Denitrification Reactions in Cement Production

The denitrification material was injected into the preheater and then gradually fed into the precalciner and rotary kiln with cement raw meal. The reaction temperature was gradually increased to over 1000 °C. In order to imitate the denitrification reactions in the chemical laboratory, the NO decomposition reaction was carried out in a quartz fixed-bed reactor on a laboratory scale and heated with an electrically controlled heating oven, as shown in Figure 2 [14 (link)]. The decomposition reaction of NO was conducted in a quartz tube reactor filled with 2 mL of denitrification material. The thermocouple was positioned at the reactor’s core to measure the temperature of the test. The overall flow rate was 300 mL/min. The conditions for the reactant gases were as follows: 1000 ppm NO and helium (He) balanced gas. The materials and reactant gas were heated using a heating rate of 15 °C/min from ambient temperature to 1000 °C. The concentrations of nitric oxide (NO), nitrogen dioxide (NO₂), and nitrous oxide (N₂O) were continuously monitored using a TENSOR 27 Fourier-transform infrared (FT-IR) spectrometer (Bruker, Germany), and the NO decomposition rate was calculated according to the following equation: