Production and Removal Mechanisms of Discharge NOxTreatment in N2/O2Gas Mixture

We investigated removal reactions of NO x in flue gas using streamer discharge, both experimentally and analytically. We clarified the reaction mechanism that can satisfy the experimental results in the N 2 /O 2 /NO x gas mixture. In a gas mixture including N 2 , NO, and 5% O 2 , the NO x removal amount decreases markedly, and NO x molecules are produced with a low initial NO concentration. Based on simulation focused on the streamer head, we evaluated dominant factors in the NO x removal reactions. The primary factor affecting the marked decrease in NO x removal is the effect of excited N radicals which react rapidly with O 2 to produce NO. Another factor that causes the NO x production is the reaction of N+NO 2 , in which NO 2 molecules are produced by O 3 . Based on the reaction mechanism, we estimated the reduced electric field E / n and the N radical production that fit the experimental results.