Dynamics Simulation of Vapour Assisted Ammonia Pollution Removal By Pulse Discharge Method

摘要

Though ammonia (NH_3) is one of the most highly produced inorganic chemicals in the world, its pollution disadvantage on air and water have drawn much attention. In this article, the NH_3 removal is investigated through pulse discharge method. A zero dimensional molecular reaction model is established and solved. The vapour assisting effect on the NH_3 gas removal is discussed due to the extremely soluble character of NH_3. Simulation indicates that the vapour additive has affected the H_2 and N_2 generating process. For vapour with several thousand'th ratio mixed, the electron collision on H_2O has been ignored. The results show that lower concentration vapour improves the removal efficiency in a very small extent, but higher vapour deteriorates it, with the optimal mixing concentration ratio between H_2O and NH_3 as 0.75:1000. For vapour with several tenth ratio mixed, the electron collision process on H_2O molecules is considered. More H_2O additive has significantly improved the NH_3 removal efficiency by accelerating the H_2 and N_2 generation process. At the vapour ratio of 750‰, the removal efficiency is 64.28%, which is remarkably higher than that of 37.81% without vapour added. H_2O additive has saving of 70% energy consumption. The initial NH_3 concentration is another factor to influence the removal efficiency. The higher the initial NH_3 input, the less the H_2O is decomposed into OH and H by electron impact, and the removal efficiency is decreased consequently.