A Flamesheet™ Combustion System With Cracked Ammonia as a Fuel

Abstract Hydrogen-fired combustion turbines will play a critical role in the decarbonization of the Energy sector. Retrofittable technologies to reduce carbon emissions from existing gas turbine power plants are desirable to aid with the transition and enable cost-effective interim solutions. Due to the scarcity of Hydrogen in today's market, the low volumetric Energy density of gaseous Hydrogen, and the expensive Energy needed to produce and maintain liquid Hydrogen (LH2), liquid Ammonia (LNH3), a traded commodity, becomes an attractive fuel for storing and transporting vast quantities of Energy across great distances. While direct combustion of Ammonia is producing an unmanageable level of Nitrogen oxides (NOx) from its fuel-bound Nitrogen, equipment may be colocated at a gas turbine site to crack NH3 into Hydrogen and Nitrogen. Additional equipment to obtain a pure Hydrogen stream can be eliminated if the resulting Hydrogen/Nitrogen blend can be directly used. The needed volumetric flow is far greater than that of pure Hydrogen or Natural Gas (NG), which presents design challenges that will be discussed. A novel combustor was designed, and high-pressure rig testing results are summarized in this paper to showcase the fuel flexibility of the FlameSheet™ combustion system technology, and its ability to operate with any blend of Natural Gas and cracked Ammonia. Differences in flame stability, emissions, and combustion dynamics will be compared between Natural Gas and cracked Ammonia operation. Considerations are also given to various engine operating concepts.