环形扩散管法测定北京市大气中HNO_3和HNO_2的条件优化与应用研究  

Conditions optimization and application for determining concentrations of HNO_3 and HNO_2 in atmosphere of Beijing by annular denuders method

作　　者：亓学奎[1] 王欣欣[1] 张婷婷[1] 汪雨[1] 刘艳菊 武彦文[1] 孙珍全[3] QI Xuekui WANG Xinxin ZHANG Tingting WANG Yu LIU Yanju WU Yanwen SUN Zhenquan(Beijing Center for Physical and Chemical Analysis, Beijing 100089, China Beijing Milu Ecological Research Centre, Beijing 100076, China Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, Chin)

机构地区：[1]北京市理化分析测试中心,北京100089 [2]北京麋鹿生态试验中心,北京100076 [3]中国科学院理化技术研究所,北京100190

出　　处：《环境工程技术学报》2017年第1期120-124,共5页Journal of Environmental Engineering Technology

基　　金：国家自然科学基金项目(41475133);北京市科学技术研究院创新团队项目(IG201307N);北京市科学技术研究院青年骨干计划(2012-008)

摘　　要：为研究北京市大气中HNO_3和HNO_2的污染特征,进行了环形扩散管法涂层溶液最佳浓度确定条件优化试验,并于2014年秋季在北京市开展了应用研究。结果表明:环形扩散管中Na_2CO_3涂层溶液的浓度为2%时,大气中酸性气体的去除率达到90%以上;利用优化的环形扩散管方法对北京市城区大气中的HNO_3和HNO_2浓度进行了测定,观测期间大气中HNO_3和HNO_2的浓度分别为0.77~3.23和1.12~5.51μg/m^3,平均值分别为2.33和2.96μg/m^3。研究区大气中HNO_2浓度高于HNO_3,一方面可能由于采样期间光照较弱,HNO_2光解能力降低,另一方面可能由于采样点位于交通干道附近,来自汽车尾气排放的NOx发生均相和非均相反应。大气中HNO_3浓度在雾霾天时最高,其次为晴天;HNO_2浓度也是雾霾天最高,且远高于晴天。In order to study the pollution characteristics of HNO_3 and HNO_2in ambient air of Beijing City,the experiments for determining the optimal concentrations of annular denuders coatings were performed, and application study carried out in Beijing in the autumn of 2014. The results showed that when the concentration of Na_2CO_3 coating solution was 2%,the removal rate of acid gases in the atmosphere reached over 90%. The concentrations of HNO_3 and HNO_2in air sampled in downtown Beijing were determined by the optimization approach. The concentrations of HNO_3 and HNO_2in the measurement period ranged from 0. 77 to 3. 23 μg/m3and from 1. 12 to 5. 51 μg/m3,with an average value of 2. 33 μg/m3and 2. 96 μg/m^3,respectively. HNO_2 concentration was higher than that of HNO_3 in the study area. The weak light during sampling might result in HNO_2 photolysis reduction. Also,because of the sampling point nearby trunk road,the homo- and heterogeneousreactions of NOxfrom automobile exhaust may lead to a higher HNO_2 concentration. The highest concentration of HNO_3 occurred in haze day,followed by sunny day,while HNO_2 had the highest concentration in haze day,which was far more than that in sunny day.

关 键 词：环形扩散管 涂层溶液浓度 硝酸气体 亚硝酸气体 北京 

分 类 号：X511[环境科学与工程—环境工程]