乌鲁木齐气溶胶粒径分布及细颗粒物(PM_(2.5))浓度变化分析  

Analysis on the Size Distribution of Atmospheric Aerosol and the Mass Concentration Change Characteristics of Fine Particulate Matter(PM_(2.5))

作　　者：刘新春[1,2] 陈红娜 赵克蕾 钟玉婷[1,2] 闫景武 

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所//新疆树木年轮生态实验室//中国气象局树轮年轮理化研究重点开放实验室,新疆乌鲁木齐830002 [2]塔克拉玛干沙漠大气环境观测试验站,新疆塔中841000 [3]乌鲁木齐市机动车排污监督管理办公室,新疆新疆乌鲁木齐830054 [4]北京乾润开元环保科技有限公司,北京101300

出　　处：《生态环境学报》2016年第4期605-613,共9页Ecology and Environmental Sciences

基　　金：新疆维吾尔自治区自然科学基金项目"塔克拉玛干沙漠与帕米尔高原沙尘气溶胶特性观测研究"

摘　　要：利用乌鲁木齐市中心区域气象局和黑山头2013年1月1日-2014年2月28日期间Grimm180在线监测数据,对乌鲁木齐市大气气溶胶数浓度和PM_(2.5)质量浓度的分布特征及其影响进行了分析,为深入了解乌鲁木齐市颗粒物污染现状,确定乌鲁木齐市大气污染治理重点,制定大气污染防治规划提供依据。结果表明,(1)气象局和黑山头气溶胶数浓度分布趋势一致,0.25~0.28μm之间的粒子数浓度最大;整体趋势表现为双峰型,第1峰出现在0.30~0.35μm之间,峰值分别为467.0和455.4 particle·cm^(-3);第2峰出现在4.0~5.0μm之间,峰值较小;粒径小于2.5μm的粒子数占到了粒子总数的99.88%;在粒径0.25~0.45μm范围内冬季气溶胶粒子数浓度最高,在粒径>0.45μm范围内秋季气溶胶粒子数浓度最高;在粒径0.25~1μm范围内夏季气溶胶粒子数浓度最低,在粒径>1μm范围内冬季数浓度最低;0.25~0.5μm粒径段内粒子占粒子总数的比例大小顺序为冬>春>夏>秋;0.8~2.5μm之间不同粒径段的粒子占粒子总数的比例大小顺序为夏>秋>春>冬;PM_(2.5)数浓度小时变化采暖期表现为双峰型,非采暖期为不太明显的三峰型。(2)观测期间气象局和黑山头PM_(2.5)平均质量浓度分别为61.77,43.42μg·m^(-3),日平均值超标率分别是30.81%和16.44%。采暖期气象局PM_(2.5)质量浓度小时变化呈现单峰,在19:00─21:00出现峰值;黑山头则呈现双峰,在6:00-8:00出现峰值,20:00出现一个不太明显的小峰;非采暖期气象局与黑山头PM_(2.5)质量浓度小时变化趋势一致,均表现为双峰型。两个站点PM_(2.5)质量浓度的季节变化均表现为冬季>秋季>春季>夏季,特殊的地理位置和不同季节污染源的排放强度、气象条件是导致PM_(2.5)质量浓度随季节变化的主要原因。Based on online monitoring data of atmospheric aerosol form January 1, 2013 to February 28, 2014 with ambient dust monitor (Grimm 180) at Meteorological Administration (MA) and Heishantou (HST) in the center of Urumqi, distribution of number and mass concentration data of inhalable particles were analyzed. The results showed that, (1) Aerosol number concentration distribution had the same trend at MA and HST. The maximum values of particle number concentration were between 0.25 and 0.28μm. Aerosol size distribution showed a bimodal shape with the first peak between 0.30 and 0.35μm and the second peak between 4.0 and 5.0μm. Aerosol particles with the diameter less than 2.5μm in the number of particles accounted for 99.88% of the total number concentration. The number of particles within 0.25~0.45μm in winter was the maximum value, while the number of particles larger than 0.45μm in autumn was the maximum value. The number of particles within 0.25~1μm in summer was the minimum value, while the number of particles larger than 1μm in autumn was the minimum value. Diurnal variations of PM2.5 number concentration presented a bimodal shape during heating period and a trimodal shape during non-heating period. (2) The average concentration of PM2.5 at MA and MSS were 61.77 and 43.42μg·m-3, and the excessive rate were 30.81% and 16.44%, respectively. During heating period diurnal variations of PM2.5 mass concentration presented a single peak which appeared in 19:00 to 21:00 at MA, but a bimodal shape at HST. While during non-heating period diurnal variations of PM2.5 mass concentration presented a bimodal shape at two sites. The seasonal distributions of PM2.5 mass concentrations were winter> autumn> spring> summer at two sites.

关 键 词：大气气溶胶 数浓度 质量浓度 粒径分布 细颗粒物(PM2.5) 

分 类 号：X51[环境科学与工程—环境工程]