NOx and SOx emissions of a high sulfur self-retention coal during air-staged combustion

Abstract NO x and SO x emissions of air-staged combustion were investigated in a 1 MW tangentially-fired furnace combusting a high sulfur self-retention coal. Two variables including the air stoichiometric ratio of primary combustion zone and the relative location of over-fire air (OFA) injection ports were studied. These results suggest that NO x reduction efficiency monotonically increases with increasing the relative location of OFA injection ports, and the lowest NO x emissions are achieved when the air stoichiometric ratio of primary combustion zone is 0.85. In the meantime, SO x emissions can be effectively reduced when the air stoichiometric ratio of primary combustion zone is 0.85 or 0.95, and SO x emissions monotonically decrease with increasing the relative location of OFA injection ports.

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