Simultaneous catalytic reduction of N2O and NOx produced in a fluidized bed incineration of sewage sludge

Abstract

AbstractFluidized bed incineration of sewage sludge could produce large amounts of N2O due to the relatively high nitrogen content of the sewage sludge and low incineration temperatures. In this study, N2O and NOx emissions released during the fluidized bed incineration of dried sewage sludge powder were investigated. Sewage sludge feeding rate was about 8∼10 kg/h, and bed aspect ratio was fixed to ca. 1.2. Superficial velocity was adjusted to ca. 1.9 m/s. The concentrations of N2O and NOx in the exhaust gas were greatly influenced by bed temperature in a range between 850 °C and 950 °C. In the simultaneous catalytic reduction of N2O and NOx on an Fe/BEA pellet catalyst with NH3, most of the N2O and NOx were removed when heated above the inlet reaction temperature 410 °C. Thus, simultaneous catalytic reduction was shown to be a promising N2O abatement technology for the fluidized bed incineration of sewage sludge. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd