非热等离子体强化碱液吸收脱除烟气中NO和Hg^0的研究  

Removal of NO and Hg^0 in Flue Gas Using Alkaline Absorption Enhanced by Non-thermal Plasma

作　　者：罗宏晶[1] 朱天乐[1] 王美艳[1] 

机构地区：[1]北京航空航天大学环境科学与工程系,北京100191

出　　处：《环境科学》2010年第6期1682-1687,共6页Environmental Science

基　　金：国家高技术研究发展计划(863)项目(2007AA06Z300);北京市科学基金项目(8072017)

摘　　要：采用正电晕放电产生非热等离子体将模拟烟气中的NO和Hg0氧化成更易吸收的NO2和Hg2+,从而强化其碱液吸收脱除,并考察放电电压及入口SO2和NO浓度对氧化和脱除效果的影响.结果表明,随着电压升高,NO和Hg0的氧化和脱除量增加.当NO浓度为134mg/m3,放电电压为12.8kV时,吸收塔出口NO和NO2浓度分别为0和69mg/m3.当Hg0浓度为110μg/m3,放电电压为13.1kV时,吸收塔出口Hg0和Hg2+浓度分别为22μg/m3和11μg/m3.SO2对Hg0的氧化和脱除具有一定促进效应,且这种效应随SO2浓度提高而增强,但SO2对NO的氧化和脱除影响不大.NO对Hg0氧化有明显的抑制效应,随着NO浓度提高,Hg0氧化和脱除量显著降低.当800mg/m3SO2、134mg/m3NO和110μg/m3Hg0共存时,对应77J/L的能量输入,NO和Hg0的脱除率分别为57%和31%.Non-thermal plasma（NTP） induced by positive corona discharge was utilized to oxidize NO and Hg0 to more water-soluble NO2 and Hg2 ＋ under the conditions of simulated flue gas.The effects of discharge voltage and inlet SO2 and NO concentrations on NO and Hg0 oxidation and their removals by alkaline absorption were investigated.The results show that the oxidation and removal of NO and Hg0 are enhanced with the increase of discharge voltage.The concentrations of NO and NO2 at the outlet of absorption tower are 0 and 69 mg /m3 with an inlet NO concentration of 134 mg /m3 and a discharge voltage of 12.8 kV while the outlet concentrations of Hg0 and Hg2 ＋ are 22 μg /m3 and 11 μg /m3 with an inlet Hg0 concentration of 110 μg /m3 and a discharge voltage of 13.1 kV.The presence of SO2 slightly improves the oxidation and removal of Hg0 while it has almost no effect on NO oxidation and its removal.The oxidation and removal of Hg0 are significantly inhibited with the increase of inlet NO concentration.In the coexistence of 800 mg /m3 SO2,134 mg /m3 NO and 110 μg /m3 Hg0,the removal efficiencies are 57% for NO and 31% for Hg0 with an energy input of 77 J /L.

关 键 词：非热等离子体 碱液吸收 NO Hg0 SO2 脱除 烟气 

分 类 号：X511[环境科学与工程—环境工程]