低温等离子体注入定向Hg氧化实验研究

Experimental Study on Forced Hg Oxidation by Non-thermal Plasma Injection

燃煤烟气汞脱除的核心是单质汞(Hg^0)的高效氧化。本文基于低温等离子体技术,系统研究了放电电压、自由基源气体组成、烟气温度及烟气组分对氯自由基(Cl)注入强化氧化Hg^0的影响,结果发现降低注入点烟气温度、增加Cl注入量以及烟气中的NO均有利于Hg^0氧化,最佳放电电压的选取则与自由基源气体组成密切相关,一定条件下,注入极少量C_(12)(19 mg/m^3)即可获得97.9%的Hg^0氧化率。

High efficiency elemental mercury （Hg^0） oxidation determines mercury removal in coal combustion flue gas. Based on non-thermal plasma （NTP） technology, this paper experimentally investigate the influences of dielectric barrier discharge （DBD） voltage, composition of free radical source gas, flue gas temperature and composition on the forced Hg^0 oxidation by Cl radicals injection. Results showed that lower flue gas temperature, more Cl radicals injection and the existence of NO in flue gas increased Hg^0 oxidation. The optimal discharge voltage was determined by the composition of free radical source gas. Under certain conditions, a Hg^0 oxidation rate as high as 97.9% can be obtained by as low as 19 mg/m^3 of C12 injection.