Carbon dioxide absorption by Ammonia-promoted aqueous triethanolamine solution in a packed bed

CO2 absorption by ammonia added triethanolamine aqueous solution as a promoter was investigated in terms of absorption percentage (AP), overall volumetric mass transfer coefficient (K(G)a(e)), and molar flux (N-A) in a packed column. Three variables of ammonia concentration (0-5 wt%), Triethanolamine concentration (10-30 wt%), and gas flow rate (1,500-2,500 ml/min) were considered as significant variables in absorption performance. Effect of these variables and their interactions were inspected using the three level factorial response-surface method. Statistical analysis of the results showed that an ammonia concentration with 72.99%, 71.83, and 81.12% has the greatest effect on AP%, N-A, and K(G)a(e), respectively. Then, gas flow rate with 5.27% and 3.90%, had a great effect on AP% and K(G)a(e), respectively. Finally, the optimal operating conditions were determined to maximize the responses. Under optimal operating conditions, the maximum values for AP%, K(G)a(e), and N-A were 98.94%, 0.202 kmol/h center dot m(3)center dot kPa, and 3.901 kmol/m(2)center dot h, respectively. Thus, adding ammonia to triethanolamine considerably improves the mass transfer performance of solvent.

Automated summary

The research investigated the CO2 absorption performance in triethanolamine aqueous solution with added ammonia as a promoter. The absorption percentage, overall volumetric mass transfer coefficient, and molar flux were studied. Ammonia concentration, triethanolamine concentration, and gas flow rate were considered as significant variables. The results showed that ammonia concentration had the greatest effect on absorption percentage, molar flux, and overall volumetric mass transfer coefficient. Gas flow rate also had a significant effect on absorption percentage and overall volumetric mass transfer coefficient. The study determined the optimal operating conditions to maximize the performance of the solvent.