Development of novel nanocomposite membranes for hybrid forward osmosis processes

开发用于混合正向渗透过程的新型纳米复合膜

• 批准号: RGPIN-2021-03490
• 负责人: Kruczek, Boguslaw
• 金额: $ 2.4万
• 依托单位: University of Ottawa
• 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=742580
• 关键词: Development; novel; nanocomposite; membranes; hybrid

Clean water is a scarce resource because only 2.5% of all the water present on Earth is suitable for direct human consumption. Simultaneously, the growing world population, industrialization, agriculture, and pollution have dramatically increased water demand. This has led to a water crisis, one of the grand challenges of the 21st century. Membrane processes, in particular reverse osmosis (RO), are now the primary separation technology used in seawater and brackish water desalination. RO is a pressure-driven process in which the feedwater is pumped at a pressure higher than the osmotic pressure difference between the feed and permeate, allowing pure water to permeate while salts are rejected. Water desalination by RO membranes is currently the best solution to tackle the water crisis. However, it is still an expensive technology, which is not affordable by many third world countries. In forward osmosis (FO), it is the difference in osmotic pressure (feed is at ambient pressure) that drives water permeation from feed (could be wastewater) to a more concentrated draw solution. If the draw solution is seawater, the FO process will dilute it, making subsequent RO less energy-intensive and less prone to fouling and scaling problems. FO cannot be a stand-alone desalination process. However, combining RO with FO into a hybrid process could significantly reduce pure water cost by membrane desalination. Unfortunately, despite the abundance of commercial RO membranes, currently available FO membranes are not adequate for such a hybrid process. The proposed research program addresses this challenge. This proposal's heart is the approach to a novel thin-film nanocomposite (TFN) FO membrane, optimized while simultaneously optimizing the RO membrane for the hybrid process. We will also introduce a new membrane characterization method based on dynamic FO tests to evaluate the osmotic membrane's structural parameter. The new method represents the fundamental shift in this research field. TFN membranes will utilize pure and functionalized cellulose nanocrystals, i.e., safe nanoparticles, which and abundant in Canada. Desalination of brackish water is vital for the oil sand industry. Another critical application of hybrid FO-RO processes in the Canadian context is removing heavy metals from wastewaters, vital for our mining, copper smelter and textile industries. Finally, students trained through this program will gain a unique combination of skills, strong fundamentals at the intersection of science and engineering, with hands-on practical experience. They will become leaders in the field, making Canada contributions to membrane separation technology recognizable and relevant.

清洁水是一种稀缺资源，因为地球上仅有 2.5% 的水适合人类直接饮用。同时，不断增长的世界人口、工业化、农业和污染也急剧增加了水的需求。这导致了水危机，这是 21 世纪的重大挑战之一。 膜工艺，特别是反渗透（RO），现在是海水和苦咸水淡化中使用的主要分离技术。 RO 是一种压力驱动过程，其中给水在高于给水和渗透物之间渗透压差的压力下泵送，允许纯水渗透，同时拒绝盐分。 RO膜海水淡化是目前解决水危机的最佳解决方案。然而，它仍然是一项昂贵的技术，许多第三世界国家无法承受。在正向渗透 (FO) 中，渗透压（进料处于环境压力）的差异驱动水从进料（可能是废水）渗透到更浓缩的汲取溶液。如果提取溶液是海水，FO 工艺将对其进行稀释，从而减少后续 RO 的能源消耗，并且不易出现结垢和结垢问题。 FO 不能是一个独立的海水淡化过程。然而，将 RO 与 FO 结合成混合工艺可以通过膜脱盐显着降低纯水成本。不幸的是，尽管商用 RO 膜数量众多，但目前可用的 FO 膜不足以用于这种混合工艺。拟议的研究计划解决了这一挑战。该提案的核心是新型薄膜纳米复合材料 (TFN) FO 膜的方法，在优化的同时优化混合工艺的 RO 膜。我们还将介绍一种基于动态 FO 测试的新膜表征方法，以评估渗透膜的结构参数。新方法代表了该研究领域的根本转变。 TFN 膜将利用纯且功能化的纤维素纳米晶体，即安全的纳米颗粒，这种材料在加拿大很丰富。苦咸水淡化对于油砂工业至关重要。在加拿大，混合 FO-RO 工艺的另一个关键应用是去除废水中的重金属，这对于我们的采矿、铜冶炼和纺织行业至关重要。最后，通过该计划接受培训的学生将获得独特的技能组合、科学与工程交叉领域的扎实基础知识以及实践经验。他们将成为该领域的领导者，使加拿大对膜分离技术的贡献得到认可并具有相关性。