Ammonia/syngas MILD combustion by a novel burner.

Ammonia has received increasing attention as one of the most attractive energy carriers because of its carbon-free nature and the established reliable and economic infrastructure for its storage and distribution. However, the low burning velocity and nitrogen-containment of pure NH 3 can cause some challenges for its combustion control such as flame instability and large NO x emissions. To overcome these issues, strategies of co-burning NH 3 with highly reactive fuels such as CH 4 or H 2 have been developed and applied. Syngas, which can be produced from biomass pyrolysis, is a promising alternative fuel in the transition from carbon-based fuels to carbon-free fuels. Therefore, comparing to co-firing NH 3 with CH 4 , co-firing NH 3 with syngas is a better environmentally friendly option to improve the NH 3 combustion property. However, co-firing NH 3 with syngas faces severer combustion instability, NO x emissions and NH 3 leakage due to the low heating value of syngas. To the best of the authors' knowledge, the NH 3 /syngas combustion with low NO x emissions and zero NH 3 leakage has not been achieved in a lab-scale combustor. In the present study, NH 3 /syngas MILD combustion was carried out in a novel burner developed in our previous work. In the novel burner, the high-temperature and diluted air produced by the lean premixed syngas combustion is the key to accomplish the MILD combustion of NH 3. The impact of the temperature and O 2 mole fraction of the HTDA on the emissions of NO, NO 2 , N 2 O, NH 3 , and CO was experimentally investigated with varying equivalence ratios and NH 3 flow rates. The chemical reactor network was employed to analyze the experimental observation from the chemical kinetic aspect. [ABSTRACT FROM AUTHOR]