Capture of CO₂ from Steam Reformer Flue Gases Using Monoethanolamine: Pilot Plant Validation and Process Design for Partial Capture

Carbon dioxide (CO 2 ) capture from a slipstream of steam reformer flue gas (18-20 vol % wet CO 2 ) using 30 wt % aqueous monoethanolamine was performed for 500 h in a mobile test unit (120 kg CO 2 /h). Specific reboiler duties (SRDs) of 3.6-3.8 MJ/kg CO 2 were achieved at 90% capture. The pilot data validate the modeling of off-design partial capture, that is, operation at lower CO 2 capture rates (at constant gas flow) than the absorption column was designed to achieve. This paper demonstrates that off-design partial capture enables significant energy savings (SRD, cooling) relative to on-design capture. The accrued savings depend on the column design (packing height, flooding approach) and the feed CO 2 concentration. Finally, a concept for stepwise deployment of carbon capture and storage in industries with high-CO 2 concentration sources (e.g., steel and cement manufacturing and refining) is introduced. Thanks to its inherent full-capture-ready design, the initial energy-efficient, off-design partial capture operation can be extended to full capture over time.