Fuzzy logic‐based optimal control of a catalytic reformer

Catalytic naphtha reforming is an important process carried out in refineries for upgrading low-octane naphtha to high-octane gasoline. A reformer can meet many product demands through its wide range of design and flexibility in operation. This work deals with fuzzy logic-based optimization of a catalytic reformer. This optimization requires an accurate process model that is valid over wide range of operating conditions. In this work, a simple kinetic model has been developed. This model gives the temperature and concentration profiles of three important hydrocarbons (naphthenes, paraffins, and aromatics) across the reactors. A fuzzy logic-based optimal control scheme has been developed to maximize the aromatics yield, subject to constraints in inlet temperature of the reactors. Four fuzzy logic systems, one in forward path and three in feedback path, have been developed to give setpoints for temperature control loops of the three reactors. Finally, the results are compared with the conventional control scheme and the better performance of fuzzy logic-based control is validated. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.