Adaptive Fuzzy Control for Rectification Process of Recycled Solvent

This paper deals with the development of an adaptive fuzzy control system for the rectification process of a recycled solvent (isoprene-isopentane-toluene fraction) using the Fuzzy Logic Toolbox expansion package for various critical operating situations. The main critical parameters included are the following: high or low temperature, high or low pressure, and high or low hydrocarbon level in the column bottom. To solve the problem of choosing a critical situation, a fuzzy controller for condition assessment was developed. This controller has two resulting outputs regarding the possible critical situations. The first output requires the need to use hot water as a heating agent. The second output requires the need to use steam as a heating agent. Depending on the output of the fuzzy controller for condition assessment, one of the two subsequent controllers is switched on. These were in advance set to certain values of input variables. The proposed method for controlling the process of continuous rectification of isoprene-isopentane-toluene fraction in a tray-type column will allow to timely detect the critical situations during system operation and take necessary measures to remove them, which ultimately will improve the product quality, increase plant capacity and save energy.