A Hybrid Mechanism and Data-Based Modeling Approach to a Post-Combustion Carbon Capture Process in a Coal-Fired Power Unit

Chemical absorption carbon capture systems use solutions with complex compositions to further reduce energy consumption and improve performance. Modeling and simulation are essential methods for studying the characteristics of these systems and optimizing them. However, existing methods cannot be used to build models of systems with complex or unknown solutions. This study proposes a hybrid modeling method integrating mechanism modeling and operational data for a chemical absorption carbon capture system. This method interprets the physical and chemical properties of solvents under various operating conditions based on operational data. To validate the effectiveness of this method, it is applied to a real-life post-combustion carbon dioxide capture system in a 1000 MW coal-fired power unit, which has an annual capture capacity of 10,000 tons. The results of the case study indicate that the proposed method can obtain values of key property parameters of solvents, including absorption heat, cyclic carbon capacity, and heat capacity. The average relative error between operational data and simulation data ranges from 0.2% to 8.0%.