Utilisation of Evaporated Ethanol in Natural Gas Fired Lean-Premix Combustors of Power Generation Gas Turbines

With the transition to low-carbon power generation there will be a continuing need for dispatchable power. This could be provided by gas turbines fired with low-carbon fuels. It has been shown that micro-gas turbines with lean premix natural gas combustors can successfully fire a wide range of evaporated liquid fuels without modification. It is possible that larger power generation gas turbines will also be able to utilise evaporated liquid fuels without significant modification. Ethanol and methanol were considered by the authors, but methanol was eliminated during pre-screening. This preliminary assessment considers the potential for power generation gas turbines to burn evaporated ethanol in lean premix burners. A Siemens SGT5-2000E gas turbine as operated in Uniper’s Killingholme plant is used as an example. Impacts on key combustion performance parameters (emissions, combustion dynamics, flashback and blow-off) have been considered. These parameters are affected by both chemical properties of the fuels and the effect of their physical properties on burner aerodynamics, fuel placement and mixing quality. The evaluation included a combination of chemical kinetic modelling and isothermal CFD. This analysis has concluded that the concept would be viable and warrants further investigation.