Sustainability of natural gas chemical looping combustion from efficiency, economic and emergy analyses

Post-combustion (PC) was the mature technology for CO2 capture from a power plant, but the sorbent regeneration diminished its efficiency. The chemical looping combustion (CLC) was proposed to serve power plants with higher efficiency. The objectives of this study consisted of (1) examine the sustainability of power production between PC and CLC and (2) investigate the high sustainability operation conditions. There are 6 case studies which were simulated using the Aspen plus program with the Peng-Robinson-Boston-Mathias model. All cases were evaluated by three quantitative aspects of thermal efficiency, economic, and emergy analyses. The best case from each analysis was different. Since emergy analysis expressed a holistic aspect, including resource usage, economic performance, and environmental burden, this indicator would be used for selecting the proper technology. In this study, the decision had made into two aspects. From a global viewpoint, the CLC with high energy recovery and HAT cycle would be selected since it had the lowest UEV, reflecting the least natural resource consumption. On the other hand, from a local viewpoint, the CLC without HAT would be selected since it had the highest ESI, which implied its sustainability since the process was less reliant on external resources.