低温等离子体促进烟气中单质汞氧化的特性分析  

Enhanced Oxidation of Elemental Mercury in Simulated Flue gas by Non-Thermal Plasma

作　　者：林文锋[1] 张斌[1] 侯文慧[1] 周强[1] 杨宏旻[1] 

机构地区：[1]南京师范大学动力工程学院,江苏省南京市210042

出　　处：《中国电机工程学报》2010年第2期72-76,共5页Proceedings of the CSEE

基　　金：国家重点基础研究发展规划项目(973计划)(2006cb200302);国家自然科学基金项目(50976049);江苏省自然科学基金项目(BK2007224);教育部留学回国人员科研启动基金项目~~

摘　　要：建立了实验室规模的低温等离子体氧化单质汞效能测定系统。实验研究了在介质阻挡放电所产生的低温等离子体条件下,烟气中主要成分对单质汞氧化的影响规律。实验结果表明:低温等离子体对烟气中单质汞均可达到较高的氧化效率;O2和H2O单组分可显著促进单质汞的氧化,1.5%的O2和4%的H2O分别可以获得97.4%和92.5%以上的单质汞氧化效率,电离产生的O、O3、OH等具有氧化性的活性粒子起到了重要作用;CO2的存在会增加烟气的还原性氛围,对单质汞的氧化具有不利影响;在Hg/N2/O2/CO2/H2O复杂烟气氛围下,由于活性基团相互之间的制约,单质汞的氧化率平均为75%,在烟气中添加少量的HCl会明显提高单质汞的氧化率。提出了在等离子体条件下HCl离解并氧化单质汞的机制。A laboratory-scale system to measure the oxidation performance of the elemental mercury by non- thermal plasma （NTP） was set up and the effect of main gas constituents on the oxidation of elemental mercury under NTP atmosphere was investigated experimentally. The results indicate that the non-thermal plasma is a prospective approach to oxidize elemental mercury. The oxygen and water vapor promote the oxidation of elemental mercury significantly and 1.5% oxygen and 4% water vapor can achieve 97.4% and 92.5% of the mercury oxidation efficiency respectively. Active radicals generated by ionization, such as O, O3 and OH, play the crucial roles in oxidation process. The presence of carbon dioxide will increase the reductive atmosphere in flue gas and has a detrimental impact on the oxidation of elemental mercury. Under Hg/N2/O2/CO2/H2O complex atmosphere, due to the mutual interference between the active groups, the average oxidation efficiency is around 75%. Additive of HCl enhances the oxidation of elemental mercury and the mechanism of HCl dissociation under NTP atmosphere was also proposed here.

关 键 词：单质汞 低温等离子体 氧化增强 烟气氛围 

分 类 号：X701[环境科学与工程—环境工程]