INVESTIGADORES
FRANCESCONI Javier Andres
artículos
Título:
Start-up of Homogeneous Azeotropic Distillation Columns with Multiple Steady States
Autor/es:
NICOLÁS J. SCENNA; SONIA J. BENZ; JAVIER A. FRANCESCONI; NESTOR H. RODRIGUEZ
Revista:
INDUSTRIAL & ENGINEERING CHEMICAL RESEARCH
Referencias:
Año: 2004 vol. 43 p. 553 - 565
ISSN:
0888-5885
Resumen:
The impact of different start-up procedures on the behavior
of two azeotropic distillation columns with multiple steady states is analyzed.
Several dynamic simulation results for the two study cases are presented.
Through an examination of the profile evolutions corresponding to given open-loop
start-up policies (manual start-up strategies), it can be seen how the column
arrives at different steady states as a function of the start-up policy. This
shows that it is possible to identify a set of critical values for supervision
of the start-up. Also, guidelines of general validity are given with the aim of
finding the appropriate start-up policy for obtaining a desired solution. A
mechanistic (qualitative) approach is presented for the interpretation of the
system behavior. Some connections among the system responses and the phenomenon
of multiplicity are presented. Also, a quantitative, semiempirical relationship
is introduced to corroborate the qualitative explanation of the system
responses. Finally, closed-loop start-up policies using a simple PI controller
are analyzed, showing that the desired steady state can always be achieved in
these cases.