In the highest firing-temperature machines used for power generation, such as the recent FB-class and G-class machines, gasphase
combustion temperatures may need to exceed 1525°C (2780°F), before addition of necessary cooling air, in order to meet turbine
rotor inlet temperature requirements. At the current level of machine, combustor, and catalyst materials development, this means that
NOx
emissions will likely exceed 3 ppm at 15% O2
. In spite of this, there are possible developments to reduce NOx
emissions at these
high flame temperatures, and there are non-emissions-related benefits of catalytic combustion (improved turndown and combustion dynamics) that are available immediately