A Contaminant Tolerant Solvent for Carbon Capture in Existing Coal-Fired Power Plants

In the context of post-combustion CO2 capture processes, solvents with fast CO2 absorption rates will require more energy for regeneration. This challenge is exacerbated when aqueous solvents are applied to the capture of post-combustion CO2 from a utility gas stream, which contains such unique characteristics as high volumetric flow rate, low CO2 vapor pressure, and the presence of gas contaminants. This Small Business Innovation Research project is developing a novel, contaminant-tolerant solvent/stripping chemical hybrid process for post-combustion CO2 capture from utility flue gases. The process uses a proprietary solvent technology to achieve the DOE goal of reducing CO2 emissions at existing coal-fired power plants by 90% or more, with no more than a 35% increase in cost of energy. In Phase I, the proposed solvent was investigated and compared with the benchmark solvent, 30% wt MEA. This comparison was conducted via laboratory testing and system simulation, with respect to reaction kinetics, mass transfer, stability, and energy consumption. Technical feasibility was proven by demonstrating advantageous results compared to the benchmark solvent. In Phase II, the solvent technology and process will be evaluated in a pilot test facility and further validated at the National Carbon Capture Center (NCCC). A detailed techno-economic analysis will be performed to demonstrate that the proposed solvent and process could potentially meet the DOE target for CO2 capture. When fully developed, the proposed solvent technology will improve the economics of the national greenhouse gas sequestration program, improve the overall plant efficiency of existing coal-fired power plants, and reduce the cost burden to the utility industry and to the public.