl acetate and ethanol separation were investigated. The double temperature/composition cascade control structure can perfectly implement effective control when ±20% feed disturbances were introduced. This control structure did not require the control of the flowrate of the side stream. The dynamic controllability of PSDIC with partial heat integration (PHIPSDIC) was also explored. The improved control structure can effectively control ±20% feed disturbances. However, in industrial production, simple controller, sensitive and easy to operate, is the optimal target. To avoid the use of component controllers or complex control structure, the original product purities could be maintained using the basic control structure for the PSDIC process if the product purities in steady state were properly increased, albeit by incurring a slight rise in the total annual cost (TAC). This alternative method without a composition controller combined with the energy-saving PSDIC process provides a simple and effective control scheme in industrial production.

Key words: Azeotrope, Pressure-swing distillation, Dynamic controllability, Control structure

摘要: Dynamic controls of pressure-swing distillation with an intermediate connection (PSDIC) process of ethyl acetate and ethanol separation were investigated. The double temperature/composition cascade control structure can perfectly implement effective control when ±20% feed disturbances were introduced. This control structure did not require the control of the flowrate of the side stream. The dynamic controllability of PSDIC with partial heat integration (PHIPSDIC) was also explored. The improved control structure can effectively control ±20% feed disturbances. However, in industrial production, simple controller, sensitive and easy to operate, is the optimal target. To avoid the use of component controllers or complex control structure, the original product purities could be maintained using the basic control structure for the PSDIC process if the product purities in steady state were properly increased, albeit by incurring a slight rise in the total annual cost (TAC). This alternative method without a composition controller combined with the energy-saving PSDIC process provides a simple and effective control scheme in industrial production.

关键词: Azeotrope, Pressure-swing distillation, Dynamic controllability, Control structure