长江三角洲冬季电厂排放对大气污染的影响

分析了长江三角洲地区电厂排放的基本特征并利用WRF-Chem模拟冬季大气污染状况，研究了冬季电厂排放主要污染物的特征及其对空气质量的影响，结果显示，长三角电厂排放的主要大气污染物为SO₂、NO_x及PM_2.5，2010年排放量可分别达到826.8、1475.6和137.3Gg，分别占长三角地区人为源总排放量的34%、38%和14%.冬季主要大气污染物（SO₂、NO₂、PM_2.5）浓度高值区分布在南京-上海，杭州-宁波一带.电厂对SO₂浓度贡献量（率）的空间分布与SO₂排放的空间分布较为一致，而NO₂、PM_2.5，其贡献量（率）的高值区主要分布在安徽、浙江和江西的交界处以及浙江省的东海岸.相对SO₂、NO₂，电厂对PM_2.5贡献量（率）较低，各地均在20μg/m³（15%）以下.污染时期电厂排放对模拟的PM_2.5和SO₂贡献率（6.9%、34.2%）较清洁时期（4.9%、20.7%）大，而对于NO₂，清洁和污染时期的贡献量没有明显差别，均在10μg/m³左右.冬季气温低、风速小及边界层高度低的特征不利于低层污染物的扩散，易导致重污染事件的发生.

The impact of power plant emission on air pollution during winter over Yangtze River Delta

The characteristics of emissions from power plant over Yangtze River Delta were analyzed, and major air pollutants in winter and their impact on air quality were then discussed based on WRF-Chem simulation. The results showed that the annual emissions of major air pollutants from power plant over Yangtze River delta were 826.8Gg, 1475.6Gg and 137.3Gg in 2010 for SO₂, NO_x and PM_2.5, respectively, accounting for 34%, 38% and 14% of total anthropogenic emissions. The high concentrations of major air pollutants (SO₂, NO₂, PM_2.5) were distributed in the city cluster of Nanjing-Shanghai and Hangzhou-Ningbo. The spatial distribution of power plant contribution from SO₂ was consistent with the emissions of SO₂, however, the high contributions of NO₂ and PM_2.5, were mainly distributed on the border of Anhui-Zhejiang-Jiangxi and eastern coast of Zhejiang province. Compared with SO₂ and NO₂, the contributions to PM_2.5 from power plant were relatively low, i.e. normally below 20μg/m³ in most regions (15%). The contributions of power plant emissions to the simulated PM_2.5 and SO₂ during polluted period (6.9%, 34.2%) were higher than clean period (4.9%, 20.7%), while, there were no significant differences for NO₂ between polluted and clean period, with the magnitudes as 10μg/m³. The conditions of low temperature, weak wind speed, and low boundary layer height in winter were not favorable to pollutant diffusion, leading to heavy pollution events.