GAS-TURBINES ABOVE 150-MW FOR INTEGRATED COAL-GASIFICATION COMBINED CYCLES (IGCC)

Commercial IGCC power plants need gas turbines with high efficiency and high power output in order to reduce specific installation costs and fuel consumption. Therefore the well-proven 154 MW V94.2 and the new 211 MW V94.3 high-temperature gas turbines are well suited for this kind of application. A high degree of integration of the gas turbine, steam turbine, oxygen production, gasifier, and raw gas heat recovery improves the cycle efficiency. The air use for oxygen production is taken from the gas turbine compressor. The N2 fraction is recompressed and mixed with the cleaned gas prior to combustion. Both features require modifications of the gas turbine casing and the burners. Newly designed burners using the coal gas with its very low heating value and a mixture of natural gas and steam as a second fuel are developed for low NOx and CO emissions. These special design features are described and burner test results presented.