Master's Dissertation
DOI
https://doi.org/10.11606/D.3.2007.tde-09082007-181813
Document
Author
Full name
Murilo Uliana
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2007
Supervisor
Committee
Giudici, Reinaldo (President)
Araujo, Pedro Henrique Hermes de
Guardani, Roberto
Title in Portuguese
Soluções de equação de balanço populacional pelo método de classes com aplicação a processo de polimerização em suspensão.
Keywords in Portuguese
Equações algébricas diferenciais
Modelagem matemática
Polimerização
Polímeros (química orgânica)
Abstract in Portuguese
Title in English
Solution of population balance equation using the method of classes applied to suspension polymerization process.
Keywords in English
Algebraic differential equations
Mathematical modeling
Polymerization
Polymers (organic chemistry)
Abstract in English
The mathematical modeling of suspension polymerization of styrene accounting for the population balance equation to predict the dynamic behavior of particle size distribution was studied. In this process, the population balance is determined by the rates of breakage and coalescence. Different methods for solving population balance (BP) equations were studied and, for the case of suspension polymerization, the numerical solution was obtained using the discretized BP by the method of classes and the fixed pivot technique. The effect of the number of discretization elements (number of classes) was investigated. In order to model the initial particle size distribution (PSD), which was not measured experimentally, an initial normal distribution with high average and low variance was assumed and the agitation process with breakage and coalescence was simulated until a constant PSD is reached. This PSD is then used as the initial condition for the process simulation. Simulation results were validated by comparison with experimental data taken from the literature. The first data set involves the dispersion process of styrene droplets in water, without polymerization. The second data set refers to the process of suspension polymerization of styrene carried out in a laboratory-scale batch reactor, in which the effects of agitation speed, amount of stabilizer (surface-active agent) and disperse phase holdup were studied. In both cases, the model was able to represent correctly the trends of the experimental data.