Results of Amine Plant Operations from 30 wt% and 40 wt% Aqueous MEA Testing at the CO2 Technology Centre Mongstad

Abstract

Abstract An amine plant campaign has been performed at the CO 2 Technology Centre Mongstad applying the aqueous 30 wt% and 40 wt% monoethanolamine (MEA) solvent systems for treatment of flue gas from a combined heat and power (CHP) plant. CHP flue gas flow rates were ranging from about 40.000 Sm 3 /h to 60.000 Sm 3 /h and the CO 2 content was about 3.5 vol%. Minimum specific reboiler duties (SRD) of respectively 4.0 MJ/kg CO 2 and 3.7 MJ/kg CO 2 were obtained for the aqueous 30 wt% MEA solvent system without and with the addition of anti-foam solution. A minimum SRD of 3.4 MJ/kg CO 2 was obtained for the aqueous 40 wt% MEA solvent system. Lower SRD and absorber liquid to gas (L/G) ratios were obtained with higher concentration MEA solvents. Increased absorber packing heights resulted in lower SRD. Variation in flue gas supply flow rates and corresponding variations in solvent flow rates, i.e. constant L/G ratios, did not yield any significant variations in SRD. Decreased flue gas supply temperatures resulted in lower SRD. For any future large scale post-combustion capture (PCC) amine plant, engineering aspects such as the flue gas supply temperature and instrumentation monitoring CO 2 content in the flue gas must be evaluated to avoid the chemical equilibrium pinch behavior. Engineering and environmental aspects related to the use of anti-foam solutions for future large scale PCC amine plants must also be considered.