COMPACT ABSORBER TECHNOLOGY LEADS TO SIGNIFICANT REDUCTION IN THE COST OF POINT SOURCE CO₂ CAPTURE

The size of columns in traditional absorption-based processes for CO₂ capture contributes significantly to the overall capital cost. A demonstrated method to reduce the cost of point source CO2 capture, focusing on reducing the absorber height by increasing the liquid-to-gas reaction contact area and decreasing the CO2 diffusion resistance without increasing gas-side pressure drop is presented along with techno-economic analysis results. Bench-scale tests on the unique Compact Absorber showed overall CO2 mass transfer enhancement of varying degrees compared to a traditional packed column for similar process conditions, demonstrating that a +60% reduction in size of a typical postcombustion absorber with a packing height of 70–100 ft and total height of 150–180 ft can be achieved. The techno-economic analysis showed significant cost reductions when the Compact Absorber is combined with other transformative aspects of the University of Kentucky Institute for Decarbonization and Energy Advancement point source CO₂ capture process compared to the US Department of Energy, National Energy Technology Laboratory pertinent reference case for pulverized coal plants with CO2 capture. A levelized cost of electricity excluding CO₂ transportation and storage of 95.6/MWh was estimated, which is a 9% reduction, with a total capital cost contribution of 45/MWh, which is a 12% reduction. Additionally, a breakeven CO₂ sales price, also referred to as the cost of CO₂ capture, of 36.70/tonne was estimated when the University of Kentucky hindered primary amine solvent is used, which is a 20% reduction compared to the reference case.