A Novel Separation Technology for Biofuel Harvesting from Wastewater

这项研究计划将开发一种膜分离技术，从废水中高效地收集生物燃料，并且在经济和环境上都是可持续的。尽管目前存在将废水中的有机物质转化为生物燃料(如生物甲烷、生物乙醇和生物柴油)的技术，但这些生物燃料是不可用的形式，如溶解的气体或液体混合物，因此需要额外的提取步骤。一种潜在的溶液膜分离过程是节能的，并且需要很小的环境足迹。然而，目前还没有有效的膜技术来分离产生的生物燃料，因为低选择性和污染使得膜过程无效和昂贵。本方案解决了当前膜技术实现从废水中高效地获取生物燃料的两个关键挑战：(1)低选择性和(2)严重污染。为了实现高选择性，将开发一种极耐湿湿的全憎膜。这种膜将放置在进料溶液(生物燃料和废水混合物)和抽出溶剂(对生物燃料具有高溶解度但对水具有低溶解度的有机溶剂)之间。这种溶解度的差异促使生物燃料以气体的形式进入抽出溶剂，而水在抽出溶剂中的溶解性较差而被拒绝，导致生物燃料的高选择性。此外，将开发一种使用刺激响应性材料的自清洁表面涂层，用于长期可持续的膜。响应外界刺激，如电压变化，膜的表面涂层破坏，清除沉积在膜表面的污物。作为一个潜在的应用，我们将展示从厌氧处理废水的流出物中长期可持续地收集生物甲烷。*开发的技术将显著增加可再生能源供应并减少温室气体(GHG)排放。在经济上，来自废水的甲烷可以补充加拿大居民区高达21%的能源使用量。在环境方面，充分利用废水中的生物甲烷相当于消除加拿大50多万辆汽车排放的温室气体。从长远来看，拟议的研究计划将为水-食品-能源关系的进一步创新铺平一条新的道路，为加拿大带来显著的经济和环境效益。

This research program will develop a membrane separation technology for efficiently harvesting biofuel from wastewater that is economically and environmentally sustainable. Although technology that converts organic materials in wastewater into biofuels (e.g., biomethane, bioethanol and biodiesel) currently exists, these biofuels are in non-usable forms such as dissolved gas or liquid mixtures, and therefore necessitates an additional extraction step. One potential solution membrane separation process is energy-efficient and requires a small environmental footprint. However, currently there exists no effective membrane technology for separation of the produced biofuels due to low selectivity and fouling that make the membrane processes ineffective and expensive.******This proposal addresses two key challenges of current membrane technology to achieve highly efficient biofuel harvesting from wastewater: (1) low selectivity and (2) severe fouling. To achieve high selectivity, an extremely wetting resistant omniphobic membrane will be developed. This membrane will be placed between a feed solution (biofuel and wastewater mixture) and a draw solvent (organic solvent that has high solubility for biofuel but low solubility for water). The solubility difference drives biofuel as a gas into the draw solvent, while water is rejected due to the poor solubility in the draw, leading to a high selectivity of biofuels. In addition, a self-cleaning surface coating will be developed using stimuli-responsive materials for membranes sustainable in the long run. In response to external stimuli such as voltage change, the surface coating of the membrane disrupts, removing the deposited foulants on the membrane surface. As a potential application, we will demonstrate the long-term sustainable harvesting of biomethane from an effluent of anaerobically treated wastewater. ******The developed technology will significantly boost renewable energy supply and reduce greenhouse gas (GHG) emissions. Economically, methane from wastewater can supplement up to approximately 21% of energy use in residential areas in Canada. Environmentally, the full utilization of biomethane from wastewater is equivalent to removing GHG emitted from more than half a million cars in Canada. In the long run, the proposed research program would pave a new path for further innovations in the water-food-energy nexus, providing significant economic and environmental benefits to Canada.