Study On Removing NO_x From Flue Gas By Adding Ammonia And Propylene In Pulsed Discharge

The denitrification process using pulsed discharge plasma technology has been focused on by many researchers recently because of its advantages over traditional treatment methods for flue gas and a lot of development has been achieved. However, there are still some problems to be solved such as the low NO_X removal efficiency, which results in the low energy efficiency of denitrification before this technology is applied to industry. Ammonia and propylene were added to the reactor in the study. The reactor contains two electrodes, which are needle-plate pulsed discharge activation electrodes system and wire-plate pulsed discharge field system, to improve NO_X removal efficiency. Combined with the project 863 during the fifteenth program, the NO_X removal rate was investigated using pulsed discharge, activation field in the presence of ammonia or propylene, and two pulsed discharge field. At the same time, some influencing factors on NO_X removal rate including initial NO_X concentration, the dose of ammonia and propylene and gas flow and some mechanism of this method were discussed.The main experimental conclusions are summarized as follows:1. The needle-plate pulsed discharge activation field had good effect on the activation of ammonia and propylene. NO_X removal efficiency was better using both pulsed discharge field and activation discharge field in the presence of ammonia added from the needle electrodes than using either pulse discharge field or activation discharge field. In addition, NO_X removal efficiency was the best using pulsed discharge field and activation discharge field in the presence of both propylene and ammonia added from the needle electrodes. It can be concluded that the NO_X removal efficiency adding both propylene and ammonia is better than adding the sole ammonia.2. According to the experimental results and the analysis of mechanism, adding propylene is feasible for improving NO_X removal rate distinctly.3. NO_X removal rate decreased with the increase of flue gas and initial NO_X concentration and increased with the increase of the dose of propylene.4. The NO removal rate of 76% and NO_X removal rate of 54% were obtained in the case of energy density was 2Wh/Nm³, initial concentration of NO_X and NO were 81ppm and 80ppm, the flow rate was 157Nm³/h, the average temperature of the reactor was 70 °C, the molar ratio of NH₃ and NO was1: 1 and the molar ratio of C₃H₆ and NO was1: 1.