Enabling 10mol/kg Swing Capacity via Heat Integrated Sub-ambient Pressure Swing Adsorption
This project focused on the development of a post-combustion CO 2 capture technology for coal-fired power stations. The core concept of the technology was the combination of an adsorption-based separation with combustion flue gas cooling, compression followed by heat and power recovery. The key features of the adsorption unit (which captures and purifies the CO 2 ) are the use of high flow fiber-based adsorption systems that incorporate materials that manage the significant amounts of heat released during the adsorption separation. The adsorbent material utilized was a hybrid organic-inorganic material (a metal-organic framework) that had the proper combination of separation selectivity and CO 2 capture capacity. In this case, record-setting, process-relevant CO 2 capture capacities (approximately 8-10 mol of CO 2 per kg of adsorbent “swing capacities”) were observed in experimental measurements of the adsorptive separation. The experimental work was accompanied by detailed multi-level simulation works, which investigated the molecular mechanism for the high CO 2 capture efficiencies, the heat and mass transport dynamics within the separation system, and the process-level integration of the various systems associated with the technology. Overall, the analysis conducted in this work indicates that this technology can potentially reach CO 2 capture costs as low as 40-50 dollars/tonne with capital costs of 250M-400M dollars for the 550 MW e basecase established by the National Energy Technology Laboratory.