Reaction Chemiluminescence and its Relationship to Emissions and Stability in a Model Industrial Burner

In order to meet the increasingly stringent emissions targets for stationary power production, combustion applications are moving toward a lean premixed strategy with the potential for high levels of flue gas recirculation. Although effective at reducing NOx emissions, this type of operation suffers from potential increases in CO emissions and decreases in stability. In order to operate safely and with the highest performance, a sensor capable of gauging stability is desired. Unlike the current industrial flame scanners which serve an "on-off' function, the desired stability sensor would quickly alert the operator of the onset of instability, thereby widening the operability envelope by encompassing regimes formerly believed "unstable." To be successful, this sensor must be robust, inexpensive, and semi-quantitative. This paper describes the investigation of flame radical chemiluminescence as a potential feedback sensor. The flame chemiluminescence measured were for OH, CH, and CO2.