Extending the Concept of Parasitic Energy By Introducing Water Competition

A promising way to significantly reduce the CO₂ emission of power plants is Carbon Capture and Sequestration (CCS). Separating and compressing CO₂, however, impose a large additional energy load on power plants, which in turn is not available for electricity production. The concept of parasitic energy predicts and minimizes the additional energy load on a material-by-material basis and hence, is considered a potential means to evaluate materials for CCS. Besides CO₂ and N₂, water plays a crucial part in CCS, due to its high affinity to bind to the adsorption sites designated for CO₂, which poses a special challenge to the separation process. 

On the basis of Grand Canonical Monte Carlo (GCMC) simulations we calculate and implement water isotherms of all-silica zeolites to ensure a more realistic prediction of parasitic energy. Several flue gas compositions are analyzed, including direct air capture, to illustrate the difference in parasitic energy requirement induced by the change in CO₂ concentration.