Sustainable and Lean Technologies for Critical Elements Recovery from Oil sands tailing streams

虽然稀土元素被认为是“稀有元素”，但它们在地壳中相对丰富;然而，与其他低丰度金属不同，它们很少形成经济矿床。稀土的应用范围很广，从可充电电池到石油炼制。随着全球需求的不断增长，回收利用目前无法取代从矿石中提取稀土元素的初级开采，寻找替代来源以确保长期供应链具有挑战性。在现有的替代品中，油砂尾矿被视为潜在的未开发的稀土储量。另一方面，生物湿法冶金是利用微生物的提取冶金的一个分支，代表了从油砂矿床/尾矿流中提取这些元素的可持续技术。目前，传统的稀土处理方法复杂，成本高，需要苛刻的条件，并产生大量含有钍，铀，氟化氢和酸性废水的有毒废物。相比之下，生物湿法冶金提供了一种更具成本效益和环境可持续性的替代方案，分别占世界黄金和铜需求的5%和20%。与传统的化学方法相比，研究用于回收稀土的新生物处理方法可能提供可持续的替代方案。因此，本项目将解决如何应用环境友好的过程（即，油砂尾矿流（粗尾矿、流体细尾矿和泡沫处理尾矿）的生物湿法冶金）可以浸出和提取对当今“更智能”和“更环保”技术至关重要的关键元素（即稀土元素）。此外，尽管对油砂尾矿有深入的了解，但对石油废物流中的稀土元素的地球化学影响，环境命运或动员以及它们如何影响水化学，气体排放，脱水和沉积过程知之甚少。这些尚未解决的问题将在本研究中得到解决。除了推进新的生物湿法冶金方法外，拟议的研究计划还将开发创新的湿法冶金工艺，作为直接从油砂中提取有价值金属而无需尾矿再处理的第二种选择。不同的开采方法将通过先进的回收方案得到补充。通过建模、仿真系统和技术经济分析，最终建立一个完整的工艺流程。这项研究的结果将为尾矿管理提供更好的实践，同时降低环境影响和责任的风险。包括本科生和研究生在内的高素质人员将接受微生物生物技术、采矿和土木工程、化学工程和地球化学方面的培训，使他们能够在可持续采矿领域担任未来的领导职务。

Although Rare Earth Elements (REEs) are considered "rare elements", they are relatively abundant in the Earth's crust; however, unlike other low abundance metals, they are rarely form economic deposits. The application for REEs are broad ranging from their use in rechargeable batteries to petroleum refining. With the growing global demand, recycling cannot currently replace primary mining of REEs from ores and identifying alternative sources to secure the supply chain on the long term is challenging. Among the available alternatives, oil sands tailings are seen as a potential untapped reservoir for REEs. On the otherside, biohydrometallurgy, a branch of extractive metallurgy that uses microbes, represents a sustainable technique for extracting these elements from oil sands deposits/tailing streams. Currently, conventional REEs processing methods are complex, costly, require harsh conditions and generate large amounts of toxic waste containing thorium, uranium, hydrogen fluoride, and acidic wastewater. In contrast, biohydrometallurgy presents a more cost-effective and environmentally sustainable alternative and covers around 5% and 20% of the world's gold and copper demands, respectively. New bioprocessing methods investigated for the recovery of REEs may offer a sustainable alternative compared to conventional chemical approaches. Thus, this project will address how the application of environmentally benign processes (i.e., biohydrometallurgy) on oil sands tailing streams (coarse tailings, fluid fine tailings, and froth treatment tailings) can leach and extract critical elements (i.e. REEs) that are essential for today's "smarter" and "greener" technologies. Besides, despite the deep knowledge on oil sands tailings, little is known about the biogeochemical implications, environmental fate or mobilization of REEs in oil waste streams particularly and how they affect water chemistry, gas emissions, dewatering and deposition processes. These unresolved questions will be addressed in this research. In addition to advancing new biohydrometallurgy methods, the proposed research program will also develop inovative hydrometallurgy process as a second option for extracting valuable metals directly from oils sands without the need for tailings reprocessing. Different extraction approaches will be latter complemented through advanced recovery options. A whole flow-sheet will be finally established through modelling, simulation systems and techno-economic analysis. The results of this research will offer better practices for tailings management while reducing the risks of environmental impacts and liabilities. Highly qualified personnels (HQPs) uncluding undergraduate and graduate students will be trained in microbial biotechnology, mining and civil engineering, chemical engineering and biogeochemistry, positioning them for future leadership positions in sustainable mining.