Statistical factorial design analysis for parametric interaction and empirical correlations of CO 2 absorption performance in MEA and blended MEA/MDEA processes

Abstract

A principle of statistical factorial design was applied to characterize behaviour of mass-transfer performance in the carbon dioxide (CO 2) absorption process using monoethanolamine (MEA) and blended MEA/methyldiethanolamine (MDEA) solutions. Over a hundred experiments were carried out using a bench-scale absorber packed with structured packing. The absorption performance was analyzed in terms of overall mass-transfer coefficient ( K G a e). The results show that CO 2 loading of the solution is the most influential process parameter on K G a e, followed by alkanolamine concentration, CO 2 partial pressure in feed gas, temperature, and liquid circulating rate, respectively. The temperature interacts with all tested process parameters. A mixing ratio between MEA and MDEA in the blended solution significantly affects K G a e. Second-order correlations for the prediction of K G a e were developed for both MEA and MEA/MDEA systems. A relative packing factor was derived as a function of packing surface area and eventually integrated into the developed mass-transfer correlations for the purpose of scale-up.