| Plasma-processing for NOx removal (DeNOx) with catalysts is a new technology for flue gases treatment. With many characteristics of low investment, small operation spot, low operation expenses and etc, this technology has become an internationally accepted and new flue gas denitration with the most potential market and prosperous prospect. In this paper, we use non-thermal plasma generating by high voltage nanosecond pulse to treat NOx with catalysts. We design and utilize two kinds of additive to discharge and treat NOx, one is CH4 , the other is NH3.Several main factors of this technology are demonstrated here,including pulse voltage , position of pulse electrode ,and the influence of additive and temperature.We analysed their characters and their influence on the DeNOx process,and based on which the reaction mechanism of the catalytic reduction of NOx with additive activated by the high voltage pulse discharge plasma has been explored preliminarily. The conclusions can be get from the experiments of the catalytic reduction of NOx with additive activated by the high voltage pulse discharge plasma : 1)The concentration of NOx is effected by reduced pulse voltage. Higher is discharge voltage , better is removal result of NOx. 2)By adjusting the parameter of pulse electrode,reduction rate of NOx can be controlled. 3)The catalytic reduction of NOx with CH4 activated by the high voltage pulse discharge plasma has been investigated ,the optimum reaction temperature and pulse voltage ,are 440℃,more 10kv respectively .The experimental results show that in the optimum reaction condition,60% removal can be obtained. 4)The catalytic reduction of NOx with NH3 activated by the high voltage pulse discharge plasma has been investigated ,the optimum reaction temperature,pulse voltage ,O2 and n(NH3)/n(CH4) are 310℃, more 10kv ,round about 10% ,1.1 respectively .The experimental results show that in the optimum reaction condition,90% removal can be obtained. 5)It is found that the catalytic reduction of NOx with additive activated by the high voltage pulse discharge plasma is achieved mainly through a series of fast elementary reactions and that the active atom of CHx· and NHx· is the base for NOx removal. |
