A biphasic CO₂ absorption (BiCAP) technology developed at the Illinois State Geological Survey (ISGS) has been selected for development and bench-scale testing by the U.S. Department of Energy (DOE) as a transformation technology for post-combustion carbon capture.

The BiCAP technology is enabled by a proprietary new class of water-lean, phase change solvents developed by ISGS researchers that allows the formation of dual liquid phases, with the absorbed CO₂ enriched in one phase used for solvent regeneration with a significantly reduced solvent mass. The technology features a novel process comprising multiple stages of phase separation and CO₂-rich phase removal during CO₂ absorption to maintain a high CO₂ absorption rate and a unique CO₂ stripping configuration to further reduce process heat duty.

Post-combustion carbon capture at power plants is expensive at present. State-of-the-art capture technologies will result in a ~80% increase in cost of electricity, which translates to a cost of ~$50 tonne of CO₂ captured. The majority of the cost (>60%) is attributable to power plant parasitic power loss due to carbon capture. According to project principal investigator Yongqi Lu, the BiCAP technology is targeted at reducing the parasitic power loss by ~40% and achieving a CO₂ capture cost of ~$30/tonne.

The proof-of-concept and lab-scale development of the BiCAP technology has been supported by the DOE (Award No. DE-FE0026434) since October 2015 to develop high-performance solvents, generate engineering data, and demonstrate the process concept.

“This new award by the USDOE will move the technology development forward via advancing solvent and process developments and testing the fully-integrated technology at a 40 kWe bench-scale with simulated flue gas in lab and with actual coal-derived flue gas at a power plant,” said Lu.

The project will be implemented in the following three years. The estimated $3 million project is one of six recently selected by the DOE under the Office of Fossil Energy’s Novel and Enabling Carbon Capture Transformational Technologies funding opportunity announcement.

Project partners include the Illinois Sustainability Technology Center for providing solvent and degradation product analysis and an Environmental, Health & Safety Risks assessment and Trimeric Corporation for bench-scale equipment design and a techno-economic analysis. Both teams joined the ISGS in the previous lab-scale development: the Illinois Sustainability Technology Center conducted solvent stability and corrosion effect assessments and Trimeric Corporation led a preliminary techno-economic analysis.

For more information contact: Yongqi Lu, yongqilu@illinois.edu, 217-244-4985.