【作者】 杨春霞；

【导师】 陈永享； 彭平安；

【作者基本信息】 中国科学院研究生院（广州地球化学研究所） ， 环境科学， 2004， 博士

【摘要】 铊是稀有分散元素，在地壳中的含量很低，仅为0.75mg／kg，同时铊也是剧毒的重金属元素。我国拥有丰富的含铊矿产资源，在含铊资源开发利用的过程中，大量铊被释放入环境，污染空气、水体和土壤，并通过食物链进入生物和人体，逐步积累，引发人类群体慢性铊中毒事件或地方病。随着我国经济的快速发展，对资源的需求量越来越大，开采和利用量也越来越大，由此带来的铊环境污染隐伏危机也越来越明显。然而到目前为止国内外对含铊资源开采利用所带来的环境污染问题的研究仍很少，含铊资源利用过程中铊的迁移释放机制也不清楚，毒害元素铊也尚未纳入各级环保部门的监测范围。因此，开展含铊资源利用过程中铊迁移释放的研究不仅具有重大的理论价值，而且对我国丰富的含铊矿产资源利用中预防铊污染具有重要的指导意义。 本论文系统采集了含铊黄铁矿矿石、不同硫酸生产过程工艺环节的废渣和堆渣场周围土壤及背景土壤，利用ICP-MS测定技术和分级提取形态分析手段，对样品中的铊含量和其赋存形态进行了分析研究。研究表明(1)黄铁矿焙烧过程中，铊的赋存形态发生了明显的变化，大量的铊释放到了炉气中，并继而进入废气、废水和废渣中，对环境的危害性很强，因此铊污染控制的关键是从工艺环节上控制铊进入气体的量，从而减弱铊进入废气、废水和废渣的量。(2)冶炼废渣在自然淋滤过程中铊有明显的迁移释放能力，废渣中铊的赋存形态和环境介质条件(pH、温度及废渣矿物组分)是控制其迁移释放能力的主要因素。(3)废渣在长期的自然淋滤过程中已对堆渣场周围土壤构成了明显的铊污染，不同来源的铊在土壤中的迁移与富集行为明显不同，污染来源的铊在土壤中的迁移活动性明显强于自然来源的铊，具有更强的生物有效性，对环境的危害也更强。土壤中不同矿物组分对铊污染物的吸附能力明显不同，土壤pH是影响其结合能力的关键因素，土壤的酸化将明显增强土壤中铊污染物的迁移活动性。 硫酸废渣年排放量大，且露天堆放，在酸雨淋滤作用下，废渣铊污染物可持续快速的释放入周边环境。此外，在其再次堆积、搬运和利用过程中可造成T1污染范围迅速扩大。由于硫酸厂多位于居民区农田附近，T1污染所引起的生态环境的恶化，直接关系到公众健康利益。因此，含T1黄铁矿利用过程中区域性T1污染的防治已成了一个不容忽视的环境问题。更多还原

【Abstract】 Thallium (Tl) is a severe toxicity and scattered heavy metals, and has very low concentration in the earth’s crust (0.75mg/kg). Abundance of mineral resource containing Tl has been found in our country. Tl could be released into atmosphere, water and soil, and then enter into and accumulated in person and animals body through food chain, induce Tl chronic poisoning or endemic disease to human beings. With the rapid development of economy in our country, the demand for mineral resource will be gradually increase, the degree of exploitation will be increased simultaneity, and the environment crisis of Tl will be caused more and more serious. However, there has no much attention on the Tl pollution problems caused by the exploitation of mineral resource containing Tl in the international world and the mechanism of migration and release of Tl is still unclear now, and toxicity Tl has not been monitored as one pollutants by environmental protection bureau. So the systemic studies the mechanism of migration and release of Tl not only has important theoretic values, but also has magnitude instruct significance for prevent Tl pollution in the exploitation of mineral resource containing Tl.In this work, samples were collected from different pyrite ores, sulfur acid slag collected from different phase of sulfur acid production, soils profiles around the slag pile site and background soil. Tl concentrations and forms in samples were analyzed by ICP-MS and sequential extraction procedure. It indicate that (1) Tl forms changed after pyrite roasting and a lot of Tl released into gas phase, then let into waste gas, wastewater and slag, and will do harm to environment. So the key of controller Tl pollution was control Tl release to gas phase in sulfur acid production, to prevent Tl let into waste gas, wastewater and slag; (2) Thallium in slag has distinct release ability under natural leaching and was affected by its forms and some conditions (such as pH, temperature and components of slag); (3) The soil around the slag pile has been serious polluted by Tl in slag in the process of natural leaching. Thallium from different source has different geochemical behaviors in soils. Anthropogenic Tl has stronger mobility than natural Tl, so has high bioaviability and hazardless for environment. The various soil components have different ability to adsorbed Tl and mainly effected by soil pH. Thallium mobility will be enhanced with soil acidification.The sulfur acid slag has high annul production and piled in air, the Tl pollutant will be rapidly released into environment in the process of leaching. Moreover, thetranslation, piling again and using of slag will extend the range of contamination. The sulfur acid plant usually lies in the residential area, so ecology environment deteriorate by Tl pollutant will directly related with behalf of public health. So the area of Tl prevention and cure become one of a urgent environment problem.更多还原