Treatment on Low NOx Concentration and DEP Collection with Barrier Discharge System Superposing TiO₂

Abstract

The automobiles exhaust carbon particles and NOx into the air, and then gases accumulate in expressway tunnels. DC corona discharge is used widely in electrostatic precipitator (ESP). However, the ESP with DC corona discharge can little remove NOx. Therefore, we proposed a new barrier discharge type precharger to replace corona discharge type prechargers to remove NOx. When discharge is generated in the air, NOx necessarily is generated. Then, we need to grasp the lower limit NOx concentration to remove NOx from the gas. We focus attention on photocatalyst because it is effective in NOx removal. However, photocatalyst needs ultraviolet ray. Therefore, TiO₂ is painted on barrier discharge electrodes, an ultraviolet ray included in discharge luminescence was irradiated to TiO₂. Furthermore, the relationship between initial NOx concentration and removal characteristic is investigated in detail.