Exergy Analysis of Commercial Carbon Dioxide Production from Flue Gases in a Trigeneration Power Plant

Abstract

The efficiency of a system with separate subsystems is compared with that of an integrated system developed by means of an informational approach to system organization. The comparison is based on exergy analysis. As an example, we consider a system for commercial carbon dioxide production from flue gases at a trigeneration power plant. The trigeneration power plant combines two subsystems: a Rankine cycle for flue gas heat recovery (after the removal of sulfur and nitrogen oxides); and a refrigeration cycle with an expander for the capture and extraction of carbon dioxide as a commercial product. The exergy efficiency of the integrated system is more than twice that of the system with the components operating independently of each other. This indicates a synergetic effect, in which the overall efficiency of the system exceeds the efficiency of either subsystem.