Development of Gaseous Pollutants Removal Processes by Using Atmospheric Pressure Non-Thermal Plasma

作为3年项目的最后一年，取得了以下新成果。对于来自废热烟气的处理，其中反应器填充有沸石（Na-ZSM 5）颗粒的非热等离子体的脱NOx性能在没有放电的情况下大于60%，并且NOx的去除率在等离子体放电的情况下变为大约100%。但沸石的吸收作用占主导地位，单纯的综合作用尚不清楚。对于空气中的1，000 ppm三氯乙烯（TCE），也进行了VOCs分解试验。螺栓式反应器是最佳的，均匀的等离子体产生是提高能量效率的关键因素。就等离子体激发高压的频率依赖性而言，与更高频率驱动相比，60 Hz的等离子体激发高压的频率依赖性最好。但对于臭氧生成，500 Hz驱动在某些时候比50 Hz更有效。钒氧化物是提高三氯乙烯分解能量效率的有效物质。用可调谐准分子激光器（KrF）观察了OH自由基等的激光诱导荧光（LIF）。首次在世界上观测到二维时间分辨的OH自由基分布。OH自由基信号的峰值出现在比脉冲信号晚30微秒处，说明低温等离子体处理空气净化技术是非常有效的，有待于进一步的发展。

As a final year of 3-years project, following new results are obtained. For flue gas processing from cumbustion, DeNOx performance of the non-thermal plasma where a reactor was filled with zeorite (Na-ZSM5) particulates is more than 60% without discharge and removal rate of NOx becomes roughly 100 % with plasma discharge. However, absorption effect of zeorite was dominats and pure combined effects was not yet clear. For 1,000 ppm trichloroethylene (TCE) in air was also processed as VOCs decomposition tests. A bolt type reactor was the best and uniform plasma generation was fould to the essential factor to improve energy efficiency. Concerning to the frequency dependence of the plasma exciting high voltage, commercila 60 Hz was the best compared with higher frequency drive. But for ozone generation, 500 Hz drive was more efficient than 50 Hz at some times. Vanajium oxide was found to the effective materials to improve energy efficienecy for TCE decomposition. A tunable excimer laser (KrF) was applied to observe laser-induced fluorescence (LIF) from OH radical and others. Two dimentional and time-resolved OH radical distributions were observed for the first time in the world. OH radical signal shows its peak at 30 microseconds lalter than pulse.It was concluded that Non-Thermal Plasma Processing for Air Cleaning is very effective and futher development will be done for practical usage.