【作者】 黄永健；

【导师】 周蓉生； 张成江； 汪云亮；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2002， 博士

【摘要】 汞及其化合物具有很强的生物毒性，汞危害问题已经引起国际环境、卫生界的极大关注。汞主要通过自然和人为排放而进入大气，其中燃煤排放是造成大气环境汞污染的重要因素。我国拥有丰富的煤炭资源，汞的储量也位居世界前列，因而对汞污染的研究更具紧迫性。以往的研究集中关注气态汞的行为，而对与气溶胶相联系的颗粒汞研究还显得非常薄弱，但是在某些情况下，颗粒汞是大气中汞的重要存在形式，而且在汞的区域性环境循环中具有重要的地位，加强颗粒汞的研究是汞污染研究的发展方向之一。 环境问题的解决需要多学科的参与。应用地球物理和地球化学的原理和方法，可以研究有害元素的富集或亏损规律，预测环境的质量和变化，反映人类活动对地质介质的影响，为污染防治及资源的可持续利用提供对策。运用汞气测量和核物探相结合的物探方法进行颗粒汞的研究具有灵敏度和准确度高、多元素同时测定的特点，利于研究汞与其它污染元素之间的共伴生关系、追踪污染源，研究环境效应。 本论文是在参加在国家自然科学基金项目“大气气溶胶中汞污染及环境效应”(编号：49974040)的基础上完成的。本文建立并运用环境物探方法，以城市工业区和高汞地球化学异常区等典型环境类型作为研究对象，详细研究其气溶胶汞污染特征，取得如下创新性成果及认识： (1)以汞气测量和环境核物探方法为主建立了气溶胶汞污染研究中的环境物探方法，论证了该方法运用于气溶胶汞污染研究的可能性，为该方法的成功运用打下坚实的基础。 (2)分析了气溶胶富集因子计算中参比物质的选择问题，首次将地球化学基线理论引入到富集因子的计算当中，发展了一种新的富集因子计算方法。以建立的成都地区土壤的汞地球化学基线为基础，重新计算了大气飘尘样品的汞富集因子，使其能够更科学地评价人为活动对气溶胶汞含量所造成的影响。 (3)应用环境物探方法对西南三省的部分煤炭样品、成都市燃煤电厂的燃煤及其燃烧产物进行了分析，进一步了解了本地区煤炭中有害有毒元素的含量水平，以及煤炭燃烧前后物质的组成变化特征，证实了Se、Sb、As等元素可以作为燃煤污染物的标志性元素，为颗粒汞污染源追踪的研究工作提供了依据。 (4)对成都市工业区气溶胶汞污染的特征进行了详细的研究，内容包括颗粒汞的季节变化、昼夜变化以及在不同粒度的气溶胶中的分布，并运用因子分析等受体模型，研究了本工业区大气飘尘中汞含量的影响因素。研究表明，本工业区面临着严重的汞污染形势，气溶胶中汞含量远远超过颗粒汞的自然本底值，也高于国内外其他工业区的污染水平，并已成为本区域大气汞沉降的主要形式之一。气溶胶汞含量与气溶胶的质量浓度密切相关，并受到气象条件的严格制约，冬季污染程度高于夏季。大气飘尘的汞含量水平集中受到燃煤飞灰的控制，要降低大气飘尘中颗粒汞的含量，必须降低煤炭的消耗或者采取除汞技术。 （5）通过贵州务川汞矿区及背景点的气溶胶汞污染研究表明，汞矿区气溶胶汞污染特1征与城市工业区明显不同。汞矿的冶炼活动本身产生的气溶胶汞污染的地域分布比较有限，但是其排放的气态汞会在气溶胶上产生严重的吸附作用，从而使得矿区气溶胶中的汞异常偏高。背景点大坪的气溶胶汞污染特征与矿区的汞污染特征有明显的差别，大坪气溶胶中的汞主要来源干风沙扬尘，受到汞矿冶炼和开采活动影响的较小。更多还原

【Abstract】 As mercury and its compounds have strong biological toxicity, the environmentalists and hygienists have pay more and more attention about the problem of mercury hazards. The situation of mercury pollution is serious throughout the world, especially for the atmospheric mercury pollution caused by the combustion of coal. China has abundant resources of coal and mercury and faced more serious problem of mercury pollution. Former study mainly focus on the Hg? and the study of paniculate mercury is relatively poor and not systematical. But in some cases, particulate mercury is die important form of atmospheric mercury, and plays a notable role in the regional mercury cycle. There is a tendency to strengthen the study of particulate mercury.The problem of environmental pollution calls for the multi-disciplinary research. With the principle of geochemistry and geophysics, peoples can understand how the hazard substances transform in the environment, so as to forecast the quality and change of the environment, to show the affects of human activity, and to provide the resolution for the sustainable utility of resources and prevention and cure of pollution. With the joint methods of measurement of mercury vapor and nuclear geophysics, one can do multi-element analysis with high sensitivity and accuracy, which is favorable to study the environmental effects and concomitance of mercury and other pollutants, to trace the pollution sources.With the support of project "Mercury Pollution in the Atmospheric Aerosols and its Environmental Effects " granted by National Science Funds of China, the paper development and utilize the methods of the environmental geophysics to study the characteristics of mercury pollution in the atmospheric aerosols of very typical environments including Chengdu industrial area and mercury deposits in Wuchuan of Guizhou province. The main researching results are as follows: (1) Based on die technology of measurement of mercury vapor and environmental nuclear geophysics, the paper established the environmental geophysical method used in the mercury pollution study of atmospheric aerosols, and demonstrate the feasibility of employment of such method, which provide the foundation for the later research.(2) The paper discussed the choice of references used in the computation of enrichment factor of aerosols, developed a new method to compute the enrichment factor with the theory of geochemical baseline. Based on the mercury baseline of soil in the Chengdu area, the mercury enrichment factors of suspended matter of Chengdu industrial area are computed again better to show the degree of particulate mercury pollution caused by the human activities.(3) With the application of environmental geophysical method, coal samples from Southwest of China, and combustion residue of coal and coal samples from Chengdu power plant are analyzed. It is proved that such elements as Se, Sb and As can be seen as the indicator of combustion pollutants of coal, which offer a better condition for the mercury pollution in the aerosols.(4) With the application of environmental geophysical method, the paper studied the characteristics of mercury pollution in the aerosols of Chengdu industrial area, which include both the seasonal, day and night variation of particulate mercury and the distribution of particulate mercury in the different grades of aerosols. Also the factor analysis model is used to determine the main factor affecting the mercury level of atmospheric suspending dust ( radius less than 10 n m). The results show that the industrial area is now facing the serious situation of mercury pollution, and the mercury level of aerosols is much higher than the background level of particulate mercury, and also higher than those of other industrial both inside and outside of the country. Particulate mercury has become one of the main form of atmospheric mercury deposition, which keeps good correlation with the mass level of aerosols and is restricted by the meteorological conditions with higher level in the winte更多还原