High-Efficiency Capture and Utilization of CO2 from Flue Gas Using Algae-Based Amino Acid Salt Solution

The power industry in the U.S. emits more than 1.8 gigaton of CO2 (30% of the total CO2 emissions) per year. New solutions are urgently needed to capture and utilize the CO2. It has been reported that amino acids neutralized with a base compound as alternatives of alkanolamines to capture carbon dioxide (CO2) from flue gas. The study develops a new integrated system based on algal amino acids. The system applies four consecutive steps of preparation of algal amino acid salt solution, algal amino acid salt absorption, spent amino acid utilization of polyurethane production, and conversion of collected CO2 for organic acid production to realize CO2 capture and utilization. A bench-scale system was used to evaluate performance of CO2 capture and utilization. A detailed techno-economic analysis and life-cycle assessment are conducted based on the results from the bench-scale studies. A technically feasible and economically sound CO2 capture and utilization process is concluded from this study.