2ND-GENERATION LOW-EMISSION COMBUSTORS FOR ABB GAS-TURBINES - FIELD-MEASUREMENTS WITH GT11N-EV

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-NO(x) < 2.5 ppmv (15 percent O2, natural gas), CO < 8 ppmv, UHC<5 ppmv-were reached. NO(x) values are even lower than 15 ppmv at base load. The NO(x) 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.