| Shanghai has been one of the largest cities with rapid economic development, which processes the most complete industry categories, the largest energy consumption intensity and the highest density of emission sources. During the past decades, with the application of air pollution control measures, such as the adjustment of industrial structure and layout, alternatives of cleaner energy and comprehensive pollution control on the industrial parks, the ambient air quality in Shanghai has been improved generally. The annual average of daily concentration for PM10 was 0.084mg/m3 in 2008, which has decreased by 15% comparing to 2004. The annual average of daily concentration for SO2 has decreased by 5.6%, The annual average of daily concentration for NO2 has decreased by 9.7%. However, the air pollution is still serious in shanghai comparing with the other international megacity. The pollution level of PM10 is 2 to 5 times of that in developed cities. Furthermore, the annual daily concentration of fine particle matter (PM2.5) is about 0.050 to 0.059 mg/m3, which is 3 or 4 times greater than the annual average guideline value(0.015 mg/m3) set by World health organization. The fine particle pollutiion represented by PM2.5 has become the key issue of air quality improvement in Shanghai.In this study, the PM10 and PM2.5 in ambient air was observed in shanghai. With the development of air pollution emission invertory and its contribution as the basic research content, combining with the on-site monitoring, laboratory analysis, statistical analysis and numerical models, the spatial and temporal distribution of fine particle aerosol pollution, the chemical composition, formation mechanism and source identification were analyzed. In this study, according to the comprehensive identidication of pollution sources, the methods and measures of emission inventory quantification were applied and revised for the key pollution plant, combining with the national pollution census and the innovative methods for verifying the emission sources of key national controlled enterprises. The quantitative changellenge for fugitive emission of VOCs in petrochemical industry was studied and practiced. Additionally, the air pollution emission inventory in shanghai was developed, which contained the criteria pollutants of PM, PM10, PM2.5, SO2, NOX, CO, VOCs and NH3 aiming for aerosol pollution control. The grid resolution of this emission inventory is for 1km×1km and the height is 1km, including 33 kinds of industrial point sources (12896 industrial enterprises), 20 kinds of domestic and industrial point sources, as well as the mobile sources such as motor vehicles, ships, aircraft and trains.As shown by emission inventory of 2006, the total mass of all kinds of emission sources are 582,000 tons for PM, 279000 tons for PM10, 111000 tons for PM2.5, 564000 tons for SO2, 464000 tons for NOX, 1417000 tons for CO, 574000 tons for VOC, 14000 tons for NH3, which is the highest in the world. Area emission is the major sources for PM, PM10, PM2.5, VOC and NH3. Point emission is the major source for SO2 and NOX. Mobil emission is the major source for CO, which contributed 46% of the total. The road dust is the major source for primary pollutants such as PM, PM10 and PM2.5, which contributed 54%, 45% and 26% respectively. The power plant and the fuel-firing of industry, contributing 57% and 12% of the total and was the key source of SO2 which would transform into the secondary aerosol pollutant. The major source for NOX is power plant and vehicles, which contributed 36% and 18% of the total mass in shanghai. The major sources for VOCs pollutant are coatings, tank and motor vehicles production process, which contributed 28%, 23% and 16% respectively. The major source of NH3 pollutant is from the breeding of livestock feeding, poultry and industrial process, which contributed 66.7% and 19.7% of the total emission mass in Shanghai.In this study, MODEL3-CMAQ was used to analyze the source of the pollution in winter in shanghai, the scenario simulation was developed to analyze the contribution of different emission sources to the fine particle pollution in shanghai. The results showed that the concentration of PM10, PM2.5 in Shanghai was mainly influenced by area emission which contributed 68.3% of the concentration, and the mobile emission as well as the non-power plant next. The power plant emission was the major factor caused the continual high concentration of SO2, which contributed the 32.1%, secondly is mobile and non power plant emission. The contribution of sources outside Shanghai was 15.3%. The mobile source is the major factor caused the high concentration of NO2, next is power plant and non power generating industrial plant.In this study, a great number of PM10 and PM2.5 data from ambient air monitoring network and aerosol sampling was analyzed. The results showed that the temporal variation exhibited high concentration in winter and spring (Jan. Mar. April, Nov. and Dec), low concentration in summer and autumn (Jul, Aug and Sep). The diurnal variation showed two peaks. And the spatial variation showed that low concentration of PM10 in eastern coastal areas and high concentration in northwestern areas. The average concentration of PM25/PM10 was more than 0.5 in Shanghai. The variation of gaseous pollutants was different from that of particle matter in different pollution episode. The SO2/PM10 (0.38) value in serious haze days was significantly lower than that in good or moderate days, while PM2.5/PM10 value significantly increased to 61%. The proportion of water-soluble components in PM2.5 accounted for 59%. SOR and NOR was to 0.67 and 0.61, respectively, which meant the sulfate, nitrate and ammonium transformed from primary SO2 and NOX. It was the key mechanism for the high concentration of PM2.5 in Shanghai. In the high pollution days influenced by long distance transport of dust storm, the ratios of SO2/PM10,NO2/PM10,PM2.5/PM10 in ambient air of Shanghai have decreased to 0.066, 0.073 and 0.155. The values of SO2/PM10,NO2/PM10 and PM2.5/PM10 could be used as the important index to identify the dust day, non-dust day or haze day in Shanghai.The results of this study revealed the fine particle aerosol characteristics and changes in Shanghai. The characteristics, source and formation mechanism of aerosol, especially under the typical serious haze pollution and its impact on air quality, impact by the long distance transport of dust storm was clarified. |
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