Method of neutralization of nitrogen oxides in area of low-temperature plasma

Abstract

In the production of 1 ton of oxalic acid, 2000 m3 of gases with an average content of 2–2.5% of nitrogen oxides are emitted into the atmosphere. The existing methods of air purification from nitrous gases have a number of disadvantages and therefore cannot be widely used in industry. Based on theoretical and experimental studies, a new method for the thermal decomposition of nitrogen oxides has been developed, which provides for the sanitary purification of waste gases in the production of oxalic acid, up to the maximum permissible concentrations. The process of thermal decomposition of nitrogen oxides in the temperature range from 500 to approximately 50000С has been studied. To achieve such temperatures, an arc plasma torch with a tungsten cathode and a copper anode was used. The degree of decomposition was determined by measuring the NO concentration at the inlet and outlet by the evacuated flask method. The effects of gaseous (hydrogen, ammonia, methane, natural gas), liquid (kerosene, gasoline, fuel oil), and solid reducing agents (coke, coal, graphite) on the decomposition reaction of nitrogen oxides were also studied.