Simulation of CO2 capture using MEA scrubbing: a flowsheet decomposition method

This paper presents a method of decomposing the flow sheet that assists in converging the process flow sheet and in optimizing key process operating variables, in particular the amine loadings and temperature of MEA entering the stripper. This method was applied to three different CO2 concentrations (molar fraction, wet basis): 3% (to simulate flue gas from a gas turbine), 14% (flue gas from a coal plant) and 25% (flue gas from a cement plant). The decomposition method proved useful for investigation of the process parameters in both the absorber and the stripper. The results from the decoupled flow sheet provided good initial estimates for the convergence of the integrated flow sheet. The results from the decoupled and integrated flow sheets were similar. A minimum reboiler duty was found at a lean MEA loading of 0.25 for all CO2 concentrations studied.