(244a) Advanced Carbon Capture System for Power Plants

TDA Research, Inc (TDA) is developing a high capacity CO₂ adsorbent and demonstrating its technical and economic viability for CO₂ capture from coal-fired power plants. TDA uses an advanced physical adsorbent to selectively remove CO₂ from the flue gas. The sorbent exhibits a much higher affinity for CO₂ than N₂, H₂O or O₂. The sorbent binds CO₂ more strongly than common adsorbents, providing the chemical potential needed to remove the CO₂. However, because CO₂ does not form a true covalent bond with the surface sites, the regeneration can be carried out with only a very small energy input (<10 kcal per mol of CO₂) compared to amines (14.2 kcal/mol CO₂). We demonstrated the sorbent’s efficacy through multiple cycles for removing CO₂ from coal derived flue gas and the sorbent demonstrated a stable capacity. The presence of acid gases such as SO₂ and NOx (80 and 200 ppmv, respectively) and water vapor up to 15% vol. had no adverse effect on the CO₂ capacity. The regeneration of the sorbent and the recovery of CO₂ and its pressurization can be achieved by several approaches, including temperature and vacuum swing. A detailed techno-economic analysis using Aspen Plus^TM software was conducted in collaboration with University of California Irvine to estimate the impact of the TDA’s CO₂ capture system on plant efficiency and cost of electricity. Our system analysis showed that TDA’s CO₂ capture process will reduce plant efficiency by only 19.4% (compared to 31.2% reduction for amine scrubbers) while providing 90% capture. We will present the latest results from the field testing of the unit under the DOE sponsored work at the AIChE meeting.