为认知唐山大气颗粒物中典型二次污染化学成分水溶性无机盐的浓度水平、季节变化和粒径分布特征,于2010年9月~2011年8月使用惯性撞击式分级采样器对唐山大气颗粒物进行了分级采样,并用离子色谱分析了其中水溶性无机盐含量.结果表明,PM9(可视为可吸入颗粒物)和PM2.1(细粒子)中以3种水溶性无机盐SO24-、NO3-和NH4+为主,三者之和分别占PM9和PM2.1中水溶性无机盐总浓度的68%和77%;PM9和PM2.1中3种盐的浓度和在春、夏、秋、冬这4个季节分别为35.0、84.7、67.3、61.6μg.m-3和23.2、64.8、52.7、49.6μg.m-3,颗粒物中3种盐在细粒子中的赋存比例年均值分别为70%、75%和94%,夏季赋存于粗粒子中的比例显著高于其它季节.Ca2+和Mg2+全年均呈粗模态单峰分布.唐山大气颗粒物污染严重,控制燃煤、机动车尾气和生物质燃烧直排颗粒物的同时,要重点加强对气态污染物排放的控制,同时要控制地面扬尘和建筑灰尘.全面控制人为污染排放源,同时加强绿化和地面硬化、封闭式管理建筑工地,才有可能抑制住唐山市目前严重的大气污染.
To investigate the levels,seasonal variation and size distributions of water soluble inorganic components,samples were collected with an Andersen cascade sampler in Tangshan from Sep.2010 to Aug.2011,and were analyzed by IC.The results showed that the secondary inorganic components(SO2-4,NO-3 and NH+4) were the major contributors to PM9 and PM2.1,accounting for 68% and 77% of the total water soluble salts in PM9 and PM2.1,respectively.The total concentrations of these three ions in spring,summer,autumn,and winter were 35.0,84.7,67.3 and 61.6 μg·m-3 in PM9,and 23.2,64.8,52.7 and 49.6 μg·m-3 in PM2.1.About 70%,75% and 94% of SO2-4,NO-3 and NH+4 were found in the fine mode of aerosol,respectively.Ca2+ and Mg2+ were unimodal and mostly concentrated in the coarse mode.Those results indicated that the pollution caused by atmospheric particles is serious in Tangshan.It is urgent to control the anthropogenic emissions sources,such as vehicle emission,coal and biomass burning.Meanwhile,it is necessary to strengthen the greening and reinforce the management of the road construction.