Thermoeconomic Evaluation of CO2 Compression Strategies for Post-Combustion CO2 Capture Applications

Abstract

CO2 compression significantly contributes to the overall efficiency penalty and capital cost increase resulting from CO2 capture. Performance improvement measures for this process step hence have the potential of considerably improving the overall economic picture for CO2-lean power generation from fossil fuels. The present paper gives an insight into the thermodynamics of CO2 compression in a natural gas combined cycle power plant with post-combustion CO2 capture. The work aims at gaining a better understanding of the boundary conditions, thermodynamic limitations, and performance entitlement governing the CO2 compression process. With the help of process simulation, different technically feasible strategies for compressing CO2 are evaluated, quantified, and compared against their thermodynamic entitlement; the compression power reduction and the maximum cost allowable for the performance improvement measures suggested are estimated.