Carbon dioxide capture processes: Simulation, design and sensitivity analysis

Carbon dioxide is the main greenhouse gas and its major source is combustion of fossil fuels for power generation. The objective of this study is to carry out the steady-state sensitivity analysis for chemical absorption of carbon dioxide capture from flue gas using monoethanolamine solvent. First a consistent simulation of the process verifying a base case design has been performed.

Available commercial simulation package Aspen Plus 7.2 is used for the steady state simulations. An equilibrium based model for the process simulations together with the electrolyte-NRTL model for the vapor liquid equilibrium and associated property models are used. Simulations are performed to investigate the sensitivity of the process variables to change in the design variables including process inputs and disturbances in the property model parameters.

Results of the sensitivity analysis on the steady state performance of the process to the L/G ratio to the absorber, CO2 lean solvent loadings, and striper pressure are presented in this paper. Based on the sensitivity analysis process optimization problems have been defined and solved and, a preliminary control structure selection has been made.