Second-Generation Low-Emission Combustors for ABB Gas Turbines: Field Measurements With GT11N-EV

Abstract

In February 1991, a type GT11N gas turbine (Midland, USA) was retrofitted with ABB’s new EV-Silo-Combustor. Tests were then carried out to examine the operation concept, to demonstrate the technical reliability, and to confirm the low emission performance of this new technology. This paper will describe: the combustor design—one single silo combustor mounted on the turbine and equipped with 37 Ev burners; and the results of the extensive field measurements—the operation concept (lean premix combustion without any pilot diffusion flames, 7 burner groups) is simple and reliable. The emission targets—NOx <25 ppmv (15 percent O2 , natural gas), CO<8 ppmv, UHC<5 ppmv—were reached. NOx values are even lower than 15 ppmv at base load. The NOx predictions for the GT11N-EV, based on the results of high-pressure tests in Cologne (ASME Paper No. 90-GT-308), compared very well with the results of field measurements.