Process intensification for carbon capture could reduce costs

In conventional solvent-based carbon-capture systems, CO2-rich exhaust gas contacts gravity-driven solvents in a vertical packed-bed column. A novel approach developed by Carbon Clean Solutions USA Inc. (CCSUS; Cumming, Ga.; www.carboncleansolutions.com) employs centrifugal force from rotating horizontal packed beds to effect the gas-to-liquid contact. The higher g-forces allowed by the rotation improve mass transfer and enable smaller units to be used. Smaller units would lower capital costs compared to traditional carbon capture. The system has the potential to reduce the levelized CO2 -capture cost to the U.S. Dept. of Energy (DOE) target of $30/ton or less. Under a $2.9-million cooperative agreement from the DOE’s National Energy Technology Laboratory, GTI (Des Plaines, Ill.; www.gti.energy) is the prime contractor leading the effort with CCSUS to scale up this process-intensification approach from laboratory scale size to a larger, integrated carbon-capture system capable of removing 1 ton/d CO2 from power-plant fluegas. The novel carbon-capture approach, known as ROTA-CAP technology, is designed such that CCS’s intensified solvents are pumped into the center of the rotating cylinder, and the centrifugal force from the rotation…