Abstract
A technique for removing the NOx contained in combustion exhaust gas has been developed by using radicals produced in the arc plasma. The gas mixture of plasma operating gas Ar or N_2 and reducing agents such as H_2, diesel fuel and NH_3 are feeding into arc plasma torch. Radicals such as NH_2, NH, HC, N, H produced in plasma jet are mixed with the simulated exhaust gas (N_2+O_2+NO) in the reactor. The NO decreases as a result of the formation of the innocuous products N_2 and O_2 when O_2 is not contained in the exhaust gas, while the NOx increases with increasing input power to plasma in an oxygen-rich gas. The effects of plasma operating gas, input voltage and power to plasma, reduction agency, mixing position of radicals with exhaust gas, and O_2% contained in exhaust gas on the NOx removal rate are investigated experimentally. Also discussed are the usability of the hydrogen and the diesel fuel as reducing agent, as well as availability for a selective reduction process of NOx by ammonia.
