Executive Summary : | The transition from fossil fuels to zero/low carbon energy sources is crucial for nations aiming to achieve net-zero emission targets. Fossil fuels, such as oil, coal, and natural gas, contribute to over 60% of the world's energy demands, with transport and industry sectors being major consumers. While electrification of transport is a potential solution using renewable energy sources and batteries as energy carriers, limitations such as low energy density, high costs, and end-of-life battery management pose major challenges in its adoption at larger scales. Hydrogen (H2) and high-H2 capacity carriers like methane (CH4) and ammonia (NH3) have a gravimetric energy density of 20-120 times higher than current Li-ion batteries. Processes like steam methane reforming and ammonia cracking enable H2 production from CH4 and NH3, making them attractive energy carriers. Adoption in ICEs or gas turbines requires understanding their combustion and emission characteristics. Studies on NH3 combustion show slow reactivity, narrow flammability limits, and high NOx emissions. Blending NH3 with H2 or CH4 can improve reactivity but also introduce significant N2 dilution in fuel mixtures, potentially affecting blow-off limits and NOx emissions. Current technologies for H2 separation from the N2/H2 reformate gas are not cost-effective at large-scale applications, and retrofitting existing combustors with after-treatment devices increases overall costs.
The proposed project aims to understand the combustion characteristics of NH3-cracked fuels in a swirl-type combustor, develop a swirl gas-turbine combustor with optical access, and measure NOx emissions as a function of φ using an Exhaust Gas Analyser. Successful realization would provide insights into flammability regimes and NOx emission mechanisms of NH3-derived fuels, serving as a benchmark for developing efficient combustor operations. |