Decontamination of Soil Containing Residual Mercury from Mining Operations

9800643 Fernando这一奖项旨在支持一项研究，该研究旨在最大限度地减少土壤净化过程对环境的影响，土壤污染是在从美国和墨西哥开采的矿石中提取金银时使用汞造成的。这项工作包括与墨西哥瓜达拉哈拉自治大学的Tetsuya Ogura博士合作，研究从墨西哥萨卡特卡斯受污染地区获得的土壤。目前在那里使用的方法是用硫代硫酸钙水溶液处理被这些金属污染的土壤，这种溶液是由二氧化硫通过石灰和单质硫的水悬浮液产生的。由此产生的金属污染物溶液与金属接触，沉淀出含有汞合金的元素汞，这些元素汞可以通过加热使汞合金汽化而从汞合金中提取出来。过程控制对于避免其对空气、水和土壤的潜在污染影响非常重要。预计该项目的结果将提供有关如何设计和实施所研究的过程以获得其利益并尽量减少其潜在的负面环境影响的知识。研究还将确定该工艺相对于目前可用的从土壤中去除汞的替代技术的优点和缺点。该项目通过与墨西哥国家科学技术研究所（CONACyT）的合作方案得到部分支持

9800643 Fernando This is an award to provide support for research on minimizing the environmental impact of a process for decontamination of soil that had been contaminated by use of mercury in extracting gold and silver from ores mined in the United States and Mexico. The work involves collaboration with Dr. Tetsuya Ogura of the Autonomous University of Guadalajara in Mexico on soils obtained from contaminated sites in Zacatecas, Mexico. The process currently in use there involves treatment of soil contaminated by these metals with an aqueous solution of calcium thiosulfate produced by passing sulfur dioxide through an aqueous suspension of lime and elemental sulfur. The resultant solution of metal contaminants is contacted with metals that precipitate elemental mercury containing amalgamated gold and silver which can be extracted from the amalgam by heating it to vaporize the mercury. Process control is important to avoid its potential pollutional impact on air, water and soil. Results of this project are expected to provide knowledge as to how the process being studied can be designed and conducted to obtain its benefits and minimize its potential negative environmental impact. Research will also identify the advantages and disadvantages of the process over currently available alternative technologies for removing mercury from soil. This project is being partially supported through a program of collaboration with the Nacional de Ciencia y Tecnologia (CONACyT) of Mexico.***