低能耗非热等离子体NO还原特性

NO Reduction Characteristics with Low Energy-Consumption Using Non-Thermal Plasma

分别建立了新型低能耗 N2 -NO系统的单电极尖端放电和介质阻挡放电非热等离子体 NO还原实验系统 ,通过实验研究了电极极间电压 V和尖端距离 lg 以及 Al2 O3,Ca O,Mg O,玻璃等不同介质阻挡对活性 N原子产生及 NO还原率的影响规律。结果表明 ,NO还原率随尖端距离 lg 的增大而先增后减 ,随极间电压 Vm 和气体停留时间 t的增大而增大 ,尖端距离 lg 是决定电极之间的电场强度 Eg 和气流停留时间 t的关键几何变量。利用活性N原子的产生条件解释了放电外轮廓直径及电场强度随尖端距离 lg 变化的消长规律。不同阻挡介质所形成的气体放电的电场强度不同 ,提供给活性粒子的能量也不同 ,从而对 NO还原效果具有不同的影响。单电极尖端放电 NO还原特性的研究结果对介质阻挡放电 NO还原有指导作用。

Using an experimental NO reduction s ystem with single-electrode tip discharge structure and dielectric barrier disc harge structure respectively, NO reduction characteristics of the N 2-NO syste m and the effects of dielectric characteristics on NO reduction are revealed to guide the engineering practice. Experimental results show that the amount of act ive N atom and NO reduction rate increase at the beginning of the increasing dis tance between two tips and then drop when the distance exceeds to a certain va- lue. The NO reduction rate increases while the voltage between two electrodes or the resident time of gas flow increases. The distance is a key geometrical vari able which can determine the electric field intensity between two electrodes and gas flow resident time. Experimental results of NO reduction rate with differen t dielectrics, such as Al 2O 3, CaO, MgO and glass show that the electric fiel d intensity is different with different dielectrics, because it brings different energies to the active particles in discharge room, thus causing different NO r emoval rates.