Membrane distillation for sustainable desalination and water treatment

包括英国在内的全世界目前都面临着从河流、池塘或湖泊以外的水源生产淡水的需求。这对淡水资源有限的国家至关重要，对可能遭受意外干旱的区域也至关重要。全球人类和工业活动对淡水的需求分别为10%和20%（农业占其余70%）。然而，在工业化国家，工业消耗了一半以上的家庭用水。全世界对可排放回河流或其他水体的水的质量进行管理的政策越来越严格，因此，对于推动使用能够产生具有所需质量但足迹更小且比目前使用的传统技术更经济的水的技术至关重要。因此，该项目的目的是通过开发具有长期稳定性（即抗润湿性能）的高渗透性石墨烯膜来推进水净化（膜蒸馏，MD）的可持续技术的使用。MD被认为是可持续的，因为进行分离所需的低品位热能可以通过太阳能集热器或发电厂和其他工业操作的废热获得。此外，它允许在单级工艺中处理高盐度盐水，100%排除杂质，不需要昂贵的加压膜系统，因为它在大气压下操作。此外，所开发的MD膜可以在包括纺织工业在内的一系列工业过程中提高脱盐盐水和废水流出物的分离效率和回收有价值的产品。

The world, including the UK, is currently facing the need for producing fresh water from sources other than rivers, ponds or lakes. It is of paramount importance for countries where freshwater resources are limited, but also for regions that can suffer from unexpected draughts. Demand for fresh water for human use and industrial activities worldwide are 10 and 20%, respectively (agriculture accounts for the remaining 70%). However, in industrialised nations, industries consume more than half of the water available for domestic use. Policies regulating the quality of water that can be discharged back into rivers or other water-bodies is becoming stricter worldwide, and therefore is crucial to advance on the use of technologies that can generate the water with the required quality but lower foot print and more economically than the conventional technologies currently used. Thus, the aim of this project is to advance on the use of a sustainable technology for water purification (membrane distillation, MD) by developing highly permeable graphene-based membranes with long term stability (i.e. anti-wetting properties). MD is considered to be sustainable as the low-grade thermal energy required to do the separation can be obtained by means of thermal solar collectors or waste heat from power plants and other industrial operations. In addition, it allows to treat highly saline brines with 100% rejection of impurities in a single stage process, with no need for costly pressurised membrane systems, as it is operated under atmospheric pressure. Furthermore, the developed MD membranes can propel the separation efficiency and recovery of valuable products from desalination brines and wastewater effluents in a range of industrial processes including the textile industry.