大気圧拡散状グロー放電を用いたNO処理特性

抄録

In present research, experiments using a diffuse glow discharge, which is one of non-thermal plasma, were carried out to remove NO_x. To generate diffuse glow discharge a double discharge method was used and it was consisted of two discharges, pre-discharge and main discharge. The pre-discharge produces many initial electrons around cathode and generates the main discharge easily at atmospheric pressure.
The experiments employed two kinds of sample gas, NO/N₂ mixture and NO/N₂/O₂ mixture gas, with several different NO concentrations for removing N_Ox, and adjusted at 1.25 [l/min] for all measurements. Using NO/N₂ mixture gas a reduction rate of NO decreased with increasing initial NO concentration. Thus the present NO_x reactor can remove efficiently at the region of low NO_x concentration. Nevertheless, an energy yield of NO removal improved and reached 8.82 [mg/Wh] at initial NO value of 186 [ppm] which is about 5 or 6 times comparing to conventional discharge methods. Steepness of main voltage was important factor for removing NO_x. With NO/N₂/O₂ mixture gas the reduction rate of NO reached 100 [%] at O₂ mixture rate of 20[%] because NO oxidation was accelerated drastically by generated ozone together with O atoms. The energy yield of NO removal was 21.9 [mg/Wh] which is about 2.5 times higher than one of NO/N₂ mixture gas.