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| Author(s): |
Wilson Hideki Hirota
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2009-09-01 |
| Examining board members: |
Reinaldo Giudici;
Ana Maria Frattini Fileti;
Fábio Bentes Freire;
Liliane Maria Ferrareso Lona;
Claudia Sayer
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| Advisor: | Reinaldo Giudici; Claudia Sayer |
| Abstract | |
The increasing demand for the production of polymers with more tight properties has placed great emphasis on the development of accurate and robust online monitoring techniques of polymerization reactions. Unfortunately, most of the main characteristics are not measurable online from analytical methodologies currently available and, therefore, in practice, the final properties of polymer latexes are obtained through off line characterization of discrete samples collected from the process, resulting in measurement delay which is undesirable for real-time control. On the other hand, since most of the polymerization reactions are highly exothermic, it is possible to quantify continuously the heat release rate based on temperature measurements and energy balance equations that, in turn, can be used to infer valuable information about the state of process. However, this approach requires up-dating the value of the global heat exchange coefficient through reaction, once this parameter is subject to significant time variations. Therefore, this work aims to examine the feasibility of joint implementation of the concepts of reaction calorimetry and nonlinear state observers for estimation of the states of a chemical process. In order to do that, two distinct chemical reactions will be considered: a) a hydrolysis of acetic anhydride reaction, b) an emulsion copolymerization reaction. The results showed that this approach shows a strong dependence of the tuning parameters, preventing its use for online monitoring of a chemical process. On the other hand, applying the heat balance it is possible to infer continuously the heat release rate and the states of polymerization reactions. (AU) | |
| FAPESP's process: | 06/01133-0 - Online estimation and control of polymer latex properties via calorimetric techniques |
| Grantee: | Wilson Hideki Hirota |
| Support Opportunities: | Scholarships in Brazil - Doctorate |