Effect of Exhaust Cleanup Systems on Gas Turbine Combustor Selection
Diffusion flame combustors have served the gas turbine industry well since the invention of jet engines in the 1930’s. They provided fuel flexibility and the diffusion flame process gave the designer many options. Recently for heavy-duty land gas turbines, the need to reduce NOx emissions has led to the introduction of premixed combustor designs (Dry Low NOx - DLN) that have reduced fuel flexibility, operating range and reliability. With the increasing use and availability of Exhaust Cleanup Systems (EXCLUS) such as SCR and CO reduction catalysts, new gas turbine plant schemes that use diffusion flame combustors are back in the picture. This paper proposes a number of technique combinations that could achieve low NOx targets using diffusion flame combustors.