Introduction

The reduction of NOx and CO2 emissions is of great importance in practical combustors (such as gas-fired turbines) due to the stringent NOx emissions regulations and the forthcoming legislation on greenhouse gases such as CO2 Two hetero-/homogeneous combustion technologies (the “fuel-lean” catalytically stabilized combustion, and the “fuel-rich catalytic, fuel-lean homogeneous” combustion) have been pursued lately in gas turbines. In those approaches, partial fuel conversion is accomplished heterogeneously in burners with a suitably large surface-to-volume ratio, such as catalytically-coated honeycomb monoliths, and complete fuel conversion is attained in a post-catalyst homogeneous combustion zone. This process leads to substantial reduction of NOx emissions (typically < 3 ppm). Moreover, catalytic combustion technologies allow for stable combustion even under heavy dilution (e.g. use of large exhaust gas-recycle, EGR). Combustion with large EGR is of interest in power generation as it allows for a twofold increase in the CO2 content of the exhaust gas, thus facilitating the capture and further sequestration of CO2.

At PSI the catalytic combustion processes are investigated experimentally and numerically in channel flow configurations. Particular emphasis is given in the study of the heterogeneous/homogeneous chemical and thermal interactions which are responsible for the onset of gaseous ignition. In situ measurements (laser based) are carried out over the catalyst boundary layer at pressures and temperatures relevant to those encountered in practical systems.

Research topics:

• Lean Catalytic (CST)
• Rich Catalytic (CPO)

Small Scales (Microreactors)