GOALI: In situ generation of two phase flows to eliminate membrane concentration polarization and fouling

目标：原位生成两相流以消除膜浓差极化和污染

• 批准号: 2050326
• 负责人: Manish Kumar
• 金额: $ 4.06万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-10-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2050326&HistoricalAwards=false
• 关键词: GOALI; situ; generation; two; phase

PI Name: Darrell VelegolProposal Number: 1705278Membrane technologies, especially reverse osmosis (RO), are now at the forefront of water purification from lower-quality water sources such as seawater, brackish water, and wastewater. The objective of this project is to minimize membrane fouling by producing oxygen at the membrane surface to impede the growth of biofilms on the membrane. Biofouling has the largest negative impact on desalination membrane performance. This fundamental research has the potential to transform membrane performance by significantly decreasing the energy use of membranes and increasing their usable lifetime. The fundamental principles learned are anticipated to lead to solutions that are scalable and commercially viable and can improve municipal and industrial water treatment to help meet the growing national demand for potable water.Numerous efforts have focused on improving RO efficiency by pretreatment, minimizing concentration polarization (CP), and mitigating fouling. Current methods have not overcome the problem in a feasible manner, especially for concentration polarization; however, no study has been reported on the application of microbubbles generated in situ to disturb the CP boundary layer. The hypothesis is that catalytically generating microbubbles at a membrane surface will produce localized micromixing, which will significantly reduce both concentration polarization and particle-bacteria-organic fouling. To test the overall hypothesis and meet the objective, three important fundamental questions must be answered, and form the intellectual merit of this research: 1) What is the rate of microbubble formation, and the microbubble size distribution, given a particular catalyst type, catalyst loading fraction, hydrogen peroxide (H2O2) dosing profile, and local pressure (i.e., must exceed Henry's law solubility)? 2) For a given microbubble production rate and size distribution, what is the increase in water effluent due to the different mechanisms of micromixing for concentration polarization, and liftoff for membrane fouling species? and 3) For a given microbubble production rate, what is the disinfection capacity for biofilm-forming microorganisms using the produced oxidant (reactive oxygen species), at production levels that avoid membrane damage? The approach is to incorporate catalysts in the membrane module (either membrane surface or spacers), and then during the operation of the membrane, to inject pulses of H2O2 or other reactants that will produce microbubbles at the membrane surface. A primary figure of merit for this work is an increased water flux through the membrane over time. The broader impacts of this proposal focus on educating Ph.D. students (including internships with Dow Chemical, our NSF GOALI partner) and undergrads, as well as technological commercialization (with partner Dow Chemical). Producing microbubbles and generating localized micromixing could be achieved at commercial scale. Ph.D. and undergrad education as well as internships and entrepreneurship training will form part of the student experience.

PI名称：Darrell Velegolpropoposal编号：1705278个大脑技术，尤其是反渗透（RO），现在来自海水，咸水，咸水和废水等低品质水源的水净化的最前沿。 该项目的目的是通过在膜表面产生氧气来最大程度地减少膜结垢，从而阻碍生物膜在膜上的生长。 生物污染对海水淡化膜性能的负面影响最大。 这项基本研究有可能通过显着降低膜的能量使用并增加其可用寿命来改变膜性能。 预计所学的基本原则将导致可扩展和商业上可行的解决方案，并可以改善市政和工业水处理，以帮助满足国家对饮用水的需求不断增长。努力的努力集中在通过预处理，最小化集中度（CP）（CP）以及降低燃料来提高RO效率。 当前的方法尚未以可行的方式克服问题，尤其是对于浓度极化；但是，尚无关于原位生成的微泡的应用来干扰CP边界层的研究。 假设是在膜表面催化产生的微泡将产生局部微混合，这将显着降低浓度极化和颗粒 - 细菌 - 细菌 - 有机结垢。 为了检验总体假设并达到目标，必须回答三个重要的基本问题，并构成这项研究的智力优点：1）鉴于特定的催化剂类型，催化剂载荷分数，氢过氧化氢，过氧化氢（H2O2）的剂量概况以及本地压力（i.e.e.e.e solige soliys），微生物形成的速率和微生物大小分布是多少？ 2）对于给定的微泡产量和尺寸分布，由于浓度极化的微质子机制以及膜结垢物种的升降，水废水的增加是多少？ 3）对于给定的微泡产量，使用产生的氧化剂（活性氧）（避免膜损伤的生产水平），生物膜形成微生物的消毒能力是多少？ 该方法是将催化剂掺入膜模块（膜表面或垫片），然后在膜操作过程中，以注入H2O2的脉冲或其他将在膜表面产生微泡的反应物。 这项工作的主要优点是随着时间的流逝，通过膜的水通量增加。 该提案的更广泛影响着重于教育博士学位。学生（包括Dow Chemical，我们的NSF Goali合作伙伴实习）和本科生，以及技术商业化（与合作伙伴DOW Chemical）。 可以在商业范围内实现生产微泡和生成局部微混合。 博士本科教育以及实习和创业培训将成为学生体验的一部分。