Overall efficiency analysis of the post-combustion CO2 capture using aqueous solution of amines

PATRICIA MORES; NICOLÁS SCENNA; SERGIO MUSSATI

CHEMICAL ENGINEERING SERIES - CO2 capture

Science Network

Año: 2011; p. 29 - 52

This chapter deals with the optimization of the post-combustion CO2 capture using a monoethanolamine (MEA) solution. The overall efficiency of the whole capture process is optimized using a detailed NLP mathematical model. The proposed model takes into account the effect of equilibrium reactions on the mass transfer, thermodynamic non-idealities and the hydraulics of the random packing. Specific correlations to compute enthalpies, fugacity coefficients, surface tension and effective interfacial area for mass transfer are also considered. The following are some of the main process variables which are optimized simultaneously: temperature, composition and flow-rates profiles of liquid and flue-gas streams along the column, heat duties in the reboiler, condenser and heat exchangers, electricity consumed by pumps and compressors. The main goal is to obtain a set of optimal thermodynamic solutions useful to establish valuable relationships between the most important process variables in order to find optimal economic solutions. Thus, the optimization results presented in this chapter can be then used to obtain basic relationships between thermodynamic and economic solutions. Certainly, the set of thermodynamic solutions may be efficiently used in a first phase to get systematically initial feasible solutions and bounds to guarantee the convergence of economic optimization problems.