Plantwide optimization coupled with column sequencing and stacking using a process simulator automation server

• Published in: Computers & chemical engineering Vol. 146; p. 107196
• Main Authors: Ni, Yuan-Wei, Lin, Wei-En, Tang, Wei-Ting, Ward, Jeffrey D.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2021
• Subjects: Column stacking; Distillation column sequence; Heat integration; Plantwide optimization; Simulated annealing algorithm; Simulated annealing algorithm; Plantwide optimization; Column stacking; Heat integration; Distillation column sequence
• ISSN: 0098-1354; 1873-4375
• DOI: 10.1016/j.compchemeng.2020.107196

A method is proposed for plantwide process design and optimization that solves the column sequencing and stacking problems while also accounting for the tradeoff between reactor system design and separation system design. The plantwide process is represented by two flowsheets in a process simulator. One flowsheet represents the reactor network and the other flowsheet contains a single distillation column which is used to optimize each column in every sequence. When reactor design variables are specified, the reactor effluent flowrate and composition can be determined by simulating the reactor network flowsheet. Since the outlet from the reactor network is the feed to the separation system, the optimal separation system for this feed can then be designed. Finally, by looping over reactor design variables, a nearly-optimal plantwide process design can be determined. This permits plantwide optimization accounting for tradeoffs between the reactor section and separation section of a process while using rigorous modeling of both parts of the flowsheet. The rigorous models can still be constructed rapidly using commercial process simulation software. The method is illustrated with two case studies: the butane alkylation process and the cumene process.