Dynamic modelling and control of MEA absorption processes for CO2 capture from power plants

This paper presents a mechanistic dynamic model of a post-combustion CO2 capture plant using the MEA absorption process. Insight regarding the process dynamics due to various changes in the plant's operating conditions is presented and three decentralized control structures are proposed. The first control scheme was designed using the RGA (Relative Gain Array) analysis whereas the other two control schemes were designed based on heuristics. The performance of the proposed control schemes was evaluated under different scenarios, e.g. changes in flue gas flow rates, set point tracking, and valve stiction. In this study, a control scheme obtained from the heuristic approach resulted in shorter closed-loop settling times than the RGA-based control scheme.