GOMES, T. N.; http://lattes.cnpq.br/5950047053582955; GOMES, Thassio Nóbrega.
Abstract:
The integration of stirring systems in the calculation and optimization procedures has
suffered a significant lack of attention, what it can reflect in the results because such
systems provide an additional energy to the process, besides promote a better
distribution of mass and energy. This is meaningful for the reactive systems,
particularly for the Continuous Stirred Tank Reactor (CSTR), for which the key
variables and parameters, as well as the operating conditions of stirring systems can
play a pivotal role. Neglected these factors can lead to sub-optimal results as can be
observed in the literature. It is also well known that the sole use of the First Law of
Thermodynamics as an optimization tool can not yield expected results, hence the joint
use of the First and Second Laws condensed into a procedure so-called entropy
generation minimization (EGM) has shown itself able to drive the system towards better
results. Therefore, the main objective of this thesis is to determine the effects of key
parameters of the stirring system in the optimization procedures by means of EGM
applied to the reactive and non reactive systems. Such considerations have been
possible by dimensional analysis according to Rayleigh and Buckingham's method,
which takes into account the physical and geometric parameters and the variables of
the reactive system. Consider for the simulation purpose the production of propylene
glicol, the results have shown a significant increase in the conversion rate from 36%
(not-optimized system) to 95% (optimized system) with a consequent reduction of byproducts.
In addition, it has been possible to establish the influence of the work of the
stirrer in the optimization procedure for the reactive and non reactive systems. The
results also indicate that the use of the entropic analysis as optimization tool has been
proved to be simple, easy to apply and requiring low computational effort.