Analysis of mass transfer coefficient of CO2 absorbed by two-component amine mixture in a packed bed column

Abstract

Nowadays, coal fired plant has an important role in generating energy all over the world. It affects to greenhouse gases effect (GHGs) and global warming. Carbon dioxide (CO2) is a product of coal combustion that is the amount of number one in the world. However, most of the CO2 usually remove from post-combustion process by chemical absorption which is Monoethanolamine (MEA). Anyway, MEA has a disadvantage such as low CO2 loading and corrosion. Therefore, this study needs to investigate the effect of the mass transfer for a new solvents, 2-(Methylamino)ethanol (2-MAE) and Dimethylaminoethanol (DMAE), compensate for the drawbacks of MEA to increase in mass transfer rate and performance of CO2 absorption. Effect of amine concentration by varying weight ratio from 30:0 to 0:30 wt%, liquid flow rate 5.3,10.6 and 15.9 m3/m2•h, CO2 content in gas phase 5,10 and 15 %v/v, CO2 initial loading 0.0, 0.1 and 0.2 mol/mol were investigated. From the results, increasing the ratio of 2-MAE in mixed solution increases the highest mass transfer rate and CO2 absorption performance. On the other hand, increasing the ratio of DMAE decreases the mass transfer rate. The most influencing factor for mass transfer is the flow rate of solution that improves the forward rate of reaction and reduced time for dissolved CO2. However, two-component of amine solution can improve the drawback of a single-component very well. It can be seen that a new solvent will be useful in the future.