A novel kind of multiple steady states characteristics in the dividing wall column

doi:10.1016/j.cjche.2018.10.003

Abstract

Abstract: In this article, one kind of multiple steady states (MSS) phenomenon was investigated for a dividing wall column (DWC). The four-section model constructed in Aspen Plus was employed to simulate two DWC cases:mixture of n-hexane, n-heptane and n-octane; system of methanol, ethanol and n-propanol. It can be seen that there is a range of vapor split ratio in which multiple solutions of reflux ratio exist for fixed DWC configuration with the same feed and product streams. The width and the curve shapes of the MSS region, and the number of solutions change with the liquid split ratio. This MSS phenomenon was further explained using the component recovery around the prefractionator and the component recycling flow inside the DWC. This MSS phenomenon is helpful for DWC design by knowing the probable existence of multiple solutions in advance.

Key words: Dividing wall column, Multiple steady states, Vapor split ratio, Liquid split ratio, Recycling flow

摘要： In this article, one kind of multiple steady states (MSS) phenomenon was investigated for a dividing wall column (DWC). The four-section model constructed in Aspen Plus was employed to simulate two DWC cases:mixture of n-hexane, n-heptane and n-octane; system of methanol, ethanol and n-propanol. It can be seen that there is a range of vapor split ratio in which multiple solutions of reflux ratio exist for fixed DWC configuration with the same feed and product streams. The width and the curve shapes of the MSS region, and the number of solutions change with the liquid split ratio. This MSS phenomenon was further explained using the component recovery around the prefractionator and the component recycling flow inside the DWC. This MSS phenomenon is helpful for DWC design by knowing the probable existence of multiple solutions in advance.

关键词: Dividing wall column, Multiple steady states, Vapor split ratio, Liquid split ratio, Recycling flow

Erwei Song, Zengxi Li, Erqiang Wang. A novel kind of multiple steady states characteristics in the dividing wall column[J]. Chinese Journal of Chemical Engineering, 2019, 27(4): 869-876.

Erwei Song, Zengxi Li, Erqiang Wang. A novel kind of multiple steady states characteristics in the dividing wall column[J]. 中国化学工程学报, 2019, 27(4): 869-876.

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