Energetic analysis of a syngas-fueled chemical-looping combustion combined cycle with integration of carbon dioxide sequestration

Abstract

Chemical-looping combustion for power generation has significant advantages over conventional combustion. Mainly, it allows an integration of CO2 capture in the power plant without energy penalty; secondly, a less exergy destruction in the combustion chemical transformation is achieved, leading to a greater overall thermal efficiency. Most efforts have been devoted to systems based on methane as a fuel, although other systems for alternative fuels have can be proposed. This paper focus on the study of the energetic performance of this concept of combustion in a gas turbine combined cycle when synthesis gas is used as fuel. After optimization of some thermodynamic parameters of the cycle, the power plant performance is evaluated under diverse working conditions and compared to a conventional gas turbine system. Energy savings related with CO2 capture and storage have been quantified. The overall efficiency increase is found to be significant, reaching values of around 5% (even more in some cases). In order to analyze the influence of syngas composition on the results, different H2-content fuels are considered. In a context of real urgency to reduce green house gas emissions, this work is intended to contribute to the conceptual development of highly efficient alternative power generation systems.