Environmental and thermodynamic evaluation of CO2 capture, transport and storage with and without enhanced resource recovery

This study evaluates the environmental and thermodynamic performance of six coal-fired power plants with CO2 capture and storage. The technologies examined are post-combustion capture using monoethanolamine, membrane separation, cryogenic fractionation and pressure swing adsorption, pre-combustion capture through coal gasification, and capture performing conventional oxy-fuel combustion. The incorporation of CO2 capture is evaluated both on its own and in combination with CO2 transport and geological storage, with and without beneficial use.Overall, we find that pre-combustion CO2 capture and post-combustion through membrane separation present relatively low life-cycle environmental impacts and high exergetic efficiencies. When accounting for transport and storage, the environmental impacts increase and the efficiencies decrease. However, a better environmental performance can be achieved for CO2 capture, transport and storage when incorporating beneficial use through enhanced oil recovery. The performance with enhanced coal-bed methane recovery, on the other hand, depends on the impact categories evaluated. The incorporation of methane recovery results in a better thermodynamic performance, when compared to the incorporation of oil recovery. The cumulative energy demand shows that the integration of enhanced resource recovery strategies is necessary to attain favourable life-cycle energy balances.

► Evaluation of six different CO2 capture technologies for coal-fired power plants.
► Calculation of life-cycle environmental impacts and exergetic efficiencies.
► Suitability of post-combustion capture with membrane separation.
► Suitability of pre-combustion capture through coal gasification.
► Improved performance when incorporating enhanced resource recovery.