【作者】 李洪伟；

【导师】 颜事龙； 崔龙鹏；

【作者基本信息】 安徽理工大学 ， 应用化学， 2006， 硕士

【摘要】 本文重点调查研究了煤电化工业对土壤重金属污染。在淮南矿区选择5条土壤采样线,系统采集淮南化工区内土壤样品和新矿井区（新集矿井区）内煤矸石与粉煤灰堆附近的土壤样品。采用HNO₃+HClO₄+HF湿式消化法对样品进行消化处理,使用现代环境微量分析技术美国IRIS Intrepid电感耦合等离子体全谱直读光谱仪（ICP—AES）测定了土壤中21种元素含量,采用加拿大沉积物标样（LKSD-1）控制分析质量。进而,科学合理筛选出6种具有环境意义的微量元素（Co、Cr、Cu、Ni、Pb、Zn）,以总量法、对比法、相关系数法和富集系数法综合评估了这些元素的富集和污染水平。研究结果表明:新集矿井区土壤中Co、Cu、Ni和泉山化工区土壤中重金属Co和Ni表现显著富集和污染贡献。新集矿井区内粉煤灰堆置对土壤的Co、Cr、Cu、Ni、Pb、Zn污染均高于煤矸石。就全矿井区而言,矿井区土壤已表现来自煤炭开发利用导致的重金属污染贡献,且具有累积性。但矿井区土壤中分析的重金属元素均未超过国家土壤二级污染标准,这说明煤矸石中重金属向周围土壤的迁移是缓慢过程。不同矿井区土壤中重金属含量随开采历史及堆积煤矸石风化时间长而呈现递增的趋势,且Co、Cu、Zn、Ni、Pb表现相对较强的迁移性,其含量在部分矿井区土壤中超过国家土壤一级污染标准。 同时,本文选取代表性土壤样品,采用欧共体标准测量与检测组织的BCR三步逐级提取法分析了土壤中6个重点元素的化学形态,采用BCR土壤标样（BCR-701）控制分析质量。研究结果表明:Co、Cu、Mn存在可交换态,表现有相对较强的迁移性和生物可利用性;Pb主要以还原态的形式存在,表明具有较强的潜在危害性;Zn、Cr主要以氧化态和残渣态形式存在,Ni主要以残渣态的形式存在,这些元素的迁移性较弱。因此,在矿区生态农业建设中重金属污染应给予重视。更多还原

【Abstract】 This paper focus on the investigation of hazardous heavy metals in soil in Huainan coal-electricity-chemical industrial district A case study on heavy metals in soil was conducted through the investigation of five soil sampling routes nearby coal-mining spoil dump and coal combustion ash disposal pond in new coal-mining district （i.e. Xinji coal-mining district） and Quanshan chemical industry district respectively. Soil Samples were taken systematically from land in above districts and were digested by HNO₃+HClO₄+HF, and 21 trace elements were analyzed by IRIS Intrepid inductively coupled plasma—atomic emission spectrometry （ICP-AES） in the Institute of Soil Science, CAS, and certified lake sediment samples（LKSD-l） from Energy Mines and Resource Canada were used for analytical quality control. 6 trace elements （Co、Cr、 Cu、 Ni、 Pb、 Zn） of environmental interest were selected scientifically and their contaminations were assessed with a variety of methods （i.e. total content standard comparison, correlation coefficient, Enrichment factor）. The results indicate that Co,Cu,Ni in Xinji coal-mining district and Co,Ni in Quanshan chemical industrial district present their richment and contamination;the contents of all six elements in soils nearby coal combustion ash are higher than that nearby coal-mining spoils in Xinji coal-mining district Regarding to the contamination of soil nearby coal-mining spoils in whole coal-mining areas, coal mining activities contribute greatly to heavy metal contamination of the soil and the metals accumulate. Moreover, the concentration of heavy metals decreases with the history of mining and weathering of the coal-mining spoils, showing their stronger mobility, especially with Co, Cu, Zn, Ni and Pd. Their contents in some soil were higher above the first-grade criteria for soil pollution established by the SEPA. However, none of them surpass the second-grade criteria, indicating that the translocation of the heavy metals resulting from the exploition and utilization of Huianan coal resources to their surrounding soil is a slow process.Meanwhile, the bioavailability and mobility of the selected heavy metals in typical soil samples were assessed by BCR three-steps sequential extraction procedure, soil certified reference materials （BCR—701） were used for analytical quality control. The result shows that Co and Cu are associated with exchangeable fractions, which represents stonger mobility;Pb in iron-manganese fraction represents stonger potential mobility;Zn and Cr existed in oxidizable and residual fraction and Ni in residues represents weak mobility or immobility. Hence, further assessment of ecological risk of heavy metals should be paid attention in the construction of eco-agriculture in Huainan coal-mine areas.更多还原