Mineralogical Characterization for Reducing the Environmental Impact of Mining Rare Metals

减少稀有金属开采对环境影响的矿物学表征

• 批准号: RGPIN-2016-03736
• 负责人: Jamieson, Heather
• 金额: $ 3.5万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=707937
• 关键词: Mineralogical; Characterization; Reducing; Environmental; Impact

The objective of my research program is to characterize the minerals or compounds that contain potentially hazardous metals in mine tailings, waste rock and contaminated dust, soils and sediments. By direct and quantitative identification of the host metal species, particle size and texture, I can predict whether metals will be released to the aquatic environment or retained in the solid waste in the form of secondary minerals. The results of this research will improve risk assessment and remediation design for proposed, operating and orphaned mines in Canada, especially in the Canadian North where much of the fieldwork will occur. The results will be useful to decision-makers such as government regulators, environmental consultants, mining companies, and nearby communities including First Nations. The broader scientific application is the clarification of the risk to human and ecological health associated with mine waste, and prediction of the long-term stability of these materials in the environment. The emphasis will be on particles that contain rare and understudied metals such as rare earth elements (REEs), indium, lithium, niobium and cobalt, some of which are termed critical or strategic metals as they are important for electronics, green technology and military applications. Very little is known about the controls on environmental mobility of these elements, such as the transformation of primary ore minerals to secondary weathering products, the importance of colloidal transport, or the long-term stability of the host minerals in tailings impoundments, wetlands and soils. I will build on my established expertise in characterizing mine waste materials contaminated with arsenic and antimony. Finding and identifying metal-bearing particles in tailings, soils, sediments and dust is challenging as they are usually small, rare, and poorly crystalline. Even for samples that exceed regulatory guidelines, the bulk concentration may be much less than 0.1%. Moreover, in most samples, there are multiple mineralogical hosts of metals, and distinguishing these and evaluating the relative proportions of the metal-hosting phases is important. Bioavailability and long-term stability depend on host mineral composition, its particle size, and textural relationships, such as encapsulation by other minerals. I have supervised 32 graduate students and postdoctoral fellows in the last six years, all of whom are working in the field of environmental geochemistry. The proposed program will train 11 HQP with exposure to advanced analytical techniques, world-class collaborators, extensive fieldwork, and interaction with the communities, policy makers and industry that would use their research. This program will benefit from my experience in the Canadian North and ongoing collaboration with mining companies, First Nations, and government agencies.

我的研究项目的目标是表征尾矿、废石以及受污染的灰尘、土壤和沉积物中含有潜在危险金属的矿物或化合物。通过直接定量识别主体金属种类、颗粒大小和质地，我可以预测金属是否会释放到水生环境中或以二次矿物的形式保留在固体废物中。这项研究的结果将改善加拿大拟建、运营和废弃矿山的风险评估和修复设计，特别是在加拿大北部，那里将进行大量实地工作。研究结果将对政府监管机构、环境顾问、矿业公司以及包括原住民在内的附近社区等决策者有用。更广泛的科学应用是澄清与矿山废物相关的人类和生态健康风险，并预测这些材料在环境中的长期稳定性。 重点将放在含有稀有和尚未研究的金属的颗粒上，例如稀土元素 (REE)、铟、锂、铌和钴，其中一些被称为关键或战略金属，因为它们对电子、绿色技术和军事应用很重要。人们对这些元素的环境迁移性控制知之甚少，例如原生矿石矿物向次生风化产物的转化、胶体迁移的重要性或尾矿库、湿地和土壤中主体矿物的长期稳定性。 我将利用我在表征受砷和锑污染的矿山废料方面的既定专业知识。在尾矿、土壤、沉积物和灰尘中寻找和识别含金属颗粒具有挑战性，因为它们通常很小、稀有且结晶度较差。 即使对于超出监管指南的样品，总体浓度也可能远低于 0.1%。此外，在大多数样品中，存在多种金属矿物学主体，区分这些金属并评估金属主体相的相对比例非常重要。生物利用度和长期稳定性取决于宿主矿物成分、其粒径和结构关系，例如其他矿物质的封装。 在过去的六年里，我指导了 32 名研究生和博士后，他们都在环境地球化学领域工作。拟议的计划将培训 11 名 HQP，让他们接触先进的分析技术、世界一流的合作者、广泛的实地工作以及与将使用其研究成果的社区、政策制定者和行业的互动。该计划将受益于我在加拿大北部的经验以及与矿业公司、原住民和政府机构的持续合作。