Volume 16, No. 7, July 2016, Pages 1651-1664 PDF(1.52 MB)
PM2.5 Chemical Composition Analysis in Different Functional Subdivisions in Tangshan, China
Wei Wen1,2, Shuiyuan Cheng1,4, Lei Liu3, Xufeng Chen5, Xiaoqi Wang1, Gang Wang1, Song Li1
1 College of Environmental & Energy Engineering, Beijing University of Technology, Beijing 100124, China
2 Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei, Chinese Meteorological Administration, Beijing 100089, China
3 Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS B3H 4RZ, Canada
4 Collaborative Innovation Center of Electric Vehicles in Beijing 100081, China
5 Tangshan Environmental Monitoring Station, Tangshan 063000, China
- The 24-h PM2.5 samples were collected at two different functional subdivisions.
- PM2.5 concentrations in the industrial site were higher than that in the residential.
- The residential subdivision had a relatively higher [NO3–]/[SO42–] ratio.
- At both subdivisions, winter had the highest OM concentration while summer had the lowest.
In this study, the 24-h PM2.5 (i.e., the fine particles with aerodynamic diameter of ≤ 2.5 µm) samples were collected at two different functional subdivisions in the city of Tangshan during the period of July 2012 to April 2013. The months of July, October, January, and April were chosen to represent four different typical seasons. The total PM2.5 mass was measured. PM2.5 samples were used for the analysis of inorganic elements, ions, Organic Carbon (OC) and Elemental Carbon (EC). PM2.5 concentration in the industrial subdivision were generally higher than those in the residential subdivision. The annual mean PM2.5 concentrations were 196 µg m–3 for the industrial subdivision and 116 µg m–3 for the residential subdivision. The coefficients of divergence (CD) calculated for spring, summer, autumn and winter were 0.67, 0.35, 0.65, and 0.33, respectively. The Enrichment Factor Method (EFM) was used to help determine the original sources of these inorganic elements. Secondary water-soluble ions (SO42–, NO3–, and NH4+) were the major water soluble ions in the PM2.5 of Tangshan, and they are present in the atmosphere as (NH4)2SO4 and NH4NO3. The Sulfur Oxidation Ratio (SOR) and Nitrogen Oxidation Ratio (NOR) show that the precursor conversion ratio was highest in summer. At both subdivisions, winter had the highest monthly average OM concentration while summer had the lowest.
PM2.5 pollution; Chemical composition; Residential subdivision; Industrial subdivision.