哈尔滨市冬季雾霾天大气颗粒物污染特征分析

Analysis on the Pollution Characteristics of Atmospheric Particles during Haze Weather in Winter Harbin

为了研究哈尔滨冬季雾霾天大气颗粒物污染特征,于2015年11月3~4日特大雾霾天,对大气颗粒物进行取样,包括每小时质量浓度和数量浓度,同时利用离取样点最近的环保部门监测点数据进行了对比分析。确定出了其时间变化性、气象作用及不同粒度颗粒物比重。研究发现:此次雾霾由不利气象条件下人为源引起;雾霾天可吸入颗粒物浓度剧增,质量浓度PM_(10)/TSP平均为89.5%,其中PM_(2.5)的贡献很大,PM_(2.5)/TSP平均为64.1%,PM_(2.5)/PM_(10)平均为66.3%;不同粒度颗粒物数量、质量浓度变化规律基本一致,呈驼峰形曲线,早晚高,午后低;粒度为1~2.5μm颗粒雾霾天所占比例29.5%,是非雾霾天13.2%的两倍以上;雾霾的形成伴随着粒度小于0.5μm颗粒因凝结长大被大量消耗和粒度为0.5~2μm大量积累,这也是造成能见度降低的原因之一。

In order to study the pollution characteristics of atmospheric particles during haze weather in winter, the hourly mass concentration and number concentration of the atmospheric particulate matters were sampled during the seriously hazed days from No-vember 3 to 4, 2015. The comparative analysis was carried out using the data of monitoring point of environmental protection depart-ment which is nearest to the sampling site. Temporal variability, meteorological effect and concentration ratio of the particulate matters were respectively identified. The results showed that the haze was mainly caused by the anthropogenic sources under adverse weather conditions. The mass concentration of the inhalable particulates（PM10）increase sharply during the formation and maintaining of haze, the mass concentration of PM10 accounts for 89. 5% of TSP on average. Among the PM10 , the contribution of PM2.5 was significantly e- normous with PM2.5/TSP of 64. 1% and PM2.5/PM10 of 66. 3% on average. The mass concentration and number concentration of par-ticulate matters with different particle size presented the similar changing trend. The trend line showed a hump shape with the low in midday and the high in the morning and at night. 1 -2. 5μm particulate matters concentration accounted for 29. 5% of TSP in haze days, which was more than twice as likely to that in non - haze days. Haze formation process accompanied by most particulate matters of 〈0. 5μm consuming due to its condensation and growth. The Haze formation process also accompanied by accumulation of a large amount of 0. 5 -2μm particulate matters, which was one of the important factors causing the visibility deterioration in haze day.