Advance Stripper Configuration for Energy-Saving Designs Using Standard Monoethanolamine Absorbent for Post-Combustion Carbon Capture

¹ Department of Chemical and Materials Engineering, Tunghai University, Taichung, Taiwan
² Green Energy and System Integration Research and Development Department, China Steel Corporation, Kaohsiung, Taiwan

^* Corresponding author: jialin@thu.edu.tw

Abstract

In a standard post-combustion carbon capture (PCC) process, the regeneration energy of the CO₂ lean solvent dominates the overall energy consumption. The energy reduction achieved by stripper modifications, such as the cold-split bypass, interheated stripper, and integration of both configurations, have been reported in the literature. In the cold-split bypass, the cold rich stream is split to recover the energy contained in the overhead vapor that was directly fed into the condenser in the traditional stripper configuration. The interheated stripper draws the semi-rich solvent from the middle of the stripper and exchanges heat with the hightemperature lean solvent from the reboiler; thereby, the overall column temperature can be raised that favors CO₂ desorption along the column. Therefore, the literature reported that the integrated modification, combining the cold-split bypass with the interheated stripper, takes both advantages of above modifications that can further reduce the energy requirement. However, the present work shows that energy-saving effect of integrated process is not as promising as the literature claimed. Once the feed stage of the warm-rich solvent is determined properly, the cold-split process can achieve the similar energy-saving performance as that achieved by the integrated process.