Applicability and validation of use of equilibrium-based absorber models with reduced stage efficiency for dynamic simulation of post-combustion CO2 capture processes

Abstract

Use of complex rate-based models for absorbers in a post-combustion CO2 capture process may lead to high computational complexity and simulation time. Method using reduced stage efficiency in equilibrium-based model for such columns may provide acceptable range of accuracy with comparatively much less simulation time and thereby enabling them to be used simultaneously with dynamic models of power plants. This paper discusses the applicability of such method and presents the validation of use of such methods using two pilot plant data at both steady state and transient operation. Steady state plant data were used to determine the reduced stage efficiencies for the pilot plants. The dynamic models with those stage efficiencies were simulated to predict both the steady state operation and transient operation under step change in solvent flow rate scenario with nominal deviations in a range of 3-6% in the simulation results with simulation time 35 times higher than the real-time.