Novel Exchanger Type Vacuum Temperature Swing Adsorption for Post-Combustion CO2 Capture: Process Design and Plant Demonstration

Carbon capture and storage (CCS) is a crucial technology for the mitigation of greenhouse gas emissions while sustaining the energy security during the transition from fossil fuel to renewables. However, one of the biggest challenges to commercialize CCS is to develop an effective and less energy intensive capture technology. In this study, we demonstrate a novel multi-columns-in-column exchanger type adsorption unit (ETAU) for post -combustion carbon capture from a side stream of a 4000 MW ultra-supercritical coal-fired power plant. Using vacuum temperature swing adsorption (VTSA) process and 13X-APG adsorbent, we achieved a CO2 product purity of 94.4 %, and a recovery of 90.6 % on a single column adsorption unit cycle from pre-dehydrated raw flue gas. Another 4-bed 10-step VTSA process was carried out achieving a CO2 product purity and recovery of 93.5 % and 84.3 %, respectively, using the same raw flue gas. For this experimental unit in a much-limited scale, the greatest heat consumption is 3.71 GJ/tonCO2, and the electricity consumption is 128 kWh/tonCO2. Our eval-uation indicates that the heat energy consumption by VTSA employing an ETAU design is more economical than that solely using temperature swing process for producing comparable carbon capture purity and recovery. Advanced heat management strategies have been developed to lower the energy consumption of the capture process making the utilization of ultra-low-grade heat viable. Scale-up of this novel multi-columns-in-column exchanger type adsorption unit with water resistant pre-layer is expected to further reduce the energy penalty and accelerate the deployment of carbon capture.