Staged Catalytic Combustion Method for the Advanced Zero Emissions Gas Turbine Power Plant

Abstract

The AZEP (Advanced Zero Emissions Power Plant) project addresses the development of a novel “zero emissions,” gas turbine-based, power generation process to reduce CO2 emissions. Preliminary calculations indicate the attractiveness of this concept in comparison to conventional tail-end CO2 capture. Key to achieving the AZEP project targets is the development of a combustion system to burn natural gas with nearly stoichiometric amounts of oxygen and high levels of exhaust gas dilution. Within the first part of this study the fundamental combustion properties of AZEP gas mixtures are quantitatively determined. Significant inhibition results from the high level of exhaust gas dilution. In the second part a staged, rich–lean combustion concept, proposed to improve combustion stability, is investigated. It was shown that significant levels of hydrogen could be produced by a first stage, partial catalytic oxidation (PCO) of methane. Furthermore, it is shown that the addition of this produced hydrogen improves the stability of the downstream, second stage burnout zone. It was demonstrated that the produced syngas could act to reduce the blowout limit by ca. 100 K as compared to homogeneous gas phase combustion.