A Decentralized Control Structure for a CO2 Compression, Capture and Purification Process: An Uncertain Relative Gain Array Approach

Abstract This paper presents a study on decentralized control structures that can be proposed to control a CO 2 compression, capture, and purification process for fossil fuel power plants based on oxyfuel combustion. A dynamic model that describes the transient behavior of this process is currently not available. Thus, the present work applied the Relative Gain Array (RGA) analysis to identify the most promising control strategies for this process. The process gains were estimated using a steady-state process model developed in Aspen Plus and validated with data obtained from the CanmetENERGY. The RGA analysis performed for the base case operation of this process was compared to an uncertain RGA analysis that takes into account the uncertainty on the process gains for control structure selection. The result obtained with the uncertain RGA demonstrates that the controller pairings suggested by nominal RGA can lead to control configurations with loops that may become unstable.