>From ccyu@ch.ntust.edu.tw Mon Feb 02 06:11:19 1998

Prost-Seminar 04 Mar 1998.

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Reactor/Separator Processes with Recycle:
Design for Composition Control
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Cheng-Ching Yu 

Dept. of Chemical Engineering,
National Taiwan University of Science and Technology
Taipei, TAIWAN 106,

Abstract

The balanced control scheme has the advantage of alleviating
the snowball effect for plant with recycles. 
However, by fixing intensive variables, the control 
scheme leads to rather complex control configurations,
especially for composition control. Based on disturbance
sensitivity analyses, we are able to simplify the 
control structure by eliminating some of the compositions
loops and yet maintaining the balance  a partial composition
control approach. More importantly, this is achieved 
with minimal process information, i.e., material balances
or, simply, characteristics of the balanced scheme. 
Results show that we only need one composition loop to
keep all three compositions at set points. Nonlinear 
simulations show that effective composition control is 
obtained with rather simple control structure.

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Cheng-Ching Yu                                ccyu@ch.ntust.edu.tw
Department of Chemical Engineering            Tel: +886-2-2737-6620
National Taiwan University of Sci. Technol.   Fax: +886-2-2737-6644
43, Keelung Rd., Sec. 4
Taipei, TAIWAN 106
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