Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, PR China; Department of Sanitary Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600 GA, Delft, the Netherlands.
Engineering Research Center of Environmental Materials and Membrane Technology of Hubei Province, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, PR China.
Water Res. 2020 Feb 1;169:115180. doi: 10.1016/j.watres.2019.115180. Epub 2019 Oct 12.
Highly efficient and economic treatment of wastewater sludges and wastewaters in one way is a challenging issue in the water treatment field. Herein we present a waste-to-resource strategy for rational fabrication of low-cost ceramic membranes, which simultaneously addresses the treatment of heavy metal-laden sludges and the separation of oil-in-water (O/W) emulsions. A thermal conversion mechanism is proposed for complicated reactions between simulated nickel-laden wastewater sludge and bauxite mineral. In addition to full stabilization and recycling of heavy metal wastewater sludges, rational tailoring of ceramic membrane structures can also be realized to achieve high water flux and favorable mechanical and surface properties. With rational structure design, the tailored spinel-based ceramic membranes exhibited high rejection and high flux (7473 LMH·bar) simultaneously for separation of oily wastewater, outperforming other reported state-of-the-art ceramic membranes. The membrane fouling mechanism revealed the dominance of cake layer formation at low cross flow velocities, while a combined model of cake layer formation and pore blocking dominated membrane fouling at high cross-flow velocities. The proposed strategy can be potentially extended toward design of functional ceramic membranes derived from other heavy metal wastewater sludges and for other water treatment applications.
高效且经济地处理废水污泥和污水是水处理领域的一个挑战。在此，我们提出了一种从废物中获取资源的策略，用于合理制备低成本陶瓷膜，同时解决了重金属污泥的处理和油水（O/W）乳液的分离问题。提出了模拟含镍废水污泥与铝土矿之间复杂反应的热转化机理。除了充分稳定和回收重金属废水污泥外，还可以实现陶瓷膜结构的合理剪裁，以实现高水通量和良好的机械和表面性能。通过合理的结构设计，定制的尖晶石基陶瓷膜在分离含油废水时表现出高截留率和高通量（7473 LMH·bar），优于其他报道的最先进的陶瓷膜。膜污染机制揭示了在低错流速度下，滤饼层形成占主导地位，而在高错流速度下，滤饼层形成和孔堵塞的组合模型占主导地位。该策略可潜在地扩展到其他重金属废水污泥和其他水处理应用中设计功能陶瓷膜。
