Dynamic simulation of flash drums using rigorous physical property calculations

Brazilian Journal of Chemical Engineering. 2007;24(2):277-286 DOI 10.1590/S0104-66322007000200012

 

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Journal Title: Brazilian Journal of Chemical Engineering

ISSN: 0104-6632 (Print); 1678-4383 (Online)

Publisher: Brazilian Society of Chemical Engineering

LCC Subject Category: Technology: Chemical technology: Chemical engineering

Country of publisher: Brazil

Language of fulltext: English

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AUTHORS

F. M. Gonçalves
M. Castier
O. Q. F. Araújo

EDITORIAL INFORMATION

Peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 12 weeks

 

Abstract | Full Text

The dynamics of flash drums is simulated using a formulation adequate for phase modeling with equations of state (EOS). The energy and mass balances are written as differential equations for the internal energy and the number of moles of each species. The algebraic equations of the model, solved at each time step, are those of a flash with specified internal energy, volume and mole numbers (UVN flash). A new aspect of our dynamic simulations is the use of direct iterations in phase volumes (instead of pressure) for solving the algebraic equations. It was also found that an iterative procedure previously suggested in the literature for UVN flashes becomes unreliable close to phase boundaries and a new alternative is proposed. Another unusual aspect of this work is that the model expressions, including the physical properties and their analytical derivatives, were quickly implemented using computer algebra.