| Total suspended particulates are the primary pollutants influencing on the quality of ambient air. The inorganic component is an important part of TSP. In this paper, the different source and the contribution of TSP have been decided through analyzing TSP's content and source of inorganic component, which provides a solid theoretical basis for further research on the harmfulness to the environment made by atmospheric particulates and the way to improve ambient air environment.The mathematical model of analyzing environmental pollutant source can be broadly divided into receptor model and proliferation model. The receptor model has been used widely because it does not relay on source of emission, weather, terrain and other data and dose not track particulates'moving process, which means that it avoids the difficulties of calculating in proliferation model. Chemistry-statistical method and microscopic method are two main research methods in receptor model. This paper analyzes and compares the preconditions, advantages and disadvantages of different method, chooses the applied Chemical Mass Balance (CMB) accepter model and the scanning electron microscope (SEM) in microscopic method, and applies to study the typical atmospheric particulates in four cities of JiLin province.CMB receptor model focuses on researching emission source's contributions to receptor without considering chemical changes and chemistry reaction dynamics results in the particulates transmission process between emission source and receptor, but by determining directly chemical component of samples ,which comes out from receptor, to infer the kinds of emission source. This way is recommended as an important method to recognize atmospheric particulates by United State and China mainland environmental protection because its clear theory and applied calculation. Good research results have been achieved by applying CMB to many cities. However, since in most cases the study focused in one city, no comparison has been made in different cities. This research aims at carrying out comparative study on TSP. It is different from citys and times by doing research in four cities in the same region. According to geographical features and characteristics of cities in JiLin Province, JiLin, BaiCheng, TongHua, SiPing and Changchun have been chosen to conduct our research.This study collected the source and receptor samples of TSP. It is distinguish between heating period(February 2005) and non-heating period (September 2005) in JiLin, BaiCheng, SiPing and TongHua The points of receptor samples in each city are selected mainly from state-controlled atmosphere monitoring stations. JiLin selects four sampling points and other cities select two points each one, therefore ten sampling points in total. Here 156 samples are research objectives of dust, road dust , construction dust, coal dust and soil dust. Collected samples were analyzed by X-ray fluorescence spectroscopy to identify inorganic component in the receptor samples. According to related documents and pollutant characteristics in this study, we analyzed about 23 kinds of elements ,such as Al, As, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Nb, Ni, P, Pb, Rb, Si, Sr, Ti, V, Zn and Zr. The result proves that main inorganic elements of TSP is such as Si, Al, Fe, Ca, Mg, K, Na, Ti, P, Mn, Zn. For the mass concentration sum of the 11 kinds of elements, there are 17 PT over 20 kinds of elements for 95%. Also, there are 2 PT over 20 kinds of elements for 90%. By analyzing Elements spectra of the source and the receptor in these four cities. it is obvious that content of Si is higher than other inorganic elements. Si is the primary element that constitutes the soil particles and pozzuolana, and raising dust is mainly contributed by soil particles. So, it can be justified that raising dust and soil dust are the major source of TSP in these four cities. Northeast locates in Songliao plain, because the winter is long, cold and dry, the wind is strong and the short period of vegetation, the content of Si in source and receptor specimen remains high. It can be known that the geographical characteristic has a great effect on TSP.The 20 samples collected from four cites show that 10 points mass concentration of TSP exceed the third class national standard, the PT take 50 percentage of total observation points. About 30 percentage of observation points, there are 6 PT exceed the second class national standard. There are only 20 percentages of observation points below the second class national standard. The study presents those four cites'serious air condition, which need to take effective control measure.Using CMB8.2 receptor model to analyze the source of TSP in ambient air, the result indicates that:1. In heating term, pollution sources contributed to TSP in Jilin from large to small is as follows: blowing dust, soil karaburan, and coal burning dust; pollution sources contributed to TSP in Bai Cheng, from large to small is as follows: soil karaburan, coal burning dust and construction dust, the most TSP contribution in Tong Hua are blowing dust, coal burning dust and soil karaburan, and blowing dust is main pollution source; The main sources in Si Ping are blowing dust and road dust. According to analysis results, it states that in heating time most of cities'road dust, blowing dust, and soil karaburan make the bigger contribution on TSP, but it's unobvious that the effects of construction dust and burning coal dust on TSP. They state that these cities'transportation and soil exposedness should be improved. Comparing Bai Cheng which is located in flat area with Tong Hua which is located in mountainous area, the different level contributions of their soil karaburan make on TSP, they relate with two places'geography positions and the differences of weather conditions. Burning coal source hasn't been main source in heating term; it states that the controlment and management of burning coal pollution has got enough efforts. Many burning coal corporations improve production techniques, decrease amount of coal use, boilers smoking has reached emission level, so they cause that the effects burning coal dust on atmosphere is decreased. The influences construction dust for TSP contribution is unobvious, because there are few constructions in north cities, and also refers to urban infrastructure construction condition and urban development situation.2. In Jilin City, various types of pollution which contribute to TSP during non-heating period in terms of descending order are construction dust, soil dust, road dust, raising dust and burning coal dust. The three sources of pollution that make the greatest contribution in Baicheng City are: soil dust, road dust and rising dust. among which the soil dust is main pollution source. The three types of pollution that contribute the greatest to TSP in Tonghua City are: road dust, burnt coal dust and soil dust. The main sources of pollution in Siping City are: rising dust, construction dust and soil dust. According to the analysis above, we see that the construction dust in Jilin City during a non-heating period makes the greatest contribution to TSP and has something to do with the status of the city's infrastructure and its development. That the soil dust in Baicheng City, the road dust in Tonghua City and the rising dust in Siping City contribute the greatest to TSP showing that it is closely related to the natural environment, climate and geographical location of these cities. The soil dust problem has an important climatic impact on all of these cities due to the strong sand storms and droughts every autumn. Besides, the low ratio of vegetation coverage is also a reason. Over-cultivation, deforestation, and soil-erosion in these regions have helped to increase the amount of dust in the atmosphere.3. The results are the same after the analysis of the whole year TSP for the four cities during heating and non-heating periods. The soil dust contributes more to TSP in Jilin and Baicheng, the road dust contributes more to its air pollution in Tonghua and the rising dust of SiPing has more effect on its TSP. Meanwhile, it shouldn't be ignored that the road dust in Jilin as well as the burnt coal dust in Baicheng and Tonghua have a strong affect on their air quality. However, the construction dust of the four cities apparently doesn't affect TSP.Through the research and analysis we see geographical characteristic plays a dominant part in TSP parse. But, the dominant industries in different regions contribute to the share ratio of TSP to some extent.Results of source analysis also indicate that different pollution types and sources in different cities contribute differently to TSP, and their characteristics are different too. Even in the same city the pollution sources in different seasons contribute differently to TSP. Thus, different emphasis and measures should be chosen in reducing and controlling air pollution. So as to improve thoroughly the air quality, more human and financial resources should be invested in dealing with those sources of emission which seriously pollute the environment and contribute more to the suspended dust particulates in the air. The analysis indicates that many types of human activity increase the degree of air pollution.Considering the representative and similar features of the cities'geographical location and climate in the research we have selected one point site in Changchun City to collect samples of TSP, PM10, PM2.5, and analyzed the contents of inorganic elements in those samples by means of ICP-MS. As a result we have detected the fourteen elements such as Na, Mg, Al, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Sr, Ba and Pb. According to the results of the analysis, the concentration of particulates is mostly composed of the following six elements Al, Ca, K, Mg, Fe and Na. The daily average concentration of the six elements in TSP and PM25 approaches, or even surpasses the 1μg/m3 level, and the concentration of these elements in PM10 approaches or surpasses the 10μg/m3 level. The total concentration of these six elements is found to account for 95.3%, 91.6% and 90.6% of the fourteen elements in TSP, PM10, and PM2.5 respectively. The elements of Al, Na, K, Ni, Pb mainly exist as large particulates while Ca, Fe, Zn, Sr, Ba are mostly contained in PM25. By analyzing Elements spectra of Inorganic in different radius'particles, Elements spectra of Inorganic in TSP and PM10 have nothing in difference, but TSP is different from PM2.5.Via the correlative analysis and t test, we can see that the relativity of the elements contained in TSP and PM10 are the best, followed by PM2.5 and PM10. So in pollution monitoring in Changchun, we can obtain the relative contents of the various elements in PM25 through the analysis of the elements content in PM10, and get a better understanding of PM2.5 pollution so as to protect our health more effectively.SEM is applicable to analyzing dust aerosol which has a clear configuration, and can observe in detail information of the particulates directly. Also the particulates can be processed with semi-quantitative and qualitative analysis. Via SEM, we can observe that the TSP have following shapes: Spherical, filament, strip, flocculation, massive and other irregular shapes. The preliminary analysis indicates that rising dust, road dust, soil dust and construction dust are main sources of TSP in the air of the four cities. Dust aerosols play a major role in the global radiation changes. The variable effects of dust aerosol change the energy input to the climate and cause an uneven distribution of warming and cooling effects. Very little documentation is available about atmospheric dust aerosol and studies have been unable to prove that it has increased since the onset of the industrial age. In our present research the visual analysis by SEM serves to assist the particle source apportionment and it verifies the analysis results of CMB receptor model. It has been shown to be the most effective research method for particle source semi-quantitative analysis.
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