Ipsakis D., Papadopoulou S., Voutetakis S., Seferlis P., 2013, Analysis and Implementation of a Plant-Wide Control System for an LPG Reforming-Fuel Cell Power System, Chemical Engineering Transactions, 35, 955-960.
The core aim of this study is the development of a plant-wide control system for a pilot plant scale power unit based on LPG fuel processing. The system consists of the LPG steam reformer for the production of hydrogen followed by a water-gas-shift reactor, both of fixed-bed geometry. A polymer electrolyte membrane (PEM) fuel cell utilizes the reformer’s hydrogen and enables power generation and delivery to a lithium-ion (Li-Ion) accumulator, thus simulating in this way a compact vehicular-oriented application. Heat integration in the system is achieved through a heat exchanger network mainly consisted of a burner that exploits the anode unconverted hydrogen and uses an individual LPG feed and a series of air coolers that enable efficient system autonomy. The main control objectives are the minimization of the system start-up time, the elimination of temperature overshoots in the reforming and water-gas-shift reactors as well as the effective alleviation of process disturbances during operation (mainly due to reaction thermal imbalances and catalyst deactivation). A multi-loop digital plant-wide control scheme utilizing PID controllers is proposed and tuned for optimal control error under several dynamic scenarios associated with the control objectives. Dynamic performance assessment of the control scheme is achieved through simulated cases utilizing a dynamic non-linear mathematical model for the integrated system. The proposed control scheme performed successfully under reference trajectory tracking and disturbance rejection scenarios.
