This project focuses on the modelling of industrial equipment and controllers. The modelled devices consist of a polymerization reactor and a heat exchanger while the temperature is controlled. Since the regulated system is unstable, the model identification can only be performed with the presence of active control. This refers to modelling based on process data (stochastic approach) and physicochemical characteristics (deterministic approach). Both approaches are actively used in practice, and through statistical analysis of the obtained data, I will be able to verify the correctness of the setting of process controllers, including their improvement, without the need to intervene in real devices. The acquired results will be tested in laboratory conditions and on data from our industrial partner - Slovnaft, a.s., Bratislava. The results of the project will be made publicly available in the form of open-source software packages to process engineers and operators in the industry.