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

Carbon dioxide (CO2) capture from a slipstream of steam reformer flue gas (18-20 vol %(wet) CO2) using 30 wt % aqueous monoethanolamine was performed for similar to 500 h in a mobile test unit (similar to 420 kg CO2/h). Specific reboiler duties (SRDs) of 3.6-3.8 MJ/kg CO2 were achieved at 90% capture. The pilot data validate the modeling of off-design partial capture, that is, operation at lower CO2 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 CO2 concentration. Finally, a concept for stepwise deployment of carbon capture and storage in industries with high-CO2 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.

Automated summary

This study demonstrates the successful capture of carbon dioxide from steam reformer flue gas using monoethanolamine. The off-design partial capture method proves to be energy-saving compared to on-design capture, and a concept for stepwise deployment of carbon capture and storage in high-CO2 concentration industries is introduced.