Dielectric Barrier Discharge Removal Of No

The coaxial cylinder-tube dielectric barrier discharge(DBD) reactors were designed tostudy the influences of gas composition and the structure parameters of reactor on NOconvertion in a plasma.The different reacting systems included N₂/NO,N₂/NO/O₂,N₂/NO/H₂O(g) andN₂/NO/O₂/H₂O(g). The experimental results showed that the NO removal efficiencyincreased with the enhancement of the power supply in all the systems. The decompositionof NO decreased with inlet gas concentration increasing, while oxydation of NO reachedmaximum before decreasing. In the N₂/NO system, NO decomposition to N₂ and O₂ is inthe majority. The main effect of the gas-phase reactions in a plasma is the oxidation of NOto NO₂ in N₂/NO/O₂ system and N₂/NO/H₂O(g) system. In N₂/NO,N₂/NO/O₂ andN₂/NO/H₂O(g) systems, the NO₂ production efficiency reached the maximum whenapplied voltage was 9kV, were 23%,37% and 26% respectively. In the N₂/NO/O₂/H₂O(g)system, the NO₂ production efficiency increased with applied voltage elevating, and it was37% when applied voltage was 15kV.The structure parameters of reactor included the number of dielectric-slab,dielectric-slab material,central electrode structure and material,discharge gap and thenumber of reactor. The experimental results indicated that NO removal efficiency and theNO₂ production efficiency in the singer-dielectric-slab reactor were higher than thedouble-dielectric-slabs, but NO removal efficiency was better in the double-dielectric-slabswhen the applied voltage was higher. The NO removal efficiency increased with increasingdielectric constant of the dielectric material Compared with 3.5mm-gap-reactor, the NOremoval efficiency of the 1.5mm-gap-reactor was better, but the 1.5mm-gap-reactor wasdisadvantageous to the NO₂ production. The changes of central electrode structure havemarkedly influenced on the NO removal. NO removal efficiency and the NO₂ productionefficiency all must be better when the air flow via two plasma reacrors. Industrial usedDBD reactor which will process load of 1000Nm³·h^-1 was preliminary designed.