AZEP Gas Turbine Combined Cycle Power Plants - Thermo-economic Analysis

Abstract

Conventional power plants based on fossil fuel without CO2 capture produced flue gas streams with concentrations of CO2 between 3% and 15%, contributing to the threat of increasing global warming. Existing capture technologies such as post-combustion flue gas treatments using chemical absorption, pre-combustion carbon removal or combustion in O2/CO2 atmospheres suffer from significant efficiency penalties as well as major increases in investment costs. A less energy intensive concept for oxygen production is a mixed conducting membrane (MCM) reactor which produces pure oxygen from compressed air. The MCM reactor is best integrated into a conventional gas turbine combined cycle, called advanced zero emissions plant (AZEP), to provide an efficient and cost-effective power plant altogether. In this paper the economic performance of four different combined cycle alternatives in two different gas turbine sizes are evaluated; two of the combined cycles being based on the AZEP concept. The results show that the AZEP concept presents a more competitive system in terms of efficiency and economy compared to traditional capture systems.