Abstract 
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[eng] Process control is a particular domain of chemical engineering that is concerned with the dynamical behaviour of the process state (with the objective to design monitoring and control tools). Besides, process control uses also mathematics and more precisely dynamical system theory. But the mathematical tools that are used in system theory introduce abstract concepts for which the interpretation by the chemical engineer is difficult because he cannot relate them to the physical understanding of the process. After the step of modelling the chemical process using the thermodynamics, the underlying phenomena are more or less pushed aside, and the rest of the analysis is based on the mathematical model. However for the past decade a new approach which is based on the physics of the systems has been receiving a growing interest for the analysis and control of physical systems. It uses the relations between the physics and the mathematical tools to develop physics based control systems. More precisely it uses energy considerations or the dissipated power to control the dynamical behaviour.
In this framework, the main topic of this thesis is to integrate thermodynamic considerations into the analysis and the design of process control systems. Due to the central role of energy transfers and transformations, and of the second law on the evolution of the process state and hence on its dynamical behaviour, we want to interpret system theory results for chemical processes in terms of energy and entropy considerations. First we start from thermodynamic considerations on the system and try to relate them to tools from system theory. Then we develop a mathematical formalism that encompasses the thermodynamic fundamental laws. Both approaches lead to a better understanding of the influence of the physical phenomena on the characteristics of the dynamical behaviour of the system and consequently allow in the future to develop more efficient control systems that can act more specifically on the sources of the undesired behaviour.
