Novel Effluent Desalination Processes: Sustainable Water Recovery and Energy Generation in Mining Sites

新型污水淡化工艺：矿场可持续水回收和能源生产

• 批准号: RGPIN-2020-04262
• 负责人: Kolliopoulos, Georgios
• 金额: $ 2.4万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=739806
• 关键词: Novel; Effluent; Desalination; Processes; Sustainable

The proposed research program aims to reduce the environmental footprint of the mining and metals industry, especially to the extent related to water usage. We aim to develop innovative holistic scalable energy efficient and environmentally friendly effluent desalination processes. The objectives are: (i) to reduce the contaminated aqueous waste volume by recovering water from process solutions, effluents, and tailings ponds at low cost, (ii) to upgrade the valuable metal content (if any) in the remaining brine, thus making its re-processing economically viable, and (iii) to utilize the controlled mixing of effluents in the tailings ponds to generate renewable energy. The proposed research program will train HQP in innovative processes to recover water and energy from effluents and tailings ponds. We hypothesize that these novel processes will simultaneously increase the water recovery yield from effluents and lower the energy footprint of the sector. We intend to primarily focus on technologies that operate at sub-zero temperatures to take advantage of the Canadian cold winter climate and recover water in the form of pure ice. Not only is the energy for freezing 7 times less than that of evaporation, but also it is free several months per year in Canada during winter. The processes we propose to work on are freeze concentration (FC) and gas hydrate desalination (HyDesal). The novelty of our work is based on the use of cold ultra fine gas bubbles (i.e., mixture of micro- and nano-bubbles). Under controlled conditions, the bubbles will serve as nuclei for ice formation, resulting in the recovery of water in the form of pure tiny ice crystals, without allowing impurities to enter into the ice matrix. Also, we intend to simplify the treatment of effluent streams and tailings for water recovery upon passing the water from these multi-component aqueous streams into environmentally benign single-component draw solutions via forward osmosis (FO). FO requires no external energy input; instead, it is driven by the osmotic pressure difference between the effluents and more concentrated draw solutions. FC will be used to recover clean water from the resulting diluted draw solution, which requires energy. Finally, we intend to develop a membrane process, salinity gradient power, to recover the released energy of mixing of the effluents discharged into the tailings ponds through their controlled mixing in the latter, similar to how waste heat is recovered from plants. This research program contributes to the protection of people's right to clean water and advances the competitiveness of the Canadian mining and metals industry in an era that environmental legislation barriers become stricter due to climate change. It also generates a strong potential for collaboration with Canadian and international organizations and industries and aims to position Canada as the world's prominent country in zero liquid discharge research, regulations, and applications.

拟议的研究计划旨在减少采矿和金属行业的环境足迹，尤其是在与用水相关的范围内。我们旨在开发创新的整体可扩展节能和环保的废水脱盐过程。目的是：（i）通过从过程解决方案，废水和尾矿池塘中恢复水，以低成本的价格恢复水，（ii）升级剩余的盐水中的有价值的金属含量（如果有的话），从而使其经济上可行的可行性上可行，以及（iii），以及（iii），以供应的能量构成式填充的质量，以使其构成越来越多。拟议的研究计划将培训HQP的创新过程，以从废水和尾矿池塘中回收水和能量。我们假设这些新型过程将同时增加从废水中的水回收率，并降低该行业的能量足迹。我们打算主要关注在零温度下运行的技术，以利用加拿大寒冷的冬季气候，并以纯冰的形式恢复水。不仅冻结的能量比蒸发少7倍，而且在冬季，加拿大每年免费的几个月。我们建议处理的过程是冻结浓度（FC）和气体水合脱盐（Hydesal）。我们工作的新颖性是基于使用冷的超细气泡（即微泡和纳米泡的混合物）的使用。在受控条件下，气泡将作为冰形成的核，导致以纯微小的冰晶形式恢复水，而不允许杂质进入冰基质。此外，我们打算简化从这些多组分水流将水从这些多组分水流中传递到环境良性的单一组分溶液（FO）时，以简化流出流和尾矿的处理，以进行水回收。 FO不需要外部能量输入；取而代之的是，它是由废水和更浓缩溶液之间的渗透压差驱动的。 FC将用于从所得稀释的Draw溶液中回收清水，这需要能量。最后，我们打算开发一种膜过程，即盐度梯度能力，以通过后者的控制混合物来恢复排放到尾矿池的混合能量，类似于从植物中回收废物的方式。该研究计划有助于保护人们清洁水的权利，并在环境立法障碍由于气候变化而变得更加严格的时代，增进加拿大采矿和金属行业的竞争力。它还具有与加拿大和国际组织和行业合作的强大潜力，并旨在将加拿大作为世界上杰出国家的零液体排放研究，法规和应用。