The Source Apportionment And Numerical Simulation Of The Inhalable Particles In Xuzhou City

The source of the inhalable particles was analysed by chemical mass balance model (CMB)in Xuzhou urban areas.The contribution value and contribution rate of each source to PM₁₀was obtained.It provides an important basis to control PM₁₀pollution in Xuzhou city. The typical street canyon gas flow field and the PM₁₀pollutant density distributed situation were simulated by the Fluent software.It provides a theory basis to reduce PM₁₀pollution by the reasonable planning and designing street canyon layout.In order to carry on the research of source apportionment of the inhalable particles in Xuzhou,The samples of six sources were collected,such as soil dust,construction dust,road dust,smelting dust,coal dust and urban dust.Three function sampling points were set up in the Tongshan veterinary hospital,the Huai tower and the Yellow River new village, separately in September 2007 and January 2008,gathered the inhaled particles acceptor sample.After source and receptor samples were pretreated,determined the inorganic elements, the water-soluble ion,the carbon element and the polycyclic aromatic hydrocarbons four kinds of chemical composition's content,obtained the PM₁₀source components spectrum and the receptor components spectrum in Xuzhou.Using chemical mass balanced model(CMB) to carry on source apportionment to PM₁₀and obtain the contribution value and contribution rate of each source to PM₁₀.The whole year source apportionment result of PM₁₀in Xuzhou indicates:the important source of PM₁₀is urban dust 40.1%;secondary particles(sulfate and nitrate)31.3%;soil dust 14.0%;coal dust 8.5%;smelting dust 4.1%;Other 1.9%.In the identification of the source category,the focus should be to control urban dust,secondary particles and coal dust.The source apportionment result of PAHs shows that the annual contribution rate of coal dust is 64.00 percent and coal dust is a major contribution source of PAHs.The typical street canyon gas flow field and the PM₁₀pollutant density distributed situation were simulated by the Fluent software.The establishment model included the different shape's building in the street canyon.The findings indicate that different shape building structural change street canyon wind speed distribution,thus it has very tremendous influence on the pollutant distribution in the street canyon.