Arsenic and antimony immobilization from mineral processing solutions and waste waters

矿物资源的开采和采矿活动的增加对环境造成了更大的压力，因此必须制订适当的水/废物管理程序。砷和锑是采矿活动中通常释放到环境中的有毒元素。西北地区Giant Mine金矿从1948年到2004年的采矿作业已经产生了23.7万吨三氧化二砷粉尘。三氧化二砷可溶于水，污染了周围地区的土壤和建筑物。在另一个案例中，在安大略省巴尔默敦坎贝尔矿的尾矿孔隙水（地下水）中检测到砷浓度高达100毫克/升。这一砷含量比加拿大饮用水质量标准（0.010毫克/升）的最高可接受砷含量高出1万倍。******由于高品位和清洁的矿床越来越难以找到，因此需要发展以更安全、环境更可持续的方式提取含砷和锑的复杂矿体、矿物和金属的工艺。这对于加拿大采矿业的持续财政可持续性至关重要，采矿业是加拿大经济中最大的雇主。如果不进一步发展强有力的有毒元素管理解决方案，复杂矿体的处理是不可能的。有必要开发一种方法，使有毒元素固定（沉淀）为安全、无毒和稳定的化合物。特别是，沉淀物必须具有数千年的长期环境稳定性。******申请人建议建立一个研究计划，研究砷和锑的固定过程。这项研究计划的长期目标是全面了解采矿过程中这两种元素的化学性质，以及环境中含砷和含锑沉淀物的长期稳定性。在未来五年内，即短期目标，建议建立关于砷和锑氧化机制的坚实知识，研究通过可持续生物氧化和生物沉淀过程固定砷的可行性，制定可靠的方案来评估砷和锑沉淀物的长期稳定性，并生成最稳定的砷和锑化合物/沉淀物的全球清单。作为采矿业选择/发展工艺的参考文件。预计通过该研究项目开发的知识和HQP将受到加拿大采矿业的高度追捧。本研究项目前5年将培养2名博士生和2名硕士生。

The increased extraction of mineral resources and mining activities have added pressure on the environment, therefore it is imperative that proper processes for water/waste management are developed. Arsenic and antimony are among the toxic elements which are usually released into the environment from mining activities. The mining operations at the Giant Mine gold mine in the Northwest Territories, which was operated from 1948 to 2004, have created 237,000 tonnes of arsenic trioxide dust. Arsenic trioxide is soluble in water and has contaminated soil and buildings in the surrounding area. In another case, arsenic concentrations of up 100 mg/L were detected in the tailing porewater (underground water) of Campbell Mine, Balmertown, ON. This arsenic level is 10,000 times higher than the maximum acceptable arsenic level by Canadian drinking water quality standard, which is 0.010 mg/L.******As high grade and clean deposits are becoming more difficult to find, there is a need for the development of processes to extract complex arsenic and antimony-containing orebodies, minerals and metals in a safer, more environmentally sustainable manner. This is essential for the continued financial sustainability of the Canadian mining industry, the largest employer of the Canadian economy. Processing of complex orebodies is not possible without further development of robust solutions for the management of toxic elements. There is a need for development of processes that can immobilize (precipitate) the toxic elements as safe, non-toxic and stable compounds. In particular, the precipitates must have long term environmental stability for thousands of years. ******The applicant proposes to establish a research program to study the arsenic and antimony immobilization processes. The long-term goals of this research program are to develop a comprehensive understanding of the chemistry of the two elements in the mining processes, and the long-term stability of the arsenic and antimony-containing precipitates in the environment. During the next five years, i.e. short-term objectives, it is proposed to generate a solid knowledge of the arsenic and antimony oxidation mechanisms, investigate the feasibility of arsenic immobilization through sustainable bio-oxidation and bio-precipitation processes, develop a reliable protocol for long-term stability assessment of arsenic and antimony precipitates, and generate a global list of most stable arsenic and antimony compounds/precipitates, to be used as a reference document for process selection/development by the mining industry. It is expected that the knowledge, and HQP developed through this research program will be highly sought after by the Canadian mining industry. Two Ph.D. students and two Master's students will be trained through the first 5-year round of this research program.