Energy & Fuels, Vol.31, No.9, 9760-9775, 2017
Evaluating the Feasibility of a TSA Process Based on Steam Stripping in Combination with Structured Carbon Adsorbents To Capture CO2 from a Coal Power Plant
The present work evaluates the feasibility to capture at least 85% of the CO2 emitted by an advanced supercritical pulverized coal power plant of 800 MWe, delivering a CO2 product with a purity of 95% (dry basis) or higher, using an adsorption-based postcombustion capture process based on carbon honeycomb monoliths regenerated by steam stripping. Process performance has been evaluated through the dynamic simulation of the cyclic adsorption process. The fixed bed adsorption model, which was validated against experimental results, is based on the mass, momentum, and energy conservation equations, and it accounts for competitive adsorption between the three main flue gas components: N-2, CO2, and H2O. The evaluated TSA process meets the targets for the capture rate and product purity, with a heat duty of 3.59 MJ kg(-1) CO2, which is close to the specific reboiler duty of the benchmark amine-based absorption process. Materials and process development will lead to lower duties. A sensitivity analysis was carried out, and it has shown that slightly faster adsorption kinetics for CO2 could drop the specific heat duty of the process to 2.89 MJ kg(-1) CO2, which is lower than that of the benchmark technology. From the process point of view, the use of waste heat from the power plant could further reduce the energy penalty of the integrated CO2 capture process.