Geotechnical evaluation of tailings thickening

经济的繁荣受新能源和新材料的勘探以及现有储量的开发的影响。加拿大采矿业为经济贡献了400亿美元，约占国内生产总值的4%。这一重要活动与大量不断增加的各种性质和程度的矿山废物有关。矿山尾矿（矿石加工过程中产生的矿浆）的处理尤其具有挑战性，因为它们的沉降速度慢，而且在废物控制设施中存在高浓度的有毒水。世界各地多次发生尾矿坝溃坝事故，造成大量尾矿污染，引起公众对传统尾矿处理方式的强烈不满。该行业一直积极开发新的废物管理方法，以尽量减少其对环境的影响。拟议的研究将通过研究浆液增稠的创新方法，为贱金属采矿作业设计可持续（成本效益、环境友好和社会可行）的工程解决方案。具体目标包括：(a)设计不分离的浓缩料，使絮凝效果最大化；(b)改善浓缩过程中的尾矿脱水，提高重力浓缩机的效率；(c)预测增稠剂底流的长期行为，评价尾矿库水下处理。这项研究将有助于产生不分离的尾矿流，其中大部分工艺水被去除并回收用于矿石选矿。低含水量工程材料将占用更小的处置面积，可以在相对较短的时间内回收作为有用的景观。除了增加尾矿库的储存能力外，新的尾矿库管理解决方案将有助于减少由于酸性岩石排水和金属浸出而造成的环境责任。

Economic prosperity is influenced by the exploration of new sources of energy and materials along with the development of existing reserves. The Canadian mining industry contributes $40 billion to the economy and accounts for about 4% of the Gross Domestic Product. This important activity is associated with large volumes of ever increasing mine wastes of variable nature and extent. The mine tailings (slurries generated during ore processing) are particularly challenging because of their slow settling rates and high standing toxic waters in the waste containment facilities. Several tailings dam failures around the world resulted in massive contamination causing acute public distress over the conventional practice of tailings disposal. The industry has been proactive in developing novel waste management methods to minimize its environmental footprint. The proposed research will devise sustainable (cost effective, environmentally friendly, and socially viable) engineering solutions for base-metal mining operations by investigating the innovative method of slurry thickening. The specific goals include the following: (a) design of nonsegregating thickener feed to maximize the effectiveness of flocculation; (b) improve tailings dewatering during thickening to increase the efficiency of gravity thickeners; and (c) predict the long-term behavior of thickener underflow to evaluate subaqueous disposal in tailings ponds. This research will help produce nonsegregating tailings streams with bulk of the process water removed and recycled back for ore beneficiation. The low water content engineered materials will occupy a much smaller disposal area that can be reclaimed as a useful landscape in a relatively short time. In addition to an increased storage capacity of the tailings impoundments, the new tailings management solutions will help decrease environmental liabilities due to reduced acid rock drainage and metal leaching.