Studies On Treatment Of Nitrogen Oxides Gases In Industry By Wet Process

In chemical industry, NOX gases are largely let off from nitric acid plants, oxalic acid plants, nitro amine plants, dynamite plants and other plants which manufacture or use nitric acid, which not only waste useful resource, but also bring serious hazard for the human being and ecosystem.So, This paper introduced several methods in the reduction of NOx for commercial use and in research stage,including selective catalytic reduction and selective non-catalytic reduction,aqueous alkaline absorption,adsorption treatment and biological treatment.The current application and prospective of these methods were reviewed,and these characteristics and existing problems were analyzed . The research progress and trend in the reduction of NOx were discussed.considering social and economical benefit of the plants, studies on the treatment of nitrogen oxides by wet process at normal pressure appears to be an increasingly important theoretical and practical significance for the prevention of environmental pollutants.The paper deeply study kinetics of reaction and mechanism of mass transfer in the process of Nitrogen oxides absorption in nitric dilute acid. it deeply discuss and analyse the controlling condition and the influencing factor in the process of Nitrogen oxides absorption from the aspect of oxidization of NO and absorption of NO2.Nitrogen oxides from the process of oxalic acid production can form nitric acid by being dissolved into water; reclaimed nitric acid can be used again by production shop, so nitrogen oxides absorpted by water is the treatment technology which belongs to clean chemistry. Therefore, through the analysis of the absorption process, the technological process for nitrogen oxides changing from exhaust gases into nitric acid was established. The fact showed that absorption results were wonderful. The model provides practical basis for absorption process design.