Mathematics in Chemical
Kinetics and Engineering
2004 Annual Seminar
Welcome to the 2004 annual seminar on Mathematics in Chemical
Kinetics and Engineering, to be held at Ghent University,
Belgium on April 28th, 2004!
The Laboratory for Petrochemical Technology (LPT) and
the Research Group for Numerical functional analysis and
Mathematical Modelling (NfaM2) of Ghent
University are pleased to invite you to attend the annual
seminar on "Mathematics in Chemical Kinetics and Engineering"
which will be held on April 28th, 2004 in Ghent, Belgium.
After the successful international Mackie-2002 conference
and Mackie-2003 Annual Seminar held at Ghent University, the
local organizers have again invited two world-class experts
from the fields of mathematics and chemical engineering, Prof.
Pierre Rouchon (École des Mines de Paris) and Prof. S.
Pushpavanam (I.I.T Madras), to give seminar talks during a
Participation to the seminar is free, but registration is
requested AS SOON AS POSSIBLE (simply register by sending
e-mail to email@example.com). A complimentary lunch is
offered to the participants at the venue.
- 10:00 Coffee and registration
- 10:45 Introduction
- 11:00 Pierre Rouchon on Invariant estimation and
control of a polymerization reactor
- 12:00 Question time and discussion
- 12:30 Lunch
- 14:30 S. Pushpavanam on Modeling and Simulation of
Coupled Non-Linear Systems
- 15:30 Question time and discussion
- 16:00 Concluding remarks and closing address
- "Invariant estimation and control of a polymerization
reactor" by Pierre Rouchon and Nasradine Aghannan, of the
Centre Automatique et Systèmes, École des Mines
de Paris, France.
The industrial project concerns the reactor PP2
(polypropylene) on the petrochemical plant of Feluy
(Belgium). The objectives consist in increasing the
productivity while maintaining a better stability for the
polymer quality. In this order, we have developed new
regulators to control better the principal variables defining
the reactors content, which are at the heart of these
production plants. First, our task was to establish a model
to represent the reactors dynamics, and then from this model
we have designed soft sensors to estimate the key variables
and designed the controller laws. On-line data illustrate the
interest of obtained results.
While working on this project, we faced the question
concerning the choice of the units in which we had to write
the equations. We were concerned by writing algorithms
independent of this choice as the reactors dynamics is. This
questioning is at the origin of a new point of view on
parameter estimations and observer design. Our major
contribution lies in an invariant way to measure the
estimation errors. Under some assumptions, the construction
of such invariant errors can be done explicitly via Cartan's
moving frame method. We illustrate these concepts on the
polymerization reactor models those equations are invariant
with respect to the transformations group associated to unit
- "Modeling and Simulation of Coupled Non-Linear Systems",
by S. Pushpavanam of the Department of Chemical Engineering,
I.I.T Madras, India.
The design of individual units such as reactors and
separators has been investigated extensively. When the
processes occurring in these units are non-linear these
systems exhibit different kinds of exotic behavior. For
example autocatalytic reactions and non-isothermal reactions
occuring in CSTR?s are known to exhibit multiple
steady-states and sustained periodic oscillations. Similar
behavior has been reported for separation processes such as
distillation columns under specific control strategies.
In a typical process flow sheet a reactor is coupled to a
downstream separator via a recycle stream when the conversion
in the reactor is low. Such processes occur for example in
the manufacture of ammonia, methanol. The recycle stream is
the reactant rich stream from the separator. This coupling
ensures that the downstream separator can affect the
performance of the upstream reactor.
The effect of this coupling is studied using a CSTR to model
the reactor and a flash or distillation column to model the
separator. The operation of the separator constrains the
performance of the coupled system. It is established that
there are regions of high feed rates when the system has no
feasible steady solution. The performance of the system for
different control strategies is discussed.
Applications of singularity theory for analysis of steady
state behavior and bifurcation theory for dynamic behavior
enable us to obtain a comprehensive understanding of the
coupled system. Analytical and semi-analytical results will
be analysed to appreciate the understanding of the behavior
of the coupled system
One important feature is that the coupling induces a delay
or a transportation lag from one unit to the other. The
effect of this delay on the system behavior is studied when
the delay arises in the recycle stream or in the stream from
the reactor to the separator. It is found that delay renders
a control strategy, which is otherwise favorable unfavorable
and vice versa.
Our efforts towards developing of a generalised approach to
understand the behavior of these coupled reactor separator
systems will be dwelt upon.
The annual seminar on Mathematics in Chemical Kinetics and
Engineering will be held in the Pand, a renovated ancient
building owned by Ghent University, and situated in the heart
of Ghent's historical centre (address: Onderbergen 1).
Tourist Attractions in Ghent
Belgium possesses a wealth of highly distinctive architectural,
cultural and gastronomic traditions.
Ghent, founded in the 10th century AD, has today a
population of over 200 thousand. The official language is
Dutch; knowledge of English is very widespread.
Major touristic attractions include the Gothic Cathedral and
other medieval churches, the Van Eyck Altarpiece depicting the
Adoration of the Mystic Lamb, the City Museum of Contemporary
Art (SMAK), and numerous shops selling Flemish specialities
such as local beers, lace and many other renowned products of
Late April is Spring in Ghent, with average temperature of 15
degrees Celsius. Some rain is to be expected.
You can register by sending e-mail to
firstname.lastname@example.org. Please also state if you want lunch
(complimentary) at the venue. (An adapted menu can be obtained
for special requirements, e.g., vegetarian.)
For the latest information, consult the annual seminar's Web
site at www.mackie-workshops.com
Denis Constales - email@example.com - http://cage.UGent.be/~dc/index-world.html