Effects of the Temperature Bulge in CO₂ Absorption from Flue Gas by Aqueous Monoethanolamine

Abstract

Pilot plant data for CO2 absorption by aqueous monoethanolamine (MEA) were simulated with the RateSep model and a dynamic model implemented in gPROMS. RateSep is the second generation rate-based model in AspenPlus. Because of the phenomena of combined absorption and water vaporization and condensation, a temperature bulge will appear in the absorber. The present study addresses the effects of column parameters including L/G, heat of absorption, height of packing, and flue gas CO2 concentration. The temperature bulge is quantified by its magnitude and location and how these parameters affect the absorber performance. When the bulge is located in the top or bottom of the column, the magnitude is close to the limiting values of the temperature in the liquid and gas, respectively, leaving the column. The magnitude is maximized when the bulge is located approximately in the middle of the column. The absorber performance seems to be independent of the bulge location when it is located in the top or in the bottom of the column, while it might affect the performance when located in the middle.

Dynamic simulation of MEA absorption process for CO2 capture from power plants

“…decreased). This behaviour was also reported by Kvamsdal and Rochelle (2008) for this process. The temperature bulge that occurred near the bottom of the absorber column for both case studies can be explained as follows: As the liquid flow downward the column, the CO 2 is transferred from the gas to the liquid phase.…”

“…The constants used in this equation are given in Table 3.10. (Kvamsdal and Rochelle, 2008;Kvamsdal et al, 2009;Lawal et al 2010), the dynamic model developed in this work was also implemented in gPROMS. Also, gPROMS is also a suitable tool to conduct controllability studies.…”

Demonstration of a post-combustion carbon capture pilot plant using amine-based solvents at the Łaziska Power Plant in Poland

“…The lean solution that entered the absorber was cooled to 40°C during both tests, and the highest temperature in absorber (the temperature bulge) reached approximately 60 and 75°C for tests 20 and 2, respectively. As the CO 2 was absorbed in the solvent, the temperature in the incoming solvent increased (Kvamsdal and Rochelle 2008). The temperature increase clearly indicated the exothermic effect of CO 2 absorption with MEA.…”

Current status and future development of solvent-based carbon capture

“…Dynamic models of stand-alone absorber (Posch and Haider 2013;Kvamsdal et al 2009;Kvamsdal and Rochelle 2008;Khan et al 2011;Lawal et al 2009a) and stand-alone stripper (Lawal et al 2009b;Zaii et al 2009) which are the main components of the PCC process based on chemical absorption are available in literature. The dynamic models of the complete process including the absorber and stripper are also available (Lawal et al 2010;Harun et al 2011;Gáspár and Cormoş 2011;MacDowell et al 2013;Flø et al 2015).…”